20120077 Ver 1_Stormwater Info_20120531

Del Webb
0,�;7 - 2,9 - ZVI ?
Prepared for: Randy King ® Pulte Homes
1225 Crescent Green Drive - Suite = 250
Cary, NC 27518
[phone]

Table of Contents
Narrative
Preliminary BMP Sizing Calculations
Required Maps and Information

Narrative

Del Webb
STORM WATER IMPACT ANALYSIS
General Description
Del Webb will be an approximately 296 -acre community south of Leesville Road
east of the intersection with Doc Nichols Road. The tracts that will make up the
development are currently in the county but will be annexed. The properties
are zoned Rural Residential and the land use is a mixture of agricultural,
residential, and vacant. The entire project is in the Neuse river basin and the
majority of the site is not in a watershed protection district. Approximately 8
acres in the northern portion of the site drains to the F /J -B Watershed Protection
District. All impervious surface added in this portion of the site will be directed
away from the F /J -B in post - development. There are multiple streams located
onsite and FEMA 100 -year floodplain is associated with a few reaches.
The development for the site will consist of single - family homes, a clubhouse
area, and associated streets and parking. The community will be a dense
residential development.
Water Quality
The development is greater than 42% impervious; therefore, 40% of the required
nitrogen and phosphorous removal is required onsite. The required onsite
nitrogen and phosphorous removal will be provided by multiple BMP's located
throughout the site. All of the required phosphorus removal will be provided by
the onsite BMP's, but further nitrogen reduction will be provided through a
purchase of offset credits. The total post - development nitrogen and
phosphorous export for the site will not exceed 2.2 Ib /ac /yr and 0.50 Ib /ac /yr
respectively.
BMP's
Two types of BMP's will be located throughout the site to attenuate the peak
flow rate of their contributing watershed's and or provide nutrient removal.
Twelve water quality ponds will have surface areas large enough to accomplish
85% TSS removal, as calculated using the surface area multipliers, based on
average depth and the impervious percentage of their drainage basins. The
water quality ponds will utilize low flow orifices that will slowly draw down the
temporary pool over a period of 2 -5 days. Level spreaders are designed at the
outfall of each BMP and are sized for the 10 -year rainfall runoff. Each level
spreader will discharge to an engineered filter strip at a slope of less than 5%
that will be planted with grass and maintained in perpetuity. Rainfall runoff in
excess of the 10 -year event will bypass the level spreaders by means of the

water quality ponds' emergency spillways for all ponds except for WQ #9.
Runoff in excess of the 10 -year rainfall event outflow from WQ #9 will bypass it's
level spreader by means of a flow splitter box where it will be directed to a
separate outfall with a plunge pool upstream of the buffer.
Two level spreaders have been designed to provide diffuse flow of the runoff
from their contributing drainage basins into a stream buffer. The level spreaders
were designed so that their lengths are greater than 10 feet times the peak flow
resulting from the 1 -inch per hour rainfall runoff from their watershed, as
calculated using the rational method. The level spreaders will discharge to an
engineered filter strip at a slope of less than 5% that will be planted with grass
and maintained in perpetuity. A flow splitter will be utilized upstream of the level
spreader to bypass all flows exceeding the 1 " /hr rainfall event to an existing
natural draw.
Conclusion
Multiple BMP's located throughout the site will be utilized to accomplish the
required onsite nitrogen and phosphorous removal as well as provide peak flow
detention for the 1 -, 2 -, and 10 -year rainfall events. Nitrogen offset credits will be
purchased to mitigate the additional nitrogen export to reduce the total site
nitrogen exports to 2.2 lb/ac/yr. The onsite BMP's will serve to reduce the post -
development phosphorus export to below the allowable limit of 0.50 Ibs /ac /yr.

Methodology
• Drainage basins were delineated using 2 -foot contours for offsite areas
and 1 -foot contours onsite. Contours displayed on the drainage maps are
10 -foot and 5 -foot contours for onsite and offsite respectively to increase
readability of the maps. Onsite topography is from survey data and offsite
topography is from City of Durham Aerial Topography, 1995.
• United States Geological Survey Map is the Southwest Durham
Quadrangle.
• The FEMA Map associated with the site is Map # 3720076900J, effective
date May 2, 2006, Panel 0769J.
• Peak flows are determined using the NRCS Method, as described in TR -20,
in HydroCAD Version 7.1. NRCS Curve Numbers are based upon cover
condition and soil type as described below.
• Soil data to determine curve numbers in the watershed are from USDA
Durham County Soil Map # 33.
• Cover conditions for each watershed was determined based on digital
maps obtained from the City of Durham, survey information, aerial
photography.
• Time of concentration calculations were determined using the TR -55
method for sheet flow, shallow concentrated flow, lake flow, and channel
flow
• The routing analysis for the dry pond was accomplished using HydroCAD
Version 7.1 which utilizes the storage- indication method.

Preliminary BMP Sizing Calculations

1 121 - WQ #1 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #1 - Required Surface Area
Drainage Area to Basin = 12.88 acres
Impervious Area to Basin = 6.65 acres
Impervious Percentage = 520
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 5070
Site % impervious 527o
Upper Boundary 6070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
2.06
2.06
2.06
2.12
2.12
2.12
2.40
2.40
2.40
SA /DA = 2.12
Surface Area Required = 11,869 sf
Surface Area Provided = 31,407 sf
Matt Jones, El
1/25/2012
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ# 1 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #1 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Runoff Volume
Simple Me
Drainage Area (A) = 12.88
Impervious Area = 6.65
Impervious Fraction (IA) = 0.52
Rainfall Depth (RD) = 1.00
Rv = 0.51
Storage = KS *Stageb
KS = 31083.00
b = 1.0755
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 24063 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.79
Contour
Average
360.79
ft
Contour
361.00
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(co
360.0
0.0
31407
0
0
0
362.0
2.0
34265
32836
65672
65672
364.0
4.0
37174
35720
71439
137111
366.0
6.0
40156
38665
77330
214441
Runoff Volume
Simple Me
Drainage Area (A) = 12.88
Impervious Area = 6.65
Impervious Fraction (IA) = 0.52
Rainfall Depth (RD) = 1.00
Rv = 0.51
Storage = KS *Stageb
KS = 31083.00
b = 1.0755
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 24063 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.79
ft
Elevation Required to Detain WQ Volume =
360.79
ft
Actual Orifice Elevation =
361.00
ft
Temporary Pool Volume Provided = 31083 cf
Temporary Pool Surface Area Provided = 33430 sf
Matt Jones, El
1/25/2012

1121 - WQ #1 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #1 - Drawdown Orifice Sizing
Orifice Diameter=
2.50 in
Area of Orifice =
0.03 sf
Orifice Invert =
360.00 ft
KS =
31083.00
b =
1.0755
CD=
0.6
CW =
3.0
g =
32.2 ft /s2
Matt Jones, El
1/25/2012
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
361.00
31083
0.155
360.91
28143
0.148
0.151
2940
19415
360.82
25225
0.139
0.143
2918
20358
360.74
22330
0.130
0.135
2895
21476
360.65
19461
0.121
0.126
2869
22829
360.56
16622
0.111
0.116
2839
24519
360.47
13816
0.099
0.105
2805
26717
360.38
11050
0.087
0.093
2766
29755
360.29
8333
0.072
0.079
2718
34383
360.21
5677
0.058
0.065
2656
40901
360.12
3108
0.025
0.042
2569
61498
Step Increment = 0.09 ft
End Goal = 3108.30 cf
Maximum Orifice Flow = 0.15 cfs
Drawdown Time = 3.49 days

1 121 - WQ #2 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #2 - Required Surface Area
Drainage Area to Basin = 38.3 acres
Impervious Area to Basin = 19.02 acres
Impervious Percentage = 50%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 407o
Site % impervious 5070
Upper Boundary 5070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.73
1.73
1.73
2.05
2.05
2.05
2.06
2.06
2.06
SA /DA = 2.05
Surface Area Required = 34,181 sf
Surface Area Provided = 56,196 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #2 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #2 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 38.30
Impervious Area = 19.02
Impervious Fraction (IA) = 0.50
Rainfall Depth (RD) = 1.00
Rv = 0.50
Storage = KS *Stageb
KS = 54496.00
b = 1 1.1156
thod
Acres
Acres
Inch
(Rv = 0.05 +0.9 *IA
Runoff Volume (V) = 1 69090 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.24 ft
Contour
Average
Actual Orifice Elevation =
371.30 ft
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(so
(so
(co
(cf)
370.0
0.0
56196
0
0
0
372.0
2.0
62949
59573
119145
119145
374.0
4.0
69996
66473
132945
252090
376.0
6.0
77340
73668
147336
399426
378.0
8.0
84981
81161
162321
561747
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 38.30
Impervious Area = 19.02
Impervious Fraction (IA) = 0.50
Rainfall Depth (RD) = 1.00
Rv = 0.50
Storage = KS *Stageb
KS = 54496.00
b = 1 1.1156
thod
Acres
Acres
Inch
(Rv = 0.05 +0.9 *IA
Runoff Volume (V) = 1 69090 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.24 ft
Elevation Required to Detain WQ Volume =
371.24 ft
Actual Orifice Elevation =
371.30 ft
Temporary Pool Volume Provided = 73026 cf
Temporary Pool Surface Area Provided = 62668 sf
Matt Jones, El
11/16/2011

1 121 - WQ #2 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #2 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
4.00 in
0.09 sf
370.00 ft
54496.00
1.1156
0.6
3.0
32.2 ft /s`
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
371.30
73026
0.447
371.19
65951
0.424
0.436
7076
16235
371.07
58953
0.400
0.412
6998
16978
370.96
52040
0.374
0.387
6913
17858
370.85
45222
0.346
0.360
6819
18928
370.73
38508
0.316
0.331
6713
20270
370.62
31915
0.283
0.299
6594
22027
370.51
25460
0.245
0.264
6455
24487
370.39
19172
0.199
0.222
6288
28320
370.28
13094
0.147
0.173
6078
35087
370.17
7303
0.067
0.107
5791
54112
Step Increment = 0.11 ft
End Goal = 7302.64 cf
Maximum Orifice Flow = 0.44 cfs
Drawdown Time = 2.94 days

1 121 - WQ #3 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #3 - Required Surface Area
Drainage Area to Basin = 3.21 acres
Impervious Area to Basin = 1.59 acres
Impervious Percentage = 50%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 407o
Site % impervious 5070
Upper Boundary 5070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.73
1.73
1.73
2.04
2.04
2.04
2.06
2.06
2.06
SA /DA = 2.04
Surface Area Required = 2,859 sf
Surface Area Provided = 7,336 sf
Matt Jones, El
1/25/2012
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual. Julv 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #3 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #3 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0
Stage (ft)
Runoff Volume
Simple Mi
Drainage Area (A) = 3.21
Impervious Area = 1.59
Impervious Fraction (IA) = 0.50
Rainfall Depth (RD) = 1.00
Rv = 0.50
Storage = KS *Stageb
KS = 7218.10
b = 1.1237
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 5777 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.82
Contour
Average
398.82
ft
Contour
398.90
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(co
398.0
0.0
7336
0
0
0
400.0
2.0
8457
7897
15793
15793
402.0
4.0
9643
9050
18100
33893
404.0
6.0
10896
10270
20539
54432
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0
Stage (ft)
Runoff Volume
Simple Mi
Drainage Area (A) = 3.21
Impervious Area = 1.59
Impervious Fraction (IA) = 0.50
Rainfall Depth (RD) = 1.00
Rv = 0.50
Storage = KS *Stageb
KS = 7218.10
b = 1.1237
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 5777 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.82
ft
Elevation Required to Detain WQ Volume =
398.82
ft
Actual Orifice Elevation =
398.90
ft
Temporary Pool Volume Provided = 6412 cf
Temporary Pool Surface Area Provided = 8006 sf
Matt Jones, El
1/25/2012

1 121 - WQ #3 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #3 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
1.00 in
0.01 sf
398.00 ft
7218.10
1.1237
0.6
3.0
32.2 ft /s`
Matt Jones, El
1/25/2012
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
398.90
6412
0.024
398.82
5788
0.023
0.024
624
26270
398.74
5171
0.022
0.023
617
27303
398.66
4562
0.021
0.021
609
28501
398.59
3962
0.019
0.020
600
29918
398.51
3372
0.018
0.019
590
31631
398.43
2793
0.016
0.017
579
33769
398.35
2227
0.015
0.015
566
36554
398.27
1677
0.013
0.014
550
40421
398.19
1146
0.010
0.011
531
46398
398.12
641
0.007
0.009
504
57912
Step Increment = 0.08 ft
End Goal = 641.22 cf
Maximum Orifice Flow = 0.02 cfs
Drawdown Time = 4.15 days

1 121 - WQ #4 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #4 - Required Surface Area
Drainage Area to Basin = 3.85 acres
Impervious Area to Basin = 1.75 acres
Impervious Percentage = 45%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 407o
Site % impervious 457o
Upper Boundary 5070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.73
1.73
1.73
1.91
1.91
1.91
2.06
2.06
2.06
SA /DA = 1.91
Surface Area Required = 3,203 sf
Surface Area Provided = 10,490 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #4 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #4 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Storage Volume
Runoff Volume
Simple Mi
Drainage Area (A) = 3.85
Impervious Area = 1.75
Impervious Fraction (IA) = 0.45
Rainfall Depth (RD) = 1.00
Rv = 0.46
Storage = KS *Stageb
KS = 10568.00
b = 1 1.2184
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 6416 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.66
Contour
Average
384.66
ft
Contour
384.70
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(cf)
384.0
0.0
10490
0
0
0
386.0
2.0
14238
12364
24728
24728
388.0
4.0
17408
15823
31646
56374
390.0
6.0
20893
19151
38301
94675
Storage Volume
Runoff Volume
Simple Mi
Drainage Area (A) = 3.85
Impervious Area = 1.75
Impervious Fraction (IA) = 0.45
Rainfall Depth (RD) = 1.00
Rv = 0.46
Storage = KS *Stageb
KS = 10568.00
b = 1 1.2184
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 6416 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.66
ft
Elevation Required to Detain WQ Volume =
384.66
ft
Actual Orifice Elevation =
384.70
ft
Temporary Pool Volume Provided = 6843 cf
Temporary Pool Surface Area Provided = 11911 sf
Matt Jones, El
11/16/2011

1 121 - WQ #4 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #4 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
1.00 in
0.01 sf
384.00 ft
10568.00
1.2184
0.6
3.0
32.2 ft /s`
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
384.70
6843
0.021
384.64
6142
0.020
0.021
701
33680
384.58
5455
0.019
0.020
687
34686
384.52
4783
0.018
0.019
672
35844
384.46
4128
0.017
0.018
655
37202
384.40
3491
0.016
0.016
637
38828
384.34
2874
0.014
0.015
617
40835
384.28
2280
0.013
0.014
594
43417
384.22
1713
0.011
0.012
567
46947
384.17
1178
0.009
0.010
535
52290
384.11
684
0.007
0.008
494
62194
Step Increment = 0.06 ft
End Goal = 684.32 cf
Maximum Orifice Flow = 0.02 cfs
Drawdown Time = 4.93 days

1 121 - WQ #5 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #5 - Required Surface Area
Drainage Area to Basin = 18.3 acres
Impervious Area to Basin = 8.68 acres
Impervious Percentage = 47%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 407o
Site % impervious 4776
Upper Boundary 5070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.73
1.73
1.73
1.98
1.98
1.98
2.06
2.06
2.06
SA /DA = 1.98
Surface Area Required = 15,746 sf
Surface Area Provided = 25,756 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #5 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #5 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 18.30
Impervious Area = 8.68
Impervious Fraction (IA) = 0.47
Rainfall Depth (RD) = 1.00
Rv = 0.48
Storage = KS *Stageb
KS = 25747.00
b = 1 1.0955
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 31679 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.21
Contour
Average
375.21
ft
Contour
375.30
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(cf)
374.0
0.0
25756
0
0
0
376.0
2.0
29559
27658
55315
55315
378.0
4.0
32514
31037
62073
117388
380.0
6.0
35551
34033
68065
185453
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 18.30
Impervious Area = 8.68
Impervious Fraction (IA) = 0.47
Rainfall Depth (RD) = 1.00
Rv = 0.48
Storage = KS *Stageb
KS = 25747.00
b = 1 1.0955
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 31679 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.21
ft
Elevation Required to Detain WQ Volume =
375.21
ft
Actual Orifice Elevation =
375.30
ft
Temporary Pool Volume Provided = 34320 cf
Temporary Pool Surface Area Provided = 28921 sf
Matt Jones, El
11/16/2011

1 121 - WQ #5 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #5 - Drawdown Orifice Sizing
Orifice Diameter=
2.50 in
Area of Orifice =
0.03 sf
Orifice Invert =
374.00 ft
KS =
25747.00
b =
1.0955
CD=
0.6
CW =
3.0
g =
32.2 ft /s2
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
375.30
34320
0.179
375.19
31034
0.171
0.175
3286
18767
375.07
27778
0.161
0.166
3256
19604
374.96
24555
0.152
0.157
3223
20588
374.84
21369
0.141
0.146
3186
21767
374.73
18224
0.130
0.135
3145
23219
374.62
15125
0.117
0.124
3099
25075
374.50
12081
0.103
0.110
3044
27574
374.39
9104
0.087
0.095
2978
31225
374.27
6210
0.067
0.077
2894
37402
374.16
3432
0.040
0.054
2777
51900
Step Increment = 0.11 ft
End Goal = 3432.03 cf
Maximum Orifice Flow = 0.18 cfs
Drawdown Time = 3.21 days

1 121 - WQ #6 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #6 - Required Surface Area
Drainage Area to Basin = 5.05 acres
Impervious Area to Basin = 2.55 acres
Impervious Percentage = 50%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 5070
Site % impervious 5070
Upper Boundary 6070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
2.06
2.06
2.06
2.08
2.08
2.08
2.40
2.40
2.40
SA /DA = 2.08
Surface Area Required = 4,569 sf
Surface Area Provided = 5,211 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #6 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
Matt Jones, El
11/16/2011
1121 - Del Webb
WQ #6 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage Volume
Runoff Volume
Simple M4
Drainage Area (A) = 5.05
Impervious Area = 2.55
Impervious Fraction (IA) = 0.50
Rainfall Depth (RD) = 1.00
Rv = 0.50
Storage = KS *Stageb
KS = 5767.90
b = 1.3464
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9 *IA)
Runoff Volume (V) = 1 9247 cf (V = 3630 *Rp *Rv*A
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.42
Contour
Average
383.42
ft
Contour
383.50
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(cf)
(cf)
382.0
0.0
5211
0
0
0
384.0
2.0
9455
7333
14666
14666
386.0
4.0
13170
11313
22625
37291
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage Volume
Runoff Volume
Simple M4
Drainage Area (A) = 5.05
Impervious Area = 2.55
Impervious Fraction (IA) = 0.50
Rainfall Depth (RD) = 1.00
Rv = 0.50
Storage = KS *Stageb
KS = 5767.90
b = 1.3464
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9 *IA)
Runoff Volume (V) = 1 9247 cf (V = 3630 *Rp *Rv*A
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.42
ft
Elevation Required to Detain WQ Volume =
383.42
ft
Actual Orifice Elevation =
383.50
ft
Temporary Pool Volume Provided = 9957 cf
Temporary Pool Surface Area Provided = 8937 sf

1 121 - WQ #6 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #6 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
1.00 in
0.01 sf
382.00 ft
5767.90
1.3464
0.6
3.0
32.2 ft /s`
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
383.50
9957
0.032
383.38
8874
0.030
0.031
1082
34877
383.25
7825
0.029
0.030
1049
35409
383.13
6811
0.027
0.028
1014
36008
383.01
5834
0.026
0.027
977
36694
382.89
4898
0.024
0.025
936
37490
382.76
4006
0.022
0.023
892
38436
382.64
3162
0.020
0.021
844
39596
382.52
2373
0.018
0.019
789
41078
382.39
1647
0.016
0.017
726
43104
382.27
996
0.013
0.014
651
46206
Step Increment = 0.12 ft
End Goal = 995.65 cf
Maximum Orifice Flow = 0.03 cfs
Drawdown Time = 4.50 days

1 121 - LS #7 Sizing.xls
Level Spreader Flow and Length
1121 - Del Webb
LS #7 Calculations
Composite C Value Calculation
Matt Jones, El
11/16/2011
Cover Condition
C Value
E92
Portion of Total Area
Weighted C Value
Impervious (Streets)
0.95
0.58
0.55
Open HSG 'D'
0.35
0.42
0.15
Total 2.21
Total 0.70
Composite C Value = 0.70
1 in /hr Ratinal Flow Calculation
Intensity = 1.00 in /hr
Rational Flow Equation
Q=C xIxA cfs
Q = 0.70 x 1.00 x 2.21 = 1.55 cfs
Total Flow to Level Spreader = 1.55 cfs
Level Spreader Length Calculations
Level Spreader Length Multiplier = 10 ft /cfs
Length of Level Spreader Required = 15 ft
Length of Level Spreader Provided = 50 ft

1121 - Del Webb
Level Spreader #7 Flow Splitter
Peak Flow =
1.55
cfs
Pipe to Level Spreader Invert =
390.00
feet
WSE =
390.90
feet
Diameter of Pipe to Level Spreader =
8.00
inches
Discharge Coefficient (Cd) =
0.60
g =
32.20
ft /s /s
Submerged Area (a) = 0.35 ft2
Effective Head (h) = 0.90 feet
Q = Cd *a *�2 *g *h
Orifice Flow (Q) = 1 1.59 cfs
Bypass Weir Elevation = 390.90

1 121 - WQ #8 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #8 - Required Surface Area
Drainage Area to Basin = 29.2 acres
Impervious Area to Basin = 17.33 acres
Impervious Percentage = 59%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 5070
Site % impervious 5970
Upper Boundary 6070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
2.06
2.06
2.06
2.38
2.38
2.38
2.40
2.40
2.40
SA /DA = 2.38
Surface Area Required = 30,245 sf
Surface Area Provided = 61,138 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #8 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #8 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 29.20
Impervious Area = 17.33
Impervious Fraction (IA) = 0.59
Rainfall Depth (RD) = 1.00
Rv = 0.58
Storage = KS *Stageb
KS = 60508.00
b = 1 1.0953
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 61917 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.02
Contour
Average
359.02
ft
Contour
359.10
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(cf)
358.0
0.0
61319
0
0
0
360.0
2.0
68377
64848
129696
129696
362.0
4.0
75754
72066
144131
273827
364.0
6.0
83441
79598
159195
433022
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 29.20
Impervious Area = 17.33
Impervious Fraction (IA) = 0.59
Rainfall Depth (RD) = 1.00
Rv = 0.58
Storage = KS *Stageb
KS = 60508.00
b = 1 1.0953
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 61917 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.02
ft
Elevation Required to Detain WQ Volume =
359.02
ft
Actual Orifice Elevation =
359.10
ft
Temporary Pool Volume Provided = 67166 cf
Temporary Pool Surface Area Provided = 66879 sf
Matt Jones, El
11/16/2011

1 121 - WQ #8 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #8 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
4.00 in
0.09 sf
358.00 ft
60508.00
1.0953
0.6
3.0
32.2 ft /s`
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
359.10
67166
0.406
359.00
60736
0.384
0.395
6430
16272
358.91
54365
0.362
0.373
6371
17084
358.81
48058
0.337
0.349
6307
18055
358.71
41822
0.311
0.324
6235
19248
358.62
35667
0.282
0.296
6155
20766
358.52
29603
0.250
0.266
6064
22795
358.42
23646
0.213
0.232
5957
25723
358.33
17818
0.187
0.200
5828
29096
358.23
12153
0.111
0.149
5664
37961
358.13
6717
0.049
0.080
5437
67845
Step Increment = 0.10 ft
End Goal = 6716.61 cf
Maximum Orifice Flow = 0.40 cfs
Drawdown Time = 3.18 days

1 121 - WQ #9 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #9 - Required Surface Area
Drainage Area to Basin = 49.95 acres
Impervious Area to Basin = 23.82 acres
Impervious Percentage = 48%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 407o
Site % impervious 487o
Upper Boundary 5070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.73
1.73
1.73
1.98
1.98
1.98
2.06
2.06
2.06
SA /DA = 1.98
Surface Area Required = 43,162 sf
Surface Area Provided = 101,403 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1121 - WQ #9 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #9 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Contour
Elevation
(ft)
Stage
(ft)
Contour
Surface
Area
(sf)
Average
Contour
Surface Area
(sf)
Incremental
Volume
(cf)
Cumulative
Volume
(cf)
410.0
0.0
101403
0
0
0
412.0
2.0
109678
105541
211081
211081
414.0
4.0
118237
113958
227915
438996
416.0
6.0
127073
122655
245310
684306
418.0
8.0
136174
131624
263247
947553
4200 .
10.0
1 145534
1 140854
1 281708
1 1229261
422.0
1 12.0
1 151151
1 148343
1 296685
1 1525946
Storage Volume
Storage = KS *Stageb
KS = 96578.00
b = 1.1028
Runoff Volume (V) = 1 86886 cf (V = 3630 *Rp *Rv *A)
Water Quality Volume Stacie Calculation
Stage Required to Detain WQ Volume = 0.91 ft
Elevation Required to Detain WQ Volume = 410.91 ft
Actual Orifice Elevation = 411.00 ft
Temporary Pool Volume Provided = 96578 cf
Temporary Pool Surface Area Provided = 106506 sf
Matt Jones, El
11/16/2011
Runoff Volume
Simple Method
Drainage Area (A)
= 49.95 Acres
Impervious Area
= 23.82 Acres
Impervious Fraction (IA)
= 0.48
Rainfall Depth (RD)
= 1.00 Inch
Rv=
0.48 (Rv = 0.05 +0.9 *IA)
Runoff Volume (V) = 1 86886 cf (V = 3630 *Rp *Rv *A)
Water Quality Volume Stacie Calculation
Stage Required to Detain WQ Volume = 0.91 ft
Elevation Required to Detain WQ Volume = 410.91 ft
Actual Orifice Elevation = 411.00 ft
Temporary Pool Volume Provided = 96578 cf
Temporary Pool Surface Area Provided = 106506 sf
Matt Jones, El
11/16/2011

1 121 - WQ #9 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #9 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
5.00 in
0.14 sf
410.00 ft
96578.00
1.1028
0.6
3.0
32.2 ft /s`
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
411.00
96578
0.584
410.91
87291
0.551
0.568
9287
16365
410.82
78095
0.515
0.533
9196
17247
410.74
68999
0.477
0.496
9096
18322
410.65
60013
0.436
0.457
8985
19671
410.56
51152
0.390
0.413
8861
21442
410.47
42432
0.339
0.365
8720
23921
410.39
33877
0.301
0.320
8555
26764
410.30
25521
0.205
0.253
8356
33083
410.21
17416
0.122
0.163
8105
49702
410.12
9658
0.055
0.088
7758
88073
Step Increment = 0.09 ft
End Goal = 9657.80 cf
Maximum Orifice Flow = 0.57 cfs
Drawdown Time = 3.64 days

1 121 - WQ #10 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #10 - Required Surface Area
Drainage Area to Basin = 15.99 acres
Impervious Area to Basin = 7.58 acres
Impervious Percentage = 47%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 407o
Site % impervious 4776
Upper Boundary 5070
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.73
1.73
1.73
1.97
1.97
1.97
2.06
2.06
2.06
SA /DA = 1.97
Surface Area Required = 13,752 sf
Surface Area Provided = 24,297 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ# 10 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #10 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 15.99
Impervious Area = 7.58
Impervious Fraction (IA) = 0.47
Rainfall Depth (RD) = 1.00
Rv = 0.48
Storage = KS *Stageb
KS = 23859.00
b = 1 1.1779
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 27666 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.13
Contour
Average
389.13
ft
Contour
389.20
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(cf)
388.0
0.0
24297
0
0
0
390.0
2.0
29985
27141
54282
54282
392.0
4.0
36051
33018
66036
120318
394.0
6.0
42414
39233
78465
198783
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 15.99
Impervious Area = 7.58
Impervious Fraction (IA) = 0.47
Rainfall Depth (RD) = 1.00
Rv = 0.48
Storage = KS *Stageb
KS = 23859.00
b = 1 1.1779
-thod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 27666 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.13
ft
Elevation Required to Detain WQ Volume =
389.13
ft
Actual Orifice Elevation =
389.20
ft
Temporary Pool Volume Provided = 29575 cf
Temporary Pool Surface Area Provided = 29030 sf
Matt Jones, El
11/16/2011

1 121 - WQ #10 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #10 - Drawdown Orifice Sizing
Orifice Diameter=
2.50 in
Area of Orifice =
0.03 sf
Orifice Invert =
388.00 ft
KS =
23859.00
b =
1.1 779
CD=
0.6
CW =
3.0
g =
32.2 ft /s2
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
389.20
29575
0.172
389.10
26608
0.164
0.168
2967
17694
388.99
23690
0.155
0.159
2918
18329
388.89
20826
0.146
0.150
2864
19069
388.79
18020
0.136
0.141
2806
19948
388.68
15278
0.125
0.130
2741
21021
388.58
12610
0.113
0.119
2669
22375
388.48
10024
0.100
0.107
2586
24171
388.38
7536
0.086
0.093
2488
26744
388.27
5168
0.067
0.076
2368
30957
388.17
2957
0.044
0.056
2211
39765
Step Increment = 0.10 ft
End Goal = 2957.47 cf
Maximum Orifice Flow = 0.17 cfs
Drawdown Time = 2.78 days

1 121 - WQ #11 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #11 - Required Surface Area
Drainage Area to Basin = 23.41 acres
Impervious Area to Basin = 7.86 acres
Impervious Percentage = 340
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 307o
Site % impervious 347o
Upper Boundary 407o
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.34
1.34
1.34
1.48
1.48
1.48
1.73
1.73
1.73
SA /DA = 1.48
Surface Area Required = 15,086 sf
Surface Area Provided = 56,558 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ# 1 1 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #11 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 23.41
Impervious Area = 7.86
Impervious Fraction (IA) = 0.34
Rainfall Depth (RD) = 1.00
Rv = 0.35
Storage = KS *Stageb
KS = 55851.00
b = 1 1.0874
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 29928 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.56
Contour
Average
392.56
ft
Contour
392.60
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(cf)
392.0
0.0
56558
0
0
0
394.0
2.0
62475
59517
119033
119033
396.0
4.0
68657
65566
131132
250165
398.0
6.0
75104
71881
143761
393926
Storage Volume
Runoff Volume
Simple Me
Drainage Area (A) = 23.41
Impervious Area = 7.86
Impervious Fraction (IA) = 0.34
Rainfall Depth (RD) = 1.00
Rv = 0.35
Storage = KS *Stageb
KS = 55851.00
b = 1 1.0874
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 29928 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
0.56
ft
Elevation Required to Detain WQ Volume =
392.56
ft
Actual Orifice Elevation =
392.60
ft
Temporary Pool Volume Provided = 32047 cf
Temporary Pool Surface Area Provided = 58081 sf
Matt Jones, El
11/16/2011

1121 - WQ #11 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #10 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
3.00 in
0.05 sf
392.00 ft
55851.00
1.0874
0.6
3.0
32.2 ft /s`
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
392.60
32047
0.163
392.55
28994
0.154
0.158
3053
19296
392.49
25966
0.144
0.149
3028
20372
392.44
22967
0.133
0.138
3000
21684
392.39
19998
0.121
0.127
2968
23334
392.34
17065
0.109
0.115
2933
25505
392.28
14172
0.094
0.101
2893
28554
392.23
11326
0.083
0.089
2846
32148
392.18
8537
0.056
0.070
2789
40067
392.12
5820
0.033
0.045
2717
60814
392.07
3205
0.015
0.024
2615
109689
Step Increment = 0.05 ft
End Goal = 3204.74 cf
Maximum Orifice Flow = 0.16 cfs
Drawdown Time = 4.42 days

1 121 - WQ #12 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #12 - Required Surface Area
Drainage Area to Basin = 9.12 acres
Impervious Area to Basin = 3.56 acres
Impervious Percentage = 39%
Avereage Depth (Volume /SA) = 3.00 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 307o
Site % impervious 397o
Upper Boundary 407o
Average Depth (Vol /SA) (ft)
3.0 3.0 3.0
1.34
1.34
1.34
1.69
1.69
1.69
1.73
1.73
1.73
SA /DA = 1.69
Surface Area Required = 6,723 sf
Surface Area Provided = 11,806 sf
Matt Jones, El
11/16/2011
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ# 12 Sizing.xls
Above NP Volume
Normal Pool
Top of Berm
1121 - Del Webb
WQ #12 - Above Normal Pool Volume
Storage Volume
Stage /Storage Calculations
Storage Volume
Runoff Volume
Simple Mi
Drainage Area (A) = 9.12
Impervious Area = 3.56
Impervious Fraction (IA) = 0.39
Rainfall Depth (RD) = 1.00
Rv = 0.40
Storage = KS *Stageb
KS = 11566.00
b = 1 1.2072
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 13286 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.12
Contour
Average
403.12
ft
Contour
403.20
ft
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(co
(cf)
402.0
0.0
11805
0
0
0
404.0
2.0
15072
13439
26877
26877
406.0
4.0
18637
16855
33709
60586
408.0
6.0
22483
20560
41120
101706
Storage Volume
Runoff Volume
Simple Mi
Drainage Area (A) = 9.12
Impervious Area = 3.56
Impervious Fraction (IA) = 0.39
Rainfall Depth (RD) = 1.00
Rv = 0.40
Storage = KS *Stageb
KS = 11566.00
b = 1 1.2072
Ahod
Acres
Acres
Inch
(Rv = 0.05 +0.9* IA)
Runoff Volume (V) = 1 13286 cf (V = 3630 *Rp *Rv*A)
Water Quality Volume Stage Calculation
Stage Required to Detain WQ Volume =
1.12
ft
Elevation Required to Detain WQ Volume =
403.12
ft
Actual Orifice Elevation =
403.20
ft
Temporary Pool Volume Provided = 14414 cf
Temporary Pool Surface Area Provided = 14500 sf
Matt Jones, El
11/16/2011

1 121 - WQ #12 Sizing.xls
Drawdown Orifice Sizing
1121 - Del Webb
WQ #12 - Drawdown Orifice Sizing
Orifice Diameter=
Area of Orifice =
Orifice Invert =
KS =
b=
CD=
CW _
g=
1.50 in
0.01 sf
402.00 ft
11566.00
1.2072
0.6
3.0
32.2 ft /s`
Matt Jones, El
11/16/2011
Water
Surface
Elevation
(ft)
Volume
Stored
(cf)
Incremental
Orifice Flow
(cfs)
Average
Orifice Flow
(cfs)
Incremental
Volume Drawn
Down
(cfs)
Incremental
Time
(s)
403.20
14414
0.063
403.10
12945
0.060
0.062
1468
23847
403.00
11505
0.057
0.059
1440
24577
402.89
10095
0.054
0.055
1410
25416
402.79
8718
0.050
0.052
1377
26399
402.69
7378
0.047
0.049
1340
27575
402.59
6078
0.043
0.045
1300
29022
402.48
4825
0.038
0.041
1253
30878
402.38
3626
0.033
0.036
1199
33401
402.28
2491
0.028
0.031
1134
37183
402.18
1441
0.020
0.024
1050
44050
Step Increment = 0.10 ft
End Goal = 1441.35 cf
Maximum Orifice Flow = 0.06 cfs
Drawdown Time = 3.50 days

1 121 - WQ #14 Sizing
WQ Volume
1121 - Del Webb
WQ #14 Water Quality Volume
Runoff Volume
Simple Method
Drainage Area (A) = 46.22 Acres
Impervious Fraction (IA) = 0.50
Rainfall Depth (RD) = 1.00 Inch
Rv= 0.50 (Rv = 0.05 +0.9 *IA)
Runoff Volume (V) = 83889 cf (V = 3630 *Rp *Rv*A)
Matt Jones, El
5/29/2012

Required Maps and Information

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SOIL DATA IS FROM USDA Q L MAP
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SOIL SURVEY FOR DURHAM 0 250 500 1000 Z F °�'�112,
COUNTY, SHEET NUMBER 33 SMl SCALE: 1" =500'
SCALE: 1"= 500' S M I
QOOPYAA>lii 2007 TM DOMWDff AND THE DEM ARE THE PR0PERi1' OF HOWAEH ASSOm Es, PA ANY REPROOL 110H NT Mff PRIOR M4dT1E}E CONSENT IB PROHMM

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1. . . ......... . II . . . ....... . ..... .... I11Itif1IFII11II............ I. .................. . ..... I1FitIIIIII....... .. . 1. . ......... Ir itIk- 1foft 00 low IS H EET FLOW
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AREA\7 63.1.7-A itII-,PAT
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II1IIekit 1III 47-F . . ......... I. . ... . ..... PROPERTY �T PATH
tLINE (TY SHALLOW FLOW I II1TC PATH LENGTH 75' 11 eCH 0 100 61�NEL FIL W ........ . ... -LENGTH 750'
IitTr­ PATH
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LENGTH
270
ILOinto, TC PATH -oft
tIItSHE 41W
49 L
IP,
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LAKi
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IILENGTH 600' dCHANNELFLOW
'LENGTH.
H ANN EL-FILO TQ(DP#
............... IZI-E XC . .....
O [)P#2
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LENGTH 341't
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IW
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.... .... ...
it. ........
ATED kQW T PATH
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LENGTH 425�
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II........... . III�PRE-DEVELOPMENT DRAINAGE MAP 0 200 400 Boo
SCALE: I" � 400' SCALE: 1"� 400'
0
@COPYRIGHT 2008 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
HORVATH
A S S 0 C I A T E S
16 CONSULTANT PLACE,SUITIE 201
DURHAM, NORTH CAROLINA 27707
P 919A90.4990 F 919A90.8953
537 MARKET STREET, SUITE LL20
CHATTAN OOGA, TE NN ESSE E 37402
P 423.266A990 F 423.266.5700
www.horvathassociates.com
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SCALE: 1"� 400'
@COPYRIGHT 2008 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
HORVATH
A S S 0 C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919A90.4990 F 919A90.8953
537 MARKET STREET, SUITE LL20
CHATTAN OOGA, TE NN ESSE E 37402
P 423.266A990 F 423.266.5700
www.horvathassociates.com
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HORVATH
A S S O C I A T E S
16 CONSULTANT PLACE, SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
537 MARKET STREET, SUITE LL20
CHATTANOOGA, TENNESSEE 37402
P 423.266.4990 F 423.266.5700
www.horvathassociates.com
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HORVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
537 MARKET STREET, SUITE LL20
CHATTAN OOGA, TE NN ESSE E 37402
P 423.266.4990 F 423.266.5700
www.horvathassociates.com
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POST-
DEVELOPMENT
DRAINGAGE
MAP #2
11/17/2011
1 I 1 ST SITE PLAN REVIEW I mi
1/26/2012
2ND SITE PLAN REVIEW I MJ
DRAWN BY: CHECKED BY:
MLJ
DATE
8-4-2011
SCALE
1 200'
PROJECT NO.
1121
SHEET NO.
S
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11/17/2011
1 I 1 ST SITE PLAN REVIEW I mi
1/26/2012
2ND SITE PLAN REVIEW I MJ
DRAWN BY: CHECKED BY:
MLJ
DATE
8-4-2011
SCALE
1 200'
PROJECT NO.
1121
SHEET NO.
S
W4

-Wt -I-
Prepared for: Randy King - Pulte Homes
1225 Crescent Green Drive - Suite 250
Cary, NC 27518
[phone]

Table of Contents
Narrative
WQ# 1 Summary and Calculations
WQ #2 Summary and Calculations
DP #3 Summary
WQ #4 Summary and Calculations
HydroCAD Runoff Analysis
HydroCAD 100 -Year Analysis (Clogged Orifices)
Drainage Maps

Narrative

Del Webb
BMP Design
General Description
Del Webb will be an approximately 296 -acre community south of Leesville Road
east of the intersection with Doc Nichols Road. The entire project is in the Neuse
river basin and the majority of the site is not in a watershed protection district.
There are multiple streams located onsite and FEMA 100 -year floodplain is
associated with a few reaches.
The development for the site will consist of residential homes, a clubhouse area,
and associated streets and parking. The community will be a residential
development. The calculations included in this analysis are for the first phase of
the development.
Water Quality Ponds
There are three water quality ponds that will be constructed in association with
the first phase of the development; they are labeled WQ# 1, WQ #2, and WQ #3.
Each pond is designed to completely detain the water quality runoff volume
from its contributing drainage area in the temporary pool. The temporary pool
in each pond will draw down over a period of 2 -5 days by means of a low flow
orifice located in a siphon that will be installed in the riser. A larger orifice is set in
the riser of each pond at the temporary pool to bypass larger storm events.
There is one drainage point of interest for the discharge from the water quality
ponds, DP #1. All three ponds work in conjunction to keep the post -
development peak flow rate at DP# 1 below the pre - development rate for the
1 -, 2 -, and 10 -year rainfall events. The runoff from each pond will be discharged
to a level spreader. Each level spreader is designed so that it's length is 10 feet
for every 1 cfs of flow directed to it. WQ Ponds # 1 and #2 have flow splitters
downstream of the principal spillway pipes that will limit the flow to the level
spreaders. All flows in excess of what the level spreader can handle will be
directed to a bypass pipe by means of an overflow weir in the flow splitter. The
outlet structure for WQ #4 is designed with a closed top so that only the flow
entering the riser through the orifices located in the riser wall will be directed to
the level spreader.
Dry Pond #3
There is one dry pond proposed for the site to attenuate the peak flow rate at
DP #7 in the post - development condition. The pond will utilize a siphon with a
low flow orifice to limit the peak flow during the 1 -year rainfall event to below
the pre - development rate at DP #7. A larger orifice will be installed in the riser to

limit the flows during the 2- and 10 -year rainfall events to below the pre -
development rate. All runoff up to and including that resulting from the 10 -year
rainfall event will be directed to a level spreader downstream of the PSP. Flows
from larger storm events will bypass the riser, which has a closed top, by means
of an emergency spillway cut into existing grade.
Runoff Analysis
The original runoff analysis presented in the SIA was amended for the Post -
Development Analysis for Phase I. To determine the runoff rates at DP# 1, the
areas that originally contributed to DP #1 that had runoff area removed from
them to be directed to the WQ ponds were revised, but all other drainage areas
were left unchanged. The areas that changed were labeled TO DP #1 PRE, TO
DP #3 PRE, TO DP #5 PRE and TO DP #6 PRE in the pre - development analysis in the
SIA. The drainage areas for the ponds and the ponds themselves were then
added to the analysis to calculate the post - development runoff rates for the
drainage point of interest, DP #1.

Methodology
• Drainage areas were delineated using 2 -foot contours for offsite areas
and 1 -foot contours onsite. Onsite topography is from survey data and
offsite topography is from City of Durham Aerial Topography, 1995.
• United States Geological Survey Map is the Southwest Durham
Quadrangle.
• The FEMA Map associated with the site is Map # 3720076900J, effective
date May 2, 2006, Panel 0769J.
• Peak flows are determined using the NRCS Method, as described in TR -20,
in HydroCAD Version 7.1. NRCS Curve Numbers are based upon cover
condition and soil type as described below.
• Soil data to determine curve numbers in the watershed are from USDA
Durham County Soil Map # 33.
• Cover conditions for each watershed was determined based on digital
maps obtained from the City of Durham, survey information, aerial
photography.
• Time of concentration calculations were determined using the TR -55
method for sheet flow, shallow concentrated flow, lake flow, and channel
flow
• The routing analysis for the ponds was accomplished using HydroCAD
Version 7.1 which utilizes the storage- indication method.

WQ #1 Summary and Calculations

DURHAM
City of Durham
Public Works Department
Stormwater Services Divisions
1 B 6 9 101 City Hall Plaza, Durham, North Carolina, 27701
crrr OF MEDIcINE Telephone [phone] FAX [phone]
Wet Detention Pond Design Summary
Stormwater Management Construction Plan Review:
A complete stormwater management construction plan submittal includes a design summary for each
stormwater BMP, design calculations, plans and specifications showing BMP, inlet and outlet structure details.
I. PROJECT INFORMATION
Project Name: Del Webb - Duraleigh Arbors Phase 1
PIN: 0769 -03 -41 -8938 Case #: D1100150
Design Contact Person: Matt Jones Phone #: ( 919 ) 490 -4990
Legal Name of Owner: Pulte Group
Owner Contact: Randy King Phone #: ( 919 ) 816 - 1100
Owner Address: 1225 Crescent Green Drive - suite 250, Cary NC
Deed Book Page # or Plat Book Page# for BMP Property
For projects with multiple basins, specify which pond this worksh et applies to: WQ 41
Does the proposed pond also incorporate stormwater detention. Yes No
Detention provided for: X 1 -year X 2 -year x 10 -year other
Dam Height: 12.3 (feet) Dam Classification: A
Elevations
Pond bottom elevation
Permanent pool elevation
Temporary pool elevation
1 -year storm orifice /weir elevation
1 -year storm water surface elevation
2 -year storm orifice /weir elevation
2 -year storm water surface elevation
10 -year storm orifice /weir elevation
10 -year storm water surface elev.
Emergency spillway elevation
Top of embankment/dam
Maximum water surface elevation
Areas
Permanent pool area provided
Minimum required permanent pool area
Design storm surface area
Drainage area (10 -acres min)
352.00
ft.
(floor of the pond)
358.00
ft.
(invert elevation of the orifice)
359.60
ft.
(elevation of the structure overflow)
359.60
ft.
(invert elevation)
360.12
ft.
359.60
ft.
(invert elevation)
360.47
ft.
359.60
ft.
(invert elevation)
362.27
ft.
363 .00
ft.
(invert of emergency spillway)
365.38 (Settledit.
(elevation)
363.89
ft.
(max. storm pond can safely pass)
22, 7 6 4
ft
(water surface area at orifice invert
elevation)
18,403
ft
(calculated surface area required)
34,460
ft
(Specif frequency event: 10 year)
25.90
ac.
(total drainage to the pond

Discharges (Speck only applicable frequency events)
At BMP
At Analysis Point(s) that BMP Contributes to
1 -year
Pre - development 315.36 cfs
Post - development w/o detention 512.41 cfs
With detention 312.27 CfS
Volumes
Permanent pool volume
Water quality pool storage volume
Design storm storage volume
Total Storage volume provided at design storm
Total Storage volume provided at top of dam
Forebay volume
2 -year
1 -year
10 -year -year
2 -year
10 -year
708.99 CfS
-year
Inflow
49.69
Cfs
66 .7 4
cfs
125.68
CfS
Cfs
Routed outflow
1.54
cfs
3.28
cfs
8.93
cfs
cfs
At Analysis Point(s) that BMP Contributes to
1 -year
Pre - development 315.36 cfs
Post - development w/o detention 512.41 cfs
With detention 312.27 CfS
Volumes
Permanent pool volume
Water quality pool storage volume
Design storm storage volume
Total Storage volume provided at design storm
Total Storage volume provided at top of dam
Forebay volume
2 -year
10 -year -year
466.41 CfS
1059.27 CfS cfs
708.99 CfS
1399.58 CfS cfs
463.04 CfS
1052.03 CfS Cfs
77,743
ft3
(volume of main pond and forebay)
44,264
ft3
(volume above permanent pool)
131,430
ft3
(volume above permanent pool)
209,173
ft3
345,418
ft3
17,319
ft3
( 20% of permanent pool volume)
Hydraulic Depths
Volume of normal pool divided by surface area of normal pool 3.42 ft.
Volumes at temporary pool plus normal pool divided by surface area of temporary pool 4.01 ft.
Other Parameters
SA/DA' 1.63 (from DWQ table)
Diameter of orifice 3.0 in. (must provide draw down over 2 to S day period)
Draw -down time 75.12 hrs
' When using the SA/DA tables from the Stormwater Best Management Practices Manual, linear interpolation may be used for values
between table entries.
Riser /Principal and Emerge,
1 -year storm orifice /weir
2 -year storm orifice /weir
10 -year storm orifice /weir
25 - year storm orifice /weir
Principal spillway
Emergency spillway
icy Spillway It
diameter_
diameter_
diameter_
diameter
diameter
width 52
iform,
1s
48
18
ft.
ztion
in. length ft.
in. length ft.
in. length ft.
in. length ft.
in.
side slopes 5 :1 slope 0 %

II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements. Initial in the space provided to indicate the following
design requirements have been met and supporting documentation is attached.
Applicant's initials
MLJ a. The permanent pool depth is between 3- and 6 -feet (required minimum hydraulic depth of 3-
feet).
MLJ b. The forebay volume is approximately equal to 20% of the pond volume.
MLJ c. The temporary pool controls runoff for water quality design storm.
MLJ d. The temporary pool draws down in 2- to 5 -days.
MLJ e. The drainage area to the facility is at least 10- acres.
MLJ f. Riprap outlet protection, if provided, reduces flow to non - erosive velocities (provide
calculations).
MLJ g. The pond length to width ratio is greater than or equal to 3:1.
MLJ h. The pond side slopes above the permanent pool area are no steeper than 3:1.
MLJ i. A submerged and vegetated shelf with a slope no greater than 6:1 is provided around the
perimeter of the pond (show on plan and profile and provide a vegetation plan).
MLJ J. Vegetative cover above the permanent pool elevation is specified. No woody vegetation is
permitted on the embankment.
MLJ k. A surface baffle, trash rack or similar device is provided for both the overflow and orifice.
Flat top trash racks are not acceptable. Access hatch has been provided.
MLJ 1. A recorded drainage easement is provided for each pond including access to the nearest
right -of -way and is graded per Section 8.3, Stormwater Control Facilities (BMPs).
MLJ m. If the basin is used for sediment and erosion control during construction, a note requiring
clean out and vegetative cover being established prior to use as a wet detention basin shall be
provided on the construction plan.
MLJ n. A mechanism is specified which will drain the pond for maintenance and emergencies.
Valves used shall be plug valves.
MLJ o. Anti - floatation calculations are provided for riser structure.
MLJ p. A plan view of the pond with grading shown is provided.
MLJ q. A profile through the forebay, main pond and spillway is provided. Water surface
elevations are shown on the profile.
MLJ r. Riser structure details are provided.
MLJ s. Dam designed to account for a 5.00% settlement factor.
MLJ t. Compaction specifications for the embankment are shown on the plan.
MLJ u. The minimum top of dam width has been provided for the pond embankment top width per
Section 8.3, Stormwater Control Facilities (BMPs).
Note: Executed Stormwater Facility Operation and Maintenance Permit Agreement, payment of permit
fee per facility and payment of surety are required prior to construction drawing approval.

1 121 - WQ# 1 Sizing.xls
Surface Area Calcs (85% TSS)
1121 - Del Webb
WQ #1 - Required Surface Area
Drainage Area to Basin = 25.90 acres
Impervious Area to Basin = 10.57 acres
Impervious Percentage = 41%
Pond Volume Provided = 77743
Surface Area at Normal Pool = 22764
Avereage Depth (Volume /SA) = 3.42 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 40%
Site % impervious 41%
Upper Boundary 50%
Average Depth (Vol /SA) (ft)
3.0 3.4 4.0
1.73
1.61
1.43
1.76
1.63
1.45
2.06
1.92
1.73
SA /DA = 1.63
Surface Area Required = 18,403 sf
Surface Area Provided = 22,764 sf
Matt Jones, El
4/24/2012
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual. July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #1 Sizing.xls
Below NP Volumes
Matt Jones, El
4/24/2012
1121 - Del Webb
Wet Detention Basin #1 Below Normal Pool Volumes
Forebay Bottom
Main Pool Bottom
Forebay Volume
Stage /Storage Calculations
Forebay Volume = 17319 cf
Main Pool Volume
Stage /Storage Calculations
Contour
Average
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(cf)
(cf)
352.0
0.0
1329
0
0
0
357.5
5.5
4084
2707
14886
14886
358.0
6.0
5647
4866
2433
17319
Forebay Volume = 17319 cf
Main Pool Volume
Stage /Storage Calculations
Main Pool Volume = 60425 cf
Total Pond Volume
Forebay Volume = 17319 cf
Main Pool Volume = 60425 cf
Total Pond Voume = 77743 cf
Forebay Percentage of Total Volume = 22.28%
Contour
Average
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(cf)
(cf)
352.0
0.0
6491
0
0
0
357.5
5.5
12842
9667
53166
53166
358.0
6.0
16194
14518
7259
60425
Main Pool Volume = 60425 cf
Total Pond Volume
Forebay Volume = 17319 cf
Main Pool Volume = 60425 cf
Total Pond Voume = 77743 cf
Forebay Percentage of Total Volume = 22.28%

1121 - WQ #1 Sizing.xls
WQ Volume
1121 - Del Webb
WQ #1 - Above Normal Pool Volume
Runoff Volume
Simple Method
Drainage Area (A) =
25.90
Acres
Impervious Area =
10.57
Acres
Impervious Fraction (IA) =
0.41
Rainfall Depth (RD) =
1.00
Inch
Rv=
0.42
(Rv = 0.05 +0.9 *IA)
Runoff Volume (V) = 39233 cf (V = 3630 *Rp *Rv*A)
Normal Pool Elevation = 358.00
Temporary Pool Elevation = 359.60
Temporary Pool Volume = 44264 cf
Matt Jones, El
4/24/2012

1 121 - WQ #1 Sizing.xls
Drawdown Orifice Sizing
Matt Jones, El
4/24/2012
1121 - Del Webb
Drawdown Orifice Sizing
3
30,453
22,700
0.6
m
3,5.2 Orifice Equation
3..5.2.1 Drawdown Titne Calculations for a Pond with can Orafice Outlet
M
Stormwater Management Manual
For the specific case where At = A,, and II = 0
#
* *g [(2 , fiiyrz +; I1llrrs
G:rl cx

1121 - WQ #1 Sizing.xls
Flow Splitter
1121 - Del Webb
WQ #1 - Flow Spliffer Calcs
Orifice Flow
Desired Flow to Level Spreader =
7.00
cfs
Level Spreader Lip Elevation =
354.00
feet
Pipe to LS Invert =
353.60
feet
Bypass Weir Elevation =
355.60
feet
Diameter of Orifice =
15.00
inches
Discharge Coefficient (Cd) = 0.60
g = 32.20 ft /s /s
Submerged Area (a) = 1.23 ft2
Effective Head (h) = 1.38 feet
Q = Cd *a *�2 *g *h
Orifice Flow (Q) = 6.93 cfs
Matt Jones, El
4/24/2012

1 121 - WQ #1 Sizing.xls
Anti Float Calcs
Extended Base- NC Products
Manhole Riser /Barrel Anti - Flotation Calculation Sheet
1 121 - WO# 1 Riser
Matt Jones, El
4/24/2012
Input Data =_>
Invert of Extended Base =
353,25
feet
Riser Crest Elevation =
362,30
feet
Invert of Outlet Barrel =
354,50
Inside diameter of manhole
= 4,0
feet
Wall thickness of manhole
= 5,0
inches
Outside diameter of manhole riser sections
= 4,83
feet
Diameter of Extended base Pad =
6,0
feet
Height of Extended Base Pad
= 1 0,50
Ifeet
Inside Barrel diameter =
18,0
inches
Barrel Wall Thickness =
3,25
inches
Outside Diameter of Barrel =
24,50
inches
Diameter of 1 st Inlet
= 8,0
inches
Diameter of 2nd Inlet
= 1 4,0
lincheS2
Diameter of 3rd Inlet
= 15,0
inches2
Weight of Structure =_>
Volume of Riser Walls =
49.43
cf
Volume of Extended Base Pad =
14.14
cf
Total Volume of Concrete =
63.57
cf
Opening for barrel
= 1.364
cf
Opening for 1 st inlet orifice
= 0.145
cf
Opening for 2nd inlet orifice
= 0.036
cf
Opening for 3rd inlet orifice
= 0.511
cf
Total Volume of Openings in Concrete =
2.057
cf
Total Concrete in Riser Section Minus Openings =
61.51
cf
Depth of Concrete Fill Layer =
0.75
ft
Volume of Concrete in Fill Layer =
9.42
cf
Total Volume of Concrete Present in Riser =
70.94
cf
Concrete unit weight
= 1 142
lb/cf (From NC Products Catalog)
Total Weight of Concrete = 10073 Ibs
Amount of water displaced =_>
Volume of Water Displaced by Riser Structure = 171.01 cf
Volume of Water Displaced by Trash Rack = 26 cf
Total Volume of Water Displaced = 1 97.01 cf
Unit Weight of water = 62 Ib /cf
Weight of water displaced = 12293 Ibs
Determine if Anti - Flotation Block is Required =_>
Safety factor to use = 1.25 (recommend 1.25 or higher)
Actual Safety Factor = 0.82 Safety Factor Unacceptable
Antiflotation Block Calculations
Width of Antiflotation Block (Square) = 7.00 ft
Height of Antiflotation Block = 0.75 ft
Weight of Antiflotation Block = 5219 Ibs
Weight of Structure and Antiflotation Block = 15291
Actual Safety Factor = 1.24 Safety Factor Acceptable

1 121 - POND OUTLET VELOCITY DISSIPATOR DESIGN.xIs Matt Jones, El
W Q # 1 4/24/2012
Velocity Dissipator Calculations w/ PIPES.EXE
NRCD Land Quality Section - Pipe Design
Entering the following values will provide you with the expected outlet
velocity and depth of flow in a pipe, assuming the Mannings roughness
number is constant over the entire length of the pipe.
25 -Year Outflow, Q (cfs) = 33.00 Flow Depth (ft.) 1.50
Slope, S (%) = 1.00 Velocity, V (ft /s) 18.67
Pipe Dia., D (in.) = 18
Manning's n Value = 0.013
NRCD Land Quality Section
NYDOT Dissipator Design Results
Pipe Dia., Do (ft.) = 1.50
Outlet Velocity, Vo (fps) = 1 8.67
Apron Length, LA (ft.) = 12.0 ZONE 3
Average Dia. Stone Thickness
(inches) Class (inches)
4 A 12
8 B 18
>> 10 1 24 <<
14 2 36
Width,W = 0.4 *LA + Do Thickness = 1.5 * DMAX
Width, W = 6.3 ft.
SAY: 7.0 ft.
FINAL DIMENSIONS:
Length, L (ft.) = 12.0
Width, W (ft.) = 7.0
Depth, D (in.) = 24 (NCDENR Erosion & Sed. Cont. Manual §8.06.6)
Stone Class = 1 ( NCDOT Std. §1042)
*Cells in red denote required inputs from PIPES.exe outputs

WQ #2 Summary and Calculations

DURHAM
City of Durham
Public Works Department
Stormwater Services Divisions
1 B 6 9 101 City Hall Plaza, Durham, North Carolina, 27701
crrr OF MEDIcINE Telephone [phone] FAX [phone]
Wet Detention Pond Design Summary
Stormwater Management Construction Plan Review:
A complete stormwater management construction plan submittal includes a design summary for each
stormwater BMP, design calculations, plans and specifications showing BMP, inlet and outlet structure details.
I. PROJECT INFORMATION
Project Name: Del Webb - Duraleigh Arbors Phase 1
PIN: 0769 -03 -41 -8938 Case #: D1100150
Design Contact Person: Matt Jones Phone #: ( 919 ) 490 -4990
Legal Name of Owner: Pulte Group
Owner Contact: Randy King Phone #: ( 919 ) 816 - 1100
Owner Address: 1225 Crescent Green Drive - suite 250, Cary NC
Deed Book Page # or Plat Book Page# for BMP Property
For projects with multiple basins, specify which pond this worksh et applies to: WQ 42
Does the proposed pond also incorporate stormwater detention. Yes No
Detention provided for: X 1 -year X 2 -year x 10 -year other
Dam Height: 10.0 (feet) Dam Classification: A
Elevations
Pond bottom elevation
Permanent pool elevation
Temporary pool elevation
1 -year storm orifice /weir elevation
1 -year storm water surface elevation
2 -year storm orifice /weir elevation
2 -year storm water surface elevation
10 -year storm orifice /weir elevation
10 -year storm water surface elev.
Emergency spillway elevation
Top of embankment/dam
Maximum water surface elevation
Areas
Permanent pool area provided
Minimum required permanent pool area
Design storm surface area
Drainage area (10 -acres min)
367.00
ft.
(floor of the pond)
371.00
ft.
(invert elevation of the orifice)
372.40
ft.
(elevation of the structure overflow)
372.40
ft.
(invert elevation)
373.22
ft.
372.40
ft.
(invert elevation)
373.66
ft.
372.40
ft.
(invert elevation)
375.39
ft
376 .10
ft.
(invert of emergency spillway)
379.35 settled ft.
(elevation)
377.58
ft.
(max. storm pond can safely pass)
64, 5 5 9
ft
(water surface area at orifice invert
elevation)
43,260
ft
(calculated surface area required)
79,592
ft
(Specif frequency event: 10 year)
52.79
ac.
(total drainage to the pond

Discharges (Speck only applicable frequency events)
At BMP
1 -year
2 -year
10 -year
-year
Inflow 137.50 cfs
175.88 cfs
302.90 cfs
cfs
Routed outflow 5.37 cfs
9.80 cfs
29.15 cfs
cfs
At Analysis Point(s) that BMP Contributes to
1 -year
Pre - development 315.36 cfs
Post - development w/o detention 512.41 cfs
With detention 312.27 cfs
Volumes
Permanent pool volume
Water quality pool storage volume
Design storm storage volume
Total Storage volume provided at design storm
Total Storage volume provided at top of dam
Forebay volume
2 -year
ft3
10 -year
331, 602
-year
466.41
CfS
1059.27
CfS
cfs
708.99
CfS
1399.58
CfS
cfs
463.04
CfS
1052.03
CfS
cfs
219,752 ft3 (volume of main pond and forebay)
99, 76 5
ft3
(volume above permanent pool)
331, 602
ft3
(volume above permanent pool)
551,354
ft3
931,416
ft3
46,031
ft3
( 20% of permanent pool volume)
Hydraulic Depths
Volume of normal pool divided by surface area of normal pool 3.40 ft.
Volumes at temporary pool plus normal pool divided by surface area of temporary pool 3.20 ft.
Other Parameters
SA/DA' 1.88 (from DWQ table)
Diameter of orifice 4.0 in. (must provide draw down over 2 to S day period)
Draw -down time 106 .32 hrs
' When using the SA/DA tables from the Stormwater Best Management Practices Manual, linear interpolation may be used for values
between table entries.
Riser /Principal and Emerge,
1 -year storm orifice /weir
2 -year storm orifice /weir
10 -year storm orifice /weir
25 - year storm orifice /weir
Principal spillway
Emergency spillway
icy Spillway It
diameter_
diameter_
diameter_
diameter
diameter
width 6 0
formation
in.
in.
in.
60 in.
36 in.
ft.
length 212 ft.
length - ft.
length - ft.
length ft.
side slopes 5 :1 slope 0 %

II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements. Initial in the space provided to indicate the following
design requirements have been met and supporting documentation is attached.
Applicant's initials
MLJ a. The permanent pool depth is between 3- and 6 -feet (required minimum hydraulic depth of 3-
feet).
MLJ b. The forebay volume is approximately equal to 20% of the pond volume.
MLJ c. The temporary pool controls runoff for water quality design storm.
MLJ d. The temporary pool draws down in 2- to 5 -days.
MLJ e. The drainage area to the facility is at least 10- acres.
MLJ f. Riprap outlet protection, if provided, reduces flow to non - erosive velocities (provide
calculations).
MLJ g. The pond length to width ratio is greater than or equal to 3:1.
MLJ h. The pond side slopes above the permanent pool area are no steeper than 3:1.
MLJ i. A submerged and vegetated shelf with a slope no greater than 6:1 is provided around the
perimeter of the pond (show on plan and profile and provide a vegetation plan).
MLJ J. Vegetative cover above the permanent pool elevation is specified. No woody vegetation is
permitted on the embankment.
MLJ k. A surface baffle, trash rack or similar device is provided for both the overflow and orifice.
Flat top trash racks are not acceptable. Access hatch has been provided.
MLJ 1. A recorded drainage easement is provided for each pond including access to the nearest
right -of -way and is graded per Section 8.3, Stormwater Control Facilities (BMPs).
MLJ m. If the basin is used for sediment and erosion control during construction, a note requiring
clean out and vegetative cover being established prior to use as a wet detention basin shall be
provided on the construction plan.
MLJ n. A mechanism is specified which will drain the pond for maintenance and emergencies.
Valves used shall be plug valves.
MLJ o. Anti - floatation calculations are provided for riser structure.
MLJ p. A plan view of the pond with grading shown is provided.
MLJ q. A profile through the forebay, main pond and spillway is provided. Water surface
elevations are shown on the profile.
MLJ r. Riser structure details are provided.
MLJ s. Dam designed to account for a 5.00% settlement factor.
MLJ t. Compaction specifications for the embankment are shown on the plan.
MLJ u. The minimum top of dam width has been provided for the pond embankment top width per
Section 8.3, Stormwater Control Facilities (BMPs).
Note: Executed Stormwater Facility Operation and Maintenance Permit Agreement, payment of permit
fee per facility and payment of surety are required prior to construction drawing approval.

1 121 - WQ #2 Sizing.xls
Surface Area Calcs (85 %TSS)
1121 - Del Webb
WQ #2 - Required Surface Area
Drainage Area to Basin = 52.79 acres
Impervious Area to Basin = 25.64 acres
Impervious Percentage = 49%
Avereage Depth (Volume /SA) = 3.40 ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 407o
Site % impervious 497o
Upper Boundary 5070
Average Depth (Vol /SA) (ft)
3.0 3.4 4.0
1.73
1.61
1.43
2.01
1.88
1.69
2.06
1.93
1.73
SA /DA = 1.88
Surface Area Required = 43,260 sf
Surface Area Provided = 64,559 sf
Matt Jones, El
4/24/2012
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual, July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #2 Sizing.xls
Below NP Volumes
Forebay Bottom
Forebay Bottom
Main Pool Bottom
1121 - Del Webb
WQ #2 Below Normal Pool Volumes
Forebay 1 Volume
Stage /Storage Calculations
Forebay Volume = 41026 cf
Forebay 2 Volume
Stage /Storage Calculations
Contour
Average
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(so
(so
(cf)
(cf)
367.0
1 0.0
1 8618
1 0
1 0
1 0
370.5
3.5
11351
9985
34946
34946
371.0
4.0
12968
12160
6080
41026
Forebay Volume = 41026 cf
Forebay 2 Volume
Stage /Storage Calculations
Forebay Volume = 5006 cf
Main Pool Volume
Stage /Storage Calculations
Contour
Average
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(so
(so
(cf)
(cf)
367.0
1 0.0
1 617
1 0
1 0
1 0
370.5
3.5
1679
1148
4018
4018
371.0
4.0
2272
1976
988
5006
Forebay Volume = 5006 cf
Main Pool Volume
Stage /Storage Calculations
Main Pool Volume = 173721 cf
Total Pond Volume
Forebay Volume = 1 46031 cf
Main Pool Volume = 1 173721 cf
Total Pond Voume = 219752 cf
Forebay Percentage of Total Volume = 20.95%
Matt Jones, El
4/24/2012
Contour
Average
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(so
(so
(cf)
(cf)
367.0
1 0.0
1 39853
1 0
1 0
1 0
370.5
3.5
45824
42839
149935
149935
371.0
4.0
49319
47572
23786
173721
Main Pool Volume = 173721 cf
Total Pond Volume
Forebay Volume = 1 46031 cf
Main Pool Volume = 1 173721 cf
Total Pond Voume = 219752 cf
Forebay Percentage of Total Volume = 20.95%
Matt Jones, El
4/24/2012

1 121 - WQ #2 Sizing.xls
WQ Volume
1121 - Del Webb
WQ #2 - Above Normal Pool Volume
Runoff Volume
Simple Method
Drainage Area (A) =
52.79
Acres
Impervious Area =
25.64
Acres
Impervious Fraction (IA) =
0.49
Rainfall Depth (RD) =
1.00
Inch
Rv=
0.49
(Rv = 0.05 +0.9 *IA)
Runoff Volume (V) = 93347 cf (V = 3630 *Rp *Rv*A)
Normal Pool Elevation = 371.00
Temporary Pool Elevation = 372.40
Temporary Pool Volume = 99765 cf
Matt Jones, El
4/24/2012

1121 - Del Webb
WQ #2 - Drawdown Orifice Sizing
4
74,603
64,559
0.6
1.4
3,5.2 Orifice Equation
3..5.2.1 Drawdown Titne Calculations for a Pond with can Orafice Outlet
M
Stormwater Management Manual
For the specific case where At = A,, and II = 0
GCd a L

1 121 - WQ #2 Sizing.xls
Flow Splitter
1121 - Del Webb
WQ #2 - Flow Spliffer Calcs
Orifice Flow
Desired Flow to Level Spreader =
10.00
cfs
Level Spreader Lip Elevation =
366.00
feet
Pipe to LS Invert =
365.90
feet
Bypass Weir Elevation =
369.40
feet
Diameter of Orifice =
15.00
inches
Discharge Coefficient (Cd) =
0.60
g = 32.20 ft /s /s
Submerged Area (a) = 1.23 ft2
Effective Head (h) = 2.88 feet
Q = Cd *a *�2 *g *h
Orifice Flow (Q) = 10.02 cfs
Matt Jones, El
4/24/2012

1 121 - WQ #2 Sizing.xls
Anti Flotation Calculations
Extended Base- NC Products
Manhole Riser /Barrel Anti - Flotation Calculation Sheet
1 121 - WO #2 Riser
Matt Jones, El
4/24/2012
Input Data =_>
Invert of Extended Base =
361,00
feet
Riser Crest Elevation =
375,30
feet
Invert of Outlet Barrel =
367,00
Inside diameter of manhole
= 5,0
feet
Wall thickness of manhole
= 6,0
inches
Outside diameter of manhole riser sections
= 6.00
feet
Diameter of Extended base Pad =
7,2
feet
Height of Extended Base Pad
= 1 0,67
Ifeet
Inside Barrel diameter =
36,0
inches
Barrel Wall Thickness =
3,25
inches
Outside Diameter of Barrel =
42,50
inches
Diameter of 1 st Inlet
= 4,0
inches
Area of 2nd Inlet
=1 4,0
Ifeet2
Weight of Structure =_>
Volume of Riser Walls =
cf
Volume of Extended Base Pad =
M14468
cf
Total Volume of Concrete =
cf
Opening for barrel
= 4.926
cf
Opening for 1 st inlet orifice
= 0.044
cf
Opening for 2nd inlet orifice
= 2.000
cf
Total Volume of Openings in Concrete =
6.969
cf
Total Concrete in Riser Section Minus Openings =
137.71 cf
Depth of Concrete Fill Layer =
5.33
cf
Volume of Concrete in Fill Layer =
104.72
cf
Total Volume of Concrete Present in Riser =
242.43
cf
Concrete unit weight
= 142
lb/cf (From NC Products Catalog)
Total Weight of Concrete = 34425 Ibs
Amount of water displaced =_>
Volume of Water Displaced by Riser Structure = 412.37 cf
Volume of Water Displaced by Trash Rack = 26 cf
Total Volume of Water Displaced = 438.37 cf
Unit Weight of water = 62 Ib /cf
Weight of water displaced = 27354 Ibs
Determine if Anti - Flotation Block is Required =_>
Safety factor to use = 1.25 (recommend 1.25 or higher)
Actual Safety Factor = 1.26 Factor of Safety is Acceptable

1 121 - POND OUTLET VELOCITY DISSIPATOR DESIGN.xIs Matt Jones, El
WQ #2 4/24/2012
Velocity Dissipator Calculations w/ PIPES.EXE
NRCD Land Quality Section - Pipe Design
Entering the following values will provide you with the expected outlet
velocity and depth of flow in a pipe, assuming the Mannings roughness
number is constant over the entire length of the pipe.
25 -Year Outflow, Q (cfs) = 80.00 Flow Depth (ft.) 3.00
Slope, S (%) = 1.00 Velocity, V (ft /s) 11.33
Pipe Dia., D (in.) = 36
Manning's n Value = 0.013
NRCD Land Quality Section
NYDOT Dissipator Design Results
Pipe Dia., Do (ft.) = 3.00
Outlet Velocity, Vo (fps) = 11.33
Apron Length, LA (ft.) = 24.0 ZONE 3
Average Dia. Stone Thickness
(inches) Class (inches)
4 A 12
8 B 18
>> 10 1 24 <<
14 2 36
Width,W = 0.4 *LA + Do Thickness = 1.5 * DMAX
Width, W = 12.6 ft.
SAY: 13.0 ft.
FINAL DIMENSIONS:
Length, L (ft.) = 24.0
Width, W (ft.) = 13.0
Depth, D (in.) = 24 (NCDENR Erosion & Sed. Cont. Manual §8.06.6)
Stone Class = 1 ( NCDOT Std. §1042)
*Cells in red denote required inputs from PIPES.exe outputs

DP #3 Summary and Calculations

DURHAM
City of Durham
Public Works Department
Stormwater Services Divisions
1 B 6 9 101 City Hall Plaza, Durham, North Carolina, 27701
crrr OF MEDIcINE Telephone [phone] FAX [phone]
Dry Detention Basin Design Summary
Stormwater Management Construction Plan Review:
A complete stormwater management construction plan submittal includes a design summary for each
stormwater BMP, design calculations, plans and specifications showing BMP, inlet and outlet structure details.
I. PROJECT INFORMATION
Project Name: Del Webb - Duraleigh Arbors Phase 1
PIN: 0769 -03 -41 -8938 Case #: D1100150
Design Contact Person: Matt Jones Phone #: (919 ) 490 -4990
Legal Name of Owner:Pulte Group
Owner Contact: Randy King Phone #: ( 919 ) 816 -1100
Owner Address: 1225 Crescent Green Drive - suite 250, Cary NC
Deed Book Page # or Plat Book Page# for BMP Property
For projects with multiple basins, specify which pond this worksheet applies to: DP 43
Detention provided for: X 1 -year X 2 -year x 10 -year other
Dam Height: 8.6 (feet) Dam Classification: C
Elevations
Basin bottom elevation
402.00
ft.
(1loor of the pond)
1 -year storm orifice /weir elevation
402.00
ft.
(invert elevation)
1 -year storm water surface elevation
405.09
ft.
2 -year storm orifice /weir elevation
405.00
ft.
(invert elevation)
2 -year storm water surface elevation
405.35
ft.
10 -year storm orifice /weir elevation
405.00
ft.
(invert elevation)
10 -year storm water surface elevation
406.45
ft.
Emergency spillway elevation
407.00
ft.
(invert of emergency spillway)
Top of embankment/dam
409.57 settled
ft.
(elevation)
Maximum water surface elevation
407.44
ft.
(max. storm pond can safely pass)
Areas
Design storm surface area
6767
ft2
(Sped frequency event. 10 .year)
Drainage area
3.20
ac.
(total drainage to the pond)
Volumes
Total storage volume provided at design storm 21679 ft3
Total storage volume provided at top of dam 9700 ft3
Hydraulic Depth (volume of design storm divided by surface area of design storm)
Hydraulic Depth 3.20 ft.

Discharges (Speck only applicable frequency events)
At BMP
Riser /Principal and Emerge,
1 -year storm orifice /weir
2 -year storm orifice /weir
10 -year storm orifice /weir
- year storm orifice /weir
Principal spillway
Emergency spillway
icy Spillway Inform,
diameter 2
diameter 10
diameter lo
diameter
diameter 18
width 4 0 ft.
II. REQUIRED ITEMS CHECKLIST
ztion
in.
in.
in.
in.
in.
length ft.
length ft.
length ft.
length ft.
side slopes s :1 slope 0 %
The following checklist outlines design requirements. In the space provided to indicate the following design
requirements have been met and supporting documentation is attached.
Applicant's initials
MLJ a. Riprap outlet protection, if provided, reduces flow to non - erosive velocities (provide
calculations).
MLJ b. The basin side slopes are no steeper than 3:1.
MLJ c. Vegetative cover for the basin is specified. No woody vegetation is permitted on the
embankment.
N/A closed d. A trash rack or similar device is provided for both the overflow and orifice. Flat top trash
racks are not acceptable. Access hatch has been provided.
MLJ e. A recorded drainage easement is provided for each basin including access to the nearest
right -of -way and is graded per Section 8.3, Stormwater Control Facilities (BMPs).
MLJ f. If the basin is used for sediment and erosion control during construction, a note requiring
clean out and vegetative cover being established prior to use as a dry detention basin shall be
provided on the construction plan.
MLJ g. Anti - floatation calculations are provided for riser structure.
MLJ h. A plan view of the pond with grading shown is provided.
MLJ i. A profile through the forebay, main pond and spillway is provided. Water surface
elevations are shown on the profile.
MLJ j. Riser structure details are provided.
MLJ k. Compaction specifications for the embankment are provided on the plan.
MLJ 1. Dam designed to account for a 5.00% settlement factor.
1 -year
2 -year
10 -year
-year
Inflow
9.90
cfs
12.32
cfs
20.13
cfs
cfs
Routed outflow
0.22
cfs
0.62
cfs
2.89
cfs
cfs
At Analysis
Point(s) that BMP Contributes
to
1 -year
2 -year
10 -year
-year
Pre - development
0.32
cfs
1.00
cfs
4.93
cfs
cfs
Post - development w/o detention
10-93
cfs
13.68
cfs
23 .58
cfs
cfs
With detention
0.22
cfs
0.62
cfs
2.89
cfs
cfs
Riser /Principal and Emerge,
1 -year storm orifice /weir
2 -year storm orifice /weir
10 -year storm orifice /weir
- year storm orifice /weir
Principal spillway
Emergency spillway
icy Spillway Inform,
diameter 2
diameter 10
diameter lo
diameter
diameter 18
width 4 0 ft.
II. REQUIRED ITEMS CHECKLIST
ztion
in.
in.
in.
in.
in.
length ft.
length ft.
length ft.
length ft.
side slopes s :1 slope 0 %
The following checklist outlines design requirements. In the space provided to indicate the following design
requirements have been met and supporting documentation is attached.
Applicant's initials
MLJ a. Riprap outlet protection, if provided, reduces flow to non - erosive velocities (provide
calculations).
MLJ b. The basin side slopes are no steeper than 3:1.
MLJ c. Vegetative cover for the basin is specified. No woody vegetation is permitted on the
embankment.
N/A closed d. A trash rack or similar device is provided for both the overflow and orifice. Flat top trash
racks are not acceptable. Access hatch has been provided.
MLJ e. A recorded drainage easement is provided for each basin including access to the nearest
right -of -way and is graded per Section 8.3, Stormwater Control Facilities (BMPs).
MLJ f. If the basin is used for sediment and erosion control during construction, a note requiring
clean out and vegetative cover being established prior to use as a dry detention basin shall be
provided on the construction plan.
MLJ g. Anti - floatation calculations are provided for riser structure.
MLJ h. A plan view of the pond with grading shown is provided.
MLJ i. A profile through the forebay, main pond and spillway is provided. Water surface
elevations are shown on the profile.
MLJ j. Riser structure details are provided.
MLJ k. Compaction specifications for the embankment are provided on the plan.
MLJ 1. Dam designed to account for a 5.00% settlement factor.

MLJ
m. The minimum top of dam width has been provided for the pond embankment top width per
Section 8.3, Stormwater Control Facilities (BMPs).
Note: Executed Stormwater Facility Operation and Maintenance Permit Agreement, payment of permit
fee per facility and payment of surety are required prior to construction drawing approval.

1121 - WQ#3 Riser Anti - Flotation Calcs.xls
NC Products Extended Base Riser
Input Data =_>
Extended Base- INC Products
Manhole Riser /Barrel Anti - Flotation Calculation Sheet
1 121 - WQ #3 Riser
Invert of Extended Base =
400.75
feet
Riser Top Elevation =
L102,00 09.00
feet
Invert of Outlet Barrel =
Inside diameter of manhole
= 4.0
feet
Wall thickness of manhole
= 1 5.0 linches
cf
Outside diameter of manhole riser sections
= 4.63
feet
Diameter of Extended base Pad =
b.0
feet
Height of Extended Base Pad
=1 0.50
feet
Inside Barrel diameter =
16.0
inches
Barrel Wall Thickness =
1 3.25 linches
ft
Outside Diameter of Barrel =
24.50
inches
Diameter of 1 st Inlet
=
inches
Diameter of 2nd Inlet
=
M10
inches2
Height of Flat Top
=
feet
Weight of Structure =_>
Volume of Riser Walls =
cf
Volume of Extended Base Pad =
Mcf
cf
Total Volume of Concrete =
Opening for barrel
= 1.364
cf
Opening for 1 st inlet orifice
= 0.036
cf
Opening for 2nd inlet orifice
= 0.227
cf
Opening for 3rd inlet orifice
= 0.002
cf
Total Volume of Openings in Concrete =
1.630
cf
Total Concrete in Riser Section Minus Openings =
51 .53
cf
Depth of Concrete Fill Layer =
0.75
1cf
ft
Volume of Concrete in Fill Layer =
9.42
Total Volume of Concrete Present in Riser =
60.96
cf
Concrete unit weight
= 142 lb/cf
(From NC Products Catalog)
Weight of Flat Top =
1700
Total Weight of Concrete =
10356
Ibs
Amount of water displaced =_>
Volume of Water Displaced by Riser Structure = 156.33 cf
Unit Weight of water = 62 lb/cf
Weight of water displaced = 9755 Ibs
Determine if Anti - Flotation Block is Required =_>
Safety factor to use = 1.25 (recommend 1.25 or higher)
Actual Safety Factor = 1.06 Factor of Safety is Unacceptable
Antiflotation Block Calculations
Width of Antiflotation Block (Square) = 7.00 ft
Height of Antiflotation Block = 0.67 ft
Weight of Antiflotation Block = 4641 Ibs
Weight of Structure and Antiflotation Block - 14997
Actual Safety Factor = 1.54 Safety Factor Acceptable
Matt Jones, El
4/24/2012

WQ #4 Summary and Calculations

DURHAM
City of Durham
Public Works Department
Stormwater Services Divisions
1 B 6 9 101 City Hall Plaza, Durham, North Carolina, 27701
crrr OF MEDIcINE Telephone [phone] FAX [phone]
Wet Detention Pond Design Summary
Stormwater Management Construction Plan Review:
A complete stormwater management construction plan submittal includes a design summary for each
stormwater BMP, design calculations, plans and specifications showing BMP, inlet and outlet structure details.
I. PROJECT INFORMATION
Project Name: Del Webb - Duraleigh Arbors Phase 1
PIN: 0769 -03 -41 -8938 Case #: D1100150
Design Contact Person: Matt Jones Phone #: ( 919 ) 490 -4990
Legal Name of Owner: Pulte Group
Owner Contact: Randy King Phone #: ( 919 ) 816 - 1100
Owner Address: 1225 Crescent Green Drive - Suite 250, Cary NC
Deed Book Page # or Plat Book Page# for BMP Property
For projects with multiple basins, specify which pond this worksheet applies to: WQ 44
Does the proposed pond also incorporate stormwater detention? es No
Detention provided for: x 1 -year x 2 -year 0 -year other
Dam Height: to . 8 (feet) Dam Classification: A
Elevations
Pond bottom elevation
Permanent pool elevation
Temporary pool elevation
1 -year storm orifice /weir elevation
1 -year storm water surface elevation
2 -year storm orifice /weir elevation
2 -year storm water surface elevation
10 -year storm orifice /weir elevation
10 -year storm water surface elev.
Emergency spillway elevation
Top of embankment/dam
Maximum water surface elevation
Areas
Permanent pool area provided
Minimum required permanent pool area
Design storm surface area
Drainage area (10 -acres min)
375.00
ft.
(floor of the pond)
381.00
ft.
(invert elevation of the orifice)
381.60
ft.
(elevation of the structure overflow)
3 e i-co
ft.
(invert elevation)
381.87
ft.
381.60
ft.
(invert elevation)
382.03
ft.
381.60
ft.
(invert elevation)
382.68
ft.
383 .30
ft.
(invert of emergency spillway)
385.46 Settled ft.
(elevation)
383.63
ft.
(max. storm pond can safely pass)
7,553
ft
(water surface area at orifice invert
elevation)
1, 778
ft
(calculated surface area required)
11,115
ft
(Specif frequency event' 10 year)
2.76*
ac.
(total drainage to the pond
*Drainage
area
same as approved site plan

Discharges (Speck only applicable frequency events)
At BMP
At Analysis Point(s) that BMP Contributes to
1 -year
Pre - development 315.36 cfs
Post - development w/o detention 512.41 cfs
With detention -� 12 27 cfs
Volumes
Permanent pool volume
Water quality pool storage volume
Design storm storage volume
Total Storage volume provided at design storm
Total Storage volume provided at top of dam
Forebay volume
2 -year
1 -year
2 -year
466.41
10 -year
-year
Inflow
6.86
cfs
8.84
cfs
15.44
cfs
cfs
Routed outflow
0.29
cfs
0.58
cfs
1.53
cfs
cfs
At Analysis Point(s) that BMP Contributes to
1 -year
Pre - development 315.36 cfs
Post - development w/o detention 512.41 cfs
With detention -� 12 27 cfs
Volumes
Permanent pool volume
Water quality pool storage volume
Design storm storage volume
Total Storage volume provided at design storm
Total Storage volume provided at top of dam
Forebay volume
2 -year
10 -year -year
466.41
CfS
1059.27 CfS cfs
708 .9 9
CfS
1399.58 CfS cfs
463.04
CfS
1052.03 CfS cfs
24,332
ft3
(volume of main pond and forebay)
5,228
ft3
(volume above permanent pool)
16,554
ft3
(volume above permanent pool)
40, 886
ft3
85,305
ft3
5,750
ft3
( 20% of permanent pool volume)
Hydraulic Depths
Volume of normal pool divided by surface area of normal pool 3.22 ft.
Volumes at temporary pool plus normal pool divided by surface area of temporary pool 3.06 ft.
Other Parameters
SA/DA' 1.48 (from DWQ table)
Diameter of orifice 1.5 in. (must provide draw down over 2 to S day period)
Draw -down time 77.52 hrs
1 When using the SA/DA tables from the Stormwater Best Management Practices Manual, linear interpolation may be used for values
between table entries.
Riser /Principal and Emerge,
1 -year storm orifice /weir
2 -year storm orifice /weir
10 -year storm orifice /weir
- year storm orifice /weir
Principal spillway
Emergency spillway
icy Spillway Inform,
diameter 8
diameter -
diameter -
diameter
diameter 18
width 4 8 ft.
ztion
in.
in.
in.
in.
in.
length ft.
length ft.
length ft.
length ft.
side slopes 5 :1 slope 0 %

II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements. Initial in the space provided to indicate the following
design requirements have been met and supporting documentation is attached.
Applicant's initials
MLJ a. The permanent pool depth is between 3- and 6 -feet (required minimum hydraulic depth of 3-
feet).
MLJ b. The forebay volume is approximately equal to 20% of the pond volume.
MLJ c. The temporary pool controls runoff for water quality design storm.
MLJ d. The temporary pool draws down in 2- to 5 -days.
N /A* e. The drainage area to the facility is at least 10- acres.
N/A f. Riprap outlet protection, if provided, reduces flow to non - erosive velocities (provide
calculations).
MLJ g. The pond length to width ratio is greater than or equal to 3:1.
MLJ h. The pond side slopes above the permanent pool area are no steeper than 3:1.
MLJ i. A submerged and vegetated shelf with a slope no greater than 6:1 is provided around the
perimeter of the pond (show on plan and profile and provide a vegetation plan).
MLJ J. Vegetative cover above the permanent pool elevation is specified. No woody vegetation is
permitted on the embankment.
MLJ k. A surface baffle, trash rack or similar device is provided for both the overflow and orifice.
Flat top trash racks are not acceptable. Access hatch has been provided.
MLJ 1. A recorded drainage easement is provided for each pond including access to the nearest
right -of -way and is graded per Section 8.3, Stormwater Control Facilities (BMPs).
MLJ m. If the basin is used for sediment and erosion control during construction, a note requiring
clean out and vegetative cover being established prior to use as a wet detention basin shall be
provided on the construction plan.
MLJ n. A mechanism is specified which will drain the pond for maintenance and emergencies.
Valves used shall be plug valves.
MLJ o. Anti - floatation calculations are provided for riser structure.
MLJ p. A plan view of the pond with grading shown is provided.
MLJ q. A profile through the forebay, main pond and spillway is provided. Water surface
elevations are shown on the profile.
MLJ r. Riser structure details are provided.
MLJ s. Dam designed to account for a 5.00% settlement factor.
MLJ t. Compaction specifications for the embankment are shown on the plan.
MLJ u. The minimum top of dam width has been provided for the pond embankment top width per
Section 8.3, Stormwater Control Facilities (BMPs).
Note: Executed Stormwater Facility Operation and Maintenance Permit Agreement, payment of permit
fee per facility and payment of surety are required prior to construction drawing approval.

1 121 - WQ #4 Sizing.xls
Surface Area Calcs (85% TSS)
1121 - Del Webb
WQ #4 - Required Surface Area
Drainage Area to Basin = 2.76 acres
Impervious Area to Basin = 0.97 acres
Impervious Percentage = 35%
Total Pond Volume Below NP =
24332
cf
Normal Pool Surface Area =
7553
sf
Avereage Depth (Volume /SA) =
3.22
ft
Interpolation to Determine SA /DA Ratio
Impervious
Lower Boundary 30%
Site % impervious 35%
Upper Boundary 40%
Average Depth (Vol /SA) (ft)
3.0 3.2 4.0
1.34
1.28
1.08
1.54
1.48
1.26
1.73
1.66
1.43
SA /DA = 1.48
Surface Area Required = 1,778 sf
Surface Area Provided = 7,553 sf
Matt Jones, El
4/24/2012
<- from table below
<- interpolated
<- from table below
Surface Area (SA) to Drainage Area (DA) Ratio for Permanent Pool Sizing to
Achieve 85 Percent TSS Pollutant Removal Efficiency in the Piedmont
(From NCDWQ Stormwater BMP Manual. July 20071
Percent
Impervious
Cover
3.0
Permanent Pool Average Depth (ft)
4.0 5.0 6.0 7.0 8.0
9.0
10%
0.59
0.49
0.43
0.35
0.31
0.29
0.26
20%
0.97
0.79
0.70
0.59
0.51
0.46
0.44
30%
1.34
1.08
0.97
0.83
0.70
0.64
0.62
40%
1.73
1.43
1.25
1.05
0.90
0.82
0.77
50%
2.06
1.73
1.50
1.30
1.09
1.00
0.92
60%
2.40
2.03
1.71
1.51
1.29
1.18
1.10
70%
2.88
2.40
2.07
1.79
1.54
1.35
1.26
80%
3.36
2.78
2.38
2.10
1.86
1.60
1.42
90%
3.74
3.10
2.66
2.34
2.11
1.83
1.67

1 121 - WQ #4 Sizing.xls
Below NP Volumes
Forebay Bottom
Main Pool Bottom
Matt Jones, El
4/24/2012
1121 - Del Webb
WQ #4 Below Normal Pool Volumes
Forebay Volume
Stage /Storage Calculations
Forebay Volume = 5750 cf
Main Pool Volume
Stage /Storage Calculations
Contour
Average
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(cf)
(cf)
376.0
0.0
411
0
0
0
380.5
4.5
1681
1046
4707
4707
381.0
5.0
2489
2085
1043
5750
Forebay Volume = 5750 cf
Main Pool Volume
Stage /Storage Calculations
Main Pool Volume = 18583 cf
Total Pond Volume
Forebay Volume = 5750 cf
Main Pool Volume = 18583 cf
Total Pond Voume = 24332 cf
Forebay Percentage of Total Volume = 23.63%
Contour
Average
Contour
Incremental
Cumulative
Stage
Surface
Contour
Elevation
Volume
Volume
Area
Surface Area
(ft)
(ft)
(sf)
(sf)
(cf)
(cf)
375.0
0.0
1539
0
0
0
380.5
4.5
3774
2657
11954
11954
381.0
6.0
5064
4419
6629
18583
Main Pool Volume = 18583 cf
Total Pond Volume
Forebay Volume = 5750 cf
Main Pool Volume = 18583 cf
Total Pond Voume = 24332 cf
Forebay Percentage of Total Volume = 23.63%

1 121 - WQ #4 Sizing.xls
WQ Volume
1121 - Del Webb
WQ #4 - Above Normal Pool Volume
Runoff Volume
Simple Method
Drainage Area (A) =
2.76
Acres
Impervious Area =
0.97
Acres
Impervious Fraction (IA) =
0.35
Rainfall Depth (RD) =
1.00
Inch
Rv=
0.37
(Rv = 0.05 +0.9 *IA)
Runoff Volume (V) = 3670 cf (V = 3630 *Rp *Rv*A)
Normal Pool Elevation = 381.00
Temporary Pool Elevation = 381.60
Temporary Pool Volume = 5228 cf
Matt Jones, El
4/24/2012

1121 - Del Webb
WQ #4 - Drawdown Orifice Sizing
II&I
9,654
7,
0.6
3,5.2 Orifice Equation
3..5.2.1 Drawdown Titne Calculations for a Pond with can Orafice Outlet
M
Stormwater Management Manual
For the specific case where At = A,, and II = 0
GCd a L

1 121 - WQ #4 Sizing.xls
Anti Float Calcs
Extended Base- NC Products
Manhole Riser /Barrel Anti - Flotation Calculation Sheet
1 121 - WO #4 Riser
Matt Jones, El
4/24/2012
Input Data =_>
Invert of Extended Base =
373,00
feet
Riser Top Elevation =
383,30
feet
Invert of Outlet Barrel =
37b,00
Inside diameter of manhole
= 4,0
feet
Wall thickness of manhole
= 5.0
inches
Outside diameter of manhole riser sections
= 4,83
feet
Diameter of Extended base Pad =
b,0
feet
Height of Extended Base Pad
= 1 0,50
Ifeet
Inside Barrel diameter =
18,0
inches
Barrel Wall Thickness =
3,25
inches
Outside Diameter of Barrel =
24,50
inches
Diameter of 1 st Inlet
= 4,0
inches
Diameter of 2nd Inlet
= 8,0
inches2
Height of Flat Top
= 1,0
feet
Weight of Structure =_>
Volume of Riser Walls =
50.88
cf
Volume of Extended Base Pad =
14.14
cf
Total Volume of Concrete =
65.01
cf
Opening for barrel
= 1.364
cf
Opening for 1 st inlet orifice
= 0.036
cf
Opening for 2nd inlet orifice
= 0.145
cf
Total Volume of Openings in Concrete =
1.546
cf
Total Concrete in Riser Section Minus Openings =
63.47 cf
Depth of Concrete Fill Layer =
2.50
ft
Volume of Concrete in Fill Layer =
31.42
cf
Total Volume of Concrete Present in Riser =
94.88
cf
Concrete unit weight
= 1 142
lb/cf (From NC Products Catalog)
Weight of Flat Top= 1700
Total Weight of Concrete = 15173 Ibs
Amount of water displaced =_>
Volume of Water Displaced by Riser Structure = 193.95 cf
Unit Weight of water = 62 Ib /cf
Weight of water displaced = 12102 Ibs
Determine if Anti - Flotation Block is Required =_>
Safety factor to use = 1.25 (recommend 1.25 or higher)
Actual Safety Factor = 1.25 Factor of Safety is Acceptable

HydroCAD Runoff Analysis

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 2
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Time span =0.00 -25.00 hrs, dt =0.05 hrs, 501 points
Runoff by SCS TR -20 method, UH =SCS
Reach routing by Stor- Ind +Trans method - Pond routing by Stor -Ind method
Subcatchment 1S: TO DP #1 RunoffArea= 56.960 ac Runoff Depth >0.81"
Flow Length= 3,173' Tc =23.6 min CN =72 Runoff =41.47 cfs 3.836 of
Subcatchment 2S: TO DP #3 Runoff Area= 18.590 ac Runoff Depth >0.40"
Flow Length =2,277' Tc =21.0 min CN =62 Runoff =5.06 cfs 0.617 of
Subcatchment 3S: TO WQ #2 Runoff Area = 52.790 ac Runoff Depth= 1.45"
Tc =5.0 min CN =83 Runoff = 137.50 cfs 6.364 of
Subcatchment 4S: TO WQ #1 Runoff Area = 25.900 ac Runoff Depth= 1.07"
Tc =5.0 min CN =77 Runoff =49.69 cfs 2.312 of
Subcatchment 7S: TO DP #5 Runoff Area = 92.640 ac Runoff Depth >0.76"
Flow Length= 3,614' Tc =29.0 min CN =71 Runoff =54.14 cfs 5.870 of
Subcatchment 8S: TO DP #6 RunoffArea= 77.860 ac Runoff Depth >0.71"
Flow Length= 2,455' Tc =25.3 min CN =70 Runoff =45.94 cfs 4.634 of
Subcatchment 10S: TO WQ #3 POST Runoff Area =3.200 ac Runoff Depth= 1.74"
Tc =5.0 min CN =87 Runoff =9.90 cfs 0.464 of
Subcatchment 11S: TO WQ #4 RunoffArea =2.760 ac Runoff Depth= 1.38"
Tc =5.0 min CN =82 Runoff =6.86 cfs 0.317 of
Subcatchment 15S: TO DP #4 Runoff Area = 13.150 ac Runoff Depth = 0.76"
Flow Length= 1,169' Tc =17.2 min CN =71 Runoff =10.83 cfs 0.833 of
Reach 4R: DP #4,5, &6 REACH Peak Depth =1.50' Max Vet =4.5 fps Inflow= 106.91 cfs 11.517 of
n =0.045 L= 2,375.0' S=0.0080'/' Capacity= 1,201.80 cfs Outflow =89.45 cfs 11.476 of
Pond 1PA: WQ #1 Peak EIev= 360.12' Storage= 60.484 cf Inflow =49.69 cfs 2.312 of
Outflow =1.54 cfs 1.140 of
Pond 2PA: WQ #2 Peak EIev= 373.22' Storage= 161.783 cf Inflow= 137.50 cfs 6.364 of
Outflow =5.37 cfs 3.605 of
Pond 3P: WQ #3 Peak EIev= 405.09' Storage= 13.241 cf Inflow =9.90 cfs 0.464 of
Outflow =0.22 cfs 0.214 of
Pond 7P: WQ #4 Peak EIev= 381.87' Storage =7,891 cf Inflow =6.86 cfs 0.317 of
Outflow =0.29 cfs 0.179 of
Link 3L: DP #1 Inflow= 312.27 cfs 50.160 of
Primary= 312.27 cfs 50.160 of

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 3
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Link 6L: DP #7 POST
Inflow =0.22 cfs 0.214 of
Primary=0.22 cfs 0.214 of
1 -Year Primary Outflow Imported from 1121 - POST DEVELOPMENT - DP#2 —Link 10L Inflow= 206.86 cfs 29.486 of
Primary= 206.86 cfs 29.486 of
Link 11L: DP #3
Link 13L: DP #5
Inflow =96.12 cfs 15.699 of
Primary=96.12 cfs 15.699 of
Inflow =99.40 cfs 10.683 of
Primary=99.40 cfs 10.683 of
Total Runoff Area = 343.850 ac Runoff Volume = 25.246 of Average Runoff Depth = 0.88"

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 4
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Subcatchment 1S: TO DP #1
Runoff = 41.47 cfs @ 12.19 hrs, Volume= 3.836 af, Depth> 0.81"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
9.420
55
Onsite Woods B
7.960
70
Onsite Woods C
11.290
77
Onsite Woods D
1.360
55
Offsite Woods B
0.890
70
Offsite Woods C
22.510
77
Offsite Woods D
3.530
80
Offsite Open D
56.960 72 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
12.4
75
0.0400
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.6
415
0.0720
4.3
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
4.1
1,205
0.0380
4.9
19.65
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
3.0
945
0.0060
5.3
399.05
Channel Flow,
Area= 75.0 sf Perim= 25.0' r= 3.00' n= 0.045
2.5
533
0.0020
3.6
534.69
Channel Flow,
Area= 150.0 sf Perim= 40.0' r= 3.75' n= 0.045
23.6 3,173 Total
Subcatchment 2S: TO DP #3
Runoff = 5.06 cfs @ 12.20 hrs, Volume= 0.617 af, Depth> 0.40"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
11.900 55 Onsite Woods B
4.010 70 Onsite Woods C
2.050 77 Onsite Woods D
0.630 80 Onsite Open D
18.590 62 Weighted Average

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 5
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
12.4
75
0.0400
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.7
374
0.0530
3.7
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
1.0
440
0.0780
7.0
28.15
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
5.9
1,388
0.0080
3.9
78.72
Channel Flow,
Area= 20.0 sf Perim= 13.0' r= 1.54' n= 0.045
21.0 2,277 Total
Subcatchment 3S: TO WQ #2
Runoff = 137.50 cfs @ 11.96 hrs, Volume= 6.364 af, Depth= 1.45"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
25.640 98 Impervious
15.030 74 >75% Grass cover, Good, HSG C
12.120 61 >75% Grass cover. Good. HSG B
52.790 83 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 4S: TO WQ #1
Runoff = 49.69 cfs @ 11.96 hrs, Volume= 2.312 af, Depth= 1.07"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
10.570 98 Impervious
14.150 61 >75% Grass cover, Good, HSG B
1.180 74 >75% Grass cover, Good, HSG C
25.900 77 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 6
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Subcatchment 7S: TO DP #5
Runoff = 54.14 cfs @ 12.27 hrs, Volume= 5.870 af, Depth> 0.76"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
9.950
55
Onsite Woods B
0.000
70
Onsite Woods C
10.600
77
Onsite Woods D
0.700
61
Onsite Open B
0.000
74
Onsite Open C
9.880
80
Onsite Open D
8.410
55
Offsite Woods B
27.310
70
Offsite Woods C
7.570
77
Offsite Woods D
0.330
61
Offsite Open B
10.370
74
Offsite Open C
7.520
80
Offsite Open D
92.640
71
Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
16.3
75
0.0200
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.7
354
0.0450
3.4
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
2.0
600
0.0400
5.0
20.16
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
1.2
341
0.0260
4.8
28.83
Channel Flow,
Area= 6.0 sf Perim= 7.0' r= 0.86' n= 0.045
4.3
1,310
0.0210
5.1
60.85
Channel Flow,
Area= 12.0 sf Perim= 11.0' r= 1.09' n= 0.045
3.5
934
0.0100
4.4
88.02
Channel Flow,
Area= 20.0 sf Perim= 13.0' r= 1.54' n= 0.045
29.0 3,614 Total
Subcatchment 8S: TO DP #6
Runoff = 45.94 cfs @ 12.22 hrs, Volume= 4.634 af, Depth> 0.71"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type 11 24 -hr 1 -Year Rainfall= 3.00"

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 7
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Area (ac)
CN
Description
4.370
55
Onsite Woods D
1.550
70
Onsite Woods C
12.050
55
Offsite Woods B
24.250
70
Offsite Woods C
27.090
77
Offsite Woods D
1.000
61
Offsite Open B
2.520
74
Offsite Open C
5.030
80
Offsite Open D
77.860 70 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
16.3
75
0.0200
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
2.0
425
0.0470
3.5
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
3.3
985
0.0390
5.0
19.91
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
3.7
970
0.0160
4.4
53.12
Channel Flow,
Area= 12.0 sf Perim= 11.0' r= 1.09' n= 0.045
25.3 2,455 Total
Subcatchment 10S: TO WQ #3 POST
Runoff = 9.90 cfs @ 11.96 hrs, Volume= 0.464 af, Depth= 1.74"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
1.450 74 Onsite Open Space HSG 'C'
1.750 98 Onsite Impervious
3.200 87 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 11S: TO WQ #4
Runoff = 6.86 cfs @ 11.96 hrs, Volume= 0.317 af, Depth= 1.38"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
0.970 98 Impervious
1.790 74 >75% Grass cover, Good, HSG C
2.760 82 Weighted Average

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 8
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Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 15S: TO DP #4
Runoff = 10.83 cfs @ 12.12 hrs, Volume= 0.833 af, Depth= 0.76"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 1 -Year Rainfall= 3.00"
Area (ac) CN Description
3.470 55 Onsite Woods B
9.680 77 Onsite Woods D
13.150 71 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
0.0
14.5
75
0.0270
0.1
0.7
Sheet Flow,
1,663
0.43
3.00
40.5
21.0
Woods: Light underbrush n= 0.400 P2= 3.50"
1.0
268
0.0820
4.6
691,125
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
0.4
163
0.0740
6.9
27.42
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
1.3
663
0.0410
8.2
123.34
Channel Flow,
Area= 15.0 sf Perim= 11.0' r= 1.36' n= 0.045
17.2 1,169 Total
Reach 4R: DP #4,5, &6 REACH
Inflow Area = 186.410 ac, Inflow Depth > 0.74" for 1 -Year event
Inflow = 106.91 cfs @ 12.23 hrs, Volume= 11.517 of
Outflow = 89.45 cfs @ 12.51 hrs, Volume= 11.476 af, Atten= 16 %, Lag= 16.8 min
Routing by Stor- Ind +Trans method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Max. Velocity= 4.5 fps, Min. Travel Time= 8.8 min
Avg. Velocity = 2.8 fps, Avg. Travel Time= 14.2 min
Peak Depth= 1.50'@ 12.36 hrs
Capacity at bank full= 1,201.80 cfs
Inlet Invert= 366.00', Outlet Invert= 347.00'
Custom cross - section table, n= 0.045
Length= 2,375.0' Slope= 0.00807'
Depth
End Area
Perim.
Storage
Discharge
(feet)
(sq -ft)
(feet)
(cubic -feet)
(cfs)
0.00
0.0
0.0
0
0.00
0.10
0.7
7.5
1,663
0.43
3.00
40.5
21.0
96,188
185.34
6.00
291.0
176.0
691,125
1,201.80

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 9
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Pond 1 PA: WQ #1
Inflow Area =
25.900 ac,
Inflow Depth = 1.07"
for 1 -Year event
Inflow =
49.69 cfs @
11.96 hrs, Volume=
2.312 of
Outflow =
1.54 cfs @
14.95 hrs, Volume=
1.140 af, Atten= 97 %, Lag= 179.1 min
Primary =
1.54 cfs @
14.95 hrs, Volume=
1.140 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 360.12' @ 14.95 hrs Surf.Area= 31,744 sf Storage= 60,484 cf
Plug -Flow detention time= 355.5 min calculated for 1.138 of (49% of inflow)
Center -of -Mass det. time= 221.4 min ( 1,073.2 - 851.8 )
Volume Invert
#1 358.00'
Mv01
e Description
267,675 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
358.00
22,700
0 0
358.50
27,300
12,500 12,500
360.00
31,600
44,175 56,675
362.00
34,000
65,600 122,275
364.00
36,300
70,300 192,575
366.00
38,800
75,100 267,675
Device Routing
Invert
Outlet Devices
#1 Primary
354.50'
36.0" x 80.0' long Culvert RCP, groove end w /headwall, Ke= 0.200
Outlet Invert= 353.70' S= 0.01007' Cc= 0.900 n= 0.013
#2 Device 1
358.00'
3.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3 Device 1
359.60'
15.0" Vert. Orifice /Grate C= 0.600
#4 Device 1
362.30'
48.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#5 Primary
363.00'
52.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max =1.53 cfs @ 14.95 hrs HW= 360.12' (Free Discharge)
= Culvert (Passes 1.53 cfs of 78.61 cfs potential flow)
2= Orifice /Grate (Orifice Controls 0.34 cfs @ 7.0 fps)
3= Orifice /Grate (Orifice Controls 1.19 cfs @ 2.5 fps)
4= Orifice /Grate ( Controls 0.00 cfs)
= Broad - Crested Rectangular Weir( Controls 0.00 cfs)
Pond 2PA: WQ #2
Inflow Area =
52.790 ac,
Inflow Depth = 1.45"
for 1 -Year event
Inflow =
137.50 cfs @
11.96 hrs, Volume=
6.364 of
Outflow =
5.37 cfs @
13.67 hrs, Volume=
3.605 af, Atten= 96 %, Lag= 102.6 min
Primary =
5.37 cfs @
13.67 hrs, Volume=
3.605 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 373.22' @ 13.67 hrs Surf.Area= 76,933 sf Storage= 161,783 cf
Plug -Flow detention time= 322.4 min calculated for 3.605 of (57% of inflow)
Center -of -Mass det. time= 203.0 min ( 1,034.9 - 831.9 )

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 10
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Volume Invert
Avail.Storage Storage Description
#1 371.00'
711,664 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
371.00
64,559
0 0
371.50
71,505
34,016 34,016
373.00
76,669
111,131 145,147
380.00
85,193
566,517 711,664
Device Routing
Invert
Outlet Devices
#1 Primary
367.00'
36.0" x 92.0' long Culvert RCP, square edge headwall, Ke= 0.500
8,249
14,646
Outlet Invert= 366.00' S= 0.01097' Cc= 0.900 n= 0.013
#2 Device 1
371.00'
4.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3 Device 1
372.40'
2.00'W x 2.00' H Vert. Orifice /Grate C= 0.600
#4 Device 1
375.30'
60.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#5 Primary
376.10'
60.0' long x 15.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max =5.36 cfs @ 13.67 hrs HW= 373.22' (Free Discharge)
1= Culvert (Passes 5.36 cfs of 73.92 cfs potential flow)
�2= Orifice /Grate (Orifice Controls 0.63 cfs @ 7.2 fps)
3= Orifice /Grate (Orifice Controls 4.74 cfs @ 2.9 fps)
4=Orifice/G rate ( Controls 0.00 cfs)
= Broad - Crested Rectangular Weir( Controls 0.00 cfs)
Pond 3P: WQ #3
Inflow Area =
3.200 ac,
Inflow Depth = 1.74"
for 1 -Year event
Inflow =
9.90 cfs @
11.96 hrs, Volume=
0.464 of
Outflow =
0.22 cfs @
15.50 hrs, Volume=
0.214 af, Atten= 98 %, Lag= 212.9 min
Primary =
0.22 cfs @
15.50 hrs, Volume=
0.214 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 405.09' @ 15.50 hrs Surf.Area= 5,596 sf Storage= 13,241 cf
Plug -Flow detention time= 378.2 min calculated for 0.214 of (46% of inflow)
Center -of -Mass det. time= 259.5 min ( 1,077.1 - 817.6 )
Volume
Invert Avail.Storage Storage
Description
#1
402.00'
51,309 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq -ft)
(cubic -feet)
(cubic -feet)
402.00
3,033
0
0
404.00
4,642
7,675
7,675
406.00
6,397
11,039
18,714
408.00
8,249
14,646
33,360
410.00
9,700
17,949
51,309

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 11
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Device
Routing
Invert
Outlet Devices
#1
Primary
402.00'
18.0" x 56.0' long Culvert RCP, square edge headwall, Ke= 0.500
6.86 cfs @
11.96 hrs, Volume=
0.317 of
Outlet Invert= 401.40' S= 0.01077' Cc= 0.900 n= 0.013
#2
Device 1
402.00'
2.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3
Device 1
405.00'
10.0" Vert. Orifice /Grate C= 0.600
Primary OutFlow Max =0.22 cfs @ 15.50 hrs HW= 405.09' (Free Discharge)
L1= Culvert (Passes 0.22 cfs of 13.01 cfs potential flow)
�2=Orifice/G rate (Orifice Controls 0.18 cfs @ 8.5 fps)
3= Orifice /Grate (Orifice Controls 0.03 cfs @ 1.0 fps)
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 381.87' @ 13.53 hrs Surf.Area= 9,999 sf Storage= 7,891 cf
Plug -Flow detention time= 312.4 min calculated for 0.179 of (56% of inflow)
Center -of -Mass det. time= 192.2 min ( 1,027.4 - 835.3 )
Volume Invert
Avail.Storage Storage Description
Pond 7P: WQ #4
Inflow Area =
2.760 ac,
Inflow Depth = 1.38"
for 1 -Year event
Inflow =
6.86 cfs @
11.96 hrs, Volume=
0.317 of
Outflow =
0.29 cfs @
13.53 hrs, Volume=
0.179 af, Atten= 96 %, Lag= 94.3 min
Primary =
0.29 cfs @
13.53 hrs, Volume=
0.179 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 381.87' @ 13.53 hrs Surf.Area= 9,999 sf Storage= 7,891 cf
Plug -Flow detention time= 312.4 min calculated for 0.179 of (56% of inflow)
Center -of -Mass det. time= 192.2 min ( 1,027.4 - 835.3 )
Volume Invert
Avail.Storage Storage Description
#1 381.00'
60,973 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
381.00
7,552
0 0
381.50
9,526
4,270 4,270
382.00
10,164
4,923 9,192
384.00
12,880
23,044 32,236
386.00
15,857
28,737 60,973
Device Routing
Invert
Outlet Devices
#1 Primary
376.00'
18.0" x 66.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 375.20' S= 0.0121 T Cc= 0.900 n= 0.013
#2 Device 1
381.00'
1.5" Vert. Orifice /Grate C= 0.600
#3 Device 1
381.60'
8.0" Vert. Orifice /Grate C= 0.600
#4 Primary
383.30'
48.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max =0.29 cfs @ 13.53 hrs HW= 381.87' (Free Discharge)
Culvert (Passes 0.29 cfs of 19.25 cfs potential flow)
2 =Orifice /Grate (Orifice Controls 0.05 cfs @ 4.3 fps)
3= Orifice /Grate (Orifice Controls 0.24 cfs @ 1.8 fps)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

1121 - POST DEVELOPMENT - DP #1 Type// 24 -hr 1 -Year Rainfall= 3.00"
Prepared by {enter your company name here} Page 12
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Link 3L: DP #1
Inflow Area = 755.420 ac, Inflow Depth > 0.80" for 1 -Year event
Inflow = 312.27 cfs @ 12.39 hrs, Volume= 50.160 of
Primary = 312.27 cfs @ 12.39 hrs, Volume= 50.160 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 6L: DP #7 POST
Inflow Area = 3.200 ac, Inflow Depth > 0.80" for 1 -Year event
Inflow = 0.22 cfs @ 15.50 hrs, Volume= 0.214 of
Primary = 0.22 cfs @ 15.50 hrs, Volume= 0.214 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 10L: DP #2
Inflow Area = 414.770 ac, Inflow Depth > 0.85" for 1 -Year event
Inflow = 206.86 cfs @ 12.31 hrs, Volume= 29.486 of
Primary = 206.86 cfs @ 12.31 hrs, Volume= 29.486 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
1 -Year Primary Outflow Imported from 1121 - POST DEVELOPMENT - DP #2-Link 10L
Link 11 L: DP #3
Inflow Area = 257.790 ac, Inflow Depth > 0.73" for 1 -Year event
Inflow = 96.12 cfs @ 12.51 hrs, Volume= 15.699 of
Primary = 96.12 cfs @ 12.51 hrs, Volume= 15.699 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 13L: DP #5
Inflow Area = 173.260 ac, Inflow Depth > 0.74" for 1 -Year event
Inflow = 99.40 cfs @ 12.24 hrs, Volume= 10.683 of
Primary = 99.40 cfs @ 12.24 hrs, Volume= 10.683 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 13
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Time span =0.00 -25.00 hrs, dt =0.05 hrs, 501 points
Runoff by SCS TR -20 method, UH =SCS
Reach routing by Stor- Ind +Trans method - Pond routing by Stor -Ind method
Subcatchment 1S: TO DP #1 RunoffArea= 56.960 ac Runoff Depth >1.12"
Flow Length= 3,173' Tc =23.6 min CN =72 Runoff =60.13 cfs 5.321 of
Subcatchment 2S: TO DP #3 Runoff Area= 18.590 ac Runoff Depth >0.62"
Flow Length =2,277' Tc =21.0 min CN =62 Runoff =9.34 cfs 0.953 of
Subcatchment 3S: TO WQ #2 Runoff Area = 52.790 ac Runoff Depth= 1.86"
Tc =5.0 min CN =83 Runoff = 175.88 cfs 8.176 of
Subcatchment 4S: TO WQ #1 Runoff Area = 25.900 ac Runoff Depth= 1.43"
Tc =5.0 min CN =77 Runoff =66.74 cfs 3.087 of
Subcatchment 7S: TO DP #5 RunoffArea= 92.640 ac Runoff Depth >1.06"
Flow Length= 3,614' Tc =29.0 min CN =71 Runoff =80.03 cfs 8.211 of
Subcatchment 8S: TO DP #6 RunoffArea= 77.860 ac Runoff Depth >1.01"
Flow Length= 2,455' Tc =25.3 min CN =70 Runoff =68.94 cfs 6.541 of
Subcatchment 10S: TO WQ #3 POST Runoff Area =3.200 ac Runoff Depth= 2.18"
Tc =5.0 min CN =87 Runoff =12.32 cfs 0.582 of
Subcatchment 11S: TO WQ #4 RunoffArea =2.760 ac Runoff Depth= 1.78"
Tc =5.0 min CN =82 Runoff =8.84 cfs 0.410 of
Subcatchment 15S: TO DP #4 Runoff Area = 13.150 ac Runoff Depth= 1.06"
Flow Length= 1,169' Tc =17.2 min CN =71 Runoff =15.85 cfs 1.166 of
Reach 4R: DP #4,5, &6 REACH Peak Depth =2.20' Max Vet =4.6 fps Inflow= 159.92 cfs 16.186 of
n =0.045 L= 2,375.0' S=0.0080'/' Capacity= 1,201.80 cfs Outflow= 133.84 cfs 16.144 of
Pond 1 PA: WQ #1 Peak EIev= 360.47' Storage= 71.752 cf Inflow =66.74 cfs 3.087 of
Outflow =3.28 cfs 1.885 of
Pond 2PA: WQ #2 Peak EIev= 373.66' Storage= 196.244 cf Inflow= 175.88 cfs 8.176 of
Outflow =9.80 cfs 5.331 of
Pond 3P: WQ #3 Peak EIev= 405.35' Storage= 14.720 cf Inflow =12.32 cfs 0.582 of
Outflow =0.62 cfs 0.319 of
Pond 7P: WQ #4 Peak EIev= 382.03' Storage =9,456 cf Inflow =8.84 cfs 0.410 of
Outflow =0.58 cfs 0.268 of
Link 3L: DP #1 Inflow= 463.04 cfs 70.206 of
Primary= 463.04 cfs 70.206 of

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 14
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Link 6L: DP #7 POST
Inflow =0.62 cfs 0.319 of
Primary=0.62 cfs 0.319 of
2 -Year Primary Outflow Imported from 1121 - POST DEVELOPMENT - DP#2 —Link 10L Inflow= 300.95 cfs 40.571 of
Primary= 300.95 cfs 40.571 of
Link 11L: DP #3
Link 13L: DP #5
Inflow= 147.25 cfs 22.429 of
Primary= 147.25 cfs 22.429 of
Inflow= 148.23 cfs 15.021 of
Primary= 148.23 cfs 15.021 of
Total Runoff Area = 343.850 ac Runoff Volume = 34.447 of Average Runoff Depth = 1.20"

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 15
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Subcatchment 1S: TO DP #1
Runoff = 60.13 cfs @ 12.19 hrs, Volume= 5.321 af, Depth> 1.12"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
9.420
55
Onsite Woods B
7.960
70
Onsite Woods C
11.290
77
Onsite Woods D
1.360
55
Offsite Woods B
0.890
70
Offsite Woods C
22.510
77
Offsite Woods D
3.530
80
Offsite Open D
56.960 72 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
12.4
75
0.0400
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.6
415
0.0720
4.3
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
4.1
1,205
0.0380
4.9
19.65
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
3.0
945
0.0060
5.3
399.05
Channel Flow,
Area= 75.0 sf Perim= 25.0' r= 3.00' n= 0.045
2.5
533
0.0020
3.6
534.69
Channel Flow,
Area= 150.0 sf Perim= 40.0' r= 3.75' n= 0.045
23.6 3,173 Total
Subcatchment 2S: TO DP #3
Runoff = 9.34 cfs @ 12.18 hrs, Volume= 0.953 af, Depth> 0.62"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
11.900 55 Onsite Woods B
4.010 70 Onsite Woods C
2.050 77 Onsite Woods D
0.630 80 Onsite Open D
18.590 62 Weighted Average

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 16
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Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
12.4
75
0.0400
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.7
374
0.0530
3.7
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
1.0
440
0.0780
7.0
28.15
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
5.9
1,388
0.0080
3.9
78.72
Channel Flow,
Area= 20.0 sf Perim= 13.0' r= 1.54' n= 0.045
21.0 2,277 Total
Subcatchment 3S: TO WQ #2
Runoff = 175.88 cfs @ 11.96 hrs, Volume= 8.176 af, Depth= 1.86"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
25.640 98 Impervious
15.030 74 >75% Grass cover, Good, HSG C
12.120 61 >75% Grass cover. Good. HSG B
52.790 83 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 4S: TO WQ #1
Runoff = 66.74 cfs @ 11.96 hrs, Volume= 3.087 af, Depth= 1.43"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
10.570 98 Impervious
14.150 61 >75% Grass cover, Good, HSG B
1.180 74 >75% Grass cover, Good, HSG C
25.900 77 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 17
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Subcatchment 7S: TO DP #5
Runoff = 80.03 cfs @ 12.26 hrs, Volume= 8.211 af, Depth> 1.06"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
9.950
55
Onsite Woods B
0.000
70
Onsite Woods C
10.600
77
Onsite Woods D
0.700
61
Onsite Open B
0.000
74
Onsite Open C
9.880
80
Onsite Open D
8.410
55
Offsite Woods B
27.310
70
Offsite Woods C
7.570
77
Offsite Woods D
0.330
61
Offsite Open B
10.370
74
Offsite Open C
7.520
80
Offsite Open D
92.640
71
Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
16.3
75
0.0200
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.7
354
0.0450
3.4
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
2.0
600
0.0400
5.0
20.16
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
1.2
341
0.0260
4.8
28.83
Channel Flow,
Area= 6.0 sf Perim= 7.0' r= 0.86' n= 0.045
4.3
1,310
0.0210
5.1
60.85
Channel Flow,
Area= 12.0 sf Perim= 11.0' r= 1.09' n= 0.045
3.5
934
0.0100
4.4
88.02
Channel Flow,
Area= 20.0 sf Perim= 13.0' r= 1.54' n= 0.045
29.0 3,614 Total
Subcatchment 8S: TO DP #6
Runoff = 68.94 cfs @ 12.21 hrs, Volume= 6.541 af, Depth> 1.01"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type 11 24 -hr 2 -Year Rainfall= 3.50"

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 18
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Area (ac)
CN
Description
4.370
55
Onsite Woods D
1.550
70
Onsite Woods C
12.050
55
Offsite Woods B
24.250
70
Offsite Woods C
27.090
77
Offsite Woods D
1.000
61
Offsite Open B
2.520
74
Offsite Open C
5.030
80
Offsite Open D
77.860 70 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
16.3
75
0.0200
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
2.0
425
0.0470
3.5
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
3.3
985
0.0390
5.0
19.91
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
3.7
970
0.0160
4.4
53.12
Channel Flow,
Area= 12.0 sf Perim= 11.0' r= 1.09' n= 0.045
25.3 2,455 Total
Subcatchment 10S: TO WQ #3 POST
Runoff = 12.32 cfs @ 11.96 hrs, Volume= 0.582 af, Depth= 2.18"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
1.450 74 Onsite Open Space HSG 'C'
1.750 98 Onsite Impervious
3.200 87 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 11S: TO WQ #4
Runoff = 8.84 cfs @ 11.96 hrs, Volume= 0.410 af, Depth= 1.78"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
0.970 98 Impervious
1.790 74 >75% Grass cover, Good, HSG C
2.760 82 Weighted Average

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 19
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 15S: TO DP #4
Runoff = 15.85 cfs @ 12.11 hrs, Volume= 1.166 af, Depth= 1.06"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 2 -Year Rainfall= 3.50"
Area (ac) CN Description
3.470 55 Onsite Woods B
9.680 77 Onsite Woods D
13.150 71 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
0.0
14.5
75
0.0270
0.1
0.7
Sheet Flow,
1,663
0.43
3.00
40.5
21.0
Woods: Light underbrush n= 0.400 P2= 3.50"
1.0
268
0.0820
4.6
691,125
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
0.4
163
0.0740
6.9
27.42
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
1.3
663
0.0410
8.2
123.34
Channel Flow,
Area= 15.0 sf Perim= 11.0' r= 1.36' n= 0.045
17.2 1,169 Total
Reach 4R: DP #4,5, &6 REACH
Inflow Area = 186.410 ac, Inflow Depth > 1.04" for 2 -Year event
Inflow = 159.92 cfs @ 12.22 hrs, Volume= 16.186 of
Outflow = 133.84 cfs @ 12.50 hrs, Volume= 16.144 af, Atten= 16 %, Lag= 16.6 min
Routing by Stor- Ind +Trans method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Max. Velocity= 4.6 fps, Min. Travel Time= 8.7 min
Avg. Velocity = 2.9 fps, Avg. Travel Time= 13.6 min
Peak Depth= 2.20'@ 12.35 hrs
Capacity at bank full= 1,201.80 cfs
Inlet Invert= 366.00', Outlet Invert= 347.00'
Custom cross - section table, n= 0.045
Length= 2,375.0' Slope= 0.00807'
Depth
End Area
Perim.
Storage
Discharge
(feet)
(sq -ft)
(feet)
(cubic -feet)
(cfs)
0.00
0.0
0.0
0
0.00
0.10
0.7
7.5
1,663
0.43
3.00
40.5
21.0
96,188
185.34
6.00
291.0
176.0
691,125
1,201.80

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 20
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 360.47' @ 13.32 hrs Surf.Area= 32,167 sf Storage= 71,752 cf
Plug -Flow detention time= 292.3 min calculated for 1.885 of (61 % of inflow)
Center -of -Mass det. time= 171.2 min ( 1,014.4 - 843.2 )
Volume Invert
#1 358.00'
Mv01
e Description
267,675 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Pond 1 PA: WQ #1
Inflow Area =
25.900 ac,
Inflow Depth = 1.43"
for 2 -Year event
Inflow =
66.74 cfs @
11.96 hrs, Volume=
3.087 of
Outflow =
3.28 cfs @
13.32 hrs, Volume=
1.885 af, Atten= 95 %, Lag= 81.5 min
Primary =
3.28 cfs @
13.32 hrs, Volume=
1.885 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 360.47' @ 13.32 hrs Surf.Area= 32,167 sf Storage= 71,752 cf
Plug -Flow detention time= 292.3 min calculated for 1.885 of (61 % of inflow)
Center -of -Mass det. time= 171.2 min ( 1,014.4 - 843.2 )
Volume Invert
#1 358.00'
Mv01
e Description
267,675 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
358.00
22,700
0 0
358.50
27,300
12,500 12,500
360.00
31,600
44,175 56,675
362.00
34,000
65,600 122,275
364.00
36,300
70,300 192,575
366.00
38,800
75,100 267,675
Device Routing
Invert
Outlet Devices
#1 Primary
354.50'
36.0" x 80.0' long Culvert RCP, groove end w /headwall, Ke= 0.200
Outlet Invert= 353.70' S= 0.01007' Cc= 0.900 n= 0.013
#2 Device 1
358.00'
3.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3 Device 1
359.60'
15.0" Vert. Orifice /Grate C= 0.600
#4 Device 1
362.30'
48.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#5 Primary
363.00'
52.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max =3.28 cfs @ 13.32 hrs HW= 360.47' (Free Discharge)
= Culvert (Passes 3.28 cfs of 82.57 cfs potential flow)
2= Orifice /Grate (Orifice Controls 0.37 cfs @ 7.6 fps)
3= Orifice /Grate (Orifice Controls 2.91 cfs @ 3.2 fps)
4= Orifice /Grate ( Controls 0.00 cfs)
= Broad - Crested Rectangular Weir( Controls 0.00 cfs)
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 373.66' @ 12.94 hrs Surf.Area= 77,476 sf Storage= 196,244 cf
Plug -Flow detention time= 283.9 min calculated for 5.331 of (65% of inflow)
Center -of -Mass det. time= 174.7 min ( 999.4 - 824.7 )
Pond 2PA: WQ #2
Inflow Area =
52.790 ac,
Inflow Depth = 1.86"
for 2 -Year event
Inflow =
175.88 cfs @
11.96 hrs, Volume=
8.176 of
Outflow =
9.80 cfs @
12.94 hrs, Volume=
5.331 af, Atten= 94 %, Lag= 59.2 min
Primary =
9.80 cfs @
12.94 hrs, Volume=
5.331 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 373.66' @ 12.94 hrs Surf.Area= 77,476 sf Storage= 196,244 cf
Plug -Flow detention time= 283.9 min calculated for 5.331 of (65% of inflow)
Center -of -Mass det. time= 174.7 min ( 999.4 - 824.7 )

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 21
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Volume Invert
Avail.Storage Storage Description
#1 371.00'
711,664 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
371.00
64,559
0 0
371.50
71,505
34,016 34,016
373.00
76,669
111,131 145,147
380.00
85,193
566,517 711,664
Device Routing
Invert
Outlet Devices
#1 Primary
367.00'
36.0" x 92.0' long Culvert RCP, square edge headwall, Ke= 0.500
8,249
14,646
Outlet Invert= 366.00' S= 0.01097' Cc= 0.900 n= 0.013
#2 Device 1
371.00'
4.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3 Device 1
372.40'
2.00'W x 2.00' H Vert. Orifice /Grate C= 0.600
#4 Device 1
375.30'
60.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#5 Primary
376.10'
60.0' long x 15.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max =9.80 cfs @ 12.94 hrs HW= 373.66' (Free Discharge)
1= Culvert (Passes 9.80 cfs of 77.33 cfs potential flow)
�2= Orifice /Grate (Orifice Controls 0.69 cfs @ 7.9 fps)
3= Orifice /Grate (Orifice Controls 9.11 cfs @ 3.6 fps)
4=Orifice/G rate ( Controls 0.00 cfs)
= Broad - Crested Rectangular Weir( Controls 0.00 cfs)
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 405.35' @ 13.00 hrs Surf.Area= 5,823 sf Storage= 14,720 cf
Plug -Flow detention time= 304.1 min calculated for 0.319 of (55% of inflow)
Center -of -Mass det. time= 191.6 min ( 1,002.8 - 811.1 )
Volume
Invert Avail.Storage Storage
Pond 3P: WQ #3
Inflow Area =
3.200 ac,
Inflow Depth = 2.18"
for 2 -Year event
Inflow =
12.32 cfs @
11.96 hrs, Volume=
0.582 of
Outflow =
0.62 cfs @
13.00 hrs, Volume=
0.319 af, Atten= 95 %, Lag= 63.0 min
Primary =
0.62 cfs @
13.00 hrs, Volume=
0.319 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 405.35' @ 13.00 hrs Surf.Area= 5,823 sf Storage= 14,720 cf
Plug -Flow detention time= 304.1 min calculated for 0.319 of (55% of inflow)
Center -of -Mass det. time= 191.6 min ( 1,002.8 - 811.1 )
Volume
Invert Avail.Storage Storage
Description
#1
402.00'
51,309 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq -ft)
(cubic -feet)
(cubic -feet)
402.00
3,033
0
0
404.00
4,642
7,675
7,675
406.00
6,397
11,039
18,714
408.00
8,249
14,646
33,360
410.00
9,700
17,949
51,309

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 22
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Device
Routing
Invert
Outlet Devices
#1
Primary
402.00'
18.0" x 56.0' long Culvert RCP, square edge headwall, Ke= 0.500
8.84 cfs @
11.96 hrs, Volume=
0.410 of
Outlet Invert= 401.40' S= 0.01077' Cc= 0.900 n= 0.013
#2
Device 1
402.00'
2.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3
Device 1
405.00'
10.0" Vert. Orifice /Grate C= 0.600
Primary OutFlow Max =0.62 cfs @ 13.00 hrs HW= 405.35' (Free Discharge)
L1= Culvert (Passes 0.62 cfs of 13.71 cfs potential flow)
�2=Orifice/G rate (Orifice Controls 0.19 cfs @ 8.8 fps)
3= Orifice /Grate (Orifice Controls 0.43 cfs @ 2.0 fps)
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 382.03' @ 12.72 hrs Surf.Area= 10,199 sf Storage= 9,456 cf
Plug -Flow detention time= 264.9 min calculated for 0.268 of (65% of inflow)
Center -of -Mass det. time= 155.7 min ( 983.6 - 827.9 )
Volume Invert
Avail.Storage Storage Description
Pond 7P: WQ #4
Inflow Area =
2.760 ac,
Inflow Depth = 1.78"
for 2 -Year event
Inflow =
8.84 cfs @
11.96 hrs, Volume=
0.410 of
Outflow =
0.58 cfs @
12.72 hrs, Volume=
0.268 af, Atten= 93 %, Lag= 45.4 min
Primary =
0.58 cfs @
12.72 hrs, Volume=
0.268 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 382.03' @ 12.72 hrs Surf.Area= 10,199 sf Storage= 9,456 cf
Plug -Flow detention time= 264.9 min calculated for 0.268 of (65% of inflow)
Center -of -Mass det. time= 155.7 min ( 983.6 - 827.9 )
Volume Invert
Avail.Storage Storage Description
#1 381.00'
60,973 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
381.00
7,552
0 0
381.50
9,526
4,270 4,270
382.00
10,164
4,923 9,192
384.00
12,880
23,044 32,236
386.00
15,857
28,737 60,973
Device Routing
Invert
Outlet Devices
#1 Primary
376.00'
18.0" x 66.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 375.20' S= 0.0121 T Cc= 0.900 n= 0.013
#2 Device 1
381.00'
1.5" Vert. Orifice /Grate C= 0.600
#3 Device 1
381.60'
8.0" Vert. Orifice /Grate C= 0.600
#4 Primary
383.30'
48.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max =0.58 cfs @ 12.72 hrs HW= 382.03' (Free Discharge)
Culvert (Passes 0.58 cfs of 19.54 cfs potential flow)
2 =Orifice /Grate (Orifice Controls 0.06 cfs @ 4.7 fps)
3= Orifice /Grate (Orifice Controls 0.52 cfs @ 2.2 fps)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

1121 - POST DEVELOPMENT - DP #1 Type 11 24-hr 2-Year Rainfall= 3.50"
Prepared by {enter your company name here} Page 23
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Link 3L: DP #1
Inflow Area = 755.420 ac, Inflow Depth > 1.12" for 2 -Year event
Inflow = 463.04 cfs @ 12.36 hrs, Volume= 70.206 of
Primary = 463.04 cfs @ 12.36 hrs, Volume= 70.206 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 6L: DP #7 POST
Inflow Area = 3.200 ac, Inflow Depth > 1.19" for 2 -Year event
Inflow = 0.62 cfs @ 13.00 hrs, Volume= 0.319 of
Primary = 0.62 cfs @ 13.00 hrs, Volume= 0.319 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 10L: DP #2
Inflow Area = 414.770 ac, Inflow Depth > 1.17" for 2 -Year event
Inflow = 300.95 cfs @ 12.29 hrs, Volume= 40.571 of
Primary = 300.95 cfs @ 12.29 hrs, Volume= 40.571 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
2 -Year Primary Outflow Imported from 1121 - POST DEVELOPMENT - DP #2-Link 10L
Link 11 L: DP #3
Inflow Area = 257.790 ac, Inflow Depth > 1.04" for 2 -Year event
Inflow = 147.25 cfs @ 12.49 hrs, Volume= 22.429 of
Primary = 147.25 cfs @ 12.49 hrs, Volume= 22.429 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 13L: DP #5
Inflow Area = 173.260 ac, Inflow Depth > 1.04" for 2 -Year event
Inflow = 148.23 cfs @ 12.23 hrs, Volume= 15.021 of
Primary = 148.23 cfs @ 12.23 hrs, Volume= 15.021 af, Atten= 0 %,
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Lag= 0.0 min

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 24
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Time span =0.00 -25.00 hrs, dt =0.05 hrs, 501 points
Runoff by SCS TR -20 method, UH =SCS
Reach routing by Stor- Ind +Trans method - Pond routing by Stor -Ind method
Subcatchment 1S: TO DP #1 RunoffArea= 56.960 ac Runoff Depth >2.28"
Flow Length= 3,173' Tc =23.6 min CN =72 Runoff = 128.72 cfs 10.799 of
Subcatchment 2S: TO DP #3 Runoff Area= 18.590 ac Runoff Depth >1.50"
Flow Length= 2,277' Tc =21.0 min CN =62 Runoff =27.83 cfs 2.324 of
Subcatchment 3S: TO WQ #2 Runoff Area = 52.790 ac Runoff Depth= 3.26"
Tc =5.0 min CN =83 Runoff = 302.90 cfs 14.362 of
Subcatchment 4S: TO WQ #1 RunoffArea= 25.900 ac Runoff Depth= 2.71"
Tc =5.0 min CN =77 Runoff= 125.68 cfs 5.842 of
Subcatchment 7S: TO DP #5 Runoff Area = 92.640 ac Runoff Depth >2.19"
Flow Length= 3,614' Tc =29.0 min CN =71 Runoff = 176.00 cfs 16.924 of
Subcatchment 8S: TO DP #6 RunoffArea= 77.860 ac Runoff Depth >2.11"
Flow Length= 2,455' Tc =25.3 min CN =70 Runoff= 154.90 cfs 13.695 of
Subcatchment 10S: TO WQ #3 POST Runoff Area =3.200 ac Runoff Depth= 3.66"
Tc =5.0 min CN =87 Runoff =20.13 cfs 0.976 of
Subcatchment 11S: TO WQ #4 RunoffArea =2.760 ac Runoff Depth= 3.17"
Tc =5.0 min CN =82 Runoff =15.44 cfs 0.729 of
Subcatchment 15S: TO DP #4 Runoff Area = 13.150 ac Runoff Depth= 2.19"
Flow Length= 1,169' Tc =17.2 min CN =71 Runoff =34.31 cfs 2.402 of
Reach 4R: DP #4,5, &6 REACH Peak Depth =3.32' Max Vet =4.6 fps Inflow= 355.83 cfs 33.600 of
n =0.045 L= 2,375.0' S=0.0080'/' Capacity= 1,201.80 cfs Outflow= 293.20 cfs 33.553 of
Pond 1 PA: WQ #1 Peak Elev= 362.27' Storage= 131.430 cf Inflow= 125.68 cfs 5.842 of
Outflow =8.93 cfs 4.564 of
Pond 2PA: WQ #2 Peak Elev= 375.39' Storage= 331.602 cf Inflow= 302.90 cfs 14.362 of
Outflow =29.15 cfs 11.298 of
Pond 3P: WQ #3 Peak EIev= 406.45' Storage= 21.679 cf Inflow =20.13 cfs 0.976 of
Outflow =2.89 cfs 0.692 of
Pond 7P: WQ #4 Peak EIev= 382.68' Storage= 16.409 cf Inflow =15.44 cfs 0.729 of
Outflow =1.53 cfs 0.579 of
Link 3L: DP #1 Inflow= 1,052.03 cfs 143.708 of
Primary= 1,052.03 cfs 143.708 of

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 25
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Link 6L: DP #7 POST
Inflow =2.89 cfs 0.692 of
Primary=2.89 cfs 0.692 of
10 -Year Primary Outflow Imported from 1121 - POST DEVELOPMENT - DP#2 —Link 10L Inflow= 674.01 cfs 81.170 of
Primary= 674.01 cfs 81.170 of
Link 11L: DP #3
Link 13L: DP #5
I nflow= 332.56 cfs 47.175 of
Primary= 332.56 cfs 47.175 of
I nflow= 330.68 cfs 31.198 of
Primary= 330.68 cfs 31.198 of
Total Runoff Area = 343.850 ac Runoff Volume = 68.055 of Average Runoff Depth = 2.38"

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 26
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Subcatchment 1S: TO DP #1
Runoff = 128.72 cfs @ 12.17 hrs, Volume= 10.799 af, Depth> 2.28"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
9.420
55
Onsite Woods B
7.960
70
Onsite Woods C
11.290
77
Onsite Woods D
1.360
55
Offsite Woods B
0.890
70
Offsite Woods C
22.510
77
Offsite Woods D
3.530
80
Offsite Open D
56.960 72 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
12.4
75
0.0400
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.6
415
0.0720
4.3
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
4.1
1,205
0.0380
4.9
19.65
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
3.0
945
0.0060
5.3
399.05
Channel Flow,
Area= 75.0 sf Perim= 25.0' r= 3.00' n= 0.045
2.5
533
0.0020
3.6
534.69
Channel Flow,
Area= 150.0 sf Perim= 40.0' r= 3.75' n= 0.045
23.6 3,173 Total
Subcatchment 2S: TO DP #3
Runoff = 27.83 cfs @ 12.16 hrs, Volume= 2.324 af, Depth> 1.50"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
11.900 55 Onsite Woods B
4.010 70 Onsite Woods C
2.050 77 Onsite Woods D
0.630 80 Onsite Open D
18.590 62 Weighted Average

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 27
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
12.4
75
0.0400
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.7
374
0.0530
3.7
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
1.0
440
0.0780
7.0
28.15
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
5.9
1,388
0.0080
3.9
78.72
Channel Flow,
Area= 20.0 sf Perim= 13.0' r= 1.54' n= 0.045
21.0 2,277 Total
Subcatchment 3S: TO WQ #2
Runoff = 302.90 cfs @ 11.95 hrs, Volume= 14.362 af, Depth= 3.26"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
25.640 98 Impervious
15.030 74 >75% Grass cover, Good, HSG C
12.120 61 >75% Grass cover. Good. HSG B
52.790 83 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 4S: TO WQ #1
Runoff = 125.68 cfs @ 11.96 hrs, Volume= 5.842 af, Depth= 2.71"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
10.570 98 Impervious
14.150 61 >75% Grass cover, Good, HSG B
1.180 74 >75% Grass cover, Good, HSG C
25.900 77 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 28
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Subcatchment 7S: TO DP #5
Runoff = 176.00 cfs @ 12.24 hrs, Volume= 16.924 af, Depth> 2.19"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
9.950
55
Onsite Woods B
0.000
70
Onsite Woods C
10.600
77
Onsite Woods D
0.700
61
Onsite Open B
0.000
74
Onsite Open C
9.880
80
Onsite Open D
8.410
55
Offsite Woods B
27.310
70
Offsite Woods C
7.570
77
Offsite Woods D
0.330
61
Offsite Open B
10.370
74
Offsite Open C
7.520
80
Offsite Open D
92.640
71
Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
16.3
75
0.0200
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
1.7
354
0.0450
3.4
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
2.0
600
0.0400
5.0
20.16
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
1.2
341
0.0260
4.8
28.83
Channel Flow,
Area= 6.0 sf Perim= 7.0' r= 0.86' n= 0.045
4.3
1,310
0.0210
5.1
60.85
Channel Flow,
Area= 12.0 sf Perim= 11.0' r= 1.09' n= 0.045
3.5
934
0.0100
4.4
88.02
Channel Flow,
Area= 20.0 sf Perim= 13.0' r= 1.54' n= 0.045
29.0 3,614 Total
Subcatchment 8S: TO DP #6
Runoff = 154.90 cfs @ 12.20 hrs, Volume= 13.695 af, Depth> 2.11"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type 11 24 -hr 10 -Year Rainfall = 5.10"

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 29
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Area (ac)
CN
Description
4.370
55
Onsite Woods D
1.550
70
Onsite Woods C
12.050
55
Offsite Woods B
24.250
70
Offsite Woods C
27.090
77
Offsite Woods D
1.000
61
Offsite Open B
2.520
74
Offsite Open C
5.030
80
Offsite Open D
77.860 70 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
16.3
75
0.0200
0.1
Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.50"
2.0
425
0.0470
3.5
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
3.3
985
0.0390
5.0
19.91
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
3.7
970
0.0160
4.4
53.12
Channel Flow,
Area= 12.0 sf Perim= 11.0' r= 1.09' n= 0.045
25.3 2,455 Total
Subcatchment 10S: TO WQ #3 POST
Runoff = 20.13 cfs @ 11.95 hrs, Volume= 0.976 af, Depth= 3.66"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
1.450 74 Onsite Open Space HSG 'C'
1.750 98 Onsite Impervious
3.200 87 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 11S: TO WQ #4
Runoff = 15.44 cfs @ 11.96 hrs, Volume= 0.729 af, Depth= 3.17"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
0.970 98 Impervious
1.790 74 >75% Grass cover, Good, HSG C
2.760 82 Weighted Average

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 30
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Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 15S: TO DP #4
Runoff = 34.31 cfs @ 12.10 hrs, Volume= 2.402 af, Depth= 2.19"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 10 -Year Rainfall = 5.10"
Area (ac) CN Description
3.470 55 Onsite Woods B
9.680 77 Onsite Woods D
13.150 71 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft /sec)
(cfs)
0.0
14.5
75
0.0270
0.1
0.7
Sheet Flow,
1,663
0.43
3.00
40.5
21.0
Woods: Light underbrush n= 0.400 P2= 3.50"
1.0
268
0.0820
4.6
691,125
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
0.4
163
0.0740
6.9
27.42
Channel Flow,
Area= 4.0 sf Perim= 6.0' r= 0.67' n= 0.045
1.3
663
0.0410
8.2
123.34
Channel Flow,
Area= 15.0 sf Perim= 11.0' r= 1.36' n= 0.045
17.2 1,169 Total
Reach 4R: DP #4,5, &6 REACH
Inflow Area = 186.410 ac, Inflow Depth > 2.16" for 10 -Year event
Inflow = 355.83 cfs @ 12.21 hrs, Volume= 33.600 of
Outflow = 293.20 cfs @ 12.49 hrs, Volume= 33.553 af, Atten= 18 %, Lag= 16.7 min
Routing by Stor- Ind +Trans method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Max. Velocity= 4.6 fps, Min. Travel Time= 8.7 min
Avg. Velocity = 3.1 fps, Avg. Travel Time= 12.6 min
Peak Depth= 3.32'@ 12.34 hrs
Capacity at bank full= 1,201.80 cfs
Inlet Invert= 366.00', Outlet Invert= 347.00'
Custom cross - section table, n= 0.045
Length= 2,375.0' Slope= 0.00807'
Depth
End Area
Perim.
Storage
Discharge
(feet)
(sq -ft)
(feet)
(cubic -feet)
(cfs)
0.00
0.0
0.0
0
0.00
0.10
0.7
7.5
1,663
0.43
3.00
40.5
21.0
96,188
185.34
6.00
291.0
176.0
691,125
1,201.80

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 31
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Pond 1 PA: WQ #1
Inflow Area =
25.900 ac,
Inflow Depth = 2.71"
for 10 -Year event
Inflow =
125.68 cfs @
11.96 hrs, Volume=
5.842 of
Outflow =
8.93 cfs @
12.60 hrs, Volume=
4.564 af, Atten= 93 %, Lag= 38.6 min
Primary =
8.93 cfs @
12.60 hrs, Volume=
4.564 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 362.27' @ 12.60 hrs Surf.Area= 34,308 sf Storage= 131,430 cf
Plug -Flow detention time= 230.6 min calculated for 4.564 of (78% of inflow)
Center -of -Mass det. time= 142.4 min ( 967.1 - 824.7 )
Volume Invert
#1 358.00'
Mv01
e Description
267,675 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
358.00
22,700
0 0
358.50
27,300
12,500 12,500
360.00
31,600
44,175 56,675
362.00
34,000
65,600 122,275
364.00
36,300
70,300 192,575
366.00
38,800
75,100 267,675
Device Routing
Invert
Outlet Devices
#1 Primary
354.50'
36.0" x 80.0' long Culvert RCP, groove end w /headwall, Ke= 0.200
Outlet Invert= 353.70' S= 0.01007' Cc= 0.900 n= 0.013
#2 Device 1
358.00'
3.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3 Device 1
359.60'
15.0" Vert. Orifice /Grate C= 0.600
#4 Device 1
362.30'
48.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#5 Primary
363.00'
52.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max =8.93 cfs @ 12.60 hrs HW= 362.27' (Free Discharge)
= Culvert (Passes 8.93 cfs of 100.31 cfs potential flow)
2= Orifice /Grate (Orifice Controls 0.49 cfs @ 9.9 fps)
3= Orifice /Grate (Orifice Controls 8.45 cfs @ 6.9 fps)
4= Orifice /Grate ( Controls 0.00 cfs)
= Broad - Crested Rectangular Weir( Controls 0.00 cfs)
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 375.39' @ 12.41 hrs Surf.Area= 79,575 sf Storage= 331,602 cf
Plug -Flow detention time= 223.7 min calculated for 11.276 of (79% of inflow)
Center -of -Mass det. time= 139.7 min ( 948.3 - 808.6 )
Pond 2PA: WQ #2
Inflow Area =
52.790 ac,
Inflow Depth= 3.26"
for 10 -Year event
Inflow =
302.90 cfs @
11.95 hrs, Volume=
14.362 of
Outflow =
29.15 cfs @
12.41 hrs, Volume=
11.298 af, Atten= 90 %, Lag= 27.0 min
Primary =
29.15 cfs @
12.41 hrs, Volume=
11.298 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 375.39' @ 12.41 hrs Surf.Area= 79,575 sf Storage= 331,602 cf
Plug -Flow detention time= 223.7 min calculated for 11.276 of (79% of inflow)
Center -of -Mass det. time= 139.7 min ( 948.3 - 808.6 )

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 32
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Volume Invert
Avail.Storage Storage Description
#1 371.00'
711,664 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
371.00
64,559
0 0
371.50
71,505
34,016 34,016
373.00
76,669
111,131 145,147
380.00
85,193
566,517 711,664
Device Routing
Invert
Outlet Devices
#1 Primary
367.00'
36.0" x 92.0' long Culvert RCP, square edge headwall, Ke= 0.500
8,249
14,646
Outlet Invert= 366.00' S= 0.01097' Cc= 0.900 n= 0.013
#2 Device 1
371.00'
4.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3 Device 1
372.40'
2.00'W x 2.00' H Vert. Orifice /Grate C= 0.600
#4 Device 1
375.30'
60.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#5 Primary
376.10'
60.0' long x 15.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max =29.03 cfs @ 12.41 hrs HW= 375.39' (Free Discharge)
1= Culvert (Passes 29.03 cfs of 89.31 cfs potential flow)
�2= Orifice /Grate (Orifice Controls 0.88 cfs @ 10.1 fps)
3= Orifice /Grate (Orifice Controls 26.84 cfs @ 6.7 fps)
4=Orifice/G rate (Weir Controls 1.31 cfs @ 1.0 fps)
= Broad - Crested Rectangular Weir( Controls 0.00 cfs)
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 406.45' @ 12.17 hrs Surf.Area= 6,813 sf Storage= 21,679 cf
Plug -Flow detention time= 200.2 min calculated for 0.691 of (71 % of inflow)
Center -of -Mass det. time= 105.2 min ( 901.7 - 796.4 )
Volume
Invert Avail.Storage Storage
Pond 3P: WQ #3
Inflow Area =
3.200 ac,
Inflow Depth= 3.66"
for 10 -Year event
Inflow =
20.13 cfs @
11.95 hrs, Volume=
0.976 of
Outflow =
2.89 cfs @
12.17 hrs, Volume=
0.692 af, Atten= 86 %, Lag= 13.2 min
Primary =
2.89 cfs @
12.17 hrs, Volume=
0.692 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 406.45' @ 12.17 hrs Surf.Area= 6,813 sf Storage= 21,679 cf
Plug -Flow detention time= 200.2 min calculated for 0.691 of (71 % of inflow)
Center -of -Mass det. time= 105.2 min ( 901.7 - 796.4 )
Volume
Invert Avail.Storage Storage
Description
#1
402.00'
51,309 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq -ft)
(cubic -feet)
(cubic -feet)
402.00
3,033
0
0
404.00
4,642
7,675
7,675
406.00
6,397
11,039
18,714
408.00
8,249
14,646
33,360
410.00
9,700
17,949
51,309

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 33
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Device
Routing
Invert
Outlet Devices
#1
Primary
402.00'
18.0" x 56.0' long Culvert RCP, square edge headwall, Ke= 0.500
15.44 cfs @
11.96 hrs, Volume=
0.729 of
Outlet Invert= 401.40' S= 0.01077' Cc= 0.900 n= 0.013
#2
Device 1
402.00'
2.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#3
Device 1
405.00'
10.0" Vert. Orifice /Grate C= 0.600
Primary OutFlow Max =2.89 cfs @ 12.17 hrs HW= 406.45' (Free Discharge)
't--1 =Culvert (Passes 2.89 cfs of 16.36 cfs potential flow)
�2=Orifice/G rate (Orifice Controls 0.22 cfs @ 10.2 fps)
3= Orifice /Grate (Orifice Controls 2.66 cfs @ 4.9 fps)
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 382.68' @ 12.39 hrs Surf.Area= 11,086 sf Storage= 16,409 cf
Plug -Flow detention time= 205.9 min calculated for 0.578 of (79% of inflow)
Center -of -Mass det. time= 123.3 min ( 934.7 - 811.5 )
Volume Invert
Avail.Storage Storage Description
Pond 7P: WQ #4
Inflow Area =
2.760 ac,
Inflow Depth= 3.17"
for 10 -Year event
Inflow =
15.44 cfs @
11.96 hrs, Volume=
0.729 of
Outflow =
1.53 cfs @
12.39 hrs, Volume=
0.579 af, Atten= 90 %, Lag= 26.3 min
Primary =
1.53 cfs @
12.39 hrs, Volume=
0.579 of
Routing by Stor -Ind method, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Peak Elev= 382.68' @ 12.39 hrs Surf.Area= 11,086 sf Storage= 16,409 cf
Plug -Flow detention time= 205.9 min calculated for 0.578 of (79% of inflow)
Center -of -Mass det. time= 123.3 min ( 934.7 - 811.5 )
Volume Invert
Avail.Storage Storage Description
#1 381.00'
60,973 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
381.00
7,552
0 0
381.50
9,526
4,270 4,270
382.00
10,164
4,923 9,192
384.00
12,880
23,044 32,236
386.00
15,857
28,737 60,973
Device Routing
Invert
Outlet Devices
#1 Primary
376.00'
18.0" x 66.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 375.20' S= 0.0121 T Cc= 0.900 n= 0.013
#2 Device 1
381.00'
1.5" Vert. Orifice /Grate C= 0.600
#3 Device 1
381.60'
8.0" Vert. Orifice /Grate C= 0.600
#4 Primary
383.30'
48.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max =1.53 cfs @ 12.39 hrs HW= 382.68' (Free Discharge)
Culvert (Passes 1.53 cfs of 20.72 cfs potential flow)
2 =Orifice /Grate (Orifice Controls 0.08 cfs @ 6.1 fps)
3= Orifice /Grate (Orifice Controls 1.45 cfs @ 4.2 fps)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 10 -Year Rainfall= 5.10"
Prepared by {enter your company name here} Page 34
HydroCAD® 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Link 3L: DP #1
Inflow Area = 755.420 ac, Inflow Depth > 2.28" for 10 -Year event
Inflow = 1,052.03 cfs @ 12.34 hrs, Volume= 143.708 of
Primary = 1,052.03 cfs @ 12.34 hrs, Volume= 143.708 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 6L: DP #7 POST
Inflow Area = 3.200 ac, Inflow Depth > 2.60" for 10 -Year event
Inflow = 2.89 cfs @ 12.17 hrs, Volume= 0.692 of
Primary = 2.89 cfs @ 12.17 hrs, Volume= 0.692 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 10L: DP #2
Inflow Area = 414.770 ac, Inflow Depth > 2.35" for 10 -Year event
Inflow = 674.01 cfs @ 12.29 hrs, Volume= 81.170 of
Primary = 674.01 cfs @ 12.29 hrs, Volume= 81.170 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
10 -Year Primary Outflow Imported from 1121 - POST DEVELOPMENT - DP #2-Link 10L
Link 11 L: DP #3
Inflow Area = 257.790 ac, Inflow Depth > 2.20" for 10 -Year event
Inflow = 332.56 cfs @ 12.48 hrs, Volume= 47.175 of
Primary = 332.56 cfs @ 12.48 hrs, Volume= 47.175 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Link 13L: DP #5
Inflow Area = 173.260 ac, Inflow Depth > 2.16" for 10 -Year event
Inflow = 330.68 cfs @ 12.22 hrs, Volume= 31.198 of
Primary = 330.68 cfs @ 12.22 hrs, Volume= 31.198 af, Atten= 0 %, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs

HydroCAD 100 -Year Analysis (Clogged Orifices)

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 100 -Year Rainfall = 7.40"
Prepared by {enter your company name here} Page 2
HydroCADO 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Time span =0.00 -25.00 hrs, dt =0.05 hrs, 501 points
Runoff by SCS TR -20 method, UH =SCS
Reach routing by Stor- Ind +Trans method - Pond routing by Stor -Ind method
Subcatchment 3S: TO WQ #2 Runoff Area = 52.790 ac Runoff Depth = 5.41"
Tc =5.0 min CN =83 Runoff = 488.21 cfs 23.783 of
Subcatchment 4S: TO WQ #1 Runoff Area = 25.900 ac Runoff Depth= 4.73"
Tc =5.0 min CN =77 Runoff = 215.24 cfs 10.202 of
Subcatchment 10S: TO WQ #3 POST Runoff Area =3.200 ac Runoff Depth = 5.87"
Tc =5.0 min CN =87 Runoff =31.32 cfs 1.564 of
Subcatchment 11S: TO WQ #4 Runoff Area =2.760 ac Runoff Depth = 5.29"
Tc =5.0 min CN =82 Runoff =25.12 cfs 1.217 of
Pond 1 PA: WQ #1 Peak Elev= 363.89' Storage= 188,638 cf Inflow= 215.24 cfs 10.202 of
Outflow= 194.00 cfs 10.172 of
Pond 2PA: WQ #2 Peak Elev= 377.58' Storage= 509,439 cf Inflow= 488.21 cfs 23.783 of
Outflow= 388.65 cfs 23.629 of
Pond 3P: WQ #3 Peak EIev= 407.44' Storage= 28,855 cf Inflow =31.32 cfs 1.564 of
Outflow =29.80 cfs 1.564 of
Pond 7P: WQ #4 Peak EIev= 383.63' Storage= 27,594 cf Inflow =25.12 cfs 1.217 of
Outflow =23.37 cfs 1.217 of
Total Runoff Area = 84.650 ac Runoff Volume = 36.767 of Average Runoff Depth = 5.21"

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 100 -Year Rainfall = 7.40"
Prepared by {enter your company name here} Page 3
HydroCADO 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Subcatchment 3S: TO WQ #2
Runoff = 488.21 cfs @ 11.95 hrs, Volume= 23.783 af, Depth= 5.41"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 100 -Year Rainfall= 7.40"
Area (ac) CN Description
25.640 98 Impervious
15.030 74 >75% Grass cover, Good, HSG C
12.120 61 >75% Grass cover, Good, HSG B
52.790 83 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft /ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 4S: TO WQ #1
Runoff = 215.24 cfs @ 11.95 hrs, Volume= 10.202 af, Depth= 4.73"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 100 -Year Rainfall= 7.40"
Area (ac) CN Description
10.570 98 Impervious
14.150 61 >75% Grass cover, Good, HSG B
1.180 74 >75% Grass cover, Good, HSG C
25.900 77 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft /ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 10S: TO WQ #3 POST
Runoff = 31.32 cfs @ 11.95 hrs, Volume= 1.564 af, Depth= 5.87"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 100 -Year Rainfall= 7.40"
Area (ac) CN Description
1.450 74 Onsite Open Space HSG 'C'
1.750 98 Onsite Impervious
3.200 87 Weighted Average

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 100 -Year Rainfall = 7.40"
Prepared by {enter your company name here} Page 4
HydroCADO 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft /ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 11 S: TO WQ #4
Runoff = 25.12 cfs @ 11.95 hrs, Volume= 1.217 af, Depth= 5.29"
Runoff by SCS TR -20 method, UH =SCS, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Type II 24 -hr 100 -Year Rainfall= 7.40"
Area (ac) CN Description
0.970 98 Impervious
1.790 74 >75% Grass cover, Good, HSG C
2.760 82 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft /ft) (ft/sec) (cfs)
5.0 Direct Entry,
Pond 1 PA: WQ #1
Inflow Area = 25.900 ac, Inflow Depth= 4.73" for 100 -Year event
Inflow = 215.24 cfs @ 11.95 hrs, Volume= 10.202 of
Outflow = 194.00 cfs @ 11.99 hrs, Volume= 10.172 af, Atten= 10 %, Lag= 2.1 min
Primary = 194.00 cfs @ 11.99 hrs, Volume= 10.172 of
Routing by St - thod, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Starting Elev ' Surf.Area= 34,345 sf Storage= 132,527 cf
Peak Elev= 363.89' @ 11.99 hrs Surf.Area= 36,175 sf Storage= 188,638 cf (56,111 cf above start)
Plug -Flow detention time= 172.5 min calculated for 7.115 of (70% of inflow)
Center -of -Mass det. time= 16.5 min ( 825.3 - 808.8 )
Volume Invert
Avail.Storage Storage Description
#1 358.00'
267,675 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
358.00
22,700
0 0
358.50
27,300
12,500 12,500
360.00
31,600
44,175 56,675
362.00
34,000
65,600 122,275
364.00
36,300
70,300 192,575
366.00
38,800
75,100 267,675
Device Routing
Invert
Outlet Devices
#1 Primary
354.50'
36.0" x 80.0' long Culvert RCP, groove end w /headwall, Ke= 0.200
Outlet Invert= 353.70' S= 0.0100 T Cc= 0.900 n=0.013
#2 Device 1
358.00'
3.0" Horiz. Orifice /Grate Limited to weir flow C=0.600
#3 Device 1
359.60'
15.0" Vert. Orifice /Grate C= 0.600
NX
#4 Device 1
362.30'
48.0" Horiz. Orifice /Grate ted to weir flow C= 0.600

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 100 -Year Rainfall = 7.40"
Prepared by {enter your company name here} Page 5
HydroCADO 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
#5 Primary 363.00' 52.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max = 189.86 cfs @ 11.99 hrs HW= 363.87' (Free Discharge)
1=Culvert (Passes 75.89 cfs of 113.85 cfs potential flow)
= ri ice rate on ro s c s
3= Orifice /Grate ( Controls 0.00 cfs)
4= ri ice rate ri ice ontro s .89 cfs @ 6.0 fps)
5= Broad -Crested Rectangular Weir(Weir Controls 113.97 cfs @ 2.5 fps)
Ro09EO Stothod, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
StaSurf.Area= 79,470 sf Storage= 324,706 cf
Peak Elev= 377.58' @ 12.01 hrs Surf.Area= 82,252 sf Storage= 509,439 cf (184,733 cf above start)
Plug -Flow detention time= 185.8 min calculated for 16.175 of (68% of inflow)
Center -of -Mass det. time= 23.7 min ( 818.1 - 794.3 )
Volume Invert
Avail.Storage Storage Description
Pond 2PA: WQ #2
Inflow Area =
52.790 ac,
Inflow Depth = 5.41"
for 100 -Year event
Inflow =
488.21 cfs @
11.95 hrs, Volume=
23.783 of
Outflow =
388.65 cfs @
12.01 hrs, Volume=
23.629 af, Atten= 20 %, Lag= 3.2 min
Primary =
388.65 cfs @
12.01 hrs, Volume=
23.629 of
Ro09EO Stothod, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
StaSurf.Area= 79,470 sf Storage= 324,706 cf
Peak Elev= 377.58' @ 12.01 hrs Surf.Area= 82,252 sf Storage= 509,439 cf (184,733 cf above start)
Plug -Flow detention time= 185.8 min calculated for 16.175 of (68% of inflow)
Center -of -Mass det. time= 23.7 min ( 818.1 - 794.3 )
Volume Invert
Avail.Storage Storage Description
#1 371.00'
711,664 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
371.00
64,559
0 0
371.50
71,505
34,016 34,016
373.00
76,669
111,131 145,147
380.00
85,193
566,517 711,664
Device Routing
Invert
Outlet Devices
#1 Primary
367.00'
36.0" x 92.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 366.00' S= '/' Cc= 0.900 n=0.013
#2 Device 1
371.00'
4.0" Horiz. Orifice /Grate 0.00 Limited to weir flow C=0.600
#3 Device 1
372.40'
2.00'W x 2.00'H Vert. Orifice /Grat C= 0.600
#4 Device 1
375.30'
60.0" Horiz. Orifice /Grate Limited to weir flow C= 0.600
#5 Primary
376.10'
60.0' long x 15.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max = 383.38 cfs @ 12.01 hrs HW= 377.57' (Free Discharge)
11=-Culvert Inlet Controls 102.48 cfs 14.5 fps)
=Orifice/Grate ontrols 0.00 c s
3= Orifice /Grate Controls 0.00 cfs
4= Orifice /Grate (Passes 102.48 cfs of 142.33 cfs potential flow)
5= Broad -Crested Rectangular Weir (Weir Controls 280.90 cfs @ 3.2 fps)

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 100 -Year Rainfall = 7.40"
Prepared by {enter your company name here} Page 6
HydroCADO 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
k9flWME thod, Time Span= 0.00-25.00 hrs, dt= 0.05 hrs
Surf.Area= 7,323 sf Storage= 25,574 cf
Peak Elev= 407.44' @ 11.97 hrs Surf.Area= 7,727 sf Storage= 28,855 cf (3,281 cf above start)
Plug -Flow detention time= 185.3 min calculated for 0.977 of (62% of inflow)
Center -of -Mass det. time= 4.0 min ( 787.3 - 783.3 )
Volume Invert
Avail.Storage Storage Description
#1 402.00'
Pond 3P: WQ #3
Inflow Area =
3.200 ac,
Inflow Depth=
5.87"
for 100 -Year event
Inflow =
31.32 cfs @
11.95 hrs,
Volume=
1.564 of
Outflow =
29.80 cfs @
11.97 hrs,
Volume=
1.564 af, Atten= 5 %, Lag= 1.3 min
Primary =
29.80 cfs @
11.97 hrs,
Volume=
1.564 of
k9flWME thod, Time Span= 0.00-25.00 hrs, dt= 0.05 hrs
Surf.Area= 7,323 sf Storage= 25,574 cf
Peak Elev= 407.44' @ 11.97 hrs Surf.Area= 7,727 sf Storage= 28,855 cf (3,281 cf above start)
Plug -Flow detention time= 185.3 min calculated for 0.977 of (62% of inflow)
Center -of -Mass det. time= 4.0 min ( 787.3 - 783.3 )
Volume Invert
Avail.Storage Storage Description
#1 402.00'
51,309 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area
2.760 ac,
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
402.00
3,033
0 0
404.00
4,642
7,675 7,675
406.00
6,397
11,039 18,714
408.00
8,249
14,646 33,360
410.00
9,700
17,949 51,309
Device Routing
Invert
Outlet Devices
#1 Primary
402.00'
18.0" x 56.0' long Culver KQaQ
RCP, square edge headwall, Ke= 0.500
Outlet Invert= 401.40' S= 0.0107 T Cc= 0.900 n=0.013
#2 Device 1
402.00'
2.0" Horiz. Orifice /Grate Limited to weir flow C=0.600
#3 Device 1
405.00'
10.0" Vert. Orifice /Grate C= 0.600
#4 Primary
407.00'
40.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
T2= OutFlow Max =28.85 c 11.97 hrs HW= 407.43' (Free Discharge)
ulvert ( Controls 0.00 cfs
ri ice rate asses < .24 cfs potential flow)
3= Orifice /Grate (Passes < 3.72 cfs potential flow)
4=B road-C rested Rectangular Weir (Weir Controls 28.85 cfs @ 1.7 fps)
a sac!m thod, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Surf.Area= 11,929 sf Stora ge= 23,553 cf
Peak Elev= 383.63' @ 11.98 hrs Surf.Area= 12,381 sf Storage= 27,594 cf (4,042 cf above start)
Plug -Flow detention time= 210.0 min calculated for 0.676 of (56% of inflow)
Center -of -Mass det. time= 5.6 min ( 802.5 - 796.9 )
Pond 7P: WQ #4
Inflow Area =
2.760 ac,
Inflow Depth=
5.29"
for 100 -Year event
Inflow =
25.12 cfs @
11.95 hrs,
Volume=
1.217 of
Outflow =
23.37 cfs @
11.98 hrs,
Volume=
1.217 af, Atten= 7 %, Lag= 1.9 min
Primary =
23.37 cfs @
11.98 hrs,
Volume=
1.217 of
a sac!m thod, Time Span= 0.00 -25.00 hrs, dt= 0.05 hrs
Surf.Area= 11,929 sf Stora ge= 23,553 cf
Peak Elev= 383.63' @ 11.98 hrs Surf.Area= 12,381 sf Storage= 27,594 cf (4,042 cf above start)
Plug -Flow detention time= 210.0 min calculated for 0.676 of (56% of inflow)
Center -of -Mass det. time= 5.6 min ( 802.5 - 796.9 )

1121 - POST DEVELOPMENT - DP #1 Type 11 24 -hr 100 -Year Rainfall = 7.40"
Prepared by {enter your company name here} Page 7
HydroCADO 7.10 s/n 003899 © 2005 HydroCAD Software Solutions LLC 4/24/2012
Volume
Invert Avail.Storage Storage
Description
#1
381.00'
60,973 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq -ft)
(cubic -feet)
(cubic -feet)
381.00
7,552
0
0
381.50
9,526
4,270
4,270
382.00
10,164
4,923
9,192
384.00
12,880
23,044
32,236
386.00
15,857
28,737
60,973
Device Routinq Invert Outlet Devices
#1
Primary
376.00'
18.0" x 66.0' long Culver X 0.00
RCP, square edge headwall, Ke= 0.500
Outlet Invert= 375.20' S= 0.0121 '/' Cc= 0.900 n= 0.013
#2
Device 1
381.00'
1.5" Vert. Orifice /Grate X 0.00 C= 0.600
#3
Device 1
381.60'
8.0" Vert. Orifice /Grate X 0.00 C= 0.600
#4
Primary
383.30'
48.0' long x 10.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Pri OutFlow MaWonro 11.98 hrs HW= 383.63' (Free Discharge)
= Culvert ( Contr
= ri icl rate 0 cfs)
3= Orifice /Grate ( C ontrols 0.00 cfs)
4=B road-C rested Rectangular Weir (Weir Controls 22.57 cfs @ 1.4 fps)

Drainage Maps

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©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
HORVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.horvathassociates.com
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
.......... N
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BMP DRAINAGE MAP
SCALE: 1" 120'
0 60 120 240
SCALE: 1"= 120'
qN
3
10
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©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
HORVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.horvathassociates.com
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
BMP
DRAINAGE
MAP
NARY
E� -�NII
PR OR FOR oN
.0"s
DRAWN BY: CHECKED BY:
MLJ RH/TS
DATE
FEBRUARY 22, 2012
SCALE
1 "= 120'
PROJECT NO.
1121
SHEET NO.
BMPI
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MAP
NARY
E� -�NII
PR OR FOR oN
.0"s
DRAWN BY: CHECKED BY:
MLJ RH/TS
DATE
FEBRUARY 22, 2012
SCALE
1 "= 120'
PROJECT NO.
1121
SHEET NO.
BMPI
<CONSTRUCTION DRAWINGS>

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HOIRVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.horvathassociates.com
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
PARTIAL
GRADING &
DRAINAGE
PLAN - PHASE 1
,•,'�.� N, c�, Rai "'' -.
oFess
P- c R 'N
:.�
DRAWN BY: CHECKED BY:
FS RH/TS
DATE
APRIL 25, 2012
SCALE
AS NOTED
PROJECT NO.
1121
SHEET NO.
0401
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
<CONSTRUCTION DRAWINGS>
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PARTIAL
GRADING &
DRAINAGE
PLAN - PHASE 1
,•,'�.� N, c�, Rai "'' -.
oFess
P- c R 'N
:.�
DRAWN BY: CHECKED BY:
FS RH/TS
DATE
APRIL 25, 2012
SCALE
AS NOTED
PROJECT NO.
1121
SHEET NO.
0401
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
<CONSTRUCTION DRAWINGS>

Red trarglos at the upper fight haM correr indicate deslrgn Corr• rents
Please complete the yellow shaded iterns.
a
LEVEL SPREADER . VEGETATED FILTER STRIP (L - F ) SUPPLEMENT
This forfrr rrna f he crernplotely filled oral, prirrierf, fralfialed, ar ;cl siduidiferf,
0 L`t*7
.,anr�r'�a�
The purpose of the LS -VF
Stornevater enters LS -VFS from
Type of VFS
Explanation of any 'Other responses above
Explanation ofany'Other responses above
Explanation of any FQtheC responses above
Engineered Ater strip (graded rx sodded, slope < 8%)
Form SIN401 - LS -VFS - 27Jvi2 11 - Rev,9 page 1 of 3
srf ft
in
in
1ti
ftfcfs
29
ft
30
ft'
30
it
Form SIN401 - LS -VFS - 27Jvi2 11 - Rev,9 page 1 of 3

Elevation at clownslope base of level lip 401,00 frnsf
Elevatbn at the end of the VFS that is farthest from the LS 399.00 firr-s€
Slope (from level !;P to the end of the VFS) 6.67 %
Are any draws present in the VF S? n (Y or N) C<
Is there a collector svials at the end of the VFS? T1 (Y or N)
Bypass System Design Jif applicable)
Is a bypass system provided? n (Y or Ni
Is there an engineered flow splitting device? n (Y or N)
Dimensions of the channel (see diagram below):
Explanation of a oy 'Other responses above
IM
r,!a (Y or N)
M
IM
EDIT PIP-aso indicate the page or plan sheet nimbers where the supporting clocumenta!lon can be found, An incomplete submittal package will
result in a request for additional Information, This will delay final review and approval of the project, Initial in the space provided to indicate the
folovvilng design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a requirement has not been
met, attach justification.
Form $W401 - LS-VFS - 27,1W2011 - Rov,9 page 2 or 3

2. Plan details (1" = 30" or larger) for the level spreader showing:
- Forebay (if applicable );
High flow bypass system,
One foot tope lines between the level lip and tarp of stream bank,
Proposed drainage easement, and
Design at ultimate build -oat.
3, Secton view of the level spreader '(t" = 2V or larger) showing:
- Underdram system (if applioaUe);
Level lip;
Upsfdpe channel, and
Downstope filter fabric,
4, Plan details of the flow splitting dev oe and supporting calculations (if applicable);
5. A oonstructiott sequence that shoves how the level spreader will be protected from
sediment until Ina entire drainage area is stabilized.
6. If a non-engineered VFS is being used, then provide a photograph of the VFS showing;
that no draws are. present,
7. The supporting calculations,
8, A copy of the signed and notarized operation and maintenance (O&M) agreement;
Farm SW401 - LS -VFS - 27JuI2011 - Rev.J page 3 of 3

MATCH LINE SEE SHEET 0502
PROPERTY IDENTIFICATION NUMBERS:
A_ ♦A AA • E (AAA A•W IA AR AA AAAA
LIMITS OF
DISTURBANCE
F
3
i
�s 5 \ _
-
r .
TEMPORARY
ail
TE C50,5
I�I� .w-- DIVERSION BEf�TY1
� r s � /' \ r-- ,,,.>� rte, ."' ... (j ; % ♦ , �' ob 2
a . t
/ ✓ ✓ \8 /
-,TYP. COIR BAFFLE'--(3) 1 'SILT FENCE
Fr
Ss ,
{ / f
SEIM DETAIL �# 505 � - -- i° l � I TLET ..
{ i
C Ou
f r i `
si QITCET j t _ t r
r
_
1
i
c
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j r
ASIN #,6\ � � �•, ,~..:: � .,, � � 101" ° ~
,
I,
s~
a
cgQ� ry - -,~. 9 x185 L r t TYP. COR BAFFLE,-(3),,
FLT" (3 }:
i
< / _ C505 SEE
5.. f SEDIMENT BASIN WITH
- TAIL lC5 i `..
I
•
DIw 4 05
/ SKIMMER, 3 SPILLWAY i
t ,
F
,
I P P ELEV 2. ! G°
SKIMMER I1SCH GE I 5 -
° � _� SIN
I
! ,✓ SRUWAY ELEV 374.5
MP R RY _ f
T O f� x135' 'C
BERM ENT
� s aN � �.�.... ,, ,
_ w \
e - / \ / 2.5 SKIMtV1ER.20 sPILLYVAY
1 _ SILT FENCE { E
"`, TEMPORARY '
� �, ° - - _ I ,- � ~ -- �.. SKIMMER DISCHARGE PIPE
PROTECT( FENCE
\ 505 IUER
a C D SIGN BERM � _
_
ELEV X39.5
P. AROUND ALL WANDS AREAS ,-
' SPILLWAY ELEV = 394.5 r
p'} e -
.F }ASIN �5 i' 4 �4 .'-'' '� ./ - _-- � / d2Gtf. - _
� _ f
05'IWjx2l0`(Lj l� \ / - �, r e \
-_ i
EDiMENTI BASIN WISH _ ✓� _ c( "
4" S IM ER 4fi' S�a1LL1nl --
\ 1 Y - :..¢261 . _._..
SKIMMER DISCHARGE P[PE ELEV 55.5! BASIN #
l --
' f \ (
i - 35 _.
1 f r i SPI LWA ELEV 4 7'(Wr( 154'(1} } l _ -
8 /
- fi
f I
r 1 ! EDI EN1' BASIL ,W`ITFE .. ) "� -" '` - -�
1
1 i n
3" S 1MME 25' SPILLWAY -
(-- X
_.,...
1 -
w
,
�SE�ETAIL /CSQS KIiVIMER DISC AR 'PIPE ELEV =392.5 � :, � °'� TPBF
_
i 1 l r r 5 `�•
tPI�WAY E EV = 34.5 / i I
._TEMPORARY C 05
gyp; - � ; '� � : � � ,, ♦ � � - � 5 DIVERS( ©�EI�_ ,, - / i �- ..�° f ' l .,�' _
w -
j
t 0505 f�ASiN#
'
', ' \ \ p t t (% / f.: i r f _... 50' WJXT 0i3' ,L) _ .. ` 3 '
SIFT EE C IW 1147 BASIN . ,C "505 / BASIN4 i s /%
/ _ r / ` f` --SEDIMENT BASIN WITH
► pI1T 1=T' ° 57' W)xl14'(Lj / f% ,- ; 1 f ; (4<201 C505
;p , L1 ,AN 'S ILt AY ( ` / f � 2' PILLI�+IAY
1 [ \ p 2.5" SKIMMER -1 S ��%
a '�, A I \ EDIMENT ASTN _ i r `
rr S GVITi _ t
1
PT AL �
( l \ - - r 5ISCH ELEV =�6.5
jj %
( c; I; ♦ SILT FENCE iR> E I K1MM ' --
',:h i ti �`♦ \ " SKIMME R,14' SPILLWAY PI,('E 12 \
F ~E . -.., %,' SpItLWAY ELEV- 40$.5
I�OTECTI ENC -' / f
\ ©_ \ SKIMM DS HARD IPE ELEV =394.5
t
sj j ' f��... `f -
;.= t~. »r
� HP SPT�LWAY ELEV 39E�.5 ,'
p� F% //�
�l, C✓�J '+w- " ^.-. �`�^s,. �'-"+, x 4 _••~'T'- ...... -.r'' ,. _ 2 E ' R ©T '^
P
`� r'
€w .
eM C M F
t� 5 I ITS O
b
EN
C 05
'
l\ // 392 _ ._.-� ..�- � � (�'}fJ(j
r TPSE , 1 / q
\ ✓ter
DISTURBANCE
.. i �. I j BALL WIPE AS
M" FQ
TYP �OIR �AFI4CE 3 394 .,,., / f;- �, ' � _ M-. ! `� r . .
Iy' i C�
. � � ' ,, � o } f �. REQUIRED FOR
SEE I�ET TL`41,C"505 �. I. _ � � _ i � .� � ..� � /` � _
t', ate. F 81 '� IVERSION DITCH
�^�''" I � 4y � �'
r %
392 r DRAINAGE
39a SF f 4U6
t
398 f �Q • 1. , / I _ _ _ ... _.
V
w-
r3
SOLATED WETLANDS `
SILT FENCE.,
SILT FENC
r�
0505
_ rr
1
SEDIMENT BAST
TREE PROTECT�O / 5
C55 ISOLATED WETLANDS _
'� AM AND SPILLWAY TEMPORARY
IMITS OF DISTURBANCE FENCE >r 505 ISOLATED WETLANDS for RCP
_
(TYPICAL) DIVERSION BERM
IN -
7.1 GENERAL CONSTRUCTION SEQUENCE FOR EROSION CONTROL
INITIAL PHASE
1. INSTALL TREE PROTECTION FENCING IN ACCORDANCE WITH THE APPROVED SITE
PLAN.
2,INSPECT TREE FENCE AND SUBMIT A "TREE PROTECTION FENCING CERTIFICATION"
FORM TO DURHAM COUNTY S & E OFFICE, FAX: [phone].
3.CALL DURHAM COUNTY S &E OFFICE FOR INSPECTION OF TREE FENCE
INSTALLATION, [phone].
4.OBTAIN ALL PERMITS AND APPROVALS NECESSARY TO BEGIN AND COMPLETE THE
PROJECT. OBTAIN ALL PERMITS PRIOR TO BEGINNING ANY DISTURBANCE OF THE
SITE SO WORK WILL NOT BE INTERRUPTED.
5.SCHEDULE AND HOLD A PRE - CONSTRUCTION CONFERENCE BEFORE BEGINNING
ANY TIMBERING, CLEARING, GRUBBING, DEMOLITION OR GRADING. OWNER OR
OWNER'S REPRESENTATIVE, GRADING CONTRACTOR AND EROSION CONTROL
PERSONNEL SHALL ATTEND TO DISCUSS THE SCHEDULE AND EROSION CONTROL
PLAN.
6,CLEAR ONLY THE AREA NECESSARY TO INSTALL GRAVEL CONSTRUCTION
ENTRANCE AND SILT FENCES.
7.CLEAR THE AREA NECESSARY TO INSTALL SEDIMENT BASINS AND DIVERSION
BERMS, SEED BERMS IMMEDIATELY AFTER INSTALLATION.
8.IF A STOCKPILE IS NECESSARY DUE TO EXCAVATION OF THE SEDIMENT
TRAP /BASIN, PLACE A DOUBLE ROW OF SILT FENCE 10 FEET APART AT THE LIMITS
OF THE STOCKPILE AREA SHOWN ON THIS PLAN. TREES AND GROUNDCOVER
MAY BE REMOVED ONLY AS NECESSARY FOR THIS STOCKPILE.
9.PROVIDE TEMPORARY GROUNDCOVER FOR DIVERSION DITCHES AND SEDIMENT
TRAPS /BASINS WITHIN 3 DAYS OF COMPLETION.
INTERIM PHASE
1. BEGIN CLEARING, GRUBBING AND MASS GRADING OF SITE. INSTALL WATER
QUALITY PONDS AND RETAINING WALLS AS CONSTRUCTION SCHEDULE OF MASS
GRADING ALLOWS. MAINTAIN SLOPES TO ENSURE DRAINAGE TO SEDIMENT
BASINS /WATER QUALITY PONDS, RELOCATE DIVERSION BERMS AS REQUIRED
DURING GRADING ACTIVtTiES. AS WALL INSTALLATION BEGINS, ENSURE POSITIVE
DRAINAGE AWAY FROM AND AROUND WALLS TO DIVERSION BERMS AND
SEDIMENT BASINS.
2. CONTINUE TO GRADE SITE, INSTALLING ALL ASSOCIATED EROSION
CONTROL MEASURES. FILL OR RELOCATE SEDIMENT BASINS AS REQUIRED
DURING GRADING OPERATIONS.
1 PROVIDE ALL DISTURBED AREAS WITH GROUND COVER AS PER SEC. 1210.4(8) OF
THE DURHAM COUNTY UDO AFTER COMPLI T €ON OF ANY PHASE OF CLEARING.
E PREPARATION.
GRUBBING OR GRADING. THE SEEDING, SEEDBED MULCH
AND/OR ROLLED EROSION CONTROL PRODUCT INSTALLATION MUST BE IN
ACCORDANCE WITH THE SEEDING SCHEDULE PROVIDED IN THIS S &E PLAN,
FINAL PHASE
1. CONTINUE GRADING OF SITE, INSTALLING ROADS AND FINISHED LOT GRADES.
INSTALL UTILITIES AND STORM SEWER MAINS AND STRUCTURES, WITH ASSOCIATED
SEDIMENT CONTROL MEASURES AT STRUCTURES.
2, INSPECT AND MAINTAIN THE EROSION CONTROL DEVICES $O THEY CONTINUE TO
FUNCTION AS INTENDED, REMOVE ACCUMULATED SEDIMENT IN THE TRAPS WHEN
IT REACHES ONE -HALF THE DEPTH OF THE TRAP. REMOVE WASHED STONE ON THE
OUTLET DEVICES AND REPLACE WITH CLEAN STONE WHEN IT BECOMES
CLOGGED WITH SEDIMENT, INSPECT SILT FENCING DAILY, AND CLEAN FENCING
OF SEDIMENT AFTER EACH RAINfALL. THE PERSON RESPONSIBLE FOR EROSION
CONTROL IS ALSO RESPONSIBLE FOR INSPECTING AND MAINTAINING THESE
DEVICES,
3. IF IT IS DETERMINED DURING THE COURSE OF CONSTRUCTION THAT
SIGNIFICANT SEDIMENT IS LEAVING THE PROJECT SITE DESPITE PROPER
IMPLEMENTATION AND MAINTENANCE Of THE EROSION CONTROL PLAN,
THE PERSON RESPONSIBLE FOR THE LAND DISTURBING ACTIVITY IS
OBLIGATED TO TAKE ADDITIONAL PROTECTIVE ACTION.
4. PROVIDE ALL DISTURBED AREAS WITH GROUND COVER AS PER SEC. 12,10.4(B) OF
THE DURHAM COUNTY UDO AFTER COMPLETION OF ANY PHASE OF CLEARING,
GRUBBING OR GRADING. THE SEEDING, SEEDBED PREPARATION, MULCH
AND /OR ROLLED EROSION CONTROL PRODUCT INSTALLATION MUST BE IN
ACCORDANCE WITH THE SEEDING SCHEDULE PROVIDED IN THIS S &E PLAN,
5. REMOVE ALL TEMPORARY EROSION CONTROL DEVICES AFTER THE
DRAINAGE AREA HAS BEEN SUFFICIENTLY STABIUZED TO PREVENT EROSION.
REMOVE AND PROPERLY DISPOSE OF SEDIMENT AND DEBRIS FROM
REMAINING DEVICES AND OFF SITE DEVICES AND STABILIZE THEIR
LOCATION.
STOCKPILE AREA
1, STOCKPILE AREA TO BE ACCESSED OFF LEESVLLLE ROAD. CONTRACTOR
IS RESPONSIBLE TO MAINTAIN ALL PUBLIC ROADS IN A SEDIMENT FREE
CONDITION.
EROSION CONTROL LEGEND
DESCRIPTION
SYMBOL
DETAIL
GRAVEL CONSTRUCTION
ENTRANCE
_j
0
t
<
0U
TREE PROTECTION FENCE
LIMITS OF DISTURBANCE
-
TraF LD - TPF
C�o5
SILT FENCE
sF S> sF
3
css�s
TEMP SED. BASIN
G5ii5
TEMP. DIVERSION BERM
GsaZa
INLET PROTECTION
CL
6505
SILT FENCE OUTLET
7
csos
SKIMMER
®
&
CSS}5
INLET PROTECTION
®
�o
EROSION CONTROL PLAN -
,�INITIAL PHASE
C501 J 1" -100'
0 50 100 2€30
SCALE: I`= 100
tY
LIMITS - F i?ISTURBANC I,-
_u ARC(IED STON
r
,
,
: ,
FILT R
?`Wx12'Lx181p - APPROXIMATE .A
A5 "B' RIP
CL RA
r ! P ; LOCATION OF
f
LINE WITH FILTER FABRIC � �� � -25' AV L
GR � -.
00 '` F a r 1
� ' � 1
.434�ONSTRUCTI®
j TYP. COIR..BAFrLE (3)
r � •' / ,' SEE DETAIL 4/005 �
_
/ BASIN 9 #:
SEDIMENT BASIN-WIT I.., -.
2.5" SKIMMER, 12' SPILLWA Y
SKIT IME/R ISCHARGE PIPE ELEV_�406
SPIL I WAY ELEV M 408:5_.' !
t 0505 '
Ncl
CONSTRUCTION 1
ENTRANCE / EXIT 0505
CCOPYRIGHT 2011 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
t
HORVATH
A S S Q C I A T E S
16 CONSULTANT PLACE. SUITE 2At
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919x490.8953
537 MARKET STREET, SUITE L2)
CHATTANOOGA. TENNESSEE 37402
P 4232".4990 F 4232",5700
www,horvathassociates.eom
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EROSION
CONTROL
PLAN -
INITIAL PHASE
CA R
E S S
r • 2 •
r •
1 I PER REVIEW COMMENT I JC
04/17/2012
DRAWN BY: CHECKED Rr
FS RLH
BATE DECEMBER 19. 2011
SCALE
AS NOTED
PROJECT NO.
1126
SHEET NO.
C501
EROSION CONTROL PLAN

HORVATH
ASSOCIATES
16 CONSULTANT PAM SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919,490AWS3
537 MARKET STREET. SUITE LL20
CHATTANOOGA, TENNESSEE 37442
P 4232".4990 F 423.2".5700
www.horvathossociates,com
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EROSION
CONTROL
I ROL
PLAN -
INTERIM PHASE
slrsssslt5 air .
r•'r N CA `'•.
O �� .,..,..•,• 1 ! •.
A
i
A
�srie��it►sss'
PER REVIEW COMMENT � .3C
0411712012
DRAWN BY: CHECKED Br
FS RLH
DATE
DECEMBER 19, 2011
SCALE
AS NOTED
PROJECT NO.
1 126
SHEET' NO.
C503
EROSION CONTROL PLAN

25' R. MIN.
2�
SURGE STONE OR
R/R BALLAST
A. 2 "-3" WASHED STONE PAD TO BE 501 X 25'W. PLACE A MINIMUM OF 6" OF STONE IN A CUT SECTION TO HELP
SECURE FILTER CLOTH.
B, PROVIDE TURNING RADIUS SUFFICIENT TO ACCOMMODATE LARGE TRUCKS.
C. LOCATE ENTRANCES TO PROVIDE FOR MAXIMUM UTILITY BY ALL CONSTRUCTION VEHICLES,
D. MAINTAIN IN A CONDITION WHICH WILL PREVENT TRACKING OR DIRECT FLOW OF MUD ONTO STREETS,
PERIODIC TOP DRESSING MAY BE NECESSARY.
E. -LOCATE TEMPORARY PADS ON EACH SIDE OF ADJOINING ROADWAY �TEMPORARY l GRAVEL CONSTRUCTION ENTRANCE /EXIT
C505 J SCALE: N.T.S.
�tOia�
FABRIC
SKIMMER ­\
UNDERCUT FOR
ADDED STORAGE
IMPERMEABLE GEOTEXTILE
FABRIC
i_KUJ� Jt(_; IIUN PIPE
FRONT FACE
OVERFILL 6" FOR
SETTLEMENT
2:1 SIDE SLOPE MAX.
700 G /M' COIR
EROSION BLANKET,
COIR MESH OR
APPROVED EQUAL
SPILLWAY (LINED WITH
IMPERMEABLE
GEOTEXTILE FABRIC)
TEMP. SEDIMENT BASIN WITH SKIMMER & BAFFLES
SCALE: N.T.S.
FILTER O
STONE
END FILTER CLOTH HERE
STL. POST --�
HARDWARE CLOTH &
WIRE FENCE ONLY "
(�'7 SILT FENCE OUTLET
0505 SCALE: N.T,S.
PVC ENO
P'VC
HARDWARE CLOTH
FRONT VIEW
PLAN
FILTER CLOTH HERE
1--TOP OF SILT FENCE TO BE AT LEAST 6'
ABOVE TOP OF STONE
BURY WIRE FENCE, FILTI
FABRIC & HARDWARE
CLOTH IN TRENCH
EERSE ; —YE VIEW
PYG VENT'
r- PVC' E" PiP1 �
.wW .IV END CAP
PVC PIPE
1/.2 "SIN
I3t>k1�ICiE
WATER' SURFACE
SCHIEDULE. 40
PVC. PIK'
FRONT VIEW
PVC
MIN 4' APART
MARK SILT FENCE POST
AT j DESIGN DEPTH TO
INDICATE SILT CLEANOUT
POINT
TOE OF BERM
ILT FENCE
'C` MCLDSURE
.TER EI` TRY UNIT
SCHWA= Of SNIUM1ER TAKEN FROM PENNSYLVANIA E WS=. AND SEDIMENT POf LUiBSNi :CONIMOL MMUAL,:WACH -20M
8 SKIMMER
0505 SCALE: N.T.S.
SECTION
SCHEDULE 40
PVC F40C.
ORWICE
PLATE
36" REFLECTIVE ORANGE -^
SAFETY NETTING HOOKED
ONTO PREFORMED
CHANNELS ON METAL POST.
METAL POST @ 8'0.C.
WIRE MESH, ATTACH
WITH WIRE STAPLES
(ALTERNATE)
SIDE ELEVATION
24"X36" SIGN POSTED ON
FENCE. SEE NOTE "D" BELO
FOR LABELING METAL POST @ 8' O.C.
36" REFLECTIVE ORANGE SAFETY NETTING HOOKED
ONTO PREFORMED CHANNELS ON METAL POST.
FRONT ELEVATION
r2"
TREE PROTECTION FENCE
0505 SCALE: N.T.S.
16 GAUGE MIN. 6!'X 6" OR 4" X 4' WELDED WIRE HOOKED
ONTO PREFORMED CHANNELS ON METAL POSTS. 78' O.C. MAXI
7
ULTRAVIOLET RESISTANT GEOTEXTILE FABRIC OR `
EQUIVALENT SECURED TO WIRE WITH METAL CLIPS OR
WIRE AT WON CENTER.
TREE PROTECTION NOTES; ,MAX. SEDIMENT STORAGE LEVEL IS 1/2 HEIGHT, REMOVE S11T FENCE
SEDIMENT WHEN THIS LEVEL IS REACHED OR AS DIRECTED
A) INSTALL TREE PROTECTION FENCING AT THE SAME TIME AS THE BY THE CONSERVATION INSPECTOR. r--
EROSION CONTROL MEASURES. MAINTAIN FENCING UNTIL ALL 1 r
CONSTRUCTION IN THE VICINITY OF THE TREES IS COMPLETED. EDIMENT
STORAGE PIT FLOW
B) INSTALL TREE PROTECTION FENCING ALONG THE ENTIRE LENGTH "'-SHEET DRAINAGE ONLY.
OF THE PROPOSED CLEARING LIMITS AS DENOTED ON THE PLAN. j
FLOW
C) LOCATE TREE PROTECTION MEASURES SO THAT THEY MAINTAIN TO INCREASE STORAGE CAPACITY AND
A 6 FOOT RADIUS AROUND EXISTING PLANTS OR PROVIDE A 1 :.'.'.',•,',• PROLONG THE LIFE OF THE SILT FENCE, IT
FOOT RADIUS FOR EACH I INCH DIAMETER OF TREES (MEASURED IS GENERALLY ADVISEABLE TO DIG A
AT A POINT 4-1 FEET ABOVE GROUND), WHICHEVER IS GREATER. ' ' ' ' ....'. .'.'.'.'. NATURAL GRADE SEDIMENT PIT IN FRONT Of THE SILT
CARRY 12 INCHES OF FABRIC INTO TRENCH, FENCE WHENEVER POSSIBLE.
COVER W. SOIL, TAMP AN
D POST A SIGN ON THE FENCING STATING:'TREE PROTECTION
T? BACKFILL.
AREAMO TRESPASSING" AND "ZONA PROTECTORA PARA LOS
ARBOLES /PROHIBIDO ENTRAR ". SPACE SIGNS EVERY 75 -100 FEET.
"-- -CARRY 6" OF WIRE INTO TRENCH.
E AT THE START OF GRADING INVOLVING THE LOWERING OF THE NOTE:
° ��L FLOW SHOULD NOT RUN ALONG SILT FENCE, USE
EXISTING GRADE AROUND A TREE OR THE STRIPPING OF TOPSOIL, _ METAL POSTS AT 8' O.C. MAX. POSTS MUST DIVERSION DITCHES INSTEAD.
MAKE A CLEAN, SHARP, VERTICAL CUT AT THE EDGE OF THE TREE BE 2' DEEP MINIMUM.
SAVE AREA AT THE SAME TIME AS OTHER EROSION CONTROL NOTE:
MEASURES ARE INSTALLED, INSTALL THE TREE PROTECTION SILT FENCES SHOULD NOT BE USED AT PIPE OUTLETS OR IN AREAS OF CONCENTRATED FLOW
FENCING ON THE SIDE FARTHEST AWAY FROM THE TREE TRUNK AND (CREEKS, DITCHLINES, SWALES, ETC.).
MAINTAIN IN PLACE UNTIL ALL CONSTRUCTION IN THE VICINITY OF
THE TREES IS COMPLETE. NO STORAGE OF MATERIALS, FILL, OR
EQUIPMENT AND NO TRESPASSING SHALL BE ALLOWED WITHIN THE
PROTECTED AREA.
3 SILT FENCE
F) TREE PROTECTION FENCING MUST BE INSTALLED PRIOR TO
ISSUANCE OF ANY PERMITS. �C505JSCALE: N.T.S.
15% OF SURFACE
AREA
12" MIN
SLOPE 2:1
��0
MAX
NATURAL GROUND
RF IL L OR CU T
O
SLOPES
COMPACTED FILL
BERM
ltl
18" MIN FLO�
DITCH
18" MIN
ONE BERM /DITCH
FAB. ON
5 TEMPORARY DIVERSION BERM /DITCH
C505 SCALE: N.T.S.
A) CHISEL COMPACTED AREA AND SPREAD
TOPSOIL 3" DEEP OVER ADVERSE SOIL
CONDITIONS,
B) RIP THE ENTIRE AREA TO A 4" DEPTH.
C) REMOVE ALL LOOSE ROCK, ROOTS, AND
OTHER OBSTRUCTIONS LEAVING SURFACE
REASONABLY SMOOTH AND UNIFORM.
D) APPLY AGRICULTURAL LIME, FERTILIZER, AND
SUPERPHOSPHATE UNIFORMLY AND MIX WITH SOIL
(SEE *BELOW)
E) CONTINUE TILLAGE UNTIL A WELL PULVERIZED,
FIRM, REASONABLY UNIFORM SEED BED IS
PREPARED 5" TO 6" DEEP.
F) SEED ON A FRESHLY PREPARED SEED BED AND
COVER SEED LIGHTLY WITH SEEDING EQUIPMENT
OR CULTIPACK AFTER SEEDING.
G) MULCH IMMEDIATELY AFTER SEEDING AND
ANCHOR MULCH.
H) INSPECT ALL SEEDED AREAS AND MAKE
NECESSARY REPAIRS OR RESEEDING WITHIN THE
PLANTING SEASON, IF POSSIBLE. IF STAND
SHOULD BE OVER 60% DAMAGED, REESTABLISH
FOLLOWING ORIGINAL LIME, FERTILIZER AND
SEEDING RATES.
I) CONSULT CONSERVATION INSPECTOR ON
MAINTENANCE TREATMENT AND FERTILIZATION
AFTER PERMANENT COVER IS ESTABLISHED,
* APPLY:
AGRICULTURAL LIMESTONE: 2T /AC (3 TON IN CLAY)
FERTILIZER: 10 -10-10 AT 800- 10W#IAC
SUPERPHOSPHATE: 500# /AC OF 20% ANALYSIS
SUPERPHOSPATE
MULCH: 2 TON(80 BALES) SM. GRAIN STRAW /ACRE
ANCHOR: LIQUID ASPHALT 400 GALiAC EMULSIFIED
ASPHALT 300 GALIAC
SEEDING SCHEDULE
FOR SHOULDERS. SIDE DITCHES & SLOPES (MAX 2:1
DATE TYPE
PLANTING RATE
AUG 15 -NOV 1 CREEPING RED FESCUE
300 # /AC
NOV I -MAR I CREEPING RED FESCUE
300 # /AC
AND ABRUZZI RYE 25 # /AC
MAR I -APR 15 CREEPING RED FESCUE
300 # /AC
APR 15 -JUN 30 HULLED COMMON
BERMUDA GRASS
25 # /AC
JUL 15 -AUG 15 RED FESCUE
120 # /AC
AND BROWNTOP MILLET 35 # /RC
OR SORGHUM -SUDAN HYBRIDS 30
# /AC
FOR SLOPES 13:1 TO 2:1)
MART -JUNI CREEPING RED FESCUE
50 # /AC
(APR 15 -MAY 30) OR ADD LITTLE BLUESTEM
10/12 # /AC
(MAR I -JUNE 30) OR ADD HULLED COMMON BERMUDA
GRASS
25 # /AC
JUN 1 -SEPT I ** *CREEPING RED FESCUE AND
120 # /AC * * *BROWNTOP MILLET
35 # /AC
* * *OR SORGHUM - SULTAN HYBRIDS 30 ## /AC
SEPT I -MAR I CREEPING RED FESCUE
120 # /AC (NOV i -MAR 1)
ADD ABRUZZI RYE 25 # /AC
CONSULT CONSERVATION ENGINEER OR SCS FOR ADDITIONAL €NFORMAPON
CONCERNING OTHER ALTERNATIVES FOR VEGETATION OF DENUDED AREAS,
ABOVE VEGETATION RATES ARE THOSE WH #CH DO WEU. FINDER LOCAL
CONDITIONS: OTHER SEEDING RATE COMBINATIONS ARE POSSIBLE.
­TEMPORARY-RESEED ACCORDING TO OPTS LIM SEASON FOR DESIRED
PERMANENT VEGETATION. DO NOT ALLOW TEMPORARY COVER TO GROW
OVER 12'44 HEIGHT BEFORE MOWING, OTHERWISE FESCUE MAY BE SHADED
OUT.
A. MACHINE COMPACTION OF ALL FILL IS REQUIRED. DIVERSIONS
'r rcrjr
SUFFICIENT TO DIRECT ALL SEDIMENT - LADEN STORMWATER
A S [` O C I A T C S
INTO A SEDIMENT CONTROL DEVICE MUST BE INSTALLED PRIOR TO
CLEARING AND GRUBBING OF THE AREA (OR IN CONJUNCTION
INLET ZONE
WITH THIS OPERATION IF SEDIMENT CONTROLS AND DIVERSIONS
357o OF SURFACE
ARE INSTALLED AS EACH CRITICAL POINT IS REACHED).
AREA
■
FIRST CHAMBER
B. DIVERSIONS SHALL BE LOCATED TO MINIMIZE DAMAGES BY
25% OF SURFACE
CONSTRUCTION OPERATIONS.
AREA
SECOND CHAMBER
C. DIVERSIONS SHALL BE SEEDED AND MULCHED IF THEY ARE
25% OF SURFACE
TO REMAIN IN PLACE OVER 21 DAYS,
AREA
■
DURHAM, NORTH CAROLINA 27747
D. CHECK DEVICE AFTER EACH RAIN, BUT ONCE A WEEK REGARDLESS OF RAINFALL.
OUTLET ZONE
REPAIR AS NECESSARY.
15% OF SURFACE
AREA
12" MIN
SLOPE 2:1
��0
MAX
NATURAL GROUND
RF IL L OR CU T
O
SLOPES
COMPACTED FILL
BERM
ltl
18" MIN FLO�
DITCH
18" MIN
ONE BERM /DITCH
FAB. ON
5 TEMPORARY DIVERSION BERM /DITCH
C505 SCALE: N.T.S.
A) CHISEL COMPACTED AREA AND SPREAD
TOPSOIL 3" DEEP OVER ADVERSE SOIL
CONDITIONS,
B) RIP THE ENTIRE AREA TO A 4" DEPTH.
C) REMOVE ALL LOOSE ROCK, ROOTS, AND
OTHER OBSTRUCTIONS LEAVING SURFACE
REASONABLY SMOOTH AND UNIFORM.
D) APPLY AGRICULTURAL LIME, FERTILIZER, AND
SUPERPHOSPHATE UNIFORMLY AND MIX WITH SOIL
(SEE *BELOW)
E) CONTINUE TILLAGE UNTIL A WELL PULVERIZED,
FIRM, REASONABLY UNIFORM SEED BED IS
PREPARED 5" TO 6" DEEP.
F) SEED ON A FRESHLY PREPARED SEED BED AND
COVER SEED LIGHTLY WITH SEEDING EQUIPMENT
OR CULTIPACK AFTER SEEDING.
G) MULCH IMMEDIATELY AFTER SEEDING AND
ANCHOR MULCH.
H) INSPECT ALL SEEDED AREAS AND MAKE
NECESSARY REPAIRS OR RESEEDING WITHIN THE
PLANTING SEASON, IF POSSIBLE. IF STAND
SHOULD BE OVER 60% DAMAGED, REESTABLISH
FOLLOWING ORIGINAL LIME, FERTILIZER AND
SEEDING RATES.
I) CONSULT CONSERVATION INSPECTOR ON
MAINTENANCE TREATMENT AND FERTILIZATION
AFTER PERMANENT COVER IS ESTABLISHED,
* APPLY:
AGRICULTURAL LIMESTONE: 2T /AC (3 TON IN CLAY)
FERTILIZER: 10 -10-10 AT 800- 10W#IAC
SUPERPHOSPHATE: 500# /AC OF 20% ANALYSIS
SUPERPHOSPATE
MULCH: 2 TON(80 BALES) SM. GRAIN STRAW /ACRE
ANCHOR: LIQUID ASPHALT 400 GALiAC EMULSIFIED
ASPHALT 300 GALIAC
SEEDING SCHEDULE
FOR SHOULDERS. SIDE DITCHES & SLOPES (MAX 2:1
DATE TYPE
PLANTING RATE
AUG 15 -NOV 1 CREEPING RED FESCUE
300 # /AC
NOV I -MAR I CREEPING RED FESCUE
300 # /AC
AND ABRUZZI RYE 25 # /AC
MAR I -APR 15 CREEPING RED FESCUE
300 # /AC
APR 15 -JUN 30 HULLED COMMON
BERMUDA GRASS
25 # /AC
JUL 15 -AUG 15 RED FESCUE
120 # /AC
AND BROWNTOP MILLET 35 # /RC
OR SORGHUM -SUDAN HYBRIDS 30
# /AC
FOR SLOPES 13:1 TO 2:1)
MART -JUNI CREEPING RED FESCUE
50 # /AC
(APR 15 -MAY 30) OR ADD LITTLE BLUESTEM
10/12 # /AC
(MAR I -JUNE 30) OR ADD HULLED COMMON BERMUDA
GRASS
25 # /AC
JUN 1 -SEPT I ** *CREEPING RED FESCUE AND
120 # /AC * * *BROWNTOP MILLET
35 # /AC
* * *OR SORGHUM - SULTAN HYBRIDS 30 ## /AC
SEPT I -MAR I CREEPING RED FESCUE
120 # /AC (NOV i -MAR 1)
ADD ABRUZZI RYE 25 # /AC
CONSULT CONSERVATION ENGINEER OR SCS FOR ADDITIONAL €NFORMAPON
CONCERNING OTHER ALTERNATIVES FOR VEGETATION OF DENUDED AREAS,
ABOVE VEGETATION RATES ARE THOSE WH #CH DO WEU. FINDER LOCAL
CONDITIONS: OTHER SEEDING RATE COMBINATIONS ARE POSSIBLE.
­TEMPORARY-RESEED ACCORDING TO OPTS LIM SEASON FOR DESIRED
PERMANENT VEGETATION. DO NOT ALLOW TEMPORARY COVER TO GROW
OVER 12'44 HEIGHT BEFORE MOWING, OTHERWISE FESCUE MAY BE SHADED
OUT.
■
TOP OF DITCH
'r rcrjr
(D
A S [` O C I A T C S
Z
J
6" FREEBOARD 18" TOP
■
16 CONSULTANT PLACE, SUITE 2131
■
DURHAM, NORTH CAROLINA 27747
1
2
1
■
P 919.49€3.4944 F 919.490.8953
U
z
EXIST. DITCH
BOTTOM
■
537 MARKET STREET, SUITE L=
<
■
CHATTANOOGA, TENNESSEE 37442
423266.4490
N
a
P F 423.266.5100
www.tlaTVattlassociates.com
..;,:
■
NOTE: CUT 6" "V" NOTCH IN
CENTER OF DAM
■
■
■
■
Q
9
STONE CHECK DAM
"
^ Z
0505
SCALE. N.T.S.
■
D
■
'Q,
(D
QU
Z
J
RIP RAP HEADWALL
FLOW -_,., - ■
FILTER ,BERM
#57 WASHED STONE I' THICK X 3' ■
HIGH (MIN)
A, lam` ��� � °` � SEDIMENT STORAGE AREA ■
CURB INLET PROTECTION
PERSPECTIVE VIEW
AREAS TO BE FLOOD STORAGE RIP RAP HEADWALL (INSTALL WITH GRATE) ■
DISTURBED (CUT, ZONE 1 ri EXISTING GRADE FILLED) EXISTING INSTALLATION AND MAINTENANCE GUIDELINES
PIPE
■
I - INSTALLATION: REMOVE THE GRATE FROM CATCH
BASIN. IF USING OPTIONAL OIL ABSORBENTS; PLACE ■
F © m FLOW ABSORBENT PILLOW IN UNIT. STAND THE GRATE ON
■
END. MOVE THE TOP LIFTING STRAPS OUT OF THE WAY
CLASS I RIP RAP NOTES: AND PLACE THE GRATE INTO THE BAG SO THAT THE a
#57 WASHED STONE 1) DIMENSIONS ARE MIN. ACCEPTABLE GRATE IS BELOW THE TOP STRAPS AND ABOVE THE
SEDIMENT STORAGE ZONE UNLESS OTHERWISE NOTED. LOWER STRAPS, HOLDING THE LIFTING DEVICES, ■
MAX SEDIMENT DEPTH INLET PROTECTION INSERT THE GRATE INTO THE INLET.
(CLEAN OUT POINT) 2) USE STONE FILTER TO EXISTING PIPE INVERTS ■
THAT DRAIN 10 ACRES OR LESS ■
■
MAINTENANCE: REMOVE ALL ACCUMULATED FRM VICINITY OF UNIT
SEDIMENT AND ARCHED STONE FILTER EACH STORM EVENT. AFTER EACH STORM EVE TFTER ■
AND AT REGULAR INTERVALS, LOOK INTO THE BAG. IF ■
C505 SCALD: N.T.S. THE CONTAINMENT AREA IS MORE THAN 1/3 FULL OF
SEDIMENT, THE UNIT MUST BE EMPTIED. TO EMPTY ■
UNIT, LIFT THE UNIT OUT OF THE INLET USING THE
LIFTING STRAPS AND REMOVE THE GRATE, IF USING ■
FlUERSTONE OPTIONAL OIL ABSORBENTS; REPLACE ABSORBENT ■
DAM #5 OR #57 WHEN NEAR SATURATION.
STONE
STORAGE AREA
■
x
FLOW FLOW
• Materials used to construct temporary concrete washout
facilities shall be removed from the site of the work and
CATCH BASIN �
disposed of or recycled.
s Holes, depressions or other ground disturbance caused by the
removal of the temporary concrete washout facilities shall be ���p��p�
backfilled, repaired, and stabilized to prevent erosion. PLAN VIEW �c�3- Q� ©��p ` —GRATE �- LIFT STRAPS ■
STAPLES
(2 PER BALE)
WOOD OR METAL
STAKES (2 PER HALE)
VARIES
STRAW PALE
81ND1NG € IRE
10 mil PLASTIC LINING
NATIVE MATERIAL
(DPT1oNAt.)
NOT TO SCALE
'TAKE
TYP.)
10 r1TiI PLASTIC LINING STRAW RALi_
(IYP.)
NOT TO SCALE
TYPE "ABOVE GRADE"
WriH STRAW BALES
1. ACTUAL LAYOUT DETERMINED IN THE FIELD.
2. THE CONCRETE WASHOUT SIGN (SEE FIG. 4--15)
SHALL BE INST'ALLEO WITHIN ' 1 R m OF THE
TEMPORARY CONCRETE WASHOUT FACILITIY.
MTPAM /FW4- 14.MYti 'W 8-14-02
11 CONCRETE WASH OUT AREA
0505 SCALE: N.T.S.
EROSION
CONTROL
SITE DETAILS
CA
41,
YA GO
1 PER REVIEW COMMENT I JC
04/17/2012
DRAWN BY: CHECKED BY:
RLH
DATE
DECEMBER 19, 2011
SCALE
AS NOTED
PROJECT NO,
1126
SHES NO.
C505
ERas� ©N CQ�TRQ� ���
Uj
J
(D
Z
J
EROSION
CONTROL
SITE DETAILS
CA
41,
YA GO
1 PER REVIEW COMMENT I JC
04/17/2012
DRAWN BY: CHECKED BY:
RLH
DATE
DECEMBER 19, 2011
SCALE
AS NOTED
PROJECT NO,
1126
SHES NO.
C505
ERas� ©N CQ�TRQ� ���

Red triang!as at tKa upper rightharid comer b6cam destin commerIs
Please oomplete the yelloer shaded items,
LEVEL SPREADER - VEGETATED FILTER STRIP (LS-VFS) SUPPLEMENT
This form njust be complotshyffliadout, printed, Initiated, and subrrnttod�
Contact name
Phofie number
Date
Drainage area number
Explanation of any "Other' responses above
Explanaton of any 'Othef' responses above
Explanation of any 'Other' responses above
fe
fe
cis
min
in/hr
eta
cis
(Y or N)
Wet detention pond
8.93 cis
8.93 cis
10 cis
6,93 cis
Y (Y or N)
M
Do riot co:nplele this sestion of the f3ffr...
Do not cornplele this seollon of 9t a fora:.
Do no, oornplete W4 soclion of V a form.
Ca rict corridete rh:s section of to foun.
C. D not wrr pfe to th;s sectors a? th a .. o mn .
Do FIC-1 corrplecs ti° is scot;ou of the form.
Do riot oo ripleto this sodon of the fc -nt
Do notcornplete this sect on of the form.
Dc not compIete, thisseeJor, of file form.
Do riot confiNde this saction of tus, form.
Form SW401 - LS-VFS - 27Ju12011 • Rev 9 page 1 of 3
In
in
10
fu"fs
69
it
70
ft
30
it
Do riot co:nplele this sestion of the f3ffr...
Do not cornplele this seollon of 9t a fora:.
Do no, oornplete W4 soclion of V a form.
Ca rict corridete rh:s section of to foun.
C. D not wrr pfe to th;s sectors a? th a .. o mn .
Do FIC-1 corrplecs ti° is scot;ou of the form.
Do riot oo ripleto this sodon of the fc -nt
Do notcornplete this sect on of the form.
Dc not compIete, thisseeJor, of file form.
Do riot confiNde this saction of tus, form.
Form SW401 - LS-VFS - 27Ju12011 • Rev 9 page 1 of 3

Elevation at dowastope base of level lip
Elevation at the end of the VFS that is farthest from We LS
Slope (from level lip to the end of the VFS)
Are any draws present in the VFS?
Is there a collector svivale at this and of the VFS?
353.70
fmsl
We
ft
5.67
fill
n
or N) OK
n
—(Y
(Y or N)
y (Y or N)
y —(Y or N) Please f; rai plan doniiis of Raw splifter & supporlIg calics.
We
ft
We
ft
We
ft
We
ft
We
ft
We
It'see
Pick one:
in
(Y or N)
nis
(Y or N)
Bypm directed to plunge pool adjacent to 100-year floodplain
0
Mn rrequ rements have been rn --l. If the applicant has d asig nated an agent the agent may initial. below. If a require ment has not been
stif
stificaflorr;
Form 54IV401 - LSAIFS - 2MI2011 - Rev 9' page 2 of 3

2, Plan details (V = Wor larger) forthe level spreader shaviing,.
- Forebay (if applicable),
High flovi bypass system,
One foot topo lines between the love lip and top of stream bank,
Proposed drainage easemord, and
Design at ultimate buW-out.
3. Section view of the level spreader (V 7 Wor larger) showing:
- Underdrain system (if applicable),
- Level lip,
- Upslope channel, and
- Downslope filter fabric;
4. Plan details of the flow splitting device and supporting calculations (if applicable),
5. A construction sequence that shows how the lavelziereader will be protectedi from
sediment Wil the entire drainage area is stabilized,
6. If a non,engineered VFS is being used, then provide is pWo9raph of the VF S showing
that no draws are present.
7. The supporting calculalmns.
8. A copy of the signed and notarized operation and maintenance (OW) agreement; Ih 'Copy provided. Durham will not execute all indal pormitt =ngSee
Form SW401 - LS-VFS - 27M2011 - Rey.9 page 3 of 3

ProJect name
Contact name
Phone number
Date
Drainage area number
Stormwater enters LS-VFS from
Type of V FS
Explanation of any'Othe` responses above
Explanation of any "Other' responses above
Explanation of any'Olher" responses above
cis Do not complete this snot -on c Etie fo,(i ;
(Y or N) Do not complete this secton cline fcffm
Wet detention
pond
2915
of
29.15
'' cis
10
cts
10
cfs
y
(Y or hl)
Farm SW401 - LS -VFS - 27JW2011 - Rev ,g page 1 or 3
in
in
10
ftrcf
100'
It
100
it
30
it
Farm SW401 - LS -VFS - 27JW2011 - Rev ,g page 1 or 3

Elevation at downslope base of level lip
Elevation at the end of the VFS that is to 4ftest from the LS
Slope (from level lip to the end of the ;VFS)
Are any draws present in the VFS?
Is there a collector swale at the end of the VFS?
Bypass System Design (if applicable)
Is a bypass system proVded?
Is there an engineered flow splitting device?
Dimensions of the channel (see diagram belovi)�
36510
frIU4
364.00
fans!
5.67
%
n
(Y o* N) OK
n
(Y or NI)
y (Y or N)
y (Y or N) Please provide plan detsiis of flow splicer & sipport'rtg caics
We
it
ftfa
ft
We
ft
We
ft
n/a
ft
n1a
ftrseo
Fick one:
n
(Y or N)
n1a
(Y 0, N)
Bypass directed to plunge pool adjacent to 100-year floodplam
M
Page or plan sheet number and any notes:
(Include Rations I C coofficiient per basin),
High flow bypass aysift
•
Maintenance acceas�
IiI41411 rd full I
Form SW401 - LS-VFS - 27302011 - Rav,9 page 2 of 3

2. Plan details (I'm 30' or [a rgef) for the 10VOIS.Dreadershowiag:
- Eorebay (if applicable)
Hilih :.1tow bypass system;
One foot tape lines between the level lip and top of stream be A,
Proposed drainage easement, and
- besicdn at ultimate build- out.
. Section vier of the level spreader (V w 29 or larger) showing;
- Underdoun system (if applicable),
Level lip,
- Upskope channel, and
Downslope filter fabric;
4, Plan details of the Fmv splitting device and supporting calculations (if appli nle ),
5. A construction sequence that shows how the level spreader will be protected frorn
sediment until the entire drainage area !s stabilized,
g, If o non- engineered VFS is being used, then provide a photograph of the VFS showing
that no draws are present,
7, The supporting calculations.
Form SW40i - LS -VFS - 27JW2041 - Rov.9 page 3 of 3

III:°:PUipUWUI LIM L7-YTe3. Vnr:: tVeG. '.U' ,G{Ai tliGWGkF 11 }t4+11 99 ct rgr,IG :::.
Storrawator enters LS -VFS from k BMP
Type of VFS Engineered filter strip (graded Ik sodded, slope, 8 %)
Explanation of any *Other" responses above
Explanation of any "Other' responses above
If Stortrwater Enters the LS-VF from a BMP
Type of BMP'
Peak discharge from the BiMe'ff during the design storm
Peak discharge from the BMP during the 10- yearstorm
Maximum capacity of a 100 -foot long L -VF
Peak flow directed to the LS -VFS
Is a f'ow bypass system gofrg to be used?
I?
Do not complete this sacrinn of the flare
fe
too notcomplate this s li'm of the form.
%
fro not complete this secUen of the form
15
Do not complete this suction of the form.
CIS
Do riot complete this section of the form.
m:n
Do riot comp'e(e this section of the liver,
m1hr,
Do riot complete this soc, on rif the form
CIS
:)u riot comp'cre this sever on of Pic form,
cis Do riot comp:dte this sin; Jan of the form,
(Y or N) fro riot roe op eta flris seclion of the (tune.
Form SW4 }5 - LS -VFS - 27JIZ!2e1 t - Rev.9 page i of 3
in
to
10
Note
15
ft
!! �0
it
30
If
Form SW4 }5 - LS -VFS - 27JIZ!2e1 t - Rev.9 page i of 3

Elevation at doiynsfope base of level lip
Elevation at the end of the >VFS that is farthest from the LS
Slope (from level lip to the end of the VFS)
Are any draws present in the VFS?'
Is there a collector swale at th a end of the VF S?
375.73
frnsi
374.00
fmsl
5.67
%
n
(Y or N)
n
(Y or,N)
n (Y or N)
0 (Y or )
n (Y or N)
We {Y or N },
Bypass directed to plunge pool adjacent to 100 -year iloodplaln
W
i �
result in a request for additional information.
following design requirements have been meL If
met, attach justif!cation
on can be found, An Incomplete submittal package will
oval of the project. Initial in the SpaDe provided to indicate the
the agent may initial below. If a requirement has not been
Initials Page or plan
Form SW401 - LS -VFS - 27JuI201 i - Rev.a page 2 of 3

2. Plan details (1" = 35' or larger) for the level spreader showing;
- Forebay (if applicable),
High flow bypass sys'.em,
One foot tope lines between the level lip and top of stream bank,
Proposed drainage easement. and
Design at ultimate build out.
3, Section view of the level spreader (1" = 20' or larger) shove "ng;
- Ungerdrain system (if applicable),
Level lip,
Upslope channel, and
Dowflslope filter fabric..
5, A construction sequence Prat shows how the level spreader will be protected from
sediment until the entire drainage area is stabilized,
6, If a non- eng'Mored VFS is being; used, then provide a photograph of the VFS showing
that no d raves are present.
7. The supporting calculations;
t
Form SVV401 - LS -VFS - 27J u12011 - Rows Bags 3 of 3

■
PIN: 0769 -03 -41 -8938 PIN: 0769 -03-41 -6932 PIN: 0769 -03-41 -4887 PIN: 0769 -0442 -5588 PIN: 0769 -03 -44 -6000 PIN: 0769-03 -33 -2232 PIN: 0769-03- 248486 PIN: 0769 -03-35 -7254 PIN: 0769 -01 -35 -3524 PIN: 0769 -01 -26 -9080 PIN: 0769-01 -06 -9898 TBM SITE BENCHMARK NCGS MONUMENT ■
Parcel ID: 194413 Parcel ID: 194412 Parcel ID: 194411 Parcel ID: 194383 Parcel ID: 194384 Parcel ID: 193264 Parcel ID: 193265 Parcel ID: 210697 Parcel ID: 193271 Parcel ID: 193270 Parcel ID: 193320
I NC F EL = 409.94' NGVD 29 ■
X/7
......AY ..................
f,r` YJ
f
f
ff
f
r
1 0
J.,
v a..nv Yrvv
,1
...................
f
1
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' I x 7 utlnC
30' WIDE ENGINEERED - -- 12 ".. ..
VELOCIT
FILTER STRIP m Y DISSIi' ATOIR
v `� INSTALL FILTER..Fa4BRIC $ETtiNEEN SOIL AND R'IPI2AI
.............
AIRIA LE WIDTH BMP
S- F�SEIaAEPdT- �- T1fP�,
t r
t:.,. .. ... ... ..........
WATER QUALITY POND #1 PLAN VIEW
C4 OO SCALE: 1 " =20'
0 10 20 40
SCALE: 1 "= 20'
12'WIDE BERM
HAND WHEEL TOP OF BERM = 366.00
1OD-YEARWSE=363.89 15"0 ORIFICE
v 25-YEAR WSE 3,62-97 1.34
INV 359.60
ELEVATION 362-30
INVERTED SIPHON C 51
WITH WO ORIFICE 4.00' $
NORMAL POOL 35&00
UVA
„F red. , � — . 1.00% _
Lt
81 P L El
DEEP
POOL BOTrOM 352.00
41 EN�
MA­N­H��E�SEJRRF:j �=�K%
D D
, \WATER QUALITY POND #1 PROFILE VIEW
ca501 SCALE: N.Ts.
I�PA—GE�D��HRA­GM�
r t
710 LF ' 15 0RCP
■
■
■
■
■
• ° ��N•Ecs'RO� �''•L
V oil
■ � �'yG I NEED %P��� i
■ '•�...n.....•.
■
■
■
■
LEVEL SPREADER LIP
INVERT = 354.00 ■
HEADWALL ■
INVERT = 353.50 FILTER STRIP JUST DOWNSTREAM OF LEVEL SPREADER LIP
ELEVATION = 353.71 ■
END OF ENGINEERED FILTER STIP
10 WIDE_ ELEVATION = 352.00 ■
LINEAR WETLAND
— � i.�
:�`E�G�N�I= RED�ILV�Ef� STRIP- ■
— ■ DRAWN BY; CHECKED BY:
MU
R D R D R R ■ DATE
■ APR125, 2012
■ SCALE AS NOTED
CITY OF DURHAM ■ PROJECT NO.
t
PUBLIC WORKS DEPARTMENT
APPROVED ■ SHEET NO.
ENGINEERING DATE
■
STORM WATER DATE C450
TRANSPORTATION DATE ■
DATE ■
DATE ■ <CONSTRUCTION DRAWINGS>
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
.............. ..
J`
{
L,
-:a ri
t t
ii t
t l
l
1_.........—
5a
c
�
' I x 7 utlnC
30' WIDE ENGINEERED - -- 12 ".. ..
VELOCIT
FILTER STRIP m Y DISSIi' ATOIR
v `� INSTALL FILTER..Fa4BRIC $ETtiNEEN SOIL AND R'IPI2AI
.............
AIRIA LE WIDTH BMP
S- F�SEIaAEPdT- �- T1fP�,
t r
t:.,. .. ... ... ..........
WATER QUALITY POND #1 PLAN VIEW
C4 OO SCALE: 1 " =20'
0 10 20 40
SCALE: 1 "= 20'
12'WIDE BERM
HAND WHEEL TOP OF BERM = 366.00
1OD-YEARWSE=363.89 15"0 ORIFICE
v 25-YEAR WSE 3,62-97 1.34
INV 359.60
ELEVATION 362-30
INVERTED SIPHON C 51
WITH WO ORIFICE 4.00' $
NORMAL POOL 35&00
UVA
„F red. , � — . 1.00% _
Lt
81 P L El
DEEP
POOL BOTrOM 352.00
41 EN�
MA­N­H��E�SEJRRF:j �=�K%
D D
, \WATER QUALITY POND #1 PROFILE VIEW
ca501 SCALE: N.Ts.
I�PA—GE�D��HRA­GM�
r t
710 LF ' 15 0RCP
■
■
■
■
■
• ° ��N•Ecs'RO� �''•L
V oil
■ � �'yG I NEED %P��� i
■ '•�...n.....•.
■
■
■
■
LEVEL SPREADER LIP
INVERT = 354.00 ■
HEADWALL ■
INVERT = 353.50 FILTER STRIP JUST DOWNSTREAM OF LEVEL SPREADER LIP
ELEVATION = 353.71 ■
END OF ENGINEERED FILTER STIP
10 WIDE_ ELEVATION = 352.00 ■
LINEAR WETLAND
— � i.�
:�`E�G�N�I= RED�ILV�Ef� STRIP- ■
— ■ DRAWN BY; CHECKED BY:
MU
R D R D R R ■ DATE
■ APR125, 2012
■ SCALE AS NOTED
CITY OF DURHAM ■ PROJECT NO.
t
PUBLIC WORKS DEPARTMENT
APPROVED ■ SHEET NO.
ENGINEERING DATE
■
STORM WATER DATE C450
TRANSPORTATION DATE ■
DATE ■
DATE ■ <CONSTRUCTION DRAWINGS>
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED

4 "0 PVC CLEANOUT
WITH REMOVABLE CAP
TOP OF SIPHON ASSEMBLY = 360.00
4"o PVC
4" X4 "X4" PVC TEE
4 "0 PVC
PVC SLIP CAP WITH 3.0 "0
ORIFICE CEMENTED ONTO
END OF 4 "0 PVC SECTION
BOTTOM OF SIPHON ASSEMBLY= 357.00
A A
INVERTED SIPHON ASSEMBLY
0451 )SCALE: N.T.S.
4 "0 PVC SIPHON ASSEMBLY
INV IN = 358.00
PIN: 0769 -03 -41 -8938 PIN: 0769 -03-41 -6932 PIN: 0769 -03-41 -4887 PIN: 0769 -0442 -5588 PIN: 0769 -03-44 -6000 PIN: 0769-03 -33 -2232 PIN: 0769-03-24-8486 PIN: 0769 -03-35 -7254 PIN: 0769 -01 -35 -3524 PIN: 0769 -01 -26 -9080 PIN: 0769-01 -06 -9898
Parcel ID: 194413 Parcel ID: 194412 Parcel ID: 194411 Parcel ID: 194383 Parcel ID: 194384 Parcel ID: 193264 Parcel ID: 193265 Parcel ID: 210697 Parcel ID: 193271 Parcel ID: 193270 Parcel ID: 193320
GROUT 4 "0 PVC INTO
WALL OF RISER
PVC INVERT IN = 358.00
4 "0 PVC SLIP CAP W11, .
3.0 "0 ORIFICE
writ n� ir•
SECTION AA
ACCESS DOOR
CENTERED OVER
STEPS
64°0 #4 REBAR RING
3" MI N
3" MIN
+
1810
O -RING RCP
1
iv
SECTION A -A
NOTES:
1. USE #4 EPDXY -COATED STEEL REBAR {TYPICAL).
2. ALLOW MINIMUM 3" BETWEEN EXPOSED CONCRETE AND REBAR.
3. PLACEMENT OF CONCRETE ANTIFLOTATION BLOCK SHALL NOT CONFLICT
WITH INSTALLATION OF 19'0 O -RING RCP.
4.INSTALL ANTI - FLOTATION BLOCK SUCH THAT rf DOES NOT CONFUCT WITH
INSTALLATION OF 18" 0 O -RING RCP.
2 RISER STRUCTURE
C451 SCALE: NTS
N
ELEVATION VIEW
NOTE: SECURE (4) EVENLY SPACED I ZV'xl /8"GALVANIZED STEEL
STRAPS 0 EACH JOINT OF RISER SECTION
NOTE: PROVIDE STEPS IN RISER PER
NCDOTSTD. 840.66 (SEE DETAIL)
3'k1/2" BOLT
12 kNkl /8" GALVIANIZED
STEEL ANCHOR STRAP
RISER JOINT
3kl/2 BOLT
NOTE: EACH STRAP TO BE SECURED TO
MANHOLE RISER BY (2) SM /2"
GALVANIZED STEEL CONCRETE ANCHOR
BOLTS. COATED WITH A BITUMINOUS
COATING.
2' MIN. COVER
FINISHE14 GRADE
RISER CREST ELEV = 362M
TO TOP OF BERM
SAND DISF.<0.7MM
FACE OF SEEPAGE
2' MIN. OUTSIDE EDGE
DISF./DRS `U0.5
2' MIN. COVER
DIAPHRAGM TO FACE
# 57 STONE
A
4''0 SCH, 40
TO TOP OF BERM
F HEADWALL
NON - PERFORATED PVCLD
PROVIDE STEPS ®11 O.C.
„
1 6''
PRECAST 4'0 EXTENDED
Y Ry
2 L.F. 4 °'0 SCH. 40
-'
i r
a. p
PER NCDOT STANDARD
�
a
PEEFORATED PVC
BASE MANHOLE
18"0 RCP
� 7ryXrv:
4.00'
410 SCH 410 PERFORATED
„
n..rSTNE°
a'
PIPE WIITH CAP
' b
MMI
N
EXTEND 4'°0 PVC
A
18 "0 O-RING RCP+x
1' -6" BASE F PIPE
THROUGH
18 "0
HEADWALL
15" 0 ORIFICE
RCP
:o
EADWALL (SEE
4°'0 SCH. 40
-�,
ry
cy
DETAIL]
INV OUT = 359.60
NON - PERFORATED PVCLD
1 " -6" BELOW BOTTOM OF 11-6" 2-171
NC PRODUCTS
PIPE
2 L.F. 4 '0 SCH. 40
DLSF. /DRS <U0.5
p.
FACE OF SEEPAGE
PRECAST 4'0 STALL EXTENDED
DIAPHRAGM TO FACE OF
PRRFORATED PVC PIPE WITH
l ZED
HEADWALL
CAP
-6
BASE MANHOLE SECTION
ELEVATION VIEW
'4
(OR APPROVED EQUAL)
NO SCALE
n
PLAN
N 0 PVC SIPHON ASSEMBLY C451
p
NO SCALE
•
INV IN = 358,00
,
9 "THICK CONCRETE FILL LAVER
.
d
{t
y t
_.
tl ll
t
4
rr
180 O -RING RCP
ft
f ,�
INV OUT 354.5D
n
EXTENDED BASE INVERT = 353.25
18 "0O -RING RCP
INV OUT = 354.50
AA
o+
BEGIN CONCRETE CRADLE AT
p
EDGE OF ANTI FLOTATION BLOCK
PLAN VIEW
64°0 #4 REBAR RING
3" MI N
3" MIN
+
1810
O -RING RCP
1
iv
SECTION A -A
NOTES:
1. USE #4 EPDXY -COATED STEEL REBAR {TYPICAL).
2. ALLOW MINIMUM 3" BETWEEN EXPOSED CONCRETE AND REBAR.
3. PLACEMENT OF CONCRETE ANTIFLOTATION BLOCK SHALL NOT CONFLICT
WITH INSTALLATION OF 19'0 O -RING RCP.
4.INSTALL ANTI - FLOTATION BLOCK SUCH THAT rf DOES NOT CONFUCT WITH
INSTALLATION OF 18" 0 O -RING RCP.
2 RISER STRUCTURE
C451 SCALE: NTS
N
ELEVATION VIEW
NOTE: SECURE (4) EVENLY SPACED I ZV'xl /8"GALVANIZED STEEL
STRAPS 0 EACH JOINT OF RISER SECTION
NOTE: PROVIDE STEPS IN RISER PER
NCDOTSTD. 840.66 (SEE DETAIL)
3'k1/2" BOLT
12 kNkl /8" GALVIANIZED
STEEL ANCHOR STRAP
RISER JOINT
3kl/2 BOLT
NOTE: EACH STRAP TO BE SECURED TO
MANHOLE RISER BY (2) SM /2"
GALVANIZED STEEL CONCRETE ANCHOR
BOLTS. COATED WITH A BITUMINOUS
COATING.
FINISHED GRADE 1
2' MIN. COVER
FINISHE14 GRADE
TO TOP OF BERM
SAND DISF.<0.7MM
FACE OF SEEPAGE
2' MIN. OUTSIDE EDGE
DISF./DRS `U0.5
2' MIN. COVER
DIAPHRAGM TO FACE
# 57 STONE
A
4''0 SCH, 40
TO TOP OF BERM
F HEADWALL
NON - PERFORATED PVCLD
SIDE)
1 6''
=n
Y Ry
2 L.F. 4 °'0 SCH. 40
-'
i r
�
HEADWALL
PEEFORATED PVC
MIN.
18"0 RCP
� 7ryXrv:
410 SCH 410 PERFORATED
n..rSTNE°
PVC (TYP)
PIPE WIITH CAP
' b
MMI
N
EXTEND 4'°0 PVC
A
18 "0 O-RING RCP+x
1' -6" BASE F PIPE
THROUGH
18 "0
HEADWALL
O-RIN
RCP
:o
EADWALL (SEE
4°'0 SCH. 40
ry
cy
DETAIL]
EXTEND DIAPHRAGM
NON - PERFORATED PVCLD
1 " -6" BELOW BOTTOM OF 11-6" 2-171
SAND DISF.<0.7MM
PIPE
2 L.F. 4 '0 SCH. 40
DLSF. /DRS <U0.5
FACE OF SEEPAGE
55
DIAPHRAGM TO FACE OF
PRRFORATED PVC PIPE WITH
l ZED
HEADWALL
CAP
-6
ELEVATION VIEW
'4
NO SCALE
PLAN
NO SCALE
FINISHED GRADE 1
2' MIN. COVER
TO TOP OF BERM
x w ;.,, ., . n.rc m..n.r :n
, +.N r,•.,r.;
2' MIN. OUTSIDE EDGE
OF PIPE TO EDGE OF
MIN.
a
DIAPHRAGM {EACH
SIDE)
1 6''
w
Y Ry
SAND
2
LAYER °
MIN.
18"0 RCP
410 SCH 410 PERFORATED
PVC (TYP)
#57 STONE
1' -6" BASE F PIPE
TO BOTTOM OF STONE
CROSS SECTION A
NO SCALE
3 SEEPAGE DIAPHRAM
C451 SCALE: N.T.S.
PRECAST FLAT TOP —
36" MIN.
CONCRETE CRADLE
(SEE CONCRETE
CRADLE PROFILE) 6°
(TYP.}
113° DIAMETER
O -RING RCP (CLASS .........Y #6 REBAR (GRADE 601
IV-MODIFIED
TONGUE &
GROOVE #3 REBAR TIES(U BARS) SPACED
w. AT 10 FT. ON CENTER
",.n n • 17 CENTER TO CENTS
,
1 1 R (TYP.)
(MIN.) (MIN.)
6" FROM BOTTOM OF CRADLE
:....:�... ......... ......... n` TO CENTER OF #d REBAR 18 "0 RCP IN FROM POND
8.583° 3' COVER (MIN.) TO p
C/C (TYP.J OUTSIDE OF #3 TIE BAR
CROSS-SECTION DETAIL
CENTER OF 76 REBAR
4 CONCRETE CRADLE DETAIL
C45 SCALE: N.T.S.
OUTSIDE DIA. CROWN OF PIPE
INSIDE DIA. CROWN OF PIPE
TOP OF CRADLE
#6 REBAR (GRADE 60)
INSIDE DIA. INV OF PIPE
OUTSIDE DIA. INVERT OF PIPE
#6 REBAR (GRADE 60)
ARE #3 REBAR(GRADE 60) SPACED
INTER ALONG THE LENGTH OF THE
2. MAINTAIN A MIN, COVER OF 3" OF CONCRETE (TO THE
OUTSIDE OF THE REBAR} FOR ALL REINFORCEMENT.
3. TRENCH TO BE BACKFILLED IN 5" LIFTS WHEN
COMPACTION IS BY HAND. BACKFILL IS IN W LIFTS WHEN
CONDUCTED BY MACHINE. MINIMUM OF 2 FEET COVER
MUST BE PRESENT ON 18 "0 RCP BEFORE DRIVING OVER WITH
HEAVY EQUIPMENT.
z
TBM SITE BENCHMARK NCGS MONUMENT
NC F EL = 409.94' NGVD 29
BYPASS WEIR
ELEV = 355.60
r ly +l
t t 1 }
t,
INV IN = 353.70 J
4'0 EXTENDED
BASE MANHOLE
SAO
ib9^
zo
4" THICK REINFORCED
CONCRETE BAFFLE WALL
GROUT TO WALLS AT BOTH ENDS
z
O
a
O
U-
Z_
b
Q
eo
FLOW SPUTTER DETAIL
C451 SCALE: N.T.S.
24" MANHOLE COVER FLUSH WITH TOP
150 RCP OUT TO LEVEL SPREADER
INV OUT = 353.60
199 BYPASS PIPE
INV OUT = 353.70
4'0 MANHOLE
150 RCP OUT TO LEVEL SPREADER
im-
CITY OF DURHAM
PUBLIC WORKS DEPARTMENT
APPROVED
ENGINEERING DATE
STORM WATER DATE
TRANSPORTATION DATE
DATE
DATE
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
■
■
■
■
■
■
■
■
■
■
■
■
■
■ HOIRVATH
■ A S S O C I A T E S
■
■ 16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
■ P 919.490.4990 F 919.490.8953
■ P.O. BOX 970
■
HARRISON, TENNESSEE 37341
P 423.266.4990
■
www.horvathassociates.com
■
NORTH CAROLINA BOARD OF
■ EXAMINERS FOR ENGINEERS AND
■ SURVEYORS LICENSE NO.: C-0676
■
■
■
■
■
■
■ J
® F- oe
7-
■ < m U
0 C
5
■ J O
Lu Lu
Lu
■
■
■
■
■
■
■ W
■ • 1 O ## 1
DETAILS
■
■
■
■
■
■
■
■
■
■
■
■
■
■ P 3R
■ � �'yG I NEED %P��� i
■ '• ...n.....•.
■
■
■
■
■
■
■
■
■
■
■
DRAWN BY: CHECKED BY:
MLJ RH/TS
■ DATE
■ APRIL 25, 2012
■ SCALE
AS NOTED
■ PROJECT NO.
Ar
■ SHEET NO.
■ C451
■
■
■ <CONSTRUCTION DRAWINGS>

WATER QUALITY POND #2 PLAN VIEW
SCALE: 1 " =30'
0 100 -YEAR WSE = 377.58
0 25 -YEAR WSE = 376.18
10 -YEAR WSE = 375.39
0 2 -YEAR WSE = 373.66
0 1 -YEAR WSE = 373.22
0 1" RUNOFF VOLUME WSE = 372.40 =
DEEP POOL BOTTOM = 367.00
HAND WHEEL
2' WIDE X 2' TALL ORIFICE
INV = 372.40
INVERTED 4'0
SIPHON ASSEMBLY
INV = 371.00
,Al PC)C)I = 371 [10
7 LF 9'0 DIP
6 .00
WATER QUALITY POND #2 PROFILE VIEW
C452 %SCALE: N.T.S.
5�
1l
`l
t�
ti
0 15 30 60
SCALE: 1 30'
RISER CREST 3
ELEVATION = 375.30 1
INVERT OUT = 367.00
12' WIDE BERM
TOP OF BERM = 380.00
(SEEMED = 379.351
88 LF 36"0 O -RING RCP @ 1.099
F rzartcruie.��x \ J
eme�vgwcwx�rnonwuoe
mum
1114�� ��
3
,r
FLOW SPUTTER MANHOLE
t�
BYPASS WEIR
ELEVATION = 369.40
i
;-
36" 0 RCP BYPASS PIPE
INV OUT = 366.00
nr�
INV OUT = 365.90
n HEADWALL
r/ INVERT = 365.60
26 LF 15 "0 RCP T0' WIDE
:.
LINEAR WETLAND
t�
1,
Lim
am
t,
1,
/-LEVEL SPREADER LIP
INVERT = 366.00
TBM SITE BENCHMARK NCGS MONUMENT
NC F EL = 409.94' NGVD 29
FILTER STRIP JUST DOWNSTREAM OF LEVEL SPREADER LIP
ELEVATION = 365.70
END OF ENGINEERED FILTER STIP
ELEVATION = 364.00
CITY OF DURHAM
PUBLIC WORKS DEPARTMENT
APPROVED
ENGINEERING DATE
STORM WATER DATE
TRANSPORTATION DATE
DATE
nATF
I
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
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HOIRVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.horvathassociates.com
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
WO #2
PLAN
C)� E s
P
� co
• T'vG I NEED %P��� i
� 4 J
Z O • Ho,.••'�
DRAWN BY: CHECKED BY:
MLJ RH/TS
DATE
APRIL 25, 2012
SCALE
AS NOTED
PROJECT NO.
1121
SHEET NO.
C452
<CONSTRUCTION DRAWINGS>
V)
ry
0
rn
rn
rl000
J
cn
<
®
F-
oe 0
l3e
0
J
II-
O
9_u
_
J�
s
_
C)
Lu
W
<
r
ne
1)
WO #2
PLAN
C)� E s
P
� co
• T'vG I NEED %P��� i
� 4 J
Z O • Ho,.••'�
DRAWN BY: CHECKED BY:
MLJ RH/TS
DATE
APRIL 25, 2012
SCALE
AS NOTED
PROJECT NO.
1121
SHEET NO.
C452
<CONSTRUCTION DRAWINGS>

4 "0 PVC CLEANOUT
WITH REMOVABLE CAP
TOP OF SIPHON ASSEMBLY = 371.20
4"o PVC
4" X4 "X4" PVC TEE
4110 PVC
BOTTOM OF SIPHON ASSEMBLY= 367.00 1
A A
INVERTED SIPHON ASSEMBLY
C452% SCALE: N.T.S.
3490 O -RING RCP
INV OUT = 366.00
PLAN VIEW
2 RISER STRUCTURE
0452 SCALE: NTS
GROUT 4 "0 PVC INTO
WALL OF RISER
PVC INVERT IN = 368.00
RISER CREST ELIEV = 375.30
PIN: 0769 -03 -41 -8938 PIN: 0769 -03-41 -6932 PIN: 0769 -03-41 -4887 PIN: 0769 -0442 -5588 PIN: 0769 -03-44 -6000 PIN: 0769-03 -33 -2232 PIN: 0769-03-24-8486 PIN: 0769 -03-35 -7254 PIN: 0769 -01 -35 -3524 PIN: 0769 -01 -26 -9080 PIN: 0769-01 -06 -9898
Parcel ID: 194413 Parcel ID: 194412 Parcel ID: 194411 Parcel ID: 194383 Parcel ID: 194384 Parcel ID: 193264 Parcel ID: 193265 Parcel ID: 210697 Parcel ID: 193271 Parcel ID: 193270 Parcel ID: 193320
4 "o PVC
SECTION AA
N
ELEVATION VIEW
PROVIDE STEPS ®16' O.C.
PER NCDOT STANDARD
NC PRODUCTS
PRECAST 5'0 5' TALL EXTENDED
BASE MANHOLE SECTION
(OR APPROVED EQUAL)
5.33 THICK CONCRETE FILL LAYER
PLACE EXTENDED BASE MANHOLE ON
COMPACTED SUBGRADE
NOTE: SECURE (4) EVENLY SPACED 12°x4'xl /8" GALVANIZED STEEL
STRAPS 0 EACH JOINT OF RISER SECTION
NOTE: PROVIDE STEPS IN RISER PER
NCDOTSTD. 840.66 (SEE DETAIL)
3'x1/2" BOLT
12"xNkl /8" GALVIANIZED
STEEL ANCHOR STRAP
RISER JOINT
3'x1/2" BOLT
NOTE: EACH STRAP TO BE SECURED TO
MANHOLE RISER BY (2) SM /2"
GALVANIZED STEEL CONCRETE ANCHOR
BOLTS. COATED WITH A BITUMINOUS
COATING.
FINISHED GRADE 1
2' MIN. COVER
FINISHE14 GRADE
TO TOP OF BERM
SAND DISF. <0.7MM
FACE OF SEEPAGE
2' MIN. OUTSIDE EDGE
DISF./DRS `U0.5
2' MIN. COVER
DIAPHRAGM TO FACE
# 57 STONE
A
4''0 SCH, 40
TO TOP OF BERM
F HEADWALL
NON - PERFORATED PVCLD
SIDE)
1 6''
=n
Y Ry
2 L.F. 4 °'0 SCH. 40
-'
i r
�
HEADWALL
PREFORATED PVC
MIN.
38"0 RCP
� 7ryXrv:
4'0 SCH 40 PERFORATED
n. :SINE°
PVC (TYP)
PIPE WITH CAP
' b
MMI
N
EXTEND 4°0 PVC
A
36 "9 O -RING RCP+x
1' -6" BASE 4F PIPE
THROUGH
C36" 0
HEADWALL
O-RIN
RCP
:o
EADWALL (SEE
4 °'0 SCH. 40
ry
ry cy
DETAIL)
EXTEND DIAPHRAGM
NON - PERFORATED PVCLD
1 " -6" BELOW BOTTOM OF 1' 6" 2'-0°'
SAND DISF.<0.7MM
PIPE
2 L.F. 4 '0 SCH. 40
DLSF. /DRS <UO.5
FACE OF SEEPAGE
55
DIAPHRAGM TO FACE OF
PREFORATED PVC PIPE WITH
„
HEADWALL
CAP
-1-6 2-0 1
ELEVATION VIEW
'4
NO SCALE
PLAN
NO SCALE
FINISHED GRADE 1
2' MIN. COVER
TO TOP OF BERM
x w ;•,, ., . n.rc m..n.r :n
,,.N :..,r.:
2' MIN. OUTSIDE EDGE
OF PIPE TO EDGE OF
MIN.
a
DIAPHRAGM {EACH
SIDE)
1 6''
w
Y Ry
SAND
2'
LAYER °
MIN.
38"0 RCP
4'0 SCH 40 PERFORATED
PVC (TYP)
#57 STONE
1' -6" BASE 4F PIPE
TO BOTTOM OF STONE
CROSS SECTION A
NO SCALE
3 SEEPAGE DIAPHRAGM
C452 SCALE: N.T.S.
TBM SITE BENCHMARK NCGS MONUMENT
NC F EL = 409.94' NGVD 29
PRECAST FLAT TOP MANHOLE COVER FLUSH WITH TOP
56 °'MIN.
CONCRETE CRADLE
(SEE CONCRETE
CRADLE PROFILE)
(TYP.)
36" DIAMETER
O -RING RCP (CLASS 60 MANHOLE
IV- MODIFIED z #6 REBAR (GRADE 601
TONGUE &
GROOVE #3 REBAR TIES(U -BARS) SPACED BYPASS WEIR
N AT 10 FT. ON CENTER
ELEV = 369.40
1 1
,.n M • 27 CENTER TO CENTS
1 m (TY ' }
7 h4
wr
1
(MIN.) (MIN.)
z 6" FROM BOTTOM OF CRADLE
io
rr ~
36°'0 RCP IN FROM POND
........ TO CENTER OF #d REBAR i 1 B' 0 RC LEVEL SPREADER
,....... ........ ......... ...........
8,583° 3" COVER QMIN.) TO P OUT TO L
C/C (TYP.J OUTSIDE OF #3 TIE BAR t t f
ti
CROSS-SECTION DETAIL
INV IN = 366.00 INV OUT = 365.90
_ 12 PIPE SECTION DETAIL _
CENTER OF #6 REBAR -- ­
4 CONCRETE CRADLE DETAIL
C452 SCALE: N.T.S.
OUTSIDE DIA. CROWN OF PIPE
INSIDE DIA. CROWN OF PIPE
TOP OF CRADLE
#6 REBAR (GRADE 60)
INSIDE DIA. INV OF PIPE
OUTSIDE DIA. INVERT OF PIPE
#6 REBAR (GRADE 60)
ARE #3 REBAR(GRADE 60) SPACED
INTER ALONG THE LENGTH OF THE
2. MAINTAIN A MIN, COVER OF 3" OF CONCRETE (TO THE
OUTSIDE OF THE REBAR} FOR ALL REINFORCEMENT.
3. TRENCH TO BE BACKFILLED IN 5" LIFTS WHEN
COMPACTION IS BY HAND. BACKFILL IS IN 8" LIFTS WHEN
CONDUCTED BY MACHINE. MINIMUM OF 2 FEET COVER
MUST BE PRESENT ON 18 "0 RCP BEFORE DRIVING OVER WrrH
HEAVY EQUIPMENT.
4" THICK REINFORCED
CONCRETE BAFFLE WALL
GROUT TO WALLS AT BOTH ENDS
in
z
O
a
0
ne
Z_
d
:o
M
5 FLOW SPUTTER DETAIL
C453 SCALE: N.T.S.
36 "0 BYPASS PIPE
INV OUT = 366.00
50 MANHOLE
18" 0 RCP OUT TO LEVEL SPREADER
CITY OF DURHAM
PUBLIC WORKS DEPARTMENT
APPROVED
ENGINEERING DATE
STORM WATER DATE
TRANSPORTATION DATE
DATE
nATF
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
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H01IRVATH
■ A S S O C I A T E S
■
■ 16 CONSULTANT PLACE,SUTTE 201
DURHAM, NORTH CAROLINA 27707
■ P 919.490.4990 F 919.490.8953
■ P.O. BOX 970
■
HARRISON, TENNESSEE 37341
P 423.266.4990
■
www.horvathassociates.com
■
NORTH CAROLINA BOARD OF
■ EXAMINERS FOR ENGINEERS AND
■ SURVEYORS LICENSE NO.: C-0676
0 <
■
■
■
■
■
■
® F- oe
■ 0 m U
� 0
�
■ o Op
■ J O
• Lu �_�
LU
0 <
■ ne
■ r
■
■
■
■
■ WO #2
DETAILS
■
■
■
■
■
■
■
■
■
■
■
■
■
■
CA R
0,
7''• Y
■ P 3R
■ � �'vG I NEED %P��� i
tiI`I► "N� � O L • H0� �����•
■ '•�...n.....•.
■
■
■
■
■
■
■
■
■
■
■
DRAWN BY: CHECKED BY:
MLJ RH/TS
■ DATE
■ APRIL 25, 2012
■ SCALE
AS NOTED
■ PROJECT NO.
■ SHEET NO.
C453■
■
■ <CONSTRUCTION DRAWINGS>

............ ... ............. ...
............. .
HW
INV = 402.00
RISER--`
I N OUT= 4C .00 -` CL
Q
u
�Fop OF BERM = 410.00
� DRY POND
0454
#3 PLAN VIEW
v 100 -YEAR WSE = 407.44 v 25-YEAR WSE = 407-16
'--�DRY POND
C454 SCALE: N.T.S.
CONCRETE FILL LAYER ON TOP OF FLAT TOP
TO MAKE FLUSH WITH MANHOLE
PRECAST FLAT TOP WIT H
24!9 MANHOLE OPENING
10"0 ORIFICE
INV = 405.00
t N
4.00'
INVERTED SIPHON
ASSEMBLY
WITH 2.0 0 ORIFICE
INV = 402.00
MICROPOOL
BOTTOM = 400.00
7E� E� 7
2 r-
0 10 20 40
SCALE: 1 20'
TOP OF RISER
ELEVATION = 408.00
3
OUT = 402D0
1 VWIDE BERM
u-
-A
56 LF 19'0 O-RING RCP 0 1.07%
E
C� c
SrIF B CC:­ 1 -1 N �Gll 11 E YR
3
7 N D JA_F�f M
7
-��III III III III III III III III III III III III III III III III III III III III III
#3 PROFILE VIEW
HEADWALL
INVERT = 401.40
10' WIDE
LINEAR WE•L
. .............. ............................. ............................... ............................. ................... .................. ■
■
DRY POND #3
PLAN
■ PR
oil
ot, - --'z-
-p
■
■
■
■
LEVEL SPREADER LIP
INVERT = 401.30 ■
//-FILTER STRIP JUST DOWNSTREAM OF LEVEL SPREADER UP ■
ELEVATION = 401.00
■
END OF ENGINEERED FILTER STIP
ELEVATION = 399.00 ■
■
7N i,77- 7 7 d,
DRAWN BY: CHECKED BY:
MLJ RH/TS
■ DATE
■ APRIL 25, 2012
■ SCALE AS NOTED
■
CITY OF DURHAM ■ PROJECT NO.
PUBLIC WORKS DEPARTMENT 1121
APPROVED ■ SHEET NO.
ENGINEERING DATE
■
STORM WATER DATE
TRANSPORTATION DATE C454
DATE ■
DATE <CONSTRUCTION DRAWINGS>
@COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED

TOP OF SIPHON ASSEMBLY
4"o PVC
4 1'X4 "X4" PVC TEE
4 "0 PVC
PVC SLIP CAP WITH 70
ORIFICE CEMENTED ONTO
END OF 4 "0 PVC SECTION
BOTTOM OF SIPHON ASSEMBI
A "f'X n\ /1 y f^ I r A A If-% 1 IT
A A
INVERTED SIPHON ASSEMBLY
C455I SCALE: N.T.S.
PIN: 0769 -03 -41 -8938 PIN: 0769 -03-41 -6932 PIN: 0769 -03-41 -4887 PIN: 0769 -0442 -5588 PIN: 0769 -03-44 -6000 PIN: 0769-03 -33 -2232 PIN: 0769-03-24-8486 PIN: 0769 -03-35 -7254 PIN: 0769 -01 -35 -3524 PIN: 0769 -01 -26 -9080 PIN: 0769-01 -06 -9898
Parcel ID: 194413 Parcel ID: 194412 Parcel ID: 194411 Parcel ID: 194383 Parcel ID: 194384 Parcel ID: 193264 Parcel ID: 193265 Parcel ID: 210697 Parcel ID: 193271 Parcel ID: 193270 Parcel ID: 193320
GROUT 4 "0 PVC INTO
WALL OF RISER
NVERT IN = 402.00
4 "0 PVC SLIP CAP W11, .
2.0 "0 ORIFICE
A"f7[ nx if—
SECTION AA
PROVIDE 8" THIICKCONCRETE FILL LAYER ON
FLAT TOP TO MAKE TOP FLUSH WITH
0455 4 "0 PVC SIPHON ASSEMBLY MANHOLE COVER
INV IN = 402.00
O TOP OF MANHOLE
-
ELEV = 409.00
� n
0
2.00' h
4.
q PRECAST 4'0 EXTENDED
BASE MANHOLE
A' ? Y
a
r
BOLT MANHOLE FRAME TO FLAT TOP
NC PRODUCTS
40 PRECAST FLAT TOP
(OR APPROVED EQUAL)
PROVIDE STEPS 016" O.C.
PER NCDOT STANDARD
h
10'9 ORIFICE
INV OUT = 405,00 INC PRODUCTS
.~ PRECAST 4'0 5' TALL EXTENDED
4 0 PVC SIPHON ASSEMBLY 1 tf BASE MANHOLE SECTION
p
WITH 2 0 0 ORIFICE C455 f `1 `l (OR APPROVED EQUAL)
PLAN VIEW
64 70 #4 REBAR RING
3" MIN
3" MIN
18'Y�J
O -RING RCP
f' 15" �T� 12 �T� 12" � � 17 °�r� 1T i 15"
SECTION A -A
CV
z�
In
NOTES:
1. USE #4 EPDXY -COATED STEEL REBAR (TYPICAL).
2. ALLOW MINIMUM 3'° BETWEEN EXPOSED CONCRETE AND REBAR.
3. PLACEMENT OF CONCRETE ANTIFLOTATION BLOCK SHALL NOT CONFLICT
WITH INSTALLATION OF IW 0 O -RING RCP.
41NSTALL ANTI - FLOTATION BLOCK SUCH THAT IT DOES NOT CONFLICT WIT H
INSTALLATION OF 19'0 O -RING RCP.
2 RISER STRUCTURE
C455 SCALE: NTS
N
MIS
ELEVATION VIEW
NOTE: SECURE (4) EVENLY SPACED I ZV'xl /8"GALVANIZED STEEL
STRAPS 0 EACH JOINT OF RISER SECTION
NOTE: PROVIDE STEPS IN RISER PER
NCDOTSTD. 840.66 (SEE DETAIL)
3'k1/2" BOLT
12"xNkl /8" GALVIANIZED
STEEL ANCHOR STRAP
RISER JOINT
�3'kl/2" BOLT
NOTE: EACH STRAP TO BE SECURED TO
MANHOLE RISER BY (2) SM /2"
GALVANIZED STEEL CONCRETE ANCHOR
BOLTS. COATED WITH A BITUMINOUS
COATING.
f
INV IN — 402,00 ,4
ry
m
i t
o e ,
FACE OF SEEPAGE
4 1 l f 7
ry.
2' MIN. COVER
DIAPHRAGM TO FACE
# 57 STONE
f
1 B"0 O -RING RCP t
LFL,F, 4 "QS SCH, 40
y
TO TOP OF BERM
F HEADWALL
=
INV OUT 402.00
NON - PERFORATED PVCLD
®F-
E7T]61I
Lu
=n
7—
71
EXTENDED BASE INVERT = 400.75
18 "0 0 -RING RCP
2 L.F. 4 °'0 SCH. 40
-'
i �
o
INV OUT = 402.00
HEADWALL
PEEFORATED PVC
n
A A
io
9_9..9
�# 7 °.
s�
_
BEGIN GONGRETE CRADLE AT T
SINE
PIPE WIITH CAP
' b
EDGE OF ANTI FLOTATION BLOCK
PLAN VIEW
64 70 #4 REBAR RING
3" MIN
3" MIN
18'Y�J
O -RING RCP
f' 15" �T� 12 �T� 12" � � 17 °�r� 1T i 15"
SECTION A -A
CV
z�
In
NOTES:
1. USE #4 EPDXY -COATED STEEL REBAR (TYPICAL).
2. ALLOW MINIMUM 3'° BETWEEN EXPOSED CONCRETE AND REBAR.
3. PLACEMENT OF CONCRETE ANTIFLOTATION BLOCK SHALL NOT CONFLICT
WITH INSTALLATION OF IW 0 O -RING RCP.
41NSTALL ANTI - FLOTATION BLOCK SUCH THAT IT DOES NOT CONFLICT WIT H
INSTALLATION OF 19'0 O -RING RCP.
2 RISER STRUCTURE
C455 SCALE: NTS
N
MIS
ELEVATION VIEW
NOTE: SECURE (4) EVENLY SPACED I ZV'xl /8"GALVANIZED STEEL
STRAPS 0 EACH JOINT OF RISER SECTION
NOTE: PROVIDE STEPS IN RISER PER
NCDOTSTD. 840.66 (SEE DETAIL)
3'k1/2" BOLT
12"xNkl /8" GALVIANIZED
STEEL ANCHOR STRAP
RISER JOINT
�3'kl/2" BOLT
NOTE: EACH STRAP TO BE SECURED TO
MANHOLE RISER BY (2) SM /2"
GALVANIZED STEEL CONCRETE ANCHOR
BOLTS. COATED WITH A BITUMINOUS
COATING.
FINISHED GRADE 1
2' MIN. COVER
TO TOP OF BERM
x w ;,,, .°, . n.rc m..n.r :n ,,.N r,•.,r.; 2' MIN. OUTSIDE EDGE
OF PIPE TO EDGE OF
LMI�N/.a,, DIAPHRAGM {EACH
SIDE)
1 6 /��% Y R•
SAND w�2'
18"0 RCP 4'0 SCH 40 PERFORATED
PVC (TYP)
#57 STONE
TO BOTTOM OF STONE
CROSS SECTION A
NO SCALE
3 SEEPAGE DIAPHRAM
C455 SCALE: N.T.S.
36" MIN.
CONCRETE CRADLE
(SEE CONCRETE
CRADLE PROFILE)
(TYP.)
18'° DIAMETER
n O -RING RCP (CLASS
................ #6 REBAR (GRADE 601
IV-MODIFIED
TONGUE &
GROOVE #3 REBAR TIES(U BARS) SPACED
w. AT 10 FT. ON CENTER
1� m 1
",.n w n • 17 CENTER TO CENTS
, n rcr
1 1 R (TYP.)
(MIN.) (MIN.)
L 6" FROM BOTTOM OF CRADLE
...... ............n TO CENTER OF #6 REBAR
8 583 3" COVER (MIN.) TO
C/C (TYP.J OUTSIDE OF #3 TIE BAR
CROSS-SECTION DETAIL
CENTER OF 76 REBAR
4 CONCRETE CRADLE DETAIL
C455 SCALE: N.T.S.
OUTSIDE DIA. CROWN OF PIPE
INSIDE DIA. CROWN OF PIPE
TOP OF CRADLE
#6 REBAR (GRADE 60)
INSIDE DIA, INV OF PIPE
OUTSIDE DIA. INVERT OF PIPE
#6 REBAR (GRADE 60)
ARE #3 REBAR(GRADE 60) SPACED
INTER ALONG THE LENGTH OF THE
2. MAINTAIN A MIN, COVER OF 3" OF CONCRETE (TO THE
OUTSIDE OF THE REBAR) FOR ALL REINFORCEMENT.
3. TRENCH TO BE BACKRLLED IN 5" UFTS WHEN
COMPACTION IS BY HAND. BACKFILL IS IN W LIFTS WHEN
CONDUCTED BY MACHINE. MINIMUM OF 2 FEET COVER
MUST BE PRESENT ON 18 "0 RCP BEFORE DRIVING OVER WITH
HEAVY EQUIPMENT.
TBM SITE BENCHMARK NCGS MONUMENT
NC F EL = 409.94' NGVD 29
CITY OF DURHAM
PUBLIC WORKS DEPARTMENT
APPROVED
ENGINEERING DATE
STORM WATER DATE
TRANSPORTATION DATE
DATE
HATE
I
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
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H01IRVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.horvathassociates.com
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
FINISHE14 GRADE
ry
SAND DISF.<0.7MM
FACE OF SEEPAGE
DISF `U0.5
2' MIN. COVER
DIAPHRAGM TO FACE
# 57 STONE
A
LFL,F, 4 "QS SCH, 40
-/DRS
TO TOP OF BERM
F HEADWALL
J
NON - PERFORATED PVCLD
®F-
oe
Lu
=n
7—
2 L.F. 4 °'0 SCH. 40
-'
i �
o
n' -
HEADWALL
PEEFORATED PVC
n
O
9_9..9
�# 7 °.
s�
_
SINE
PIPE WIITH CAP
' b
_
N
EXTEND 4'°0 PVC
A
18 "0 OWING RCPix
THROUGH
HEADW ALL
LRING
RCP
:o
EADWALL (SEE
LF2L.F. 4 10 SC91.40
ry
cy
DETAIL]
EXTEND DIAPHRAGM
NON - PERFORATED PVCLD
1 " -6" BELOW BOTTOM OF 1'-6" 2'-0°'
SAND DISF,<0.7MM
PIPE
2 L.F. 4 '0 SCH, 40
DLSF. /DRS <UD.5
y
FACE OF SEEPAGE
DIAPHRAGM TO FACE OF
PRRFORATED PVC PIPE WITH
ZED n,
HEADWALL
CAP
ELEVATION VIEW
A
NO SCALE
PLAN
NO SCALE
FINISHED GRADE 1
2' MIN. COVER
TO TOP OF BERM
x w ;,,, .°, . n.rc m..n.r :n ,,.N r,•.,r.; 2' MIN. OUTSIDE EDGE
OF PIPE TO EDGE OF
LMI�N/.a,, DIAPHRAGM {EACH
SIDE)
1 6 /��% Y R•
SAND w�2'
18"0 RCP 4'0 SCH 40 PERFORATED
PVC (TYP)
#57 STONE
TO BOTTOM OF STONE
CROSS SECTION A
NO SCALE
3 SEEPAGE DIAPHRAM
C455 SCALE: N.T.S.
36" MIN.
CONCRETE CRADLE
(SEE CONCRETE
CRADLE PROFILE)
(TYP.)
18'° DIAMETER
n O -RING RCP (CLASS
................ #6 REBAR (GRADE 601
IV-MODIFIED
TONGUE &
GROOVE #3 REBAR TIES(U BARS) SPACED
w. AT 10 FT. ON CENTER
1� m 1
",.n w n • 17 CENTER TO CENTS
, n rcr
1 1 R (TYP.)
(MIN.) (MIN.)
L 6" FROM BOTTOM OF CRADLE
...... ............n TO CENTER OF #6 REBAR
8 583 3" COVER (MIN.) TO
C/C (TYP.J OUTSIDE OF #3 TIE BAR
CROSS-SECTION DETAIL
CENTER OF 76 REBAR
4 CONCRETE CRADLE DETAIL
C455 SCALE: N.T.S.
OUTSIDE DIA. CROWN OF PIPE
INSIDE DIA. CROWN OF PIPE
TOP OF CRADLE
#6 REBAR (GRADE 60)
INSIDE DIA, INV OF PIPE
OUTSIDE DIA. INVERT OF PIPE
#6 REBAR (GRADE 60)
ARE #3 REBAR(GRADE 60) SPACED
INTER ALONG THE LENGTH OF THE
2. MAINTAIN A MIN, COVER OF 3" OF CONCRETE (TO THE
OUTSIDE OF THE REBAR) FOR ALL REINFORCEMENT.
3. TRENCH TO BE BACKRLLED IN 5" UFTS WHEN
COMPACTION IS BY HAND. BACKFILL IS IN W LIFTS WHEN
CONDUCTED BY MACHINE. MINIMUM OF 2 FEET COVER
MUST BE PRESENT ON 18 "0 RCP BEFORE DRIVING OVER WITH
HEAVY EQUIPMENT.
TBM SITE BENCHMARK NCGS MONUMENT
NC F EL = 409.94' NGVD 29
CITY OF DURHAM
PUBLIC WORKS DEPARTMENT
APPROVED
ENGINEERING DATE
STORM WATER DATE
TRANSPORTATION DATE
DATE
HATE
I
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
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H01IRVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.horvathassociates.com
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
DRY POND #3
DETAILS
CA
R:
P
3 '
• T'vG I NEED %PT� i
L. HO-,,o%
DRAWN BY: CHECKED BY:
MLJ RH/TS
DATE
APRIL 25, 2012
SCALE
AS NOTED
PROJECT NO.
1121
SHEET NO.
C455
<CONSTRUCTION DRAWINGS>
ry
Z
J
®F-
oe
Lu
7—
o
J
O
9_9..9
_
u
s�
_
Lu
Lu
fie
DRY POND #3
DETAILS
CA
R:
P
3 '
• T'vG I NEED %PT� i
L. HO-,,o%
DRAWN BY: CHECKED BY:
MLJ RH/TS
DATE
APRIL 25, 2012
SCALE
AS NOTED
PROJECT NO.
1121
SHEET NO.
C455
<CONSTRUCTION DRAWINGS>

x-
LEERED�
LF ljg'
I
■
rr
r � r v .� r � _ f%1:00
/.,.
�
0 10 20 40 ■
WATER QUALITY POND #4 PLAN VIEW
C456
4SCALE' 1 "=20' SCALE: 1 20' ■
■
■
■
CONCRETE FILL LAYER ON TOP OF FLAT TOP
TO MAKE FLUSH WITH MANHOLE 12' WIDE BERM
��\A ai;Q
TOP OP OF BERM = 386.00
PRECAST FLAT TOP Wff
(SEMED 385 A&l
24'0 MANHOLE OPENING
TOP OF STRUCTURE
100 -YEAR WSE = 383.63 ELEVATION = 383.30
c C,�q�l
..................
57
,7 25-YEAR WSE 383.10 OORIFICE c ::::::::: Ml
10 -YEAR WSE 382.69 INV = 381.60
1 3 ZOL
2-YEAR WSE 382.03 4.00
1-YEAR WSE =381.88 INVERTED SIPHON ASSEMBLY ■
WITH l.Cf'O ORIFICE
1 RUNOFF VOLUME WSE 381-60 INV 381.00
NORMAL POOL = 381.00
■
z
HEADWALL LEVEL SPREADER UP
INVERT = 376.00
2 INVERT 375.20 ■
12 LF 8'0 DIP INVERT OUT 376.00 FILTER STRIP JUST DOWNSTREAM OF LEVEL SPREADER LIP ■
DEEP POOL BOTTOM 375.00 66 LF 18"0 O-RING RCP @ 1.21 %
ELEVATION = 375.70 ■
�N = 376
-i.
w END OF ENGINEERED FILTER STIP
. . ... .. . ....
10'WIDE
ELEVATION 374.00
LINEAR
WETLAND
IT ANDL
-1 T7-
L WETLAND ■ F7, ■
r,
�RENC-H RETE-Fl L �Y� 457 E T 0 DRAWN BY: CHECKED BY:
I .......... .......... .......... ........... — ..........
��T �HNIICAL�E �—IIEER T MLJ RH/TS
I�p
H �R�
4 S DATE APR1 25, 2012
■ SCALE AS NOTED
■
CITY OF DURHAM PROJECT' NO. ■ PUBLIC WORKS DEPARTMENT 1121
APPROVED ■ SHEET NO.
2 WATER QUALITY POND #4 PROFILE VIEW ENGINEERING DATE
STORM WATER DATE
C456SCALE: N.T.S. TRANSPORTATION DATE C456
DATE ■
DATE <CONSTRUCTION DRAWINGS>
@COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED

4 "0 PVC CLEANOUT
WITH REMOVABLE CAP
TOP OF SIPHON ASSEMBLY = 382.50
4"o PVC
4" X4 "X4" PVC TEE
4 "0 PVC
PVC SLIP CAP WITH 1"0
ORIFICE CEMENTED ONTO
END OF 4 "0 PVC SECTION
BOTTOM OF SIPHON ASSEMBLY= 380.00
A A
INVERTED SIPHON ASSEMBLY
C457) SCALE: N.T.S.
PIN: 0769 -03 -41 -8938 PIN: 0769 -03-41 -6932 PIN: 0769 -03-41 -4887 PIN: 0769 -0442 -5588 PIN: 0769 -03-44 -6000 PIN: 0769-03 -33 -2232 PIN: 0769-03-24-8486 PIN: 0769 -03-35 -7254 PIN: 0769 -01 -35 -3524 PIN: 0769 -01 -26 -9080 PIN: 0769-01 -06 -9898
Parcel ID: 194413 Parcel ID: 194412 Parcel ID: 194411 Parcel ID: 194383 Parcel ID: 194384 Parcel ID: 193264 Parcel ID: 193265 Parcel ID: 210697 Parcel ID: 193271 Parcel ID: 193270 Parcel ID: 193320
GROUT 4 "0 PVC INTO
WALL OF RISER
PVC INVERT IN = 381.00
4 "0 PVC SLIP CAP WIT,.
1.0 "0 ORIFICE
SECTION AA
PROVIDE 8" THICKCONCRETE FILL LAYER ON
FLAT TOP TO MAKE TOP FLUSH WITH
MANHOLE COVER
TOP OF MANHOLE
ELEV = 385.30 10
2.00' /r
4.00' �L
r r r
OPEN TO C457 4"0 PVC SIPHON ASSEMBLY
OPERATE VALVE INV IN = 381.00
4
' PRECAST
BBASE MANHO LE
EXTENDED
i 4•
24"0 MANHOLE
OPENING
18"0 O -RING RCP
INV OUT = 376.00
PLAN VIEW
4 RISER STRUCTURE
0457 SCALE: NTS
N
?ll■
ELEVATION VIEW
# 57 STONE
2 L.F. 4 "9 SCH. 40
PEEFORATED PVC
PIPE WIITH CAP -
18"0
O-RI1
SAND DISF.<0.7MM
DISF. /DRS <UO.5
PLAN
NO SCALE
=n
b
[V
FINISHE14 GRADE
SAND DISF. <0.7MM FACE OF SEEPAGE
DISF./DRS <U0.5 2' MIN. COVER DIAPHRAGM TO FACE
4'0 SCH, 40 — TO TOP OF BERM F HEADWALL
NON - PERFORATED PVCLD
�HEADWALL
-A rr .S oNEry
EXTEND 4"0 PVC
THROUGH
HEADWALL
1 ' ! _--HEADWALL (SEE
r" DETAIL
tj :Q FACE OF SEEPAGE
DIAPHRAGM TO FACE OF
HEADWALL
EXTEND DIAPHRAGM
l' -6" BELOW BOTTOM
PIPE
18 "0 O-RING RCP
'ro" 2!-0"
ELEVATION VIEW
NO SCALE
FINISHED GRADE 1
2' MIN. COVER
TO TOP OF BERM
x w ;,,, .�, . n.rc m..n.r :n ,,.N r,•.,r.; 2' MIN. OUTSIDE EDGE
OF PIPE TO EDGE OF
MIN.a DIAPHRAGM {EACH
SIDE)
SAND w�2'
u�rtrc° avun. 11 18"0 RCP 4" O SCH 40 PERFORATED
PVC (TYP)
#57 STONE
1' -6" BASE F PIPE
TO BOTTOM OF STONE
BOLT MANHOLE FRAME TO FLAT TOP
CROSS SECTION A
INC PRODUCTS NO SCALE
XO PRECAST FLAT TOP
(OR APPROVED EQUAL) 3 SEEPAGE DIAPHRAM
C457 SCALE: N.T.S.
PROVIDE STEPS ®16" O.C.
PER NCDOT STANDARD
NC PRODUCTS
PRECAST 4'0 5' TALL EXTENDED
BASE MANHOLE SECTION
(OR APPROVED EQUAL) 36" MIN,
CONCRETE CRADLE
(SEE CONCRETE
CRADLE PROFILE)
2.5'THICKCONCRErE FILL LAYER (TYP.)
188' DIAMETER
m O -RING RCP (CLASS ...........Y #6 REBAR (GRADE 601
IV - MODIFIED
TONGUE &
GROOVE #3 REBAR TIES(U -BARS) SPACED
AT 10 FT. ON CENTER
",.n n • 17 CENTER TO CENTER P.
1 , m n rcr (TY )
1
ELEV = 373.00 (MIN.)
(MIN.) 6" FROM BOTTOM OF CRADLE
Ak ..... :.....�... ,......: ........
............. TO CENTER OF #6 REBAR
8,583 3" COVER (MIN.) TO
C/C (TYp.J OUTSIDE OF #3 TIE BAR
- PLACE EXTENDED BASE MANHOLE ON CROSS - SECTION DETAIL
COMPACTED SUBGRADE
_ 12 PIPE SECTION DETAIL _
NOTE:SECURE(4) EVENLYSPACED IZV'xl /8 "GALVANIZED STEEL
STRAPS 0 EACH JOINT OF RISER SECTION
NOTE: PROVIDE STEPS IN RISER PER
NCDOTSTD. 840.66 (SEE DETAIL)
3'kl/2" BOLT
12"xNkl /8" GALVIANIZED
STEEL ANCHOR STRAP
RISER JOINT
\--3'kl/2" BOLT
NOTE: EACH STRAP TO BE SECURED TO
MANHOLE RISER BY (2) SM /2"
GALVANIZED STEEL CONCRETE ANCHOR
BOLTS. COATED WITH A BITUMINOUS
COATING.
CENTER OF #6 REBAR -- ­
4 CONCRETE CRADLE DETAIL
0457 SCALE: N.T.S.
tm, ° :o
o 4lSCH. 40
- NON - PERFORATED PVCLD
OUTSIDE DIA. CROWN OF PIPE
INSIDE DIA. CROWN OF PIPE
TOP OF CRADLE
#6 REBAR (GRADE 60)
INSIDE DIA. INV OF PIPE
OUTSIDE DIA. INVERT OF PIPE
#6 REBAR (GRADE 60)
ARE #3 REBAR(GRADE 60) SPACED
INTER ALONG THE LENGTH OF THE
2. MAINTAIN A MIN, COVER OF 3" OF CONCRETE (TO THE
OUTSIDE OF THE REBAR} FOR ALL REINFORCEMENT.
3. TRENCH TO BE BACKFILLED IN 5" LIFTS WHEN
COMPACTION IS BY HAND. BACKFILL IS IN W LIFTS WHEN
CONDUCTED BY MACHINE. MINIMUM OF 2 FEET COVER
MUST BE PRESENT ON 18 "0 RCP BEFORE DRIVING OVER WrrH
HEAVY EQUIPMENT.
TBM
■
SITE BENCHMARK NCGS MONUMENT
■
NC F EL = 409.94' NGVD 29
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CITY OF DURHAM
PUBLIC WORKS DEPARTMENT
■
APPROVED
■
ENGINEERING DATE
■
STORM WATER DATE
TRANSPORTATION DATE
■
DATE
■
DATE
■
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
HOIRVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUITE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.horvathassociates.com
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
WQ #4
DETAILS
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DATE
APRIL 25, 2012
SCALE
AS NOTED
PROJECT NO.
1121
SHEET NO.
C457
<CONSTRUCTION DRAWINGS>
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PROJECT NO.
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SHEET NO.
C457
<CONSTRUCTION DRAWINGS>

GENERAL NOTES'
A. ALL SCM'S AND ALL ASPECTS APPEARING ON THE CONSTRUCTION DRAWINGSARE
SUBJECT TO AS -BUILT SURVEY AND INSPECTION. ANY ASPECT OF CONSTRUCTION
THAT DOES NOT CONFORM TO PLAN SHALL BE REBUILT OR REPAIREDATTHE
CONTRACTOR'S EXPENSE.
B. IF ANY DISCREPANCIES ARE FOUND BETWEEN THE SPECIFICATIONS AND THE
CONSTRUCTION DRAWINGS, CONTACT THE DESIGN ENGINEER FOR CLARIFICATION
C. ALL ASPECTS OF CONSTRUCTION SHALL CONFORM TO CITY, STATEAND GENERAL
INDUSTRY STANDARDS FOR MATERIALS AND CONSTRUCTION INCLUDING, BUT NOT
LIMITED TO, NORTH CAROLINA BUILDING CODES. CONTRACTOR IS EXPECTEDTO BE
FAMILIAR WITH THESE STANDARDS. IT IS THE RESPONSIBILITY OF THE CONTRACTOR
TO INFORM THE DESIGN ENGINEER IN ANY SITUATION IN WHICH STANDARDS MAY
CONFLICT WITH SPECIFICATIONS AND OR PLANS.
D. PRIOR TO COMMENCING GRADING ACTIVITIES FOR ANY DAM, THE GEOTECHNICAL
ENGINEER SHALL BE RETAINED AND MEET WITH THE ENGINEER. WORK MAY
COMMENCE ON THE DAMS ONLY AFTER NOTICE TO PROCEED FROM THE
ENGINEER.
E. GEOTECHNICAL ENGINEER SHALL OBSERVE ALL ASPECTS OF THE CONSTRUCTION
OF THE DAMS INCLUDING, BUT NOT LIMITED TO, PREPARATION OF THE FOUNDATION,
INSTALLATION OF THE KEY TRENCH, INSTALLATION OFTHE PRINCIPAL SPILLWAY PIPE,
AND THE INSTALLATION OF COMPACTED FILL. THE FREQUENCY OF OBSERVATION
MUST BE SUFFICIENT FOR THE GETOECHNICAL ENGINEER TO STATE, IN HIS OR HER
PROFESSIONAL OPINION, THAT THE SPECIFIC ITEMS OBSERVED AND TESTED WERE
INSTALLED IN ACCORDANCE WITH THE APPROVED CONSTRUCTION DRAWINGS
AND SPECIFICATIONS. GEOTECHNICAL ENGINEER SHALL PROVIDE GEOTECHNICAL
CERTIFICATION IN ACCORDANCE WITH THE LATEST REQUIREMENTS OF THE CITY OF
DURHAM'S BM CERTIFICATION PROGRAM (BCE). ALL ITEMS REQUIRED FOR THE
CERTIFICATION SHALL BE PROVIDED, INCLUDING BUT NOT LIMITEDTO, DAM
EMBANKMENT MATERIAL COMPOSITION AND DENSITY TESTING PAPERWORK
INCLUDING MAP SHOWING LOCATION OF TESTINGS, COPIES OFALL CONCRETE
COMPRESSIVE STRENGTH TESTING PAPERWORK FOR ANY CAST IN PLACE ITEMS
ASSOCIATED WITH THE CONSTRUCTION OF THE DAM, COPY OFTHE PURCHASE
RECEIPT FOR THE PRINCIPAL SPILLWAY PIPE IDENTIFYING THEASTM SPECIFICATIONS
GOVERNING THE MANUFACTURE OF THE PIPE, COPY OFTHE MANUFACTURER'S
CERTIFICATION THAT ANY ARMORING, OTHER THAN CONCRETE, USEDTO ARMOR
THE EMERGENCY SPILLWAY WAS COMPLETED IN ACCORDANCE WITH THE
MANUFACTURER'S PUBLISHED SPECIFICATIONS, COLOR DIGITAL PHOTOGRAPHS
SHOWING THE DAM FOUNDATIONAL AREAS, THE RISER, THE PRINCIPAL SPILLWAY
PIPE AS THOSE ITEMS WERE BEING PREPARED AND INSTALLED.
F. ALL SCM'S WILL BE USED AS SEDIMENT TRAPS DURING CONSTRUCTION. BASINS
SHALL BE CLEANED OF SEDIMENT, AND VEGETATION SHALL BE ESTABLISHED PRIOR
TO FINALIZATION OFTHESCM'S.
G. THE CONTRACTOR SHALL NOTIFY THE ENGINEER IF EXISTING CONDITIONS
ENCOUNTERED IN THE FIELD ARE DIFFERENT FROM CONDITIONS EXPECTED ON THE
PLAN.
H. FINE GRADING OF THE INTERIOR OF THE SCM'S, SOIL AMENDMENT AND FINAL
PLANTING OF WETLAND VEGETATION SHALL NOT BE COMPLETED UNTIL THE SITE IS
FULLY STABILIZED.
AQUATIC SHELF AND DRY POND FLOOR PLANTING NOTES:
A. THE TOP 6- INCHES OF SOIL OF THE AQUATIC SHELF FOR THE WATER QUALITY PONDS,
AND THE ENTIRE FLOOR OF THE DRY POND SHALL INCLUDEAT LEAST 50% MIX OF
TOPSOIL AND /OR ORGANIC MATERIAL.
B. A LETTER SHALL BE PROVIDED BY THE LANDSCAPE COMPANY THAT INSTALLS THE
AQUATIC SHELF PLANTS AND THE DRY POND FLOOR PLANTS CERTIFYING THAT THE
NUMBER, TYPE, AND LOCATION OF ALL PLANTINGS AS INSTALLED IS IN
ACCORDANCE WITH THE CONSTRUCTION DRAWINGS.
SCM OUTLET STRUCTURE NOTES:
A. ANY POURED CONCRETE SHALL BE MINIMUM 3000 PSI (28-DAY STRENGTH) UNLESS
OTHERWISE NOTED.
B. REINFORCED CONCRETE PIPE (RCP) OUTLET BARREL SHALL BE CLASS III RCP (ASTM
C -76). THE PIPE JOINTS SHALL BE CONFINED O -RING RUBBER GASKET JOINTS (ASTM
C -443 8, ASTM C -361).
C. THE MANHOLE OUTLET RISER BASES SHALL BE MONOLITHIC EXTENDED BASE
MANHOLES (AASHTO M -19).
D. CONCRETE FILL LAYER SHALL BE POURED WITHIN THE INTERIOR OF EXTENDED BASE
MANHOLES TO THE DEPTH SPECIFIED ON THE DETAIL.
E. EACH WATER QUALITY POND SHALL BE PROVIDED WITH AN 8 "GATE VALVE AND DIP
PIPE EXTENDING TO THE ELEVATION SHOWN ON THE PROFILES THAT WILL BE USED TO
DRAW DOWN THE PERMANENT POOL OF THE PONDS.
F. ALL OTHER ASPECTS OF THE RISER /BARREL CONSTRUCTION SHALL CONFORM TO THE
DETAILS AND DETAILS NOTES ON THE CONSTRUCTION DRAWINGS.
G.THE BROADCRESTED WEIR EMERGENCY SPILLWAYSSHALL BE CONSTRUCTED
ENTIRELY IN "CUT ".
PIN: 0769 -03 -41 -8938 PIN: 0769 -03-41 -6932 PIN: 0769 -03-41 -4887 PIN: 0769 -0442 -5588 PIN: 0769 -03-44 -6000 PIN: 0769-03 -33 -2232 PIN: 0769-03-24-8486 PIN: 0769 -03-35 -7254 PIN: 0769 -01 -35 -3524 PIN: 0769 -01 -26 -9080 PIN: 0769-01 -06 -9898
Parcel ID: 194413 Parcel ID: 194412 Parcel ID: 194411 Parcel ID: 194383 Parcel ID: 194384 Parcel ID: 193264 Parcel ID: 193265 Parcel ID: 210697 Parcel ID: 193271 Parcel ID: 193270 Parcel ID: 193320
BERM SOIL AND COMPACTION SPECIFICATIONS'
A. CONSTRUCTION OF THE DAMS MUST BE DONE UNDER THE SUPERVISION OF
GEOTECHNICAL ENGINEER THAT IS A REGISTERED PROFESSIONAL ENGINEER IN THE
STATE OF NORTH CAROLINA.
B. ON -SITE GEOTECHNICAL ENGINEER SHALL APPROVE CONTROLLED FILL FOR
PLACEMENT WITHIN THE BERM SECTIONS. THE GEOTECHNICAL ENGINEER SHALL
ALSO SPECIFY THE METHODS THAT WILL BE USED FOR PLACEMENT OF FILL.
GEOTECHNICAL ENGINEER SHALL EITHER CERTIFY THAT SUBGRADE ISSUITABLE FOR
EACH BERM OR SPECIFY PREPARATION METHODS AND MATERIALS.
C. CONTROLLED FILL, AS SPECIFIED BY THE GEOTECHNICAL ENGINEER, IN THE DAM
EMBANKMENTS SHALL BE PLACED IN 6 -INCH LOOSE LIFTS (3 -INCH LOOSE LIFTS
WITHIN 3 -FEET OF EITHER SIDE THE PRINCIPAL SPILLWAY PIPETOA DEPTH OF 2-FEET
OVER THE PIPE) AND SHALL BE COMPACTED TO A DENSITY OF NO LESSTHAT 95% OF
THE STANDARD PROCTOR MAXIMUM DENSITY AT A MOISTURE CONTENT OF +/- 2
PERCENTAGE POINTS OF THE OPTIMUM MOISTURE CONTENT IN ACCORDANCE WITH
ASTM D698. EACH LIFT SHALL BE CONTINUOUS FOR THE ENTIRE LENGTH OF THE
EMBANKMENT. NO BLASTED MATERIALS SHALL BE USED IN THE BERM
CONSTRUCTION. SOILS THAT EXHIBIT SIGNIFICANT SHRINKAGE, SWELLING,
DISPERSIVE CHARACTERISTICS, OR ORGANIC CONTENT GREATER THAN 5% BY
WEIGHT SHALL NOT BE USED.
D. ALL VISIBLE ORGANIC DEBRIS SUCH AS ROOTSAND LIMBSSHALL BE REMOVED
FROM THE FILL MATERIAL PRIOR TO COMPACTION TO THE REQUIRED DENSITY. SOILS
WITH ORGANIC MATTER CONTENT EXCEEDING 5% BY WEIGHT SHALL NOT BE USED.
E. BEFORE PLACEMENT OF CONTROLLED FILL FOR THE BERM SECTIONS, ALL UNSUITABLE
EXISTING MATERIAL SHALL BE REMOVED AND THESURFACES PROPERLY PREPARED
FOR FILL PLACEMENT. STONES LARGER THAN 3 "SHALL BE REMOVED FROM FILL. NO
TREES OR WOODY VEGETATION OF ANY TYPE MAY BE LOCATED IN OR ON THE BERM
SECTIONS.
F. ANY FILL LAYER THAT IS SMOOTH DRUM ROLLED TO REDUCE MOISTURE
PENETRATION DURING A STORM EVENT SHALL BE PROPERLY SCARIFIED PRIOR TO
PLACEMENT OF THE NEXTSOIL LIFT.
G. EARTHWORK COMPACTION WITHIN 3 FEET OF ANY STRUCTURES SHALL BE
ACCOMPLISHED BY MEANS OF HAND TAMPERS, MANUALLY DIRECTED POWER
TAMPERS OR PLATE COMPACTORS OR MINIATURE SELF-PROPELLED ROLLERS. ALL
COMPACTION BY HAND SHALL BE CONDUCTED IN 5" LIFTS. FILLADJACENT TO THE
RISERS AND PRINCIPAL SPILLWAY PIPES SHALL BE PLACEDSO THAT LIFTSARETHE
SAME LEVEL ON BOTH SIDES OF THE STRUCTURES.
H. TESTS FOR PERCENT COMPACTION OF THE PLACED FILL IN THE BERMSSHALL BE
PERFORMED AS QC FOR THE CONSTRUCTION OFTHE DAM. CONTRACTOR SHALL
COORDINATE SO THAT THESE TESTS CAN BE DONE. ALL PORTIONS NOT
CONFORMING TO THE SPECIFIED DEGREE OF COMPACTION SHALL BE REWORKED
OR REBUILT. ALL PORTIONS MUST ACHIEVE SPECIFIED MINIMUM DEGREE OF
COMPACTION. GEOTECHNICAL CERTIFICATION OF SOIL COMPACTION SHALL BE
SUBMITTED WITH FINAL AS -BUILT OF THE WETLANDSYSTEM.
I. A KEY TRENCH SHALL BE PROVIDED IN ALL FILL AREAS OF EACH BERM. DEPTH OF THE
TRENCH SHALL BE BASED ON THE DEPTH RECOMMENDATIONS PROVIDED BYTHE
GEOTECHNICAL ENGINEER AS DETERMINED FROM SOIL BORING LOGS PROVIDED
ALONG THE AXIS OF THE PROPOSED DAM EMBANKMENT.
J. TREATMENT OF SEEPAGE AREAS, SUBGRADE PREPARATION, FOUNDATION
DEWATERING, AND ROCK FOUNDATION PREPARATION MAY BE REQUIREDATTHE
DISCRETION OF THE GEOTECHNICAL ENGINEER. ALL ACTIVITIES SHALL BE CLOSELY
MONITORED AN DOCUMENTED BY THE GEOTECHNICAL ENGINEER.
K. SURFACE WATER AND STREAM FLOW SHALL BE CONTINUOUSLY CONTROLLED
THROUGHOUT CONSTRUCTION AND PLACEMENT OFTHE FILL.
L. FOUNDATION AREAS MAY REQUIRE UNDERCUTTING OF COMPRESSIBLEAND /OR
UNSUITABLE SOILS IN ADDITION TO THAT INDICATED ON THE PLANS. ALLSUCH
UNDERCUTTING SHALL BE PERFORMED AT THE DISCRETION OFTHE GEOTECHNICAL
ENGINEER AND SHALL BE MONITORED AND DOCUMENTED. NO PORTIONSOFTHE
FOUNDATION SOILS MAYBE STABILIZED WITH CRUSHED STONE.
M. NO COMPACTION BY DROP WEIGHTS FROM A CRANE OR HOIST IS ALLOWED.
TEMPORARY GRASS SEEDING SCHEDULE
SEEDING DATE SEEDING MIXTURE APPLICATION RATE
JAN 1 -MAY 1 RYE (GRMN) 120 LBS /AC
MAY 1 -AUG 15 GERMAN MILLET 40 LBS /AC
AUG 15 - DEC 30 RYE (GRMN) 120 LBS /AC
1. SOIL AMENDMENTS: FOLLOW RECOMMENDATIONS OF SOIL TESTS OR APPLY
2,000 LB /AC GROUND AGRICULTURE LIMESTONE AND 750 LBS /AC 10 -10-10
FERTILIZER (FROM AUG 16 - DEC 30, INCREASE 10 -10 -10 TO 1000 LBS /AC).
2. MULCH: APPLY 4000 LB /AC STRAW. ANCHOR STRAW BY TACKING WITH NETTING,
OR A MULCH ANCHORING TOOL. A DISK WITH BLADES SET NEARLY STRAIGHT
CAN BE USED AS A MULCH ANCHORING TOOL,
3. MAINTENANCE:
JAN 1 - AUG 15: REFERTILIZE IF GROWTH IS NOT FULLY ADEQUATE. RESEED,
REFERTILIZE, AND MULCH IMMEDIATELY FOLLOWING EROSION OR OTHER
DAMAGE.
AUG 15 - DEC 30: REPAIR AND REFERTILIZE DAMAGED AREAS IMMEDIATELY. TOP
DRESS WITH 50 LBS /AC OF NITROGEN IN MARCH, IF IT IS NECESSARY TO
EXTEND TEMPORARY COVER BEYOND JUNE 15, OVERSEED WITH 50 LBS /AC
KOBE LESPEDEZA IN LATE FEBRUARY OR EARLY MARCH.
PERMANENT GRASS
SEEDING SCHEDULE
SEEDING DATE SEEDING MIXTURE APPLICATION RATE
AUG 25 - OCT (BEST) TALL FESCUE 200 LBS /AC
FEB - APR 15 {POSSIBLE}
1. ADD 3 -INCH LAYER OF TOPSOIL TO ALL PORTIONS OF THE DAM PRIOR TO
SEEDING. SEED AND MULCH OR HYDROSEED THE AREA AFTER ADDITION OF THE
TOPSOIL.
2, MAINTENANCE: INSPECT AND REPAIR MULCH FREQUENTLY, MOW REGULARLY TO
A HEIGHT OF 46 INCHES.
3. NURSE PLANTS: BETWEEN MAY 1 AND AUG. 15, ADD 15 LB /ACRE SUDANGRASS OR
10 LB /ACRE GERMAN MILLET. BEFORE MAY 1, OR AFTER AUG. 15, ADD 40
LB /ACRE RYE (GRAIN).
SEEDBED PREPARATION
1. CHISEL COMPACTED AREAS AND SPREAD TOPSOIL 3 INCHES DEEP.
2. RIP THE ENTIRE AREA TO 6 INCHES DEPTH.
3. REMOVE ALL LOOSE ROCK, ROOTS, AND OTHER OBSTRUCTIONS LEAVING
SURFACE REASONABLY SMOOTH AND UNIFORM.
4. CONTINUE TILLAGE UNTIL A WELL- PULVERIZED, FIRM REASONABLY UNIFORM
SEEDBED IS PREPARED 4 TO 6 INCHES DEEP.
5. SEED ON A FRESHLY PREPARED SEEDBED AND COVER
6. MULCH IMMEDIATELY AFTER SEEDING AND ANCHOR MULCH.
7. INSPECT ALL SEEDED AREAS AND MAKE NECESSARY REPAIRS OR RESEEDINGS
WITHIN THE PLANTING SEASON, IF POSSIBLE. IF STAND SHOULD BE OVER 60%
DAMAGED, REESTABLISH FOLLOWING ORIGINAL LIME, FERTILIZER AND SEEDING
RATES. SEED LIGHTLY WITH SEEDING EQUIPMENT OR CULTIPACK AFTER SEEDING.
* SEE SEASONAL APPLICATION SCHEDULE
NOTE: ALL POND BERMS AND INTERIOR POND AREAS WILL REQUIRE A HEALTHY
STAND OF GRASS ON A MINIMUM OF 85% OF THE TOTAL AREA AT THE TIME THE
CERTIFICATION PACKAGE IS SUBMITTED TO THE CITY. THE SCM'S WILL NOT
RECEIVE FINAL CERTIFICATION UNTIL THIS REQUIREMENT HAS BEEN MET.
TBM SITE BENCHMARK NCGS MONUMENT
NC F EL = 409.94' NGVD 29
CITY OF DURHAM
PUBLIC WORKS DEPARTMENT
APPROVED
ENGINEERING DATE
STORM WATER DATE
TRANSPORTATION DATE
DATE
DATE
©COPYRIGHT 2012 THIS DOCUMENT AND THE DESIGN ARE THE PROPERTY OF HORVATH ASSOCIATES, P.A. ANY REPRODUCTION WITHOUT PRIOR WRITTEN CONSENT IS PROHIBITED
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HOIRVATH
A S S O C I A T E S
16 CONSULTANT PLACE,SUrrE 201
DURHAM, NORTH CAROLINA 27707
P 919.490.4990 F 919.490.8953
P.O. BOX 970
HARRISON, TENNESSEE 37341
P 423.266.4990
www.h orvat h associates. om
NORTH CAROLINA BOARD OF
EXAMINERS FOR ENGINEERS AND
SURVEYORS LICENSE NO.: C-0676
SCM
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PROJECT NO.
1121
SHEET NO.
C458
<CONSTRUCTION DRAWINGS>
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PROJECT NO.
1121
SHEET NO.
C458
<CONSTRUCTION DRAWINGS>