20140872 Ver 1_Stormwater Info_20140811

STORMWATER MANAGEMENT REPORT
for
INDIAN WELLS SUBDIVISION
Prepared for:
LStar Management
516 N. West Street
Raleigh, NC 2760'
by:
BOHLER
ENGINEERING, NC, PLLC
4011 Westchase Boulevard Suite 290
Raleigh, NC 27607
PHONE [phone]
FAX [phone]
1s1 Submittal May 8, 2014
2nd Submittal July 10, 2014
Bohler Project #: NCR] 42011
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Landon M. Lovelace, PE, NCLID, LEED -AP

Table of Contents
Page
INTRODUCTION............................................................................................. ............................... 1
1.1 PROJECT INFORMATION ................................................................................... ............................... 1
1.2 STORMWATER MANAGEMENT REQUIREMENTS ............................................... ............................... 3
STORMWATER CALCULATIONS ..................................................................... ............................... 4
2.1 METHODOLOGY .......................................................................................... ............................... 4
2.2 CONCLUSIONS ................................................................ ..............................5
2.3 WET POND DESIGN SUMMARY ................................................................... ............................... 7
APPENDICES:
A. DRAINAGE AREA MAPS ............................................................................ ...............................
B. BMP CALCULATIONS ................................................................................. ...............................
C. NUTRIENT LOADING CALCULATIONS ....................................................... ...............................
D. PIPE SIZING, GUTTER SPREAD, & HGL CALCULATIONS ............................. ...............................
E. DISSIPATOR SIZING CALCULATIONS ......................................................... ...............................
F. ENVIRONMENTAL LETTERS AND MAPS ............................. ERROR! BOOKMARK NOT DEFINED.
G. O & M MANUALS ............................. ............................... ERROR! BOOKMARK NOT DEFINED.

SECTION 1
INTRODUCTION
1.1 Project Information
The project site is a total of 34.22 acres, contained currently in seven parcels, located in northwest Cary at the
current terminus of Indian Wells Road. (Refer to Figure 1) The site includes Wake County PIN #'s 0735 -53 -3365
(3.09 Ac), 0735 -53 -1126 (3.04 Ac), 0735 -42 -3994 (11.10 Ac), 0735 -52 -1513 (6.72 Ac), 0735 -53 -1531 (2.50 Ac.),
0735 -52 -3632 (3.30 Ac.), and 0735 -42 -6432 (4.74 Ac). The site is zoned R8 -CU and R40 (currently being re-
zoned to R8 -CU) and is in the Jordan Lake (Upper New Hope) watershed.
The site has been previously developed and currently contains multiple single family dwellings, as well as
numerous out - buildings, sheds, and barns. There are concrete, gravel, and dirt paths throughout the site.
The site is bounded to the east by single family parcels, to the South by a tributary of Panther Creek, on the
west by the Cameron Pond subdivision, and to the north by a tributary to Panther Creek and a single family
parcel. The intent of this project is to create a seventy lot single - family residential subdivision including all
required roadway, utility, and stormwater infrastructure. As a part of this project, the developer is also
required to construct +/- 500 If of Highcroft Drive, a Collector Avenue, per the Comprehensive Transportation
Plan.
The site is a mix of wooded areas and open fields. There are three existing jurisdictional streams (one 50' UTB
and 2 100' UTB), one existing jurisdictional pond (100' UTB), and small pockets of jurisdictional wetlands as
determined by Steven Ball of S &EC and verified by the Town of Cary, and USACE. There is no FEMA mapped
floodplain within the site per FIRM Panel 372200735001, dated May 2, 2006. The topography is rolling with
existing slopes varying from 1% - 20 %. The site generally drains to two existing points of interest. The points of
interest also pick up run -off from large off -site areas and eventually converge southwest of the site before
entering Panther Creek. Please refer to the Drainage Area Map included in Appendix A.
Both of the unnamed streams have an upstream drainage area greater than 50 acres, therefore a flood study
is required for each reach based on Town of Cary requirements. That flood study was prepared by Bohler
Engineering and is submitted under separate cover.
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FIGURE 1: AERIAL VIEW OF SITE
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1.2 Stormwater Management Requirements
This project is subject to the regulations set forth in the Cary Land Development Ordinance, Section 7.3,
pertaining to Stormwater Management. The proposed development will be required to meet all Sections
of the Ordinance, specifically: 7.3.2 Nutrient Reduction Requirements and 7.3.3. Peak Runoff Control. The
purpose of this report is to demonstrate the site's proposed compliance with all stormwater regulations
and to provide supporting documentation to that effect.
Since this site is in the Upper New Hope sub -basin of the Jordan Lake watershed it must meet the target
nutrient loading rates as set forth by NCDWQ. The target rates are 2.2 # /ac /yr for Nitrogen and 0.82
# /ac /yr for Phosphorus. The nutrient loading can be off -set through the use of stormwater best
management practices (BMP's) and /or a payment to the North Carolina Ecosystem Enhancement Program
(NCEEP) or other approved fund. In order to use the buy -down options, the site loading must first be
brought to at least 6 # /ac /yr for Nitrogen through the use of on -site BMP's.
The Stormwater Runoff Control requirements of the Ordinance state that the peak stormwater runoff
leaving the site for the 1 -year, 2 -year, 5 -year, and 10 -year storms shall be no greater for post -
development conditions than pre - development conditions. Calculations were run to identify the peaks
flows for each design storm under the existing conditions, as well as after the proposed build out. On -site
Stormwater BMP's are used to mitigate the increase in run -off associated with the proposed
development.
A large culvert and pedestrian culvert crossing of the stream are required in order to construct Highcroft
Drive and build a pedestrian underpass per the Town's Comprehensive Transportation Plan and Parks and
Greenways Master Plan. A flood study and associated culvert sizing was done for this crossing to ensure
that no negative impacts to surrounding properties result from this development.
Bohler Engineering, NC, PLLC 4011 WestChase Boulevard Suite 290 Raleigh, NC 27607 T: 919 -578 -9000
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SECTION 2
STORMWATER CALCULATIONS
2.1 Methodology
This stormwater study was conducted using the natural drainage features and existing impervious areas
as depicted by an existing field survey provided by M -iii Surveying. Drainage areas were based on field
survey data and proposed development within those drainage areas. The scope of work included the
following analyses:
Hydrology:
Formulation of the 1 -year, 2 -year, 5 -year, 10 -year, and 100 -year hydrographs for the pre - development
and post - development drainage areas were generated with HydroCAD. The Rational Method was used to
develop peak flows for the Type 11, 24 -hour storm events in the Raleigh area. This method requires three
basic parameters: a weighted run -off coefficient (C), Storm Intensity (1), and drainage area in acres (A).
The run -off coefficient values and drainage areas were computed using information taken directly from
the field survey file and Malcolm's Table of Runoff Coefficients. The intensity was determined using the
Intensity Duration Frequency tables (IDF) from the NOAA Atlas 14 rainfall data for Raleigh- Durham
International Airport.
Hydraulics:
Computer simulated reservoir routing of the 1 -year, 2 -year, 5 -year, 10 -year, and 100 -year design storms
utilized stage- storage and stage- discharge functions was completed in HydroCAD. Stage- storage functions
were derived from the proposed grading of the proposed wet ponds. A non - linear regression relation for
surface area versus elevation was derived for each wet pond. This relation estimates the incremental
volume of the basins to the stage or elevation of the basins. Stage- discharge functions were developed to
size the proposed outlet structure for each wet pond. The resulting pre- development and post -
development flows out of the proposed BMP's and at untreated areas are then analyzed to ensure that
there is no increase in flow for all of the required design storms. The HydroCAD modeling results are
provided in Appendix B.
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Nutrient Loading:
Nitrogen and Phosphorus loading and removal calculations for the pre - development and post -
development conditions were run using the Jordan Lake Stormwater Load Accounting Tool (JLSLAT)
developed by NC State University and NCDENR -DWQ. The results of this analysis are further described in
the Conclusions section and the spreadsheet can be found in Appendix C.
Storm Sewer.
Storm sewer design was done using StormCAD software, which uses a variety of methods such as the
Rational Method, Manning's equation, Bernoulli's equation, and FHWA HEC 22 to model inlet capture,
gutter flow, pipe flow, hydraulic grade line, and junction loss. The run -off coefficient values and drainage
areas were computed using information taken directly from the field survey file and Malcolm's Table of
Runoff Coefficients. The intensity was determined using the Intensity Duration Frequency tables (IDF)
from the NOAA Atlas 14 rainfall data for Raleigh- Durham International Airport. Pipe sizing is based on the
10 -year storm and gutter spread is based on a 4" /hour intensity.
Energy Dissipaters:
Riprap aprons were designed per the NCDWQ spreadsheet and the standard nomographs, using the flow
and velocity for the 10 -year storm obtained from the HydroCAD routing and StormCAD results. These
calculations can be found in Appendix E.
2.2 Conclusions
The final BMP designs are based on the Simple Method for the First 1" volume calculation and NCDENR's
BMP Manual take into account the attenuation required to ensure that the site meets the pre -post
requirement for peak flow. Forebays are provided for each pond, with a minimum size of 20% of the
required storage volume. All ponds outlet to a level spreader outside the urban transition buffer (UTB).
Based on the routing study, each proposed detention basin has sufficient volume to safely pass the 100 -
year storm without overtopping the dam. The grading of each wet pond provides sufficient depth and
area at normal pool to meet DWQ surface area requirements. The outlets were designed to discharge the
runoff resulting from the first 1" of rainfall over 2 to 5 days to meet water quality guidelines. There is no
proposed increase in peak runoff, for the site as a whole and at each study point, for any of the design
storms. Refer to Appendix B for BMP sizing calculations.
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Based on the results of the Jordan Lake Stormwater Load Accounting Tool, the post development loading
rates are below the minimum required thresholds to allow for a buy -down of the remaining loading. The
total Nitrogen loading is 3.07 # /ac /yr and the Phosphorus is 0.41 # /ac /yr. A buy -down for Nitrogen only
will be required for this project and is calculated in the Jordan Lake Developer Nutrient Reporting Form
including in Appendix C.
The HGL does not exceed the pipe crowns except in instances where tailwater forces the occurrence; and
in such cases, the proposed pipe is o -ring gasketed. Gutter spread at each inlet is less than the 8' allowed
by Town ordinance. Refer to Appendix D for pipe sizing, gutter spread and hydraulic grade line
calculations.
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2.3 Wet Pond Design Summary
BMP #1- PROPOSED WET POND w/ LEVEL SPREADER
DRAINAGE AREA= 9.620 ACRES
PERCENT IMPERVIOus AREA = 42.2 %
• 1.00" drawdown orifice @ 308.50
• 4' x 4' riser structure w/ trash rack, crest @ 309.50
• 15" RCP Outlet Barrel
• Top of Dam = 313.00
• Emergency Spillway Elevation = 312.00
Storm Event
Peak WSEL
Freeboard (ft)
Qpeak Inflow (cfs)
Qpeak Outflow (cfs)
1 -Year
309.54
3.46
26.06
0.96
2-Year
309.64
3.36
30.62
5.84
5 -Year
309.72
3.28
35.18
10.79
10 -Year
309.77
3.23
39.09
14.56
100 -Year
309.99
3.01
48.86
15.46
BMP ##2- PROPOSED WET POND w/ LEVEL SPREADER
DRAINAGE AREA= 8.60 ACRES
PERCENT IMPERVIOus AREA = 46.5 %
• 1.5" drawdown orifice @ 310.50
• 4' x 4' riser structure w/ trash rack, crest @ 311.50
• 15" RCP Outlet Barrel
• Top of Dam = 313.00
• Emergency Spillway Elevation = 312.25
Storm Event
Peak WSEL
Freeboard (ft)
Qpeak Inflow (cfs)
Qpeak Outflow (cfs)
1 -Year
311.04
1.96
24.50
0.04
2-Year
311.12
1.88
28.79
0.04
5 -Year
311.21
1.79
33.08
0.05
10 -Year
311.28
1.72
36.75
0.05
100 -Year
311.46
1.53
45.94
0.06
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BMP #3- PROPOSED WET POND w/ LEVEL SPREADER
DRAINAGE AREA= 2.640 ACRES
PERCENT IMPERVIOus AREA = 48.5 %
• 0.7" drawdown orifice @ 321.50
• 4' x 4' riser structure w/ trash rack, crest @ 322.50
• 15" RCP Outlet Barrel
• Top of Dam = 324.00
• Emergency Spillway Elevation = 323.00
Storm Event
Peak WSEL
Freeboard (ft)
Qpeak Inflow (cfs)
Qpeak Outflow (cfs)
1 -Year
322.20
1.80
7.89
0.01
2-Year
322.30
1.70
9.27
0.01
5 -Year
322.40
1.60
10.65
0.01
10 -Year
322.48
1.52
11.84
0.01
100 -Year
322.61
1.39
14.80
3.72
Refer to Appendix B for full BMP sizing and routing calculations.
Bohler Engineering, NC, PLLC 4011 WestChase Boulevard Suite 290 Raleigh, NC 27607 T: 919 -578 -9000
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APPENDIX A
DRAINAGE AREA MAPS

APPENDIX B
BMP CALCULATIONS

Project Name: Indian Wells
Cit State: Cary, NC
BMP Sizing Worksheet: BMP #1- Wet Pond
Project #: NCR142011
Date: 7/11/2014
Surface Area to Drainage Area Ratio for Permanent Pool Sizing for85% Pollutant Removal Efficiency in the Piedmont
%Impervious
Cover
Permanent Pool Depth (feet)
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
10
0.59
0.54
0.49
0.46
0.43
0.39
0.35
0.33
0.31
0.30
0.29
0.40
0.26
20
0.97
0.88
0.79
0.75
0.70
0.65
0.59
0.55
0.51
0.49
0.46
0.70
0.44
30
1.34
1.21
1.08
1.03
0.97
0.90
0.83
0.77
0.70
0.67
0.64
0.90
0.62
40
1.73
1.58
1.43
1.34
1.25
1.15
1.05
0.98
0.90
0.86
0.82
1.20
0.77
50
2.06
1.90
1.73
1.62
1.50
1.40
1.30
1.20
1.09
1.05
1.00
1.50
0.92
60
2.40
2.22
2.03
1.87
1.71
1.61
1.51
1.40
1.29
1.24
1.18
1.80
1.10
70
2.88
2.64
2.40
2.24
1 2.07
1.93
1.79
1 1.67
1 1.54
1 1.45
1 75
2.00
1.26
80
3.36
3.07
2.78
2.58
2.38
2.24
2.10
1.98
1.86
1.73
1.60
2.10
1.42
90
3.74
3.42
3.10
2.88
2.66
2.50
2.34
2.23
2.11
1.97
1.83
2.50
1.67
Source: NCUENN /UWQStormwaterBMV Manual, lable 11-1
STORMWATER BMP 1 - WET POND (25% TN Removal)
Land Use
Area
(ac)
%IA
Imp. Area
(ac)
Roadway & Sidewalk
1.52
100
1.5
Lots (4000sf /lot)
2.54
100
2.5
Pervious Area
5.56
0
0.0
Totals
9.62
4.1
Total %Impervious Surface Area = 42.2 %
Surface Area of Permanent Pool:
Assumed depth = 4.5 feet
SA /DA ratio = 1.40 % From Table From Table 1.1
Minimum pond surface area (SA) _ (DA * SA /DA ratio) /100
SA= 0.135 acres
5867 sq.ft.
Normal pool elevation = 308.5 feet
Surface area provided= 6032 sq. ft.
0.138 AC
1 -Inch Runoff Volume Calculation
Using the runoff volume calculations in the "Simple Method" as described by Schueler (1987)
Rv = 0.05 + 0.009(1) where, Rv = Runoff coefficient, in. /in.
I = Percent impervious
Rv= 0.43 in. /in.
Total runoff volume from 1 -inch precipitation:
Runoff volume, S = (Design rainfall) (Rv) (Drainage Area)
S= 0.345 acre -ft
15010 cu. ft.
Water quality pool elevation= 310.50 feet
Storage volume provided= 0.379 acre -ft
16502 cu. ft.

BMP 1 DRAWDOWN CALCULATIONS
308.5 = Permanent Pool Elevation and
Orifice Invert Elevation (ft)
6032 = Permanent Pool Area (ft)
310.5 = Water Quality Pool Elev. (ft)
9555 = Water Quality Pool Area (ft)
0.6 = Cd, Orifice Coefficient
1.5 = Orifice Diameter (in)
48 = Drawdown Time (hours)
3.5.2.1 Drawdown Time Calculations for a Pond with an Orifice Outlet
In the above Figure_
.31 = Area of pond at the beginning of drawdown
A, = Area of pond at the end of drawdoun
R — Area Area of pond at time_ t during drawdovm
An = Area of pond at the orifice outlet elevation
T= Time for water level to fall from H1 to H2
A = Resen oir Area
Cd = Orifice coefficient of discbarge
a = Orifice area
g = Acceleration of gravity
Hi = Maximum head (t=0)
H: = Head when t = T (H: = 0 )
For the specific case where A. = A0 and Hz = 0
T # 1 2 *. * 1 -3 +"' A, 40 Ism 3 ,3 I Cd *A* 2 *g + 0 ! 3. Hi 1
Cd�a* 4L *g 3 3

Project Name: Indian Wells
City/State: Cary, NC
BMP Sizing Worksheet: BMP #2 - Wet Pond
Project #: NCR142011
Date: 7/11/2014
Surface Area to Drainage Area Ratio for Permanent Pool Sizing for 85% Pollutant Removal Efficiency in the Piedmont
% Impervious
Cover
Permanent Pool Depth (feet)
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
900
10
0.59
0.54
0.49
0.46
0.43
0.39
0.35
0.33
0.31
0.30
0.29
0.40
0.26
20
0.97
0.88
0.79
0.75
0.70
0.65
0.59
0.55
0.51
0.49
0.46
0.70
0.44
30
1.34
1.21
1.08
1.03
0.97
0.90
0.83
0.77
0.70
0.67
0.64
0.90
0.62
40
1.73
1.58
1.43
1.34
1.25
1.15
1.05
0.98
0.90
0.86
0.82
1.20
0.77
50
2.06
1.90
1.73
1.62
1.50
1.40
1.30
1.20
1.09
1.05
1.00
1.50
0.92
60
2.40
2.22
2.03
1.87
1.71
1.61
1.51
1.40
1.29
1.24
1.18
1.80
1 1.10
70
2.88
2.64
2.40
2.24
2.07
1.93
1.79
1.67
1.54
1.45
1.35
2.00
1.26
80
3.36
3.07
2.78
2.58
2.38
2.24
2.10
1.98
1.86
1.73
1.60
2.10
1.42
90
3.74
3.42
3.10
2.88
2.66
2.50
2.34
2.23
2.11
1.97
1.83
2.50
1.67
Source: NCDENR /DWQStormwater BMP Manual, Table 10 -1
STORMWATER BMP 2 - WET POND (25% TN Removal)
Land Use
Area
(ac)
% IA
Imp. Area
(ac)
Roadway & Sidewalk
1.37
100
1.4
Lots(4000sf /lot)
2.63
100
2.6
Pervious Area
4.60
0
0.0
Totals
1 8.60
4.0
Total % Impervious Surface Area = 46.5 %
Surface Area of Permanent Pool:
Assumed depth = 4.5 feet
SA /DA ratio = 1.52 % From Table 1.1
Minimum pond surface area (SA) _ (DA * SA /DA ratio) /100
SA= 0.131 acres
5694 sq.ft.
Normal pool elevation = 310.5 feet
Surface area provided = 12458 sq. ft.
0.286 Ac
1 -Inch Runoff Volume Calculation
Using the runoff volume calculations in the "Simple Method" as described by Schueler (1987)
Rv= 0.05 +0.009(1) where, Rv = Runoff coefficient, in./in.
I = Percent impervious
Rv= 0.47 in. /in.
Total runoff volume from 1 -inch precipitation:
Runoff volume, S = (Design rainfall) (Rv) (Drainage Area)
S = 0.336 acre -ft
14629 cu. ft.
Water quality pool elevation= 311.50 feet
Storage volume provided = 0.341 acre -ft
14866 cu. ft.

BMP 2 DRAWDOWN CALCULATIONS
310.5 = Permanent Pool Elevation and
Orifice Invert Elevation (ft)
12458 = Permanent Pool Area (ft)
311.5 = Water Quality Pool Elev. (ft)
16270 = Water Quality Pool Area (ft)
0.6 = Cd, Orifice Coefficient
1.5 = Orifice Diameter (in)
65 = Drawdown Time (hours)
3.5.2.1 Drawdown Time Calculations for a Pond with an Orifice Outlet
In the above Figure_
.31 = Area of pond at the beginning of drawdown
A, = Area of pond at the end of drawdoun
R — Area Area of pond at time_ t during drawdovm
An = Area of pond at the orifice outlet elevation
T= Time for water level to fall from H1 to H2
A = Resen oir Area
Cd = Orifice coefficient of discbarge
a = Orifice area
g = Acceleration of gravity
Hi = Maximum head (t=0)
H: = Head when t = T (H: = 0 )
For the specific case where A. = A0 and Hz = 0
T # 1 2 *. * 1 -3 +"' A, 40 Ism 3 ,3 I Cd *A* 2 *g + 0 ! 3. Hi 1
Cd�a* 4L *g 3 3

Project Name: Indian Wells
City/State: Cary, NC
BMP Sizing Worksheet: BMP #2 - Wet Pond
Project #: NCR142011
Date: 7/11/2014
Surface Area to Drainage Area Ratio for Permanent Pool Sizing for 85% Pollutant Removal Efficiency in the Piedmont
% Impervious
Cover
Permanent Pool Depth (feet)
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
10
0.59
0.54
0.49
0.46
0.43
0.39
0.35
0.33
0.31
0.30
0.29
0.40
0.26
20
0.97
0.88
0.79
0.75
0.70
0.65
0.59
0.55
0.51
0.49
0.46
0.70
0.44
30
1.34
1.21
1.08
1.03
0.97
0.90
0.83
0.77
0.70
0.67
0.64
0.90
0.62
40
1.73
1.58
1.43
1.34
1.25
1.15
1.05
0.98
0.90
0.86
0.82
1.20
0.77
50
2.06
1.90
1.73
1.62
1.50
1.40
1.30
1.20
1.09
1.05
1.00
1.50
0.92
60
2.40
2.22
2.03
1.87
1.71
1.61
1.51
1.40
1.29
1.24
1.18
1.80
1.10
70
2.88
2.64
2.40
2.24
2.07
1.93
1.79
1.67
1.54
1.45
1.35
2.00
1.26
80
3.36
3.07
2.78
2.58
2.38
2.24
2.10
1.98
1.86
1.73
1.60
2.10
1.42
90
3.74
3.42
3.10
2.88
2.66
2.50
2.34
2.23
2.11
1.97
1.83
2.50
1.67
Source: NCDENR /DWQStormwater BMP Manual, Table 10 -1
STORMWATER BMP 3 - WET POND (25% TN Removal)
Land Use
Area
(ac)
% IA
Imp. Area
(ac)
Roadway & Sidewalk
0.90
100
0.9
Lots (4000sf /lot)
0.38
100
0.4
Pervious Area
1.36
0
0.0
Totals
1 2.64
1.3
Total % Impervious Surface Area = 48.5 %
Surface Area of Permanent Pool:
Assumed depth = 4.5 feet
SA /DA ratio = 1.58 % From Table 1.1
Minimum pond surface area (SA) _ (DA * SA /DA ratio) /100
SA= 0.042 acres
1817 sq. ft.
Normal pool elevation = 321.5 feet
Surface area provided = 2429 sq. ft.
0.056 Ac
1 -Inch Runoff Volume Calculation
Using the runoff volume calculations in the "Simple Method" as described by Schueler (1987)
Rv= 0.05 +0.009(1) where, Rv = Runoff coefficient, in./in.
I = Percent impervious
Rv= 0.49 in. /in.
Total runoff volume from 1 -inch precipitation:
Runoff volume, S = (Design rainfall) (Rv) (Drainage Area)
S = 0.107 acre -ft
4661 cu. ft.
Water quality pool elevation= 322.85 feet
Storage volume provided = 0.120 acre -ft
5247 cu.ft.

BMP 3 DRAWDOWN CALCULATIONS
321.5 = Permanent Pool Elevation and
Orifice Invert Elevation (ft)
2429 = Permanent Pool Area (ft)
322.5 = Water Quality Pool Elev. (ft)
4309 = Water Quality Pool Area (ft)
0.6 = Cd, Orifice Coefficient
0.75 = Orifice Diameter (in)
57 = Drawdown Time (hours)
3.5.2.1 Drawdown Time Calculations for a Pond with an Orifice Outlet
In the above Figure_
.31 = Area of pond at the beginning of drawdown
A, = Area of pond at the end of drawdoun
R — Area Area of pond at time_ t during drawdovm
An = Area of pond at the orifice outlet elevation
T= Time for water level to fall from H1 to H2
A = Resen oir Area
Cd = Orifice coefficient of discbarge
a = Orifice area
g = Acceleration of gravity
Hi = Maximum head (t=0)
H: = Head when t = T (H: = 0 )
For the specific case where A. = A0 and Hz = 0
T # 1 2 *. * 1 -3 +"' A, 40 Ism 3 ,3 I Cd *A* 2 *g + 0 ! 3. Hi 1
Cd�a* 4L *g 3 3

A 3 -BMP
q___` C3-POST
BMP #3 DA #3 -POST
A 1-BMP
1 -POST
BMP #1 DA #1 -POST
2 -POST
A DA #2 -POST
2 -BMP
BMP #2
Subcat Reach on Link Routing Diagram for Pond Routing
Prepared by Bohler Engineering, Printed 7/7/2014
FHyd,.CAD@ 10.00 s/n 07811 © 2013 Hydro CAD Software Solutions LLC

Pond Routing
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area C Description
(acres) (s u bcatch me nt-n u mbe rs)
5.170
0.90
Lots (1 -POST, 2 -POST)
6.830
0.35
Pervious (1 -POST, 3 -POST)
4.600
0.35
Pervious (2 -POST)
2.890
0.90
Roads & Sidewalk (1 -POST, 2 -POST)
1.370
0.90
Roads & Sidewalk & Lots (3 -POST)
20.860
0.60
TOTAL AREA

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 1 -POST: DA #1 -POST
Runoff = 26.06 cfs @ 0.08 hrs, Volume= 0.186 af, Depth= 0.23"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
1.520 0.90 Roads & Sidewalk
2.540 0.90 Lots
5.560 0.35 Pervious
9.620 0.58 Weighted Average
9.620 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 1 -POST: DA #1 -POST
Hydrograph
26.06 cfs
- --
25 j - IDF _Rafleigh =N U_1 =yr
DurAtion*5 niin,
-; - - -- - , -- - ----- ----- ----- ,rin�ern =4.80 iri Thr -
20-
Runoff Area = 9.620 ac
j Rupoff Volu e= 18 of
o Runoff Depth =0.' T'
-r- ----r----T----T----
10- Tc =5.0 min
C =0.58
5-
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 2 -POST: DA #2 -POST
Runoff = 24.50 cfs @ 0.08 hrs, Volume= 0.175 af, Depth= 0.24"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk
2.630 0.90 Lots
4.600 0.35 Pervious
8.600 0.61 Weighted Average
8.600 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 2 -POST: DA #2 -POST
Hydrograph
24.50 cfs - - -! - - -! - -- -------------------- r - - - -! ------ -Y - - --
IDF- R9leigh -NCISU 1 -yr
- -- - - -- Duration'-5 min, -
20 Inten =4.80 in /hr
N -! -- !-
------------ - - - - -- Runoff - rea =8.604ac-
15- Rupoff Volume =0.17$ of
3 I I I I I
o - - - + -- -- - - - - -I_ Runoff Peptti=o.�4 "-
u_ 10.
Tc=5.0 min
C =0.61
5
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 3 -POST: DA #3 -POST
Runoff = 7.89 cfs @ 0.08 hrs, Volume= 0.056 af, Depth= 0.26"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk & Lots
1.270 0.35 Pervious
2.640 0.64 Weighted Average
2.640 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 3 -POST: DA #3 -POST
Hydrograph
7.89 cfs ---- +--------- +----------- - - - - -- - - -- -
tbi
IDF- Raleigh -NCSU 1 -yr
- - - - - - - ----- --I -- - - -I- - --
7 Duration =5 rein,
------------------------------ ---------- Anten =4.80- i -r /hr-
6 Runoff Alrea =2.640 ac
5 Runoff Volume "0.056 of
3 - - -- ---- r----r----+----- ---------- --- R4noff l,Depth= 0:26'-
4
0 .
IL _Tc =5.0 min_
3= C =0.64
----+----+ ---- r ---- + ---- +----+----+ ---- + -----
----------i----
2
+ - - - - + - - - - + - - - - + - --- + - - - - + - - - - + - - - - + -----
- - - -I- - - - -I- - - -
1
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Q Runoff

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 6
Summary for Pond 1 -BMP: BMP #1
Inflow Area =
9.620 ac, 0.00% Impervious, Inflow Depth = 0.23" for 1 -yr event
Inflow =
26.06 cfs @
0.08 hrs, Volume= 0.186 of
Outflow =
0.96 cfs @
0.17 hrs, Volume= 0.056 af, Atten= 96 %, Lag= 5.0 min
Primary =
0.96 cfs @
0.17 hrs, Volume= 0.056 of
Secondary =
0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind
method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 309.54' @ 0.17 hrs
Surf.Area= 8,450 sf Storage= 8,012 cf
Plug -Flow detention time= 596.3
min calculated for 0.056 of (30% of inflow)
Center -of -Mass det. time= 594.2
min ( 599.3 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 308.50' 44,258 cf Custom Stage Data (Prismatic)Listed below
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
308.50
6,032
0 0
309.00
7,838
3,468 3,468
310.00
8,969
8,404 11,871
310.50
9,555
4,631 16,502
311.00
10,156
4,928 21,430
312.00
11,400
10,778 32,208
313.00
12,700
12,050 44,258
Device Routing
Invert
Outlet Devices
#1 Primary
304.00'
15.0" Round Culvert
L= 48.4' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 304.00'/ 303.00' S=0.0207'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1
309.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1
308.50'
1.0" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.90 cfs @ 0.17 hrs HW= 309.54' (Free Discharge)
t = Culvert (Passes 0.90 cfs of 14.84 cfs potential flow)
2 =Weir Opening (Weir Controls 0.87 cfs @ 0.66 fps)
3 Orifice /Grate (Orifice Controls 0.03 cfs @ 4.81 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 308.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 7
'• • •,
Hydrograph
• 1 • cfs
Peak Etev=309.54
Storage=-9,012 cf
LL 10
offI
�I
it
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
313
G&VA
a�
T
0 311
0
a 310
w
Pond 1 -BMP: BMP #1
Stage- Area - Storage
Surracp1w-
0 2,000 4,000
E Inflow
[ Outflow
❑ Primary
❑ Secondary
etted Area (sq -ft)
6,000 8,000 10,000 12,000
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 8
Summary for Pond 2 -BMP: BMP #2
Inflow Area = 8.600 ac, 0.00% Impervious, Inflow Depth = 0.24" for 1 -yr event
Inflow = 24.50 cfs @
0.08 hrs, Volume= 0.175 of
Outflow = 0.04 cfs @
0.17 hrs, Volume= 0.071 af, Atten= 100 %, Lag= 5.2 min
Primary = 0.04 cfs @
0.17 hrs, Volume= 0.071 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 311.04' @ 0.17 hrs
Surf.Area= 15,439 sf Storage= 7,591 cf
Plug -Flow detention time= 683.5
min calculated for 0.071 of (40% of inflow)
Center -of -Mass det. time= 681.5
min ( 686.5 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 310.50' 41,357 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
310.50 12,459
0 0
311.00 15,367
6,957 6,957
311.50 16,270
7,909 14,866
312.00 17,188
8,365 23,230
313.00 19,065
18,127 41,357
Device Routing Invert
Outlet Devices
#1 Primary 306.00'
15.0" Round Culvert
L= 43.0' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 306.00'/ 305.00' S=0.0233'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 311.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 310.50'
1.5" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.25'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.04 cfs @ 0.17 hrs HW= 311.04' (Free Discharge)
t = Culvert (Passes 0.04 cfs of 14.52 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.04 cfs @ 3.33 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 310.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 9
Pond 2 -BMP: BMP #2
Hydrograph
24.50 cfs
Inflow Area= 8.600'ac
25 -- L - - - -' i --- - ' - - -- ----- Peak EI'p-v =30LI.04'
Storage= 7�1,591�1 cf
20 -- ------- -I - - -- -------- - - - - +- - - - - -' - - -- - --
I I I I I I I I I I I
15 - - - -- - - -- - - --
3 I I I I I I I I I I I
10 -L----'--------1------------1--------'L---i---J---
0.00 cfs
31
a�
T
31
C
0
a�
w
31
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 2 -BMP: BMP #2
Stage- Area - Storage
Q „mace /Horizor +' sd Area (sq -ft)
0 5,000 10,000 15,000
E Inflow
[ Outflow
❑ Primary
❑ Secondary
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 10
Summary for Pond 3 -BMP: BMP #3
Inflow Area =
2.640 ac, 0.00% Impervious, Inflow Depth = 0.26" for 1 -yr event
Inflow =
7.89 cfs @
0.08 hrs, Volume= 0.056 of
Outflow =
0.01 cfs @
0.17 hrs, Volume= 0.019 af, Atten= 100 %, Lag= 5.2 min
Primary =
0.01 cfs @
0.17 hrs, Volume= 0.019 of
Secondary =
0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind
method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 322.20'
@ 0.17 hrs
Surf.Area= 4,122 sf Storage= 2,445 cf
Plug -Flow detention time= 698.4
min calculated for 0.019 of (34% of inflow)
Center -of -Mass det.
time= 696.5
min ( 701.5 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 321.50' 11,048 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
321.50
2,429
0 0
322.00
3,980
1,602 1,602
322.85
4,596
3,645 5,247
323.00
4,709
698 5,945
324.00
5,498
5,104 11,048
Device Routing
Invert
Outlet Devices
#1 Primary
317.00'
15.0" Round Culvert
L= 32.2' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 317.00'/ 316.50' S=0.0155'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1
322.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1
321.50'
0.7" Vert. Orifice /Grate C= 0.600
#4 Secondary 323.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.01 cfs @ 0.17 hrs HW= 322.20' (Free Discharge)
t = Culvert (Passes 0.01 cfs of 14.87 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.01 cfs @ 3.93 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 321.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 11
32
a�
T
32
C
0
a�
w
32
ir
r' •
--Storage--2,445
0 24
Time (hours)
Pond 3 -BMP: BMP #3
Stage- Area - Storage
Surface /H ^ri-7nn +n1AP sd Area (sq -ft)
0 1,000 2,000 3,000 4,000 5,000
E Inflow
Outflow
❑ Primary
❑ Secondary
0 5,000 10,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 12
Summary for Subcatchment 1 -POST: DA #1 -POST
Runoff = 30.62 cfs @ 0.08 hrs, Volume= 0.218 af, Depth= 0.27"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
1.520 0.90 Roads & Sidewalk
2.540 0.90 Lots
5.560 0.35 Pervious
9.620 0.58 Weighted Average
9.620 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 1 -POST: DA #1 -POST
Hydrograph
30.62 cfs
30- OF- Raleigh -NCISU 2 -yr
- 1---- 1--- -i - - -- Duration'-5 min, -
25 Inten =5.64 in /hr
-- - - - - -- - - -- AL noff Area=9-620r ac-
,� 20.
Rupoff !Volu'lne =0.21$ of
o 15 - - -- - - -- Runoff Oeptfi =0.�T'
- - -- -- --------- - - - - -- - -- Tc-=5.0 -min-
10 C =0.58
5-
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 13
Summary for Subcatchment 2 -POST: DA #2 -POST
Runoff = 28.79 cfs @ 0.08 hrs, Volume= 0.205 af, Depth= 0.29"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk
2.630 0.90 Lots
4.600 0.35 Pervious
8.600 0.61 Weighted Average
8.600 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 2 -POST: DA #2 -POST
Hydrograph
28.79 cfs - -- -- - - - - -' - -- - - -- - - -- - - --
IDF- Raleigh -NCISU 2 -yr
25
-T - - -- - - -- - -- Durations =5 niin,-
Inten =5.64 in /hr
N 20- Runoff Area = 8.600 ac
-!, -- -!, -- - - - -- -- I ----- 1-Rupoff VoIuMe =0.20 af-
0 15 Runoff Oeptfi =0.�9„
- - - -- -- - - - -- Tc=5.0 -min-
10-
C =0.61
5
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment 3 -POST: DA #3 -POST
Runoff = 9.27 cfs @ 0.08 hrs, Volume= 0.066 af, Depth= 0.30"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk & Lots
1.270 0.35 Pervious
2.640 0.64 Weighted Average
2.640 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 3 -POST: DA #3 -POST
Hydrograph
9.27 cfs - - -- i - - -- I ---- �----- �----- �----- �---- -� - - -- i - - -- i - - -- i - - --
g-
OF- Raleigh -NCISU 2 -yr
I I
- - -- - - -- - - -- - - -- ------------------ - -rDur Lion =5 -Min--
8
- - -- - - -- - - -- - - - -- - - - - - I-
, -
7. -- - - -- ------------------- 1nfen 664- irthr-
,� I I I I I gI unof -ATI ea= I f40ac-
6. I I
- --- -; - - -- ------------ Rupoff VoFuMe =�.06$ -af-
0 5 --- - - - - -! - - -! ----- 'u�i�off Dept =a.0 "-
FL 4. I I I I I I I I I I I
- - - -, - - -- - - - - -------------- - I - - - - - - - Tc=5.0 -min-
3 - -- - - -- - - -- - - -- --------------- - - - - -' ---------1C=O.-64-
2
0- .
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Q Runoff

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 15
Summary for Pond 1 -BMP: BMP #1
Inflow Area =
9.620 ac, 0.00% Impervious, Inflow Depth = 0.27" for 2 -yr event
Inflow =
30.62 cfs @
0.08 hrs, Volume= 0.218 of
Outflow =
5.84 cfs @
0.15 hrs, Volume= 0.088 af, Atten= 81 %, Lag= 4.2 min
Primary =
5.84 cfs @
0.15 hrs, Volume= 0.088 of
Secondary =
0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind
method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 309.64' @ 0.15 hrs
Surf.Area= 8,564 sf Storage= 8,861 cf
Plug -Flow detention time= 381.0
min calculated for 0.088 of (40% of inflow)
Center -of -Mass det. time= 379.4
min ( 384.4 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 308.50' 44,258 cf Custom Stage Data (Prismatic)Listed below
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
308.50
6,032
0 0
309.00
7,838
3,468 3,468
310.00
8,969
8,404 11,871
310.50
9,555
4,631 16,502
311.00
10,156
4,928 21,430
312.00
11,400
10,778 32,208
313.00
12,700
12,050 44,258
Device Routing
Invert
Outlet Devices
#1 Primary
304.00'
15.0" Round Culvert
L= 48.4' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 304.00'/ 303.00' S=0.0207'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1
309.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1
308.50'
1.0" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =5.71 cfs @ 0.15 hrs HW= 309.64' (Free Discharge)
t = Culvert (Passes 5.71 cfs of 14.98 cfs potential flow)
2 =Weir Opening (Weir Controls 5.68 cfs @ 1.23 fps)
3 Orifice /Grate (Orifice Controls 0.03 cfs @ 5.05 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 308.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 16
'• • •,
Hydrograph
30.62
30- 1 .• • :.
5.84 cfs
I
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
313
G&VA
a�
T
0 311
0
a 310
w
Pond 1 -BMP: BMP #1
Stage- Area - Storage
Surracp1w-
0 2,000 4,000
Inflow
Outflow
❑ Primary
❑ Secondary
etted Area (sq -ft)
6,000 8,000 10,000 12,000
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 17
Summary for Pond 2 -BMP: BMP #2
Inflow Area = 8.600 ac, 0.00% Impervious, Inflow Depth = 0.29" for 2 -yr event
Inflow = 28.79 cfs @
0.08 hrs, Volume= 0.205 of
Outflow = 0.04 cfs @
0.17 hrs, Volume= 0.078 af, Atten= 100 %, Lag= 5.2 min
Primary = 0.04 cfs @
0.17 hrs, Volume= 0.078 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 311.12' @ 0.17 hrs
Surf.Area= 15,591 sf Storage= 8,920 cf
Plug -Flow detention time= 688.8
min calculated for 0.078 of (38% of inflow)
Center -of -Mass det. time= 686.7
min ( 691.7 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 310.50' 41,357 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
310.50 12,459
0 0
311.00 15,367
6,957 6,957
311.50 16,270
7,909 14,866
312.00 17,188
8,365 23,230
313.00 19,065
18,127 41,357
Device Routing Invert
Outlet Devices
#1 Primary 306.00'
15.0" Round Culvert
L= 43.0' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 306.00'/ 305.00' S=0.0233'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 311.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 310.50'
1.5" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.25'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.04 cfs @ 0.17 hrs HW= 311.12' (Free Discharge)
t = Culvert (Passes 0.04 cfs of 14.65 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.04 cfs @ 3.61 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 310.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 18
inflow .11
Peak E1ev=3M'2'
•.• -:•, cf
ff@Ylnl ME
zz
I
�I
it
31
a�
T
31
C
0
a�
w
31
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 2 -BMP: BMP #2
Stage- Area - Storage
Q „mace /Horizor +' sd Area (sq -ft)
0 5,000 10,000 15,000
E Inflow
[ Outflow
❑ Primary
❑ Secondary
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 19
Summary for Pond 3 -BMP: BMP #3
Inflow Area =
2.640 ac, 0.00% Impervious, Inflow Depth = 0.30" for 2 -yr event
Inflow =
9.27 cfs @
0.08 hrs, Volume= 0.066 of
Outflow =
0.01 cfs @
0.17 hrs, Volume= 0.021 af, Atten= 100 %, Lag= 5.2 min
Primary =
0.01 cfs @
0.17 hrs, Volume= 0.021 of
Secondary =
0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind
method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 322.30'
@ 0.17 hrs
Surf.Area= 4,195 sf Storage= 2,874 cf
Plug -Flow detention time= 700.3
min calculated for 0.021 of (31 % of inflow)
Center -of -Mass det.
time= 698.0
min ( 703.0 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 321.50' 11,048 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
321.50
2,429
0 0
322.00
3,980
1,602 1,602
322.85
4,596
3,645 5,247
323.00
4,709
698 5,945
324.00
5,498
5,104 11,048
Device Routing
Invert
Outlet Devices
#1 Primary
317.00'
15.0" Round Culvert
L= 32.2' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 317.00'/ 316.50' S=0.0155'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1
322.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1
321.50'
0.7" Vert. Orifice /Grate C= 0.600
#4 Secondary 323.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.01 cfs @ 0.17 hrs HW= 322.30' (Free Discharge)
t = Culvert (Passes 0.01 cfs of 15.03 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.01 cfs @ 4.22 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 321.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 20
10
rA
6
3 5
0
a: 4
Pond 3 -BMP: BMP #3
Hydrograph
9.27 CfS - -- III - -- - -- - - -- III - -- - -- - - -- III--- -11 - -- - - - - --
- -- - -- --------- - Inflow Area =2.640'ac
peak �IIev =322 M
- - - -Storage =2,$74 cf
I I I I I I I I I I I
I I I I I I I I I I I
------- -I - - -- t ------- -I - - -- t --- -I - - -- r - -- - - -- 1 - --
I I I I I I I I I I I I
I I
I I I I I I I I I I I
T---- - - - -I_ - -- Y---- - - - -I_ - -- Y--- -I - - -- Y - -- T - -- Y - --
I I I I I I I I I I I
-..
I I I I I I I I I I
0.00 CfS
32
a�
T
32
C
0
a�
w
32
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 3 -BMP: BMP #3
Stage- Area - Storage
Surface /H ^ri-7nn +n1AP sd Area (sq -ft)
0 1,000 2,000 3,000 4,000
5,000
E Inflow
Outflow
❑ Primary
❑ Secondary
0 5,000 10,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 21
Summary for Subcatchment 1 -POST: DA #1 -POST
Runoff = 35.18 cfs @ 0.08 hrs, Volume= 0.251 af, Depth= 0.31"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
1.520 0.90 Roads & Sidewalk
2.540 0.90 Lots
5.560 0.35 Pervious
9.620 0.58 Weighted Average
9.620 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 1 -POST: DA #1 -POST
Hydrograph
35.18 cfs
7 - - - - T ---
-
35- OF- Raleigh -NCISU 5 -yr
- -- - - -- - - -- - - -- --------------------,DurAtion=5Min;-
30
-
----- - - - - - - - - - -
lnfgn =6A8_1h1hr_
N 25- Runoff Area = 9.620 ac
---- -; - - -- - - - -- -Ru' off 'Vofu + -e_j. - -
= 25 af-
20-
o--- - - - - -- - - -- Runoff Oept� =0 1 "-
Tc =5.0 min
---t----I----I----7---------------r----r----r---------7----
10- C =0.58
5"
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 22
Summary for Subcatchment 2 -POST: DA #2 -POST
Runoff = 33.08 cfs @ 0.08 hrs, Volume= 0.236 af, Depth= 0.33"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk
2.630 0.90 Lots
4.600 0.35 Pervious
8.600 0.61 Weighted Average
8.600 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 2 -POST: DA #2 -POST
Hydrograph
33.08 cfs - - - -- -- -'I - - - - -- - - - - T - - - - - - - - T - - --
- IDF- R9I_eiah- NCISU_5 -yr_
30 DurAtion*5 niin,
- - -- ; -- - - - -- -1nt n =6 46- ifithr-
25-
Runoff Area = 8.600' ac
� -
r----r----r----r-----i----- i---- -----r----r----r- ---r-
---
20- Runoff Volu'Fne =0.23$ of
-- !--- -7 - - -- - - -- ----------------
--
o Runoff FE 15
Tc =5.0 rmin
10 C =0.61
5
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 23
Summary for Subcatchment 3 -POST: DA #3 -POST
Runoff = 10.65 cfs @ 0.08 hrs, Volume= 0.076 af, Depth= 0.35"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk & Lots
1.270 0.35 Pervious
2.640 0.64 Weighted Average
2.640 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 3 -POST: DA #3 -POST
Hydrograph
10.65 cfs - - -!, - - - -!, - - - - -' - - - - -!, -! - - --
--- - - - - -- 1 - - -- 1 ---- - ----- ---- - - -- FDA -Raleigh -NCSU 5=yr-
10
- - - - - -- - - -- -- Duration'=5-rrhin;-
9
--- - - - - -- - - -- ------------------------- ,Anten=6.48- 1hthr-
8-
1---- 1--- -1 - - -- - - - -- ftunoff- Area = -2.644 ac-
,� 7•
-- - - -- - - --
3
Rup '- offiVoruLF e= 07 -a- f6 -
0 5 - -- Runoff- Oept� 0.�F-
- - -- - - -- - - -- - - -- - - - -- ----------- - - - -4- - -+
4• Tc =5.0 - - - -
min
- - - - + - - - - 1 - - - -
3 C =0.64
--- - + - - -- - - -- ---------------
2--------- -' - - -- - - -- --- - + - - --
- - - -- - - -- -------------------- --------------------+----
0. .
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Q Runoff

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 24
Summary for Pond 1 -BMP: BMP #1
Inflow Area =
9.620 ac, 0.00% Impervious, Inflow Depth = 0.31" for 5 -yr event
Inflow =
35.18 cfs @
0.08 hrs, Volume= 0.251 of
Outflow =
10.79 cfs @
0.14 hrs, Volume= 0.121 af, Atten= 69 %, Lag= 3.6 min
Primary =
10.79 cfs @
0.14 hrs, Volume= 0.121 of
Secondary =
0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind
method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 309.72' @ 0.14 hrs
Surf.Area= 8,647 sf Storage= 9,477 cf
Plug -Flow detention time= 280.0
min calculated for 0.121 of (48% of inflow)
Center -of -Mass det. time= 278.7
min ( 283.7 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 308.50' 44,258 cf Custom Stage Data (Prismatic)Listed below
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
308.50
6,032
0 0
309.00
7,838
3,468 3,468
310.00
8,969
8,404 11,871
310.50
9,555
4,631 16,502
311.00
10,156
4,928 21,430
312.00
11,400
10,778 32,208
313.00
12,700
12,050 44,258
Device Routing
Invert
Outlet Devices
#1 Primary
304.00'
15.0" Round Culvert
L= 48.4' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 304.00'/ 303.00' S=0.0207'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1
309.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1
308.50'
1.0" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =10.64 cfs @ 0.14 hrs HW= 309.71' (Free Discharge)
t = Culvert (Passes 10.64 cfs of 15.08 cfs potential flow)
2 =Weir Opening (Weir Controls 10.61 cfs @ 1.51 fps)
3 Orifice /Grate (Orifice Controls 0.03 cfs @ 5.21 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 308.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 25
•
,.
I• .•e= •
00
I
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
313
G&VA
a�
T
0 311
0
a 310
W
Pond 1 -BMP: BMP #1
Stage- Area - Storage
Surracp1w-
0 2,000 4,000
E Inflow
Outflow
❑ Primary
❑ Secondary
etted Area (sq -ft)
6,000 8,000 10,000 12,000
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 26
Summary for Pond 2 -BMP: BMP #2
Inflow Area = 8.600 ac, 0.00% Impervious, Inflow Depth = 0.33" for 5 -yr event
Inflow = 33.08 cfs @
0.08 hrs, Volume= 0.236 of
Outflow = 0.05 cfs @
0.17 hrs, Volume= 0.085 af, Atten= 100 %, Lag= 5.2 min
Primary = 0.05 cfs @
0.17 hrs, Volume= 0.085 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 311.21' @ 0.17 hrs
Surf.Area= 15,743 sf Storage= 10,250 cf
Plug -Flow detention time= 692.4
min calculated for 0.085 of (36% of inflow)
Center -of -Mass det. time= 690.5
min ( 695.5 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 310.50' 41,357 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
310.50 12,459
0 0
311.00 15,367
6,957 6,957
311.50 16,270
7,909 14,866
312.00 17,188
8,365 23,230
313.00 19,065
18,127 41,357
Device Routing Invert
Outlet Devices
#1 Primary 306.00'
15.0" Round Culvert
L= 43.0' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 306.00'/ 305.00' S=0.0233'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 311.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 310.50'
1.5" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.25'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.05 cfs @ 0.17 hrs HW= 311.21' (Free Discharge)
t = Culvert (Passes 0.05 cfs of 14.78 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.05 cfs @ 3.87 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 310.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 27
31
a�
T
31
C
0
a�
w
31
•• • •,
�i
I : .00
• .•- ,
zz
I
�I
it
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 2 -BMP: BMP #2
Stage- Area - Storage
Q „mace /Horizor +' sd Area (sq -ft)
0 5,000 10,000 15,000
E Inflow
Outflow
❑ Primary
❑ Secondary
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 28
Summary for Pond 3 -BMP: BMP #3
Inflow Area = 2.640 ac, 0.00% Impervious, Inflow Depth = 0.35" for 5 -yr event
Inflow = 10.65 cfs @
0.08 hrs, Volume= 0.076 of
Outflow = 0.01 cfs @
0.17 hrs, Volume= 0.022 af, Atten= 100 %, Lag= 5.2 min
Primary = 0.01 cfs @
0.17 hrs, Volume= 0.022 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 322.40' @ 0.17 hrs
Surf.Area= 4,267 sf Storage= 3,302 cf
Plug -Flow detention time= 701.3
min calculated for 0.022 of (29% of inflow)
Center -of -Mass det. time= 699.2
min ( 704.2 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 321.50' 11,048 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
321.50 2,429
0 0
322.00 3,980
1,602 1,602
322.85 4,596
3,645 5,247
323.00 4,709
698 5,945
324.00 5,498
5,104 11,048
Device Routing Invert
Outlet Devices
#1 Primary 317.00'
15.0" Round Culvert
L= 32.2' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 317.00'/ 316.50' S=0.0155'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 322.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 321.50'
0.7" Vert. Orifice /Grate C= 0.600
#4 Secondary 323.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.01 cfs @ 0.17 hrs HW= 322.40' (Free Discharge)
t = Culvert (Passes 0.01 cfs of 15.20 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.01 cfs @ 4.48 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 321.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 29
10.65
10
3 6
0
0.00 cfs
32
a�
T
32
C
0
a�
w
32
Pond 3 -BMP: BMP #3
Hydrograph
- -_T - -' T - - - T - - - - T- InflowAre'a=2.640 ac
Peak Ellev= 322.40'
-------- -- - - --------- -- - - - - -- -Storage =3,302 cf
- -- ------------ ------------ -- - --
_T - T T - -- T- - -
T
- --
�I I I I I I I I I I I
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 3 -BMP: BMP #3
Stage- Area - Storage
Surface /H ^ri-7nn +n1AP sd Area (sq -ft)
0 1,000 2,000 3,000 4,000
5,000
Inflow
Outflow
❑ Primary
❑ Secondary
0 5,000 10,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 30
Summary for Subcatchment 1 -POST: DA #1 -POST
Runoff = 39.09 cfs @ 0.08 hrs, Volume= 0.279 af, Depth= 0.35"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
1.520 0.90 Roads & Sidewalk
2.540 0.90 Lots
5.560 0.35 Pervious
9.620 0.58 Weighted Average
9.620 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 1 -POST: DA #1 -POST
Hydrograph
39.09 cfs - - -! - - -! - -- -----'-----'----------' Y --
t----!---------Y----
IDF- RaloighTNCSU 10- r
t- - - ,- - - - -r - r-------- -7 -
35- DurAtion*5 niin,
-;----;----;----,----- �----- �----- �----- �rinfern =7.20 iriThr-
30-
- - - flu n off - Area =-9 $20 ac -
25_ - -
T - - -- - - -- - - -- --- - -I ff -R� o oIu - 27 af_
0 20' Runoff Depth =0.$5„
15- Tc =5.0 min
- ---- rt--- -rt - - -- -------------------- 't---- t - - - -- C =0.58-
10
- - - - + - - - - t - - - - t - - - - t ----- -------------- t - - - -
5
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 31
Summary for Subcatchment 2 -POST: DA #2 -POST
Runoff = 36.75 cfs @ 0.08 hrs, Volume= 0.262 af, Depth= 0.37"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk
2.630 0.90 Lots
4.600 0.35 Pervious
8.600 0.61 Weighted Average
8.600 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 2 -POST: DA #2 -POST
Hydrograph
36.75 cfs - -- i - - -- i -- , -- -� -- - �----- �---- -� - - -- i - - -- i - - -- i - - --
- -- - - -- ----------- - - - -- -- IDF- Ra16ig- h'NCStr 40--r-
35-
- - - - ' DurAtionL=5 rhin,-
30= Inten =7.20 ih /hr
25- I I I I I I
Runoff Area =8.600 ac
-- - - -- 7 - - - - - -- -- Rupoff -Vofu e= �.26� -af-
3 20•
o - - - -- --- - + - - -- - - - -- - - - -I_ Runoff_Oeptti=0V"-
15-1 I I I I I I I
Tc =5.0 min
5
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 32
Summary for Subcatchment 3 -POST: DA #3 -POST
Runoff = 11.84 cfs @ 0.08 hrs, Volume= 0.084 af, Depth= 0.38"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk & Lots
1.270 0.35 Pervious
2.640 0.64 Weighted Average
2.640 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 3 -POST: DA #3 -POST
Hydrograph
11.84 cfs - -- - - -- - - -- - - - -- - -- -- ------ - + - - --
T--- -7 - - -- - - -- ------ ]DF,RaleighTNCSU
tO -yr-
DurAtion 5-rhin;-
10= - - -- -T - - - - --- - ------ 1nten =7.20- Ifthr9-
--- - T - - -- - - -- F un6 Area
=2.640 -a-c-
42
8" -- - -! - -- ! - -- !------------------------ - - - - -- - - -- - - -- - - --
7 Runoff Volume =0.084 -af-
- - - -- - - -- ----------------
0 6' ----- - - - -!, - - - -!, - - - -- -Runoff Oept� =""
FL5- --- - - - - -- - - -- ------------------- - - - - -- - -- Tc- =&O -min-
4 - - -- - - -- ------------------- -'r - -- - - -- C =0.64-
3-
2 - ----i----1---- J-------------------- L----L----i----i----
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Q Runoff

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 33
Summary for Pond 1 -BMP: BMP #1
Inflow Area =
9.620 ac, 0.00% Impervious, Inflow Depth = 0.35" for 10 -yr event
Inflow =
39.09 cfs @
0.08 hrs, Volume= 0.279 of
Outflow =
14.56 cfs @
0.14 hrs, Volume= 0.149 af, Atten= 63 %, Lag= 3.2 min
Primary =
14.56 cfs @
0.14 hrs, Volume= 0.149 of
Secondary =
0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind
method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 309.77' @ 0.14 hrs
Surf.Area= 8,708 sf Storage= 9,932 cf
Plug -Flow detention time= 228.8
min calculated for 0.149 of (53% of inflow)
Center -of -Mass det. time= 227.3
min ( 232.3 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 308.50' 44,258 cf Custom Stage Data (Prismatic)Listed below
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
308.50
6,032
0 0
309.00
7,838
3,468 3,468
310.00
8,969
8,404 11,871
310.50
9,555
4,631 16,502
311.00
10,156
4,928 21,430
312.00
11,400
10,778 32,208
313.00
12,700
12,050 44,258
Device Routing
Invert
Outlet Devices
#1 Primary
304.00'
15.0" Round Culvert
L= 48.4' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 304.00'/ 303.00' S=0.0207'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1
309.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1
308.50'
1.0" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =14.90 cfs @ 0.14 hrs HW= 309.77' (Free Discharge)
t = Culvert (Passes 14.90 cfs of 15.16 cfs potential flow)
2 =Weir Opening (Weir Controls 14.87 cfs @ 1.69 fps)
3 Orifice /Grate (Orifice Controls 0.03 cfs @ 5.33 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 308.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 34
Pond 1 -BMP: BMP #1
Hydrograph
39.09 cfs
inflow Area= 9.620'ac
40-
35
30
� n r
E56 cf
0.00 cfs
-- Peak Etev= 309.77'
-- - - - T Storage =-9,932 cf
- - -_T T T - -- - -- - --
------ - - - - -- -- - - - - - - - - - - ----- - - - L - - - - - - -
� - --
- -- T------- -I - - -- T- - - - --- -I - - -- T--- -I - - -- r - - -
T- - -, - --
- -- L------- -� - - -- L------- -� - - -- L - - - - L - - - 1 - -- L - --
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
313
G&VA
a�
T
0 311
0
a 310
w
Pond 1 -BMP: BMP #1
Stage- Area - Storage
E Inflow
[ Outflow
❑ Primary
❑ Secondary
Surracp1w- etted Area (sq -ft)
0 2,000 4,000 6,000 8,000 10,000 12,000
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 35
Summary for Pond 2 -BMP: BMP #2
Inflow Area = 8.600 ac, 0.00% Impervious, Inflow Depth = 0.37" for 10 -yr event
Inflow = 36.75 cfs @
0.08 hrs, Volume= 0.262 of
Outflow = 0.05 cfs @
0.17 hrs, Volume= 0.090 af, Atten= 100 %, Lag= 5.2 min
Primary = 0.05 cfs @
0.17 hrs, Volume= 0.090 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 311.28' @ 0.17 hrs
Surf.Area= 15,873 sf Storage= 11,389 cf
Plug -Flow detention time= 694.3
min calculated for 0.090 of (34% of inflow)
Center -of -Mass det. time= 692.1
min ( 697.1 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 310.50' 41,357 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
310.50 12,459
0 0
311.00 15,367
6,957 6,957
311.50 16,270
7,909 14,866
312.00 17,188
8,365 23,230
313.00 19,065
18,127 41,357
Device Routing Invert
Outlet Devices
#1 Primary 306.00'
15.0" Round Culvert
L= 43.0' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 306.00'/ 305.00' S=0.0233'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 311.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 310.50'
1.5" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.25'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.05 cfs @ 0.17 hrs HW= 311.28' (Free Discharge)
t = Culvert (Passes 0.05 cfs of 14.88 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.05 cfs @ 4.08 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 310.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 36
31
a�
T
31
C
0
a�
w
31
•
Inflow ` : . 1 i
• .•- :• cf
zz
I
it
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 2 -BMP: BMP #2
Stage- Area - Storage
Q „mace /Horizor +' sd Area (sq -ft)
0 5,000 10,000 15,000
E Inflow
[ Outflow
❑ Primary
❑ Secondary
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 37
Summary for Pond 3 -BMP: BMP #3
Inflow Area = 2.640 ac, 0.00% Impervious, Inflow Depth = 0.38" for 10 -yr event
Inflow = 11.84 cfs @
0.08 hrs, Volume= 0.084 of
Outflow = 0.01 cfs @
0.17 hrs, Volume= 0.023 af, Atten= 100 %, Lag= 5.2 min
Primary = 0.01 cfs @
0.17 hrs, Volume= 0.023 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 322.48' @ 0.17 hrs
Surf.Area= 4,329 sf Storage= 3,669 cf
Plug -Flow detention time= 702.5
min calculated for 0.023 of (28% of inflow)
Center -of -Mass det. time= 700.0
min ( 705.0 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 321.50' 11,048 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
321.50 2,429
0 0
322.00 3,980
1,602 1,602
322.85 4,596
3,645 5,247
323.00 4,709
698 5,945
324.00 5,498
5,104 11,048
Device Routing Invert
Outlet Devices
#1 Primary 317.00'
15.0" Round Culvert
L= 32.2' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 317.00'/ 316.50' S=0.0155'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 322.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 321.50'
0.7" Vert. Orifice /Grate C= 0.600
#4 Secondary 323.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.01 cfs @ 0.17 hrs HW= 322.48' (Free Discharge)
t = Culvert (Passes 0.01 cfs of 15.34 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.01 cfs @ 4.70 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 321.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 38
32
a�
T
32
C
0
a�
w
32
i�
i . -0
• .•- ..• cf
zz
�I
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 3 -BMP: BMP #3
Stage- Area - Storage
Surface /H ^ri-7nn +n1AP sd Area (sq -ft)
0 1,000 2,000 3,000 4,000 5,000
E Inflow
Outflow
❑ Primary
❑ Secondary
0 5,000 10,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 39
Summary for Subcatchment 1 -POST: DA #1 -POST
Runoff = 48.86 cfs @ 0.08 hrs, Volume= 0.348 af, Depth= 0.43"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
1.520 0.90 Roads & Sidewalk
2.540 0.90 Lots
5.560 0.35 Pervious
9.620 0.58 Weighted Average
9.620 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 1 -POST: DA #1 -POST
Hydrograph
48.86 cfs - - -! - - -! - -- -----'-----'----------'r----!---------Y----
- - -- - - -- ----- - - - - --
1DF- RaI'eigh�NOSU 100 -yr-
. --- - + - - --
45= Duration =5 ruin,
----1----1----1----J-----1---------------L-
40= Inten =6.00 in /hr
.. 35 Runoff Area =9.620 ac
,� - - - -- - - -- --- - -I - -- Runoff Volume=�0.- 348-af-
c, 30.
-
--- T--- -I - - - - - - -- ------ - - - -I- Runoff Depth --0 43 --
25'
—- - -- - - -- --- - + - - -- - - - --
0 - - - - -- Tc=-5.0 -rntn-
u_ 20.
----1----1----1----J-----1---------------L----L----1-C-=d-58-
15
10
5
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 40
Summary for Subcatchment 2 -POST: DA #2 -POST
Runoff = 45.94 cfs @ 0.08 hrs, Volume= 0.327 af, Depth= 0.46"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk
2.630 0.90 Lots
4.600 0.35 Pervious
8.600 0.61 Weighted Average
8.600 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 2 -POST: DA #2 -POST
Hydrograph
45.94 cfs - -- i - - -- i - - - -, -- -� -- - �----- �---- -� - - -- i - - -- i - - -- i - - --
45- IDF- Raleigh;NCSU 100 -yr
40- Ouration=5 rein,
--- - + - - -- - - -- - - -- ----------------------Irrtien=9,.0ain/hr-
35 _ Rurtoff Area =9.600 -ac_
30• Runoff Volume -0.327 of
7 - - - - T - - - -
3 25• Runoff, Depth = 0.,46"
---- - 1---- 1---- 1---- J----- 1 - - - -- L - - -- -1 1- --
FL 20. �c =5.� �nin
15
10
5
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
❑ Runoff

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 41
Summary for Subcatchment 3 -POST: DA #3 -POST
Runoff = 14.80 cfs @ 0.08 hrs, Volume= 0.105 af, Depth= 0.48"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
1.370 0.90 Roads & Sidewalk & Lots
1.270 0.35 Pervious
2.640 0.64 Weighted Average
2.640 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment 3 -POST: DA #3 -POST
Hydrograph
14.80 cfs - -- i - - -- i -- � -- -� -- - �----- �---- -� - - -- i -- i - - -- i - - --
- 1---- 1---- 1---- J----- 1------- iDF- Rai'eigh.,IN SU400 -yr-
14 Duration =5 min,
12 Inten =9.00 ire /hr
-
-- -T - - - - - - -- ---- ----------------- RuhoffAr-ea =2.640 ac-
,� 10 Runoff Volume "0.105 of
v
3 8 Runoff, Depth= 0.48"
—° ---- L---- L---- L---- L - - - -- L - - - - L- Tc=-5.0 -MEn-
u_ 6- I I I I I I I I I I
C =0.64
--------------------------------------------
4'
T - - - - 7 - - - - 7 - - - - - - - - T - - - - 7 - - - - T - - - -
2
0- .
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Q Runoff

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 42
Summary for Pond 1 -BMP: BMP #1
Inflow Area =
9.620 ac, 0.00% Impervious, Inflow Depth = 0.43" for 100 -yr event
Inflow =
48.86 cfs @
0.08 hrs, Volume= 0.348 of
Outflow =
15.46 cfs @
0.14 hrs, Volume= 0.218 af, Atten= 68 %, Lag= 3.5 min
Primary =
15.46 cfs @
0.14 hrs, Volume= 0.218 of
Secondary =
0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind
method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 309.99' @ 0.14 hrs
Surf.Area= 8,953 sf Storage= 11,754 cf
Plug -Flow detention time= 157.3
min calculated for 0.218 of (63% of inflow)
Center -of -Mass det. time= 156.6
min ( 161.6 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 308.50' 44,258 cf Custom Stage Data (Prismatic)Listed below
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq -ft)
(cubic -feet) (cubic -feet)
308.50
6,032
0 0
309.00
7,838
3,468 3,468
310.00
8,969
8,404 11,871
310.50
9,555
4,631 16,502
311.00
10,156
4,928 21,430
312.00
11,400
10,778 32,208
313.00
12,700
12,050 44,258
Device Routing
Invert
Outlet Devices
#1 Primary
304.00'
15.0" Round Culvert
L= 48.4' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 304.00'/ 303.00' S=0.0207'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1
309.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1
308.50'
1.0" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =15.45 cfs @ 0.14 hrs HW= 309.98' (Free Discharge)
t =Culvert (Barrel Controls 15.45 cfs @ 12.59 fps)
2 =Weir Opening (Passes < 26.82 cfs potential flow)
3 Orifice /Grate (Passes < 0.03 cfs potential flow)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 308.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 43
� i i•
•
0' 9'
I
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
313
G&VA
a�
T
0 311
0
a 310
w
Pond 1 -BMP: BMP #1
Stage- Area - Storage
Surracp1w-
0 2,000 4,000
E Inflow
Outflow
❑ Primary
❑ Secondary
etted Area (sq -ft)
6,000 8,000 10,000 12,000
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 44
Summary for Pond 2 -BMP: BMP #2
Inflow Area = 8.600 ac, 0.00% Impervious, Inflow Depth = 0.46" for 100 -yr event
Inflow = 45.94 cfs @
0.08 hrs, Volume= 0.327 of
Outflow = 0.06 cfs @
0.17 hrs, Volume= 0.101 af, Atten= 100 %, Lag= 5.2 min
Primary = 0.06 cfs @
0.17 hrs, Volume= 0.101 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 311.46' @ 0.17 hrs
Surf.Area= 16,198 sf Storage= 14,239 cf
Plug -Flow detention time= 697.0
min calculated for 0.101 of (31 % of inflow)
Center -of -Mass det. time= 695.0
min ( 700.0 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 310.50' 41,357 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
310.50 12,459
0 0
311.00 15,367
6,957 6,957
311.50 16,270
7,909 14,866
312.00 17,188
8,365 23,230
313.00 19,065
18,127 41,357
Device Routing Invert
Outlet Devices
#1 Primary 306.00'
15.0" Round Culvert
L= 43.0' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 306.00'/ 305.00' S=0.0233'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 311.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 310.50'
1.5" Vert. Orifice /Grate C= 0.600
#4 Secondary 312.25'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =0.06 cfs @ 0.17 hrs HW= 311.46' (Free Discharge)
t = Culvert (Passes 0.06 cfs of 15.15 cfs potential flow)
2 =Weir Opening ( Controls 0.00 cfs)
3 Orifice /Grate (Orifice Controls 0.06 cfs @ 4.56 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 310.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 45
31
a�
T
31
C
0
a�
w
31
I � I
Peak -.
Storage-14,239
zz
�I
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 2 -BMP: BMP #2
Stage- Area - Storage
Q „mace /Horizor +' sd Area (sq -ft)
0 5,000 10,000 15,000
F Inflow
Outflow
❑ Primary
❑ Secondary
0 10,000 20,000 30,000 40,000
Storage (cubic -feet)
Surface
❑ Storage

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 46
Summary for Pond 3 -BMP: BMP #3
Inflow Area = 2.640 ac, 0.00% Impervious, Inflow Depth = 0.48" for 100 -yr event
Inflow = 14.80 cfs @
0.08 hrs, Volume= 0.105 of
Outflow = 3.72 cfs @
0.15 hrs, Volume= 0.042 af, Atten= 75 %, Lag= 3.9 min
Primary = 3.72 cfs @
0.15 hrs, Volume= 0.042 of
Secondary = 0.00 cfs @
0.00 hrs, Volume= 0.000 of
Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
Peak Elev= 322.61' @ 0.15 hrs
Surf.Area= 4,419 sf Storage= 4,199 cf
Plug -Flow detention time= 391.6
min calculated for 0.042 of (40% of inflow)
Center -of -Mass det. time= 389.6
min ( 394.6 - 5.0 )
Volume Invert Avail.Storage Storage Description
#1 321.50' 11,048 cf Custom Stage Data (Prismatic)Listed below
Elevation Surf.Area
Inc.Store Cum.Store
(feet) (sq -ft)
(cubic -feet) (cubic -feet)
321.50 2,429
0 0
322.00 3,980
1,602 1,602
322.85 4,596
3,645 5,247
323.00 4,709
698 5,945
324.00 5,498
5,104 11,048
Device Routing Invert
Outlet Devices
#1 Primary 317.00'
15.0" Round Culvert
L= 32.2' RCP, groove end projecting, Ke= 0.200
Inlet/ Outlet Invert= 317.00'/ 316.50' S=0.0155'/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 322.50'
6.0" x 192.0" Horiz. Weir Opening C= 0.600
Limited to weir flow at low heads
#3 Device 1 321.50'
0.7" Vert. Orifice /Grate C= 0.600
#4 Secondary 323.00'
15.0' long x 8.0' breadth Broad - Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64
2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74
Primary OutFlow Max =3.64 cfs @ 0.15 hrs HW= 322.60' (Free Discharge)
t = Culvert (Passes 3.64 cfs of 15.53 cfs potential flow)
2 =Weir Opening (Weir Controls 3.63 cfs @ 1.06 fps)
3 Orifice /Grate (Orifice Controls 0.01 cfs @ 4.99 fps)
t condary OutFlow Max =0.00 cfs @ 0.00 hrs HW= 321.50' (Free Discharge)
4= Broad -Crested Rectangular Weir( Controls 0.00 cfs)

Pond Routing IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/7/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 47
.'
Peak Elev=322 -61
•
' I • .•- .. cf
ff@Ylnl
I
32
a�
T
32
C
0
a�
w
32
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)
Pond 3 -BMP: BMP #3
Stage- Area - Storage
Surface /H ^ri-7nn +n1AP sd Area (sq -ft)
0 1,000 2,000 3,000 4,000 5,000
E Inflow
Outflow
❑ Primary
❑ Secondary
0 5,000 10,000
Storage (cubic -feet)
Surface
❑ Storage

PRE -3 POST -3
DA #3 -PRE DA #3 POST
PRE -1 POST -1
DA #1 -PRE DA 1 -POST
PRE -2 POST -2
DA #2 -PRE DA #2 -POST
Subcat Reach on Link
E Hydr.CAD@ Routing Diagram for 140710 Site Pre -Post
Prepared by Bohler Engineering, Printed 7/9/2014
10.00 s/n 07811 © 2013 Hydro CAD Software Solutions LLC

140710 Site Pre -Post
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area C Description
(acres) (s u bcatch me nt-n u mbe rs)
248.400 0.70 Composite C (POST -1, POST -2, POST -3)
269.200 0.70 Composite C (PRE -1, PRE -2, PRE -3)
517.600 0.70 TOTAL AREA

140710 Site Pre -Post IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment POST -1: DA 1 -POST
Runoff = 149.41 cfs @ 0.08 hrs, Volume= 1.065 af, Depth= 0.28"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
45.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -1: DA 1 -POST
Hydrograph
149.41 cfs
- -- ------ - - -- - - - - -- 0 Runoff
--------------------------- - - - - -- ]DF-Releigh- NCSU -1 -yr-
140 Duration =5 min,
120 Inten =480 irk /hr
- - - -' r---- r-------------- Runoff Area =45 -706 ac -
.T 100 Runoff Volume= 11.065 of
v
3 80 RLjnoffDepth= 0.28"
° T'C 5.0 -ray i r} -
u- 60
C =0.70
40
- - -- - -- r--- -r - - -- - - -- r--- -r - - --
20 1
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment POST -2: DA #2 -POST
Runoff = 359.64 cfs @ 0.08 hrs, Volume= 2.563 af, Depth= 0.28"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
110.000 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -2: DA #2 -POST
Hydrograph
- - -- --- - - - - -- - - -- -
359.64 cfs 0 Runoff
350 - -- - -- - -- - -- - -- - -- - -- IDF - Raleigh-NCSU 1 -yr
- - - -' ---------r----r---------------------Duratio-p=&minr-
300 Inten =480 irk /hr
N 250
-- - -- RunoffArea =111Q.00a ac -
Runoff Volume =2.568 of
3 200 RLjnoffDepth= 0.28"
o - - -- - - - -I r--- -r - - -- - -- - T-C=5.0- rnirr-
'� 150 I I I I I I I I I I '
C =0.70
---- L--------- L--- -L - - -- - - -- -
---L----L---------L---- L
----
100
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment POST -3: DA #3 POST
Runoff = 303.08 cfs @ 0.08 hrs, Volume= 2.160 af, Depth= 0.28"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
92.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -3: DA #3 POST
Hydrograph
303.08 cfs Q Runoff
300 IDF - Raleigh -NCSU 1 -yr
- ---------- r--- -r - - -- - - -- - - - -' ---- '_Duratio _n=5 rain,
250 Inten =480 irk /hr
- - - -' - - -- - - --
-------- Runoff Area=92 -706 ac
v
200 Runoff Volume= 12.160 of
- - - - - -R4noff,Depth =a 28"
0 150 Tc =5.0 min
- - - - -- - -- - - - - -- -C=010
100
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment PRE -1: DA #1 -PRE
Runoff = 180.80 cfs @ 0.08 hrs, Volume= 1.288 af, Depth= 0.28"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
55.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -1: DA #1 -PRE
Hydrograph
180.80 cfs Q Runoff
180 IDF - Raleigh -NCSU 1 -yr
160 I Duration =5 min,
140 ---- --tnten= 4,80- ir�fhr-
- - - -' --------- ---- - - - - -- - - -- --- Runoff Area= 55.306ar_-
v
120 Runoff Volume= 11.288 of
3 100 RLjnoff, Depth= 0.28"
80 Tc =5.0 rn i n
60 - - - -I - - - -I - - - -I - - - -I - - - -I - - - -
40
20
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment PRE -2: DA #2 -PRE
Runoff = 387.75 cfs @ 0.08 hrs, Volume= 2.763 af, Depth= 0.28"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
118.600 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -2: DA #2 -PRE
Hydrograph
387.75 cfs ---' ----- 0 Runoff
---- --- --- --- --- --- IDF - Ralei _qh- NCSU_l -yr_
350 Duration =5 min,
300 Runoff A een= 480- ir�fhr-
------- - - - - -- --- --- --- --- - - - - -- a #11$.600 ac
------ Area-- --
250 Runoff Volume #2.763 of
----' r--------- r---- r---- r---- r---- 'r-- R -4no#f',-Depth= i-.28 "-
0 200
— Tv=5.0nIin-
150 C =0.70
100
50
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment PRE -3: DA #3 -PRE
Runoff = 311.58 cfs @ 0.08 hrs, Volume= 2.220 af, Depth= 0.28"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 1 -yr Duration =5 min, Inten =4.80 in /hr
Area (ac) C Description
95.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -3: DA #3 -PRE
Hydrograph
311.58 cfs Q Runoff
300 1DF= Raleigh =N U_1__r
---- r---- r Duration =5 min,
r---- r---- ,
250 rI r I r r Inten =480 iri%hr
Runoff Area = 95.300 ac
200 Runoff Volume #2.220 of
-- R4n off ',Depth =0 2X' -
0 150 Tc =5.0 min
---- 'r - - - -I- - -r - -r- - -r- -- r---- 'r---- 'r--------- rC =0�.70-
100
-- - - -r - - -r- - -r- - -r- - -r -- -r----r---------r----r----
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 9
Summary for Subcatchment POST -1: DA 1 -POST
Runoff = 175.56 cfs @ 0.08 hrs, Volume= 1.251 af, Depth= 0.33"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
45.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -1: DA 1 -POST
Hydrograph
175.56 cfs - - -'r ---- !---- !---- !--- -! - - -- !--- -! - - -- pRunoff
- - -- - -- - -- - -- - -- - -- IDF - Raleigh- NCSU_2 -yr_
160 Duration =5 min,
---- r---- r---- r---- r---- r--- -r - - -- r-Inten =5x64 i 61 r
140
---------------------------------- RLmoff Area=4510d a -c -
,� 120 - RU noff -Volu me=,-1-2.51 -af -
3 100
---- �----- �---------------------------- Ronoff,Depth =0.33" _
° 80 Tc =5.0 min
60 - - - -, .7II-
40
---- L--------- L--- -L - - -- - - -- ----L----L---------L----r----
20
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 10
Summary for Subcatchment POST -2: DA #2 -POST
Runoff = 422.57 cfs @ 0.08 hrs, Volume= 3.011 af, Depth= 0.33"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
110.000 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -2: DA #2 -POST
Hydrograph
422.57 cfs -- -- - - - - -- -- -- -- -- - - -- p Runoff
- - -- - -- - -- - -- - -- - -- -- -IDF- Raleigh= NCS- Ul2ryr-
400
---- r---- -Du
ratio-n=5 mint -
350 Inten =564 irk /hr
-------------------
N 300 Runoff Area= 110.000 ac
`� -------- -' - - -- - -- - -- - -- -
Runoff -Volume =3FA I-af-
250
3 ---- L---- L---- r---- L---- L---- L---- L-- R-4noff,Depth =0 33 "_
2 200 Tc =5.0 min
---- r---- r---- r---- r---- r---- r---- r---- r---- r - - - -r C_ -----
150
100
---- L--------- L--- -L - - -- - - -- ----L----L---------L----L----
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 11
Summary for Subcatchment POST -3: DA #3 POST
Runoff = 356.11 cfs @ 0.08 hrs, Volume= 2.537 af, Depth= 0.33"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
92.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -3: DA #3 POST
Hydrograph
356.11 cfs Q Runoff
350 IDF - Raleigh -NCSU 2 -yr
- - -- -Duration =5mEn, -
300 Inten =564 irk /hr
N 250
-- - -r - -- - -- - -- - -- - --
--- IRuno'ffArea=g2.700r ac-
---- 'L ---- I L --- - L - - -- Run_offLyQlume= 2.537_af
3 200 Rwnoff',Depth= 0.33"
o --------- L---- r---- L--- -L - - -- - -- - T5.0 -rnirr-
'� 150 I I I I I I I I I I '
C =0.70
100
50j/
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 12
Summary for Subcatchment PRE -1: DA #1 -PRE
Runoff = 212.44 cfs @ 0.08 hrs, Volume= 1.514 af, Depth= 0.33"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
55.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -1: DA #1 -PRE
Hydrograph
212.44 cfs ---'--------------------------------------------
- - - - -- 0 Runoff
- --- L---------
L--- -L - - -- L -
- -- L -
-- IDF =Rafe gh=NCS -Ul 2 -yr-
200 -
--- L---- -----
L --- - L - - -- -
- -- ----
L - - - - L -
-Du ration =& m In, -
180
- - -- ---------
L--- -L - - -- -
- -- ---
-L - - -- - L
Inten= 5,64 -' 11hr-
160 ---- ' L ---- '-----
L ---- L ---- L ----
L ---
Runoff Area= 55.306 ar--
140 - - - -'L
L L L
L__Run_offLVo1Ume=
,_t514_af_
3 120
---- L ---- -----
L ---- L ---- L ----
L ----
L-- R4noff,Deph =0.3 "_
0 100
M- - - - � - - - - -----
L - - - - I - - - - I -
- - - I -
Tc =5.0 ml i n
- - - I - - - - - - - - - - - - - - - - - - - - - -
80
C =0.70
60
40
----r---------r----r----r----r----r----r---------r----r----
20
0
0 2 4
6 8 10
12
14 16 18 20 22 24
Time
(hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 13
Summary for Subcatchment PRE -2: DA #2 -PRE
Runoff = 455.61 cfs @ 0.08 hrs, Volume= 3.246 af, Depth= 0.33"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
118.600 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -2: DA #2 -PRE
Hydrograph
455.61 cfs 0 Runoff
---r----r----r----r----r----r----r----r----r----r----
450 IDF - Raleigh -NCSU 2 -yr
400
--- -r - - -- - - - -r- r- r- r- r----r-tnten= 5-64- irhFhr-
350 ---- L ---- ----- L ---- L ---- L ---- L-- Runoff Ar-ea =118.604 ar--
300 Runoff Volume =3.246 of
_- - - -- --------- r--- -r - - -- ------- --------- --- ----- r ---- r ----
3 250 RLjnoffDepth= 0.33"
iz 200 Tc =5.0 min
150 - - - -I - - - -I - - - -I - - - -I - - - -I - - - - -- -C= 0�.7a-
- - -- ------------------ -- - - -- - - -- - - -- --- - - - - -- - - -- - - --
100
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment PRE -3: DA #3 -PRE
Runoff = 366.10 cfs @ 0.08 hrs, Volume= 2.609 af, Depth= 0.33"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 2 -yr Duration =5 min, Inten =5.64 in /hr
Area (ac) C Description
95.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -3: DA #3 -PRE
Hydrograph
366.10 cfs 0 Runoff
- - -- - -- - -- - - - -i - - - -i - - - -,-- -1[7F= Raleigh -NCSU 2yr-
350
- - - -' - - - -' - - -- ---- ----- ----- ------ '-- DurOon =5 m, in,
300 Inten =564 irk /hr
-Runoff 250
0 Runoff Volume #2.609 of
-I- - - - - r - - - - r - - - - r - - - - r - - - - r - - - - r - - - -I----- r - - - - -
3 200 RLjnoffDepth= 0.33"
2 ---- L --- - - - - -- - - -- - - -- - - -- - - - -' - - - -' ------ T 'C-=5.0- rnirr-
" 150 I I I I I I I I I I '
C =0.70
---- L--------- L--- -L - - -- - - -- -
---L----L ---- -----L ---- L----
100
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 15
Summary for Subcatchment POST -1: DA 1 -POST
Runoff = 201.71 cfs @ 0.08 hrs, Volume= 1.437 af, Depth= 0.38"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
45.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -1: DA 1 -POST
Hydrograph
201.71 cfs 0 Runoff
200 IDF - Raleigh -NCSU 5 -yr
180 Duration =5 min,
- - -- -------- - } - - -- - - -- - - -- - - -- - - - -1- Intl - --- 8 iri %hr
160 -
- - -- - -- - -- - -- - -- - -- Runoff Area --4510a ac -
N 140
- - -- - -------- L ---- L ---- L ---- L - - RUno f Vblume--t.*37-af-
--
120 I I I 1
0 100 - -- - -- - -- - -- - -- - -- - - - -I - -R4nof #'I]Depth =a3$ "-
-
-- - -- - -- -- - -- - -- - -- - -- - -- - -- - C =9- 70
60
- -- - - - - - - - -- F - - - - -- I - - - - - - - - - - - - - -- F - - --
40
----------------------------------- - - -- - - --
20
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 16
Summary for Subcatchment POST -2: DA #2 -POST
Runoff = 485.51 cfs @ 0.08 hrs, Volume= 3.459 af, Depth= 0.38"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
110.000 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -2: DA #2 -POST
Hydrograph
485.51 cfs - - -' - - - -- p Runoff
-- aDF- RaIejgh -NCSU 5 -yr-
450
- - -- - - -- - - -- - - -- - - -- - - -- - - -- - Dur•atior) =5 min,-
400 Inten =t48 ir7 /hr
-
--- L---- ----- L ---- L ---- L ---- L - - - - L - L ---- ----- L- ---L ----
.. 350 Runoff Area= 110.000 ac
N-- - - - - -- ------- - - - - --
300 Runoff Volume #3.459 of
----' r--------- r---- r---- r---- r---- 'r-- R4no#f',Depth= O-.38 "-
0 250
_ ----r----r----r----r----r----r----r----r----r-Tc=5.0-rnirr-
" 200
-
--- L---- L---- L---- L ---- L ---- L ---- L ---- L ---- - - - - -r C =(.70 -
150
100
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 17
Summary for Subcatchment POST -3: DA #3 POST
Runoff = 409.15 cfs @ 0.08 hrs, Volume= 2.915 af, Depth= 0.38"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
92.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -3: DA #3 POST
Hydrograph
409.15 cfs 0 Runoff
-�- - - - - L - - - - L - - - - L - - - - L - - - - L - - - - L - - - -I - __L--- - L ---
-
400 IDF- Raleigh -NCSU 5 -yr
- - - -' - - - -' - - -- - - -- - - -- ---- L------ Duratio-n=&min, -
350 I I I I I I I I
----' r--------- r---- r---- r---- r---- 'r---- 'r- Int -- --- 48- iQ-- --
300 Runoff Area = 92.700 ac
- -- ---- --- ---- --------- -- ---- --- -- ---- ---------R--u-n- ff- VoFume =2.9T5 of -
250 '
R4noff,�ep h =Q38 "-
0 200 Tc =5.0 min
FL 150 C =0.70
-
---L----L---- L ---- L ---- L ---- L ---- L ---- L ----L---- L ---- L----
100
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 18
Summary for Subcatchment PRE -1: DA #1 -PRE
Runoff = 244.08 cfs @ 0.08 hrs, Volume= 1.739 af, Depth= 0.38"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
55.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -1: DA #1 -PRE
Hydrograph
244.08 cfs - - -' ---- !---- !---- !--- -! - - -- -- !--- -! - - -- pRunoff
IDF - Raleigh -NCSU 5 -yr
- - -- ------------------------ - Dur•atior) =5 min,-
200 Inten=t 48 in /hr
Runoff Area = 55.300 ac
`� - - -- - -- --- - - - - -- RUnoff- VoFUme =1.739 of
150
3 RLjnoff Depth= 0.38"
2 --- -' --- -- -- -- - -- - - - -' - - - -' - - -- TC =5.0 -ruin
LL 100 I I I I I I I I I I '
C =0.70
50
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 19
Summary for Subcatchment PRE -2: DA #2 -PRE
Runoff = 523.47 cfs @ 0.08 hrs, Volume= 3.730 af, Depth= 0.38"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
118.600 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -2: DA #2 -PRE
Hydrograph
523.47 cfs - - -',
--------------------
'r---- 'r - - - -', ------ - - - - -- 10 Runoff
---- r - - - -,
500
- - - -; - - - -i - - - -i -
- - -, --
-IDF= Raleigh -NCSU 5yr-
---- r---- r----
450
r---- r---- r----
r----
r - - - - r -
Du ration =5- rr i n, -
---- r---- -----
r---- r---- r -
- - -r-
r---- r- Inten =6 48- ir�1hr-
400
----r----r----r----r----r----r-
- Runoff Ar -ea =1-18 60d ac -
,0 350
Ci ---- r---- r----
r---- r---- r -
- - -1
RunoffrVolume =3. 30 -af -
_. 300
- -- - --
- --
- -- - R4noff,IDep h =O 3N "-
° 250
LL r----r----r----r----r----r----r----r----r----r----r----
— - - --
Tc =5.0 rn i n
200
C =0.70
150
100
50
0
0 2 4
6 8 10
12
14 16 18 20 22 24
Time
(hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 20
Summary for Subcatchment PRE -3: DA #3 -PRE
Runoff = 420.63 cfs @ 0.08 hrs, Volume= 2.997 af, Depth= 0.38"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 5 -yr Duration =5 min, Inten =6.48 in /hr
Area (ac) C Description
95.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -3: DA #3 -PRE
Hydrograph
420.63 cfs
- - - - - -- - -- - - - -- - -- - - -- 0 Runoff
- - -- - -- - -- - -- - -- -- -IDF- Raleigh= NCS- Ul5=yr-
400 _Durzti 5L in
350 Inten =648 irk /hr
------------------------
N 300 Runoff Area = 95.300 ac
- - -- - -- - -- - -- - -- - -- --Rdnoff- volume -- x`2.997 -af-
-- 250 I I I 1
3 - - -- --------- +--- - - - - -- - - -- - - -- -- R-4n off ,Depth =9 3V "-
2 200 Tc =5.0 min
LL
150 C =0.70
100
- - -- ------------------------------------------------------
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 21
Summary for Subcatchment POST -1: DA 1 -POST
Runoff = 224.12 cfs @ 0.08 hrs, Volume= 1.597 af, Depth= 0.42"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
45.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -1: DA 1 -POST
Hydrograph
0 Runo
224.12 cfs
- - - - - -- - -- - - - -- - -- - - -- ff
220 IDF- Raleigh -NCSU 10 -yr
200 Duration =5 min,
180 Inten=t 20 in /hr
------------------------
N 160 Runoff Area = 45.700 ac
-------------------------------
140 Runoff Volume #1.597 of
3 120 Runoff, Depth =0.42"
----r---------r----r----r----r----r----r----r----r----r----
100 1 Tc =5.0 min
------- - - - - -- - -- - -- - -- - - - - - - - - --- - - - - - - - - - - - --
80 C =0.70
60
40
-- --------- - - - - -- - - -- - - -- - - -- - - -- --- - - - - -- - - -- - - --
20
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 22
Summary for Subcatchment POST -2: DA #2 -POST
Runoff = 539.45 cfs @ 0.08 hrs, Volume= 3.844 af, Depth= 0.42"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
110.000 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -2: DA #2 -POST
Hydrograph
- - -- --- - - - - -- - - -- -
539.45 cfs --- r---- ! - - - -- - !---- !---- 'r---- 'r - - -- !--- -! - - -- pRunoff
1 -0 -yr-
----r----r----r----r----r----r-
500 ----' r--------- r ---- r ---- r ---- r---- 'r - - - -'r -Duration =5Lm in,
-
450 lnten =t 20_'1 /Jhr _
---- r---- r---- r---- r---- r---- r---- r - - - -r- - t
400 - - -- - -- - -- - -- - -- RunoffAr_ea_ =_'110.000 a-o_
350 Runoff Volume= 13.844 of
3 300 - - -- - - -- - -- - -- - -- Runoff ,Deptlh =0.!12"
ro 250 - Tc =5.0 min
200 C =0.70
- --- L--------- L ---- L ---- L ---- L ---- L ---- L ---- ----- L --- - L - - --
150
----r----r----r----r----r----r----r----r----r----r----r---
100
----r---------r----r----r----r----r----r----r----r----r--
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 23
Summary for Subcatchment POST -3: DA #3 POST
Runoff = 454.61 cfs @ 0.08 hrs, Volume= 3.239 af, Depth= 0.42"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
92.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -3: DA #3 POST
Hydrograph
454.61 CfS 0 Runoff
---r----r----r----r----r----r----r----r----r----r----
450 IDF- Raleigh -NCSU 10 -yr
400
350 ------tnten= 7,20- ir�fhr-
- - - -' --------- ---- - - - - -- - - -- ---Runoff Area=192-70d-ac-
v
300 Runoff Volume =3.239 of
3 250
Runoff '
, Depth =0.42"
iz 200 Tc =5.0 min
150 - - - -I - - - -I - - - -I - - - -I - - - -I - - - - -- -C=0�10-
- - -- ------------------ -- - - -- - - -- - - -- --- - - - - -- - - -- - - --
100
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 24
Summary for Subcatchment PRE -1: DA #1 -PRE
Runoff = 271.20 cfs @ 0.08 hrs, Volume= 1.932 af, Depth= 0.42"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
55.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -1: DA #1 -PRE
Hydrograph
271.20 cfs Q Runoff
11� -yr-
250 Duration =5 min,
r lnten= 7.20 - [P/hr-
200 Runoff Area = 55.300 ac
°
Runoff Volume #1.932 of
3 150 Runoff, Depth =0.42"
° Tc =5.0 min
LL- - -- - -- - -
100 C =0.70
50
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 25
Summary for Subcatchment PRE -2: DA #2 -PRE
Runoff = 581.63 cfs @ 0.08 hrs, Volume= 4.144 af, Depth= 0.42"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
118.600 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -2: DA #2 -PRE
Hydrograph
581.63 cfs - - -' - - - -- p Runoff
-
-- L--------- L--- -L - - -- L - - -- L - -FDF Raleigh -NGS 1 -0-yr-
550
- - - -r Dur�atiori=5 rr 1n, -
---- r---- r---- r---- r---- r---- r---- r
500
- -- - -- - -- - -- - -- - -- - -- ------tnten= 720- ir�fhr-
450 -
--- L- -------- L --- -L - - -- - - -- -- RUnoffArea =TI8 600ac-
n 400
-------------- +--------- ----- -RUnoff-Volume= 4.144 -af-
" 350
----'r---------r----r----r----r----'r--Rtnoff',- Depth =O -AV-
0 300 -
9 250 -T-C=5-.O- rn i n -
200
150
---- �--------- r---- r---- �---- �---- �---- �--------- r--- -r - - --
i
100 -- ---- - - - - -- - - -- - - -- - - -- - - - -' - - - -' --- - - - - -- - - -- - - --
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 26
Summary for Subcatchment PRE -3: DA #3 -PRE
Runoff = 467.36 cfs @ 0.08 hrs, Volume= 3.330 af, Depth= 0.42"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 10 -yr Duration =5 min, Inten =7.20 in /hr
Area (ac) C Description
95.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -3: DA #3 -PRE
Hydrograph
467.36 cfs
- - - ------ - -- - ------ - -- - - -- Q Runoff
450 - -- - -- ----- - -- - -- - -- IDF= Raleigh -NCSU 10 -_r
- - - -' - - - -' - - - -- - - -- - - -- - - - -' - - -- — Duration =&min, -
400
- - -- - - -- - -- - -- - -- ----------- inten =t20A 1/hr-
350 Runoff Area = 95.300 ac
300 Runoff Volume #3.330 of
3 250 Rwnoff�,Depth =0.42"
° rc =5.0 -r in -
200 /�
---- r---- r---- r---- r---- r---- r---- r---- r----------- C=O� TG -
150
100
----------r----r----r----r----r--------------r----r----
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 27
Summary for Subcatchment POST -1: DA 1 -POST
Runoff = 280.15 cfs @ 0.08 hrs, Volume= 1.996 af, Depth= 0.52"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
45.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -1: DA 1 -POST
280.15 cfs -- --
250
N 200
v
I I
3 150
0
100
50 - -,
0 2 4 6
Hydrograph
-! - - -- - - - - -! - - - -! - - -- 0 Runoff
IDF- Raloigh =NCSU 100 -yr
--r----r-- --r---- r ---- ----- r ---- r ----
Duration =5 min,
Inten =9 00 in /hr
------------------------
Runoff Area = 45.700 ac
Runoff Volume= 11.996 of
RLjnoffDepth= 0.52"
Tc =5.0 min
- - -- ------- - - - - -- - - - --
C =0.70
8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 28
Summary for Subcatchment POST -2: DA #2 -POST
Runoff = 674.32 cfs @ 0.08 hrs, Volume= 4.805 af, Depth= 0.52"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
110.000 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -2: DA #2 -POST
Hydrograph
674.32 cfs - - -' - - - -- 0 Runoff
OF- Raleigh -NCSU 100 -yr
- - -- -------- - + - - -- - - -- - - -- - - -- - - -- ---------+----' - - --
600 Duration =5 min,
lnten= 9.00 -' /-hr-
500 Runoff Area = 110.000 ac
`� - - -- L---- L---- L - - - -L- RdnoffVo[ume=4.805 af -
-- 400 I I I 1
3 Runoff, Depth =0.52"
----r---------r----r----r----r----r----r----r----r----r----
rL 300 Tc =5.0 min
-- - - - - -- -- I ---- ---- ---- ---I -------- C=0 70
-- - -- - - - -- -
200
- -- -- - -L - -L- - -L- -L----L---------L----L----
100
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 29
Summary for Subcatchment POST -3: DA #3 POST
Runoff = 568.27 cfs @ 0.08 hrs, Volume= 4.049 af, Depth= 0.52"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
92.700 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment POST -3: DA #3 POST
Hydrograph
568.27 cfs -- - -- - -- - - - - r--- -'r - -- - -- - -- - - -- 10 Runoff
550 - -- F - - - - IF - - - - ,I - - -- 1DF_- Ra10igh_NCSU1 _G0 =yr -Duration- m1n,
500 _
450 ---- r---- r---- r---- r---- r---- r--- -r - - -- -Inten =9,00 in/hr
N 400
-- - -r - -- - -- - -- - -- - -- Runoff Area= 9 .70 ac
-------- - - - - --
350 Runoff Volume= 4.049 of
---- L---- �----- L---- L---- L ---- L ---- L-- �noffDepth =0.52..
�,
3 300 R
r---- r---- r---- r---- r---- r r r
250 Tc =r 5- - .0 - - min
---- r---- ---- r---- -
C -0.70
200
150
100
-- --------- - - - - -- - - -- - - -- - - -- - - -- --- - - - - -- - - -- - - --
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 30
Summary for Subcatchment PRE -1: DA #1 -PRE
Runoff = 339.00 cfs @ 0.08 hrs, Volume= 2.416 af, Depth= 0.52"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
55.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -1: DA #1 -PRE
Hydrograph
I 339.00 cfs - - -' - - - -- 0 Runoff
OF- Raleigh -NCSU 100 -yr
- - -- L ---- L---- L ---- L - - - - L - L--------- L--- -L - - --
300 Duration =5 min,
1nten= 9.00_ir1/hr-
250 Runoff Area = 55.300 ac
- - -- - - - - -I - - - -I - - - -I - - - -'- --Runoff-Vo[ume=2.4t6-af-
200
3 Runoff, Depth= 0.52"
- - - - - - -�- - - - - - - - - - - - - - - - - - - - - - - ----- - - - - I - - - - - - - -
150 Tc =5.0 min
C =0.70
100
--- -L - - -- - - - -L - -L- - _L- -L----L---------L----L----
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 31
Summary for Subcatchment PRE -2: DA #2 -PRE
Runoff = 727.04 cfs @ 0.08 hrs, Volume= 5.180 af, Depth= 0.52"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
118.600 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -2: DA #2 -PRE
Hydrograph
727.04 CfS 0 Runoff
700 - -- - -- - -- - -- - -- - - - -I - �DF-Rai�igh= NCSU100 -yr-
- - - -' --------- r--- -r - - -- - - -- - - - -' ---- '_Duratio _n=5 min,--
600 Inten =900 irk /hr
-
--- L--------- L---- L------ - - - - -- Runoff Area= TI8.600ac-
n 500
Runoff Volume #15.180 of
3 400 Ronoff',Depth# 0.52"
2 ----'r---------r---- r----r----r---- 'r---- 'r------ �c=5.0- rnirr-
" 300 I I I I I I I I I I '
C =0.70
---- L---- ----- L ---- L ---- L ---- L ---- L ---- L---- ----- L --- - L
- - --
200
100
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

140710 Site Pre -Post IDF- Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Prepared by Bohler Engineering Printed 7/9/2014
HydroCAD® 10.00 s/n 07811 @2013 HydroCAD Software Solutions LLC Page 32
Summary for Subcatchment PRE -3: DA #3 -PRE
Runoff = 584.20 cfs @ 0.08 hrs, Volume= 4.163 af, Depth= 0.52"
Runoff by Rational method, Rise /Fall= 1.0/1.0 xTc, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs
IDF - Raleigh -NCSU 100 -yr Duration =5 min, Inten =9.00 in /hr
Area (ac) C Description
95.300 0.70 Composite C
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft /sec) (cfs)
5.0 Direct Entry,
Subcatchment PRE -3: DA #3 -PRE
Hydrograph
- - -- --- - - - - -- - - -- -
584.20 cfs - - -' ---- ! - - - -- - !- -- -! - - -- !--- -! - - -- pRunoff
---- L --------- L---- L---- L --- - L -
tDP -Rat igh- PtCSU1� -tr-
550 - Duration =&min, -
450 ------tnten= 900- ir�fhr-
400 - -- - -- - -- - -- - -- - - - -I ---- RunoffArea=95 -30d a -c -
- - -- ------------------------ �-- RiAnoff-Votume= 4.1-63 af-
" 350
----' r--------- r---- r---- r---- r---- 'r-- Rtmoff',- Depr(h= i�52"-
0 300
- - -- - - -- - -- - -- - --
FL 250 rc =5 -0 -rn in -
200
- - -- - -------- r ---- r ---- r ---- r --- - r - - -- ---------r----r----
150
100 -- ---- - - - - -- - - -- - - -- - - -- - - - -' - - - -' --- - - - - -- - - -- - - --
50
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

PRE -POST SUMMARY
Project Name Indian Wells Subdivision
Bohler Project � NCR142011
EACH POINT OF INTEREST HAS BEEN STUDIED TO ENSURE THAT THERE WILL BE NO NEGATIVE DOWNSTREAM IMPACT. TOTAL
OFF -SITE DRAINAGE AREA IS INCLUDED IN THIS ANALYSIS.
ALL BMP'S HAVE BEEN DESIGNED IN ACCORDNACE WITH THE NCDWQ BMP MANUAL AND TOWN OF CARY STANDARDS TO
PROVIDE SUFFICIENT PRE -POST STORAGE TO MEET REQUIREMENTS FOR THE 1, 2, 5, & 10 YEAR STORMS. THE BMP'S HAVE
ALSO BEEN DESIGNED TO HAVE A MINIMUM OF 1' OF FREE BOARD IN THE 100 -YEAR STORM.
INTENSITIES ARE BASED ON NOAA Atlas 14, Vol.2
1, = 4.80 in. /hr.
12 = 5.64 in. /hr.
15 = 6.48 in. /hr.
110 = 7.20 in. /hr.
1100 = 9.00 in. /hr.
Q1
(Cfs)
QZ
(Cfs)
Q5
(Cfs)
010 (Cfs)
0100 (Cfs)
PRE
POST
PRE
POST
PRE
POST
PRE
POST
PRE
POST
POINT 1
180.80
150.37
212.44
181.40
244.08
212.49
271.20
238.68
339.00
295.61
POINT 2
387.80
359.90
455.60
423.00
523.50
486.00
581.60
540.00
727.00
675.10
POINT 3
311.60
308.81
1 366.10
356.12
1 420.63
409.16
467.36
454.62
1 727.00
571.99
TOTAL SITE
1 880.20
1 819.08
1 1034.14
1 960.52
1 1188.21
1 1107.65
1320.16
1 1233.30
1 1793.00
1 1542.70
EACH POINT OF INTEREST HAS BEEN STUDIED TO ENSURE THAT THERE WILL BE NO NEGATIVE DOWNSTREAM IMPACT. TOTAL
OFF -SITE DRAINAGE AREA IS INCLUDED IN THIS ANALYSIS.
ALL BMP'S HAVE BEEN DESIGNED IN ACCORDNACE WITH THE NCDWQ BMP MANUAL AND TOWN OF CARY STANDARDS TO
PROVIDE SUFFICIENT PRE -POST STORAGE TO MEET REQUIREMENTS FOR THE 1, 2, 5, & 10 YEAR STORMS. THE BMP'S HAVE
ALSO BEEN DESIGNED TO HAVE A MINIMUM OF 1' OF FREE BOARD IN THE 100 -YEAR STORM.
INTENSITIES ARE BASED ON NOAA Atlas 14, Vol.2
1, = 4.80 in. /hr.
12 = 5.64 in. /hr.
15 = 6.48 in. /hr.
110 = 7.20 in. /hr.
1100 = 9.00 in. /hr.

APPENDIX C
NUTRIENT LOADING CALCULATIONS

Watershed CharacteristicsVer2.0 ' Clear All Values Return to Instructions Proceed to BMP Characteristics I ' Skip to Development Summary
Instructions
1. Selectyour physiographic /geologic region. (see map on 'instructions' page)
2. Enterthe area of the entire development in square feet (ft').
3. Select the location that is most representative of the site's precipitation characteristics. (see map on 'instructions' page)
4. For each applicable land use, enter the total area of that land use that lies within the development under pre - development conditions.
5. For each applicable land use, enterthe total area of that land use that lies within the development under post - development conditions, before BMP implementation.
6. Ensure that the sum of pre- and post - development areas entered equal the orginaI development area.
7. Continue to "BMP Characteristics'' tab.
Additional Guidelines
- For non - residential watersheds, indicate acreages of each land use type in Column 1 for both pre- and post - development conditions.
- For residential watersheds, complete the required information in Column 2 for both pre- and post- development conditions.
- If a given land use is not present in the given watershed, leave the cell blank or enter a zero.
- Ensure that land use areas entered for both pre- and post - development conditions match the total development area entered in cell 021.
- Residential areas may be entered by average lot size (column, part A), or may be separated into individual land uses (column 2, part B) - do NOT list out individual land uses within an
area already described by lot size.
- Unless runoff flowing onto the development from offsite is routed separately around orthrough the site, the offsite catchment area draining in must be included in the acreage
values of the appropriate land use(s) and treated.
Physiographic /Geologic Region:
Triassic Basin
Soil Hydrologic Group
D
Precipitation location:
Raleigh
COLUMN 1 -- NON- RESIDENTIAL LAND USES
1,508,855
Development Name:
Pre-
TP EMC Development
(mg /L) (ftz )
Model Prepared By:
TN EMC
(r ng/L)
P o
Development
(ft')
COMMERCIAL
Parking lot
1.44
1 0.16
-ac lots
Roof
1.08
1 0.15
Open /Landscaped
2.24
0.44
INDUSTRIAL
Parking lot
1.44
0.39
1 -ac lots
Roof
1.08
0.15
Open /Landscaped
2.24
0.44
TRANSPORTATION
Hi h Densi interstate, main
3.67
0.43
Multi- family
Low Densi ,econda ,feeder
1.4
0.52
Rural
1.14
0.47
Sidewalk
1.4
1.16
PERVIOUS
Managed pervious
3.06
0.59
PART B
Unmanaged (pasture)
3.61
1.56
0.52 37,824
118,730
Forest
1.47
0.25
1.44
0.39
JURISDICTIONAL LANDS*
Parking lot
1.44
Natural wetland
Roof
Riparian buffer
0.15 25,323
280,000
Sidewalk /Patio
Open water
1.4
1.16
23,750
LAND TAKEN UP BY BMPs
1.08
0.15
0.44
0.59 599,318
482,285
*Jurisdictional land uses are not Included In nutrient /flow calculations.
Total Development Area (ft'):
1,508,855
Development Name:
Indian Wells
Model Prepared By:
MAR
COLUMN 2 -- RESIDENTIAL LAND USES
Custom Pre- Post -
Lot Size Age TN EMC TP EMC Development Development
(ac) (yrs) (mg /L) (mg /L) (ft2) ft)
PART A
-ac lots
-ac lots
-ac lots
1 -ac lots
2 -ac lots
Multi- family
Townhomes
Custom Lot Size
PART B
Roadway
1.4
0.52 37,824
118,730
Driveway
1.0
1.44
0.39
Parking lot
1.44
0.39
Roof
1.08
0.15 25,323
280,000
Sidewalk /Patio
1.4
1.16
23,750
Lawn
2.24
0.44
0.59 599,318
482,285
Managed pervious
3.06
Forest
1.47
0.25 846,390
579,930
Natural wetland*
Riparian buffer*
Ell
Open water*
LANDTAKEN UP BY BMP, 1.08 0.15 24,160
Total Development Area Entered (ft): 1,508,855
Total Pre - Development Calculated Area (ft): 1,508,855
Total Post - Development Calculated Area (ft): 1,508,855

BMP CharacteristicsVer2.0 Return to Watershed Proceed to Development
Clear All Values Re—to Instructions Characteristics Summery J
InstruRions
1. Selectthe type of BMP for each catchment.
2. Enter the area of each land use type m the contributing drainage area for each BMP.
3. Continue to "Development Summary" tab.
Additional Guidelines
This spreadsheet allows the development to be divided into as many as 6 smaller catchments.
- BMPS 1, 2, and 3 fora given catchment are assumed to operate m series, with the outflow from 1 serving as the inflow to 2, etc.
- If the outflow from an entire catchment (including outflow from selected BMPS) drains to another BMP, indicate this m the drop down menu below the BMP type and leave all cells for individual land uses blank.
- Not all BMP or catchments must be utilized. Simply leave fields blank in the columns not needed.
- Leave cells blank or insert zeroes if a land use is not present m the area draining to the BMP.
-FOr water harvesting BMPS, be sure to enter the per cent volume reduction that will be achieved by your system. Volume detention(catch- and - release mechanisms) will not be considered -Only proven volumer.d.cti.m are valid i nputs.
-The BMP undersi mig option should only be used for existing development orretrofit sites.
- Volume reduction efficiencies for undersized BM Ps are calculated based c n a 1:1 ratio (a BMP that is 60 %smaller than the required design size is assigned a removal efficiency equal to 60 % of the standard efficiency
value). Effluent concentrations remain the same as full -sized BMPS.
- IMPORTANT: for the land area calculation checks to occur, you MUST press enter after entering a value for area to be treated by a BMP (not just click c n the next cell).
- See User's Manual for instructions c n modeling oversized BM Ps
BMP DETAILS
BMP
Volume ReduRion ( %)
TN Effluent Concen.
(mg/L)
TP Effluent Concen.
(MI
BiorMention with IWS
35%
0.95
0.12
BiorMention without IWS
15%
1.00
0.12
Dry Detention Pond
0%
1.20
0.20
Grassed Swale
0%
1.21
0.26
Green ROOF
50%
1.08
0.15
Level Spreader, Filter Strip
20%
1.20
0.15
Permeable Pavement•
0%
1.44
0.39
Sand Fite,
S%
0.92
0.14
Water Harvesting
s er defined
1.08
0.15
Wet Detention Pond
5%
1 1.01
0.11
Wetland
15%
1 1.08
0.12
n treating commercial parking lot, INemuent concentration= u.ib mg /c
Type of IBMIP:
—I d.cti.n in decimal form.
C.tchm.rt 1:
Utchm.rt 3:
Ford Filter Strip
Does IBMIP accept the ou
no
Detention L-e Spread
P nd Filt r St rip
Ford Filter Strip
If so, indicate which one(s). (Land se areas entered below are in aM the watershed areas treated
n.InoIno noI
by conicrib�lhmer,I
no
no
no
no
no
�I
no
�I no
Utchm.rt 4:
Utchm.rt 5:
IL Utchm.rt 6:
F Drainage Are. Land Use
Are. Treated
byBMP
Are. treated Are. treated
by IBIMP #3 that is rot
treated by IBIMP #1 treated by 1 #1
A... T ... t d
B
Area treated
treated by IBIMP #1
Aie. t ... t.cl
Are, t ... t,d 1 11 IBIMP #3 that is rot
Are, Treated
V IBIMP treated by IBIMP #1 treated by 1 #1
Are. Treated
by IBIMP
AP, T ... t d
, IBIMP
A... t ... t,d
IBIMP . that is rot
e.ted by 1 #1
Are. Treated
by IBIMP
All I
Allow
Us:" Total Land
A, —be
Treated Based on
392,733 0
0
0
0
0

Date:
WATERSHED SUMMARY Ver2.0
3. Development Summary
REGION:
Triassic Basin
TOTAL DEVELOPMENT AREA (ft!):
1,508,855
Percent Impervious (%)
25%
25%
0%
Pre - Development Conditions
Post - Development Conditions
Post - Development w/ BMPS
Percent Impervious
4.2%
29.6%
29.6%
N
Total Nitrogen Loading (lb /ac /yr)
168%
96%
Annual Runoff Volume
Total Phosphorus EMC (mg /L)
-18%
-58%
-49%
500,551
1,806,632
1,403,947
Total Nitrogen EMC
Grassed Swale
0%
1.21
(mg /L)
1.74
1.29
1.22
Total Nitrogen Loading
Level Spdr, Filter
20%
1.20
(lb /ac /yr)
1.57
4.22
3.07
Total Phosphorus EMC
Permeable
Pond
(mg /L)
0.38
0.31
0.16
Total Phosphorus Loading
Sand Filter
5%
0.92
(lb /ac /yr)
0.34
1.02
0.41
Percent Difference Between:
'IVegative percent dltterence values Indicate a decrease In runottvolume, pollutant concentration or pollutant loading. Positive values Indicate an Increase.
BMP SUMMARY Ver2.0
Indian Wells
MAR
July 9, 2014
BMP VOLUME REDUCTIONS /EFFLUENT CONCENTRATIONS
Pre -Dev. &
Post -Dev. without BMPs
Pre - Development &
Post - Development with BMPs
Post -Dev without BMPS &
Post -Dev with BMPS
Percent Impervious (%)
25%
25%
0%
Annual Runoff Volume (c.f.)
261%
180%
-22%
Total Nitrogen EMC (mg /L)
-26%
-30%
-6%
Total Nitrogen Loading (lb /ac /yr)
168%
96%
-27%
Total Phosphorus EMC (mg /L)
-18%
-58%
-49%
Total Phosphorus Loading (Ib/ac)
196%
18%
-60%
'IVegative percent dltterence values Indicate a decrease In runottvolume, pollutant concentration or pollutant loading. Positive values Indicate an Increase.
BMP SUMMARY Ver2.0
Indian Wells
MAR
July 9, 2014
BMP VOLUME REDUCTIONS /EFFLUENT CONCENTRATIONS
'It treating commercial parking lot, I P effluent concentration - U.l6 mg /L
IReturn to Instructions
IReturn to Watershed Characteristics i
IReturn to BMP Characteristics
IPrint Summary i
T lume Reduction
TN Effluent Cancer.
TP Effluent Cancer.
CATCHMENT 4
%)
(mg /L)
(mg /L)
Bioretention with
35%
0.95
0.12
WS
BMP1
BMP2
BMP3
Bioretention without
15%
1.00
0.12
MIS
BMP3
BMP1
BMP2
Dry Detention Pond
0%
1.20
0.20
Grassed Swale
0%
1.21
0.26
Green Roof
50%
1.08
0.15
Level Spdr, Filter
20%
1.20
0.15
Strip
--
Catchment Outflow
Permeable
Pond
Filter Strip
Pavement*
0%
1.44
0.39
Sand Filter
5%
0.92
0.14
Water Harvesting
user defined
1.08
0.15
Wet Detention Pond
5%
1.01
0.11
Wetland
15%
1.08
0.12
'It treating commercial parking lot, I P effluent concentration - U.l6 mg /L
IReturn to Instructions
IReturn to Watershed Characteristics i
IReturn to BMP Characteristics
IPrint Summary i
BMP Outflow
3.61 3.28 -- 6.30 5.79 -- 5.53 5.07 -- -- -- -- -- -- -- -- -- --
Nitrogen (Ibs /ac /yr)
BMP Outflow
Phosphorus (Ibs /ac /yr) '
Catchment Outflow Nitrogen EMC (mg /L)
CATCHMENT 1
CATCHMENT 2
CATCHMENT 3
CATCHMENT 4
CATCHMENT 5
CATCHMENT 6
BMP1
BMP2
BMP3
BMP1
BMP2
BMP3
BMP1
BMP2
BMP3
BMP1
BMP2
BMP3
BMP1
BMP2
BMP3
BMP1
BMP2
BMP3
--
Wet Detention
Level Spreader,
Catchment Outflow Phosphorus EMC
Wet Detention
Level Spreader,
Level Spreader,
(mg/L)
0.152
0.152
0.152
--
--
--
Catchment Outflow
Pond
Filter Strip
-
Pond
Filter Strip
--
Wet Detention Pond
Filter Strip
--
--
--
--
--
--
--
--
--
--
Total Area Treated
(ac)
9.12
9.12
--
9.02
9.02
--
2.64
2.64
--
--
--
--
--
--
--
--
--
--
Total Inflow Volume
531,665
505,082
--
927,384
881,015
--
237,851
225,958
--
--
--
--
--
--
--
--
--
--
Percent Volume Reduced
5%
20%
--
5%
20%
--
5%
20%
--
--
--
--
--
--
--
--
--
--
Inflow Nitrogen EMC
(mg /L)
1.35
1.01
--
1.24
1.01
--
1.26
1.01
--
--
--
--
--
--
--
--
--
--
Total Inflow Nitrogen
(Ib /ac /yr)
4.90
3.61
--
7.98
6.30
--
7.10
5.53
--
--
--
--
--
--
--
--
--
--
Inflow Phosphorus EMC
(mg /L)
0.305
0.115
--
0.321
0.115
--
0.322
0.115
--
--
--
--
--
--
--
--
--
--
Total Inflow Phosphorus
(Ib /ac )
1.11
0.46
--
2.06
0.82
--
1.81
0.72
--
--
--
--
--
--
--
--
--
--
BMP Outflow
3.61 3.28 -- 6.30 5.79 -- 5.53 5.07 -- -- -- -- -- -- -- -- -- --
Nitrogen (Ibs /ac /yr)
BMP Outflow
Phosphorus (Ibs /ac /yr) '
Catchment Outflow Nitrogen EMC (mg /L)
1.19
1.19
1.19
--
--
--
Catchment Outflow
Total Nitrogen (Ib/ac )
3.28
5.79
5.07
--
--
--
Percent Reduction in Nitrogen Load ( %)
23%
19%
20%
--
--
--
Catchment Outflow Phosphorus EMC
(mg/L)
0.152
0.152
0.152
--
--
--
Catchment Outflow
Total Phosphorus(lb /ac /yr)
0.419
0.738
0.647
--
--
--
Percent Reduction in Phosphorus Load ( %)
47%
10%
49%
--
--
--

Jordan Lake Developer Nutrient Reporting Form
Please complete and submit the following information to the local government permitting your development project to
characterize it and assess the need to purchase nutrient offsets. Contact and rule implementation information can be
found online at http: / /Dortal.ncdenr.org/ web /wo /os /nos /nutrientoffsetintro.
PROJECT INFORMATION (for Jordan Cake)
Applicant Name:
S T141L K Aw, .a L,1-2- fE N T
Project Name:
N 6 tar V I S
Project Address (if available): Street: City/Town: County:
11)0 r 04n01 lu& G-otr (A,.4-yLfG
Date: (mo/d/yr)
Project
Lat: (decimal degrees)
Long: (decimal degrees)
_70- 4-
Location :
Is this Redevelopment? ❑ Yes
No
Development Type (Please check all that apply)
Impervious Cover
Commercial
�ixed
-Use
Single Fam. Residential
(Pre- Construction)
4.7-
❑
❑
Industrial
Institutional
I —
❑
Duplex Residential
❑'
Multi -Fam. Residential
Impervious Cover ( °k):
(Post - Construction)
Z9 • Ce
JORDAN WATERSHED INFORMATION
Small Watershed ID (6 digits): (See next page or online mao.)
New Development Load Requirements (See individual rules
D (_ 0 / q0
for a full description of nutrient requirements.)
Jordan Subwatershed (Please check one)
Loading Rate Targets
Nitrogen N & Phosphorus (P
Offsite Thresholds
6 N Ibs /ac Residential;
Upper New Hope
2.2 N Ib /ac /yr
10 N Ibs /ac Commercial
0.82 P Ib /ac /yr
(must meet all onsite treatment
requirements)
❑
Lower New Hope
4.4 N Ib /ac/yr
0.78 P Ib /ac /yr
NUTRIENT
OFFSET REQUEST(Must meet the offsite thresholds - see above)
Nitrogen Loading / Offset Needs
(A)
(B)
(C)
(D)
(E)
(F)
I (G)
(H)
Untreated
Treated
Loading Rate
Reduction Need
Project
Offset
Delivery
State Buy Down
Loading Rate
Loading Rate
Target
(lbslaclyr)
Size (ac)
Duration (yrs)
Factor ( °h)
Amount (Ibs)
(Ibslactyr)
(lbslac/yr)
(lbstac/yr)
B- C
D' E` F' G
4.7.7-
3.07
2-.2
0 .g?
sf.2
30
0
7579.-7
Phosphorus Loading 1 Offset Needs
(A) (B) (C) (D) (E) (F) (G) (H)
Untreated Treated Loading Rate Reduction Need Project Offset Delivery State Buy Down
Load Rate Load Rate Target (lbslaclyr) Size (ac) Duration (yrs) Factor(96) Amount (Ibs)
(lbslaclyr) (lbslaclyr) (lbsiac/yr) B - C D ' E' F ' G
o• 3 4
0. 41
o. S2
0
;4. z
30
a
Control of Peak Stormwater Flow (1 year 24 hour design storm)
Calculated Predevelopment Peak Flow
SS 0 , If
Calculated Post Development Peak Flow
614 . f
F ow Control Method
W I`T- P
Authorizing Local Government Name:
Staff Name:
Staff Email:
Phone:
Jordan Nutrient Load Reporting Form. September 12, 2012

APPENDIX D
PIPE SIZING, GUTTER SPREAD, & HGL CALCULATIONS

1
1®
Notes
HGL is dependent on tailwater from BAAP; Pipe is o-ring gasketed w/ joints double wrapped in no—oven fi I ter fabc
2 'Upstream structure shal I be single piece pre- cast, fitted with A Lock neoprene gaskets cast into manhole wal
'Inlet shal I have 2 1 coal depression.
Intensity show in this table is based on a time of concentration �c) of 5 minutes
'Al RCP pipe is Class III unless otheriwse noted.
'Gutter spread shown in this table is based on the 2 yr storm intensity (4.00 inkhr)
'Yard Inlet (YI) rim elev is @ top of grate.
Flared End Section (FE)

CULVERT SUMMARY
Project Name Indian Wells Subdivisic
Bohler Project # NCR142011
Drainage Area (Ac.)
127.0
Design Frequency (yr.)
25
Design Discharge (cfs)
550.60
Design H.W. Elevation (ft.)
303.48
Q100 Discharge (cfs)
710.50
Q100 H.W. Elevation (ft.)
306.01
12'X 6' Upstream Invert (ft.)
295.40
12'X 6' Downstream Invert (ft.)i
1 291.60
Note: The culvert configuration is a12' x 6' RC Box Culvert
130 LF @ 2.92 % located in the channel with a 1' bury for
aquatic passage. The roadway does NOT overtop in the 100 -
year storm.

APPENDIX E
DISSIPATOR SIZING CALCULATIONS

DISSIPATOR SUMMARY
Indian Wells Subdivision
Bohler Project # NCR142011
LOCATION
PIPE SIZE
START WIDTH
END WIDTH
APRON LENGTH
STONE CLASS
THICKNESS
FE 100
30"
7.5'
10.5'
8'
B
15"
FE 150
30"
7.5'
10.5'
8'
B
15"
BMP #1 OUTLET
15"
3.8'
13.3'
12'
B
15"
FE 200
18"
4.5'
9.5'
8'
B
15"
FE 250
30"
7.5'
10.5'
8'
B
15"
BMP #2 OULET
15"
3.8'
13.3'
12'
B
15"
FE 300
36"
9.0'
31.0'
12'
B
18"
BMP #1 OUTLET
15"
3.8'
13.3'
12'
B
15"
ALL RIP -RAP DISSIPATORS SHALL BE UNDERLINED WITH FILTER FABRIC PER A GEOTECHNICAL ENGINEER'S RECCOMENDATION.

User Input Data
Calculated Value
Reference Data
Designed By: LML Date: 2014.05.08
Checked By:
Company: Bohler Engineering NC
Project Name: Indian Wells Subdivision
Project No.: NCR 142011
Site Location (City /Town) Cary
Culvert Id. BMP 1 Outlet
Total Drainage Area (acres) NA
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the tailwater depth is less
than half the outlet pipe diameter, it is classified minimum tailwater condition.
If it is greater than half the pipe diameter_ it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a minimum tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum /Maximum tailwater?
Discharge (cfs)
Velocity (ft. /s)
15
0
Min TW (Fig. 8.06a)
0.7
10.9
Step 2. Based on the tailwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d50 riprap size and minimLUn apron length
(Q. The d50 size is the median stone size in a well- graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2_
Riprap d50, (ft.)
Minimum apron length, La (ft.)
Apron width at pipe outlet (ft.)
Apron shape
Minimum TW Maximum TW
Figure 8.06a Figure 8.06b
0.6
12
3.75 3.75
Trapezoid

Apron width at outlet end (ft.) 13.25 1.25
Step d. Determine the maximum stone diameter
dm,x = 1.5 x d5,
Minimum TW
Max Stone Diameter, dmax (ft.) 0.9
Step 5. Deternne the apron thickness -
Apron thickness =
Apron Thickness(ft.)
Minimum TW
1.35
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making it level for the nnirnilnnrm
length, La_ from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured_ Beep the
apron as straight as possible and align it with the flogs of the receiving streainn.
Make any necessan• ahgiunent bends near the pipe outlet so that the entrance
into the receiving stream is straight.
Some locations may • require lining of the entire channel cross section to assure
stabihty.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessan (Appeildix 5.05). NNliere overfills exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8.06.8.

Figure 8.06a: Design of outlet protection from a round pipe flowing full,
minimum tailwater condition (Tw<0.5 diameter)
4
3
Q
2 N
a
a
1 v
a.�
a
totO
Curves may not be extrapolated
Figure 8.06& Design of outlet protecfton protection Mom a round pipe flowtn0 lull. niournurn Ltdwater condition (T. c 0.5 dameter)
1$ r I e_,,p @ 2 0 7 '7e
0,-7 c.fs e 10,) Fr'S
V 5 e I Z L.-" w( J-5.0= t: I b — V S+s ,t.t►'� = ''S tr►1 i N
R.er. 11.4503 5.063
t
Outlet
W 00 a
t
pipe
diameter
..
LA
0. 5DO
�,.
•
60
r ldlt�
.iiN
P�rlll4
t
•
,tl��IPN
rl �rtii�lln
rary
I Ian
11q
9
•:
�
IUrN
�r
I
:Pr
jplINU
'
{ItIlIlNlt
!I
I
1
,
�
r
I�Mi�n�µnH��
i
•..
i
MEN
AEI
4
3
Q
2 N
a
a
1 v
a.�
a
totO
Curves may not be extrapolated
Figure 8.06& Design of outlet protecfton protection Mom a round pipe flowtn0 lull. niournurn Ltdwater condition (T. c 0.5 dameter)
1$ r I e_,,p @ 2 0 7 '7e
0,-7 c.fs e 10,) Fr'S
V 5 e I Z L.-" w( J-5.0= t: I b — V S+s ,t.t►'� = ''S tr►1 i N
R.er. 11.4503 5.063

User Input Data
Calculated Value
Reference Data
Designed By: LML Date: 2014.05.08
Checked By:
Company: Bohler Engineering NC
Project Name: Indian Wells Subdivision
Project No.: NCR 142011
Site Location (City /Town) Cary
Culvert Id. BMP 2 Outlet
Total Drainage Area (acres) NA
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the tailwater depth is less
than half the outlet pipe diameter, it is classified minimum tailwater condition.
If it is greater than half the pipe diameter_ it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a minimum tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum /Maximum tailwater?
Discharge (cfs)
Velocity (ft. /s)
15
0
Min TW (Fig. 8.06a)
0.5
11.6
Step 2. Based on the tailwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d50 riprap size and minimLUn apron length
(Q. The d50 size is the median stone size in a well- graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2_
Riprap d50, (ft.)
Minimum apron length, La (ft.)
Apron width at pipe outlet (ft.)
Apron shape
Minimum TW Maximum TW
Figure 8.06a Figure 8.06b
0.6
12
3.75 3.75
Trapezoid

Apron width at outlet end (ft.) 13.25 1.25
Step d. Determine the maximum stone diameter
dm,x = 1.5 x d5,
Minimum TW
Max Stone Diameter, dmax (ft.) 0.9
Step 5. Deternne the apron thickness -
Apron thickness =
Apron Thickness(ft.)
Minimum TW
1.35
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making it level for the nnirnilnnrm
length, La_ from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured_ Beep the
apron as straight as possible and align it with the flogs of the receiving streainn.
Make any necessan• ahgiunent bends near the pipe outlet so that the entrance
into the receiving stream is straight.
Some locations may • require lining of the entire channel cross section to assure
stabihty.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessan (Appeildix 5.05). NNliere overfills exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8.06.8.

15 OAP T
Figure 8.06a: Design of outlet protection from a round pipe flowing full,
minimum tailwater condition (Tw<0.5 diameter)
1
III ,,II
111 � k 1
, 1 IIIY 1 ',.��� � • ���j Y
1 Ildln NNI • � r��� • W
„11111 +1����Afff
g1III Y I 1 !' �et,I II IIY
ff I� ■IIY.�1� .I�.JNI� .+� II IIM
N Unlltllll - ! Ir IN 1 IW
'� 11� ��1 ■111,
I 11 11 111
Discharge (Olsec)
Curves may not be extrapolated.
Figure 8.06a Design of outlet proWaxon ptotecbon from a round pipe flowing lull, muurnum tallwator condition (T„ c 05 diameter)
S ,t P- CP (2- 2.33io
O.Sc�s (r Il.lo t=1':
USrL IZI t0n.a so` S1 --� VSfc C Sb w,IN,
Raw, L 93 8.06.3

User Input Data
Calculated Value
Reference Data
Designed By: LML Date: 2014.05.08
Checked By:
Company: Bohler Engineering NC
Project Name: Indian Wells Subdivision
Project No.: NCR 142011
Site Location (City /Town) Cary
Culvert Id. FE 100
Total Drainage Area (acres) NA
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the tailwater depth is less
than half the outlet pipe diameter, it is classified minimum tailwater condition.
If it is greater than half the pipe diameter_ it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a minimum tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum /Maximum tailwater?
Discharge (cfs)
Velocity (ft. /s)
30
0
Min TW (Fig. 8.06a)
20.2
2.6
Step 2. Based on the tailwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d50 riprap size and minimLUn apron length
(Q. The d50 size is the median stone size in a well- graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2_
Riprap d50, (ft.)
Minimum apron length, La (ft.)
Apron width at pipe outlet (ft.)
Apron shape
Minimum TW Maximum TW
Figure 8.06a Figure 8.06b
0.6
8
7.5 7.5
Trapezoid

Apron width at outlet end (ft.) 10.5 2.5
Step d. Determine the maximum stone diameter_
dm,x = 1.5 x d5,
Minimum TW
Max Stone Diameter, dmax (ft.) 0.9
Step 5. Deternne the apron thickness -
Apron thickness =
Apron Thickness(ft.)
Minimum TW
1.35
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making it level for the nnirnilnnrm
length, La_ from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured_ Beep the
apron as straight as possible and align it with the flogs of the receiving streainn.
Make any necessan• ahgiunent bends near the pipe outlet so that the entrance
into the receiving stream is straight.
Some locations may • require lining of the entire channel cross section to assure
stabihty.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessan (Appeildix 5.05). NNliere overfills exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8.06.8.

Figure 8.86a: Design of outlet protection from a round pipe flowing full,
minimum tailwater condition (Tw<0.5 diameter)
1
-5111,.11{
t�uulflN
I � � liin uutll Itt
• N
./� ,Alit
K I nl n,•rrr
W Ingo
j1t1���Irru �
pfhll
1 ' ��;r •� I'll , III
r�l
nnln 1
1 III II41r fl IIMIIIIM M�.�1.�1M� M'
U4tt I11 I I�I�I'I�I' I •v'�
�� 1 Illflr 1
s" i I1111 it :�F,• I
p .I Fit WIN �•a. ml �
NI� �IIIIIIIIIIII � Jvttal
1 hl 11 I1 t141t IIHtl lltll ♦ � ttl" -. NIM
1 I
II�
P!F ^ �• III&
-� •� .M.Ij{f �/h�,IG.�i�N 1111 ll 111 lltl
• � ,11� unli
Curves may not be extrapolated
Figure 8.06& Dosrgn of outk,t protea.on protection Iron a round pipe flowing full, mn.mum tallwater condition (T,,,, .c 0.5 dameler)
So" 2cp @ o. /0%
2a.Z IFS @ 2.to FPS —* Pill IS Sv6wFrt1.c;4
USk 81 L���. Gam► � r>
Rex-. 12 93 8.063

User Input Data
Calculated Value
Reference Data
Designed By: LML Date: 2014.05.08
Checked By:
Company: Bohler Engineering NC
Project Name: Indian Wells Subdivision
Project No.: NCR 142011
Site Location (City /Town) Cary
Culvert Id. FE 150
Total Drainage Area (acres) NA
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the tailwater depth is less
than half the outlet pipe diameter, it is classified minimum tailwater condition.
If it is greater than half the pipe diameter_ it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a minimum tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum /Maximum tailwater?
Discharge (cfs)
Velocity (ft. /s)
30
0
Min TW (Fig. 8.06a)
22.1
18.3
Step 2. Based on the tailwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d50 riprap size and minimLUn apron length
(Q. The d50 size is the median stone size in a well- graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2_
Riprap d50, (ft.)
Minimum apron length, La (ft.)
Apron width at pipe outlet (ft.)
Apron shape
Minimum TW Maximum TW
Figure 8.06a Figure 8.06b
0.6
8
7.5 7.5
Trapezoid

Apron width at outlet end (ft.) 10.5 2.5
Step d. Determine the maximum stone diameter_
dm,x = 1.5 x d5,
Minimum TW
Max Stone Diameter, dmax (ft.) 0.9
Step 5. Deternne the apron thickness -
Apron thickness =
Apron Thickness(ft.)
Minimum TW
1.35
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making it level for the nnirnilnnrm
length, La_ from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured_ Beep the
apron as straight as possible and align it with the flogs of the receiving streainn.
Make any necessan• ahgiunent bends near the pipe outlet so that the entrance
into the receiving stream is straight.
Some locations may • require lining of the entire channel cross section to assure
stabihty.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessan (Appeildix 5.05). NNliere overfills exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8.06.8.

Figure 8.06a: Design of outlet protection from a round pipe flowing full,
minimum tailwater condition (Tw<0.5 diameter)
/
• 1. •1
�I1/
Milo
�1' t� IIYIIIN
1' I
110110 ph
.1 I}! IIIN
tll 4 1 I'.N
1} If1�41Mq U11111 It �� w.
11 Ililll .. nrr � 1 Jr..
It
rlri..1 « r
�_I1 /�,11II I M1IEEp {N���11++1p ~ t
, B 111 1 1 i 1111 Il lltliilll'MW
f r
I Vta IOM11n
�1 11n 1 nfunnN
111 fl tin No I�{�
Ipp} 111111 rML .
1111 ` (N I UYI
It N Irl
Curves may not be extrapolated
Figure 8.06a Design of ouriet protertron protection 11om a round pipe flowing full. minimum to lwater conchtlon (T,. < 0 5 damelefr
3d'1 & LIO
22.1 cK 1 �, >�+s —� P•�� is SvFSw.ri n cIG+�
�JSZ B" lo+JCn G1 �`SS 3
Fev.1! 193 8.06.3

User Input Data
Calculated Value
Reference Data
Designed By: LML Date: 2014.05.08
Checked By:
Company: Bohler Engineering NC
Project Name: Indian Wells Subdivision
Project No.: NCR 142011
Site Location (City /Town) Cary
Culvert Id. FE 200
Total Drainage Area (acres) NA
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the tailwater depth is less
than half the outlet pipe diameter, it is classified minimum tailwater condition.
If it is greater than half the pipe diameter_ it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a minimum tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum /Maximum tailwater?
Discharge (cfs)
Velocity (ft. /s)
18
0
Min TW (Fig. 8.06a)
8.6
21.7
Step 2. Based on the tailwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d50 riprap size and minimLUn apron length
(Q. The d50 size is the median stone size in a well- graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2_
Riprap d50, (ft.)
Minimum apron length, La (ft.)
Apron width at pipe outlet (ft.)
Apron shape
Minimum TW Maximum TW
Figure 8.06a Figure 8.06b
0.6
8
4.5 4.5
Trapezoid

Apron width at outlet end (ft.) 9.5 1.5
Step d. Determine the maximum stone diameter_
dm,x = 1.5 x d5,
Minimum TW Maximum TW
Max Stone Diameter, dmax (ft.) 0.9 0
Step 5. Deternne the apron thickness -
Apron thickness =
Minimum TW Maximum TW
Apron Thickness(ft.) 1.35 0
Step 6. Fit the riprap apron to the site by making it level for the nnirnilnnrm
length, La_ from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured_ Beep the
apron as straight as possible and align it with the flogs of the receiving streainn.
Make any necessan• ahgiunent bends near the pipe outlet so that the entrance
into the receiving stream is straight.
Some locations may • require lining of the entire channel cross section to assure
stabihty.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessan (Appeildix 5.05). NNliere overfills exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8.06.8.

FF zoo
Figure 8.06a: Design of outlet protection from a round pipe flowing full,
minimum tailwater condition (Tw<0.5 diameter)
3 0
Outlet W • Do ' La
pipe 1
drarneter Mo)
a
i w r O.SOa
IPI
t00
dP o
k PQ 60
V0o
50 IM
Discharge (h3 /sec)
N
CD
2 N
Cn
a
1?
II
I O
La
1000
Curves may not be extrapolated.
Figure 8.06a Des+gn of oulUtt protecl*n proWCIoon Irom a round pApe llowing full, m nrmum tadvmwr conditron (T. < 0 5 Oameter)
8" P'o Q, -1 .11 `7,
j?jo r-r5 Q. Z1 FPS r'a 15 Svfsror,W -Wtb
U s &._ 8 r 1,...v (- G -wS s ►3
Kra. 12 93 8.06.3

User Input Data
Calculated Value
Reference Data
Designed By: LML Date: 2014.05.08
Checked By:
Company: Bohler Engineering NC
Project Name: Indian Wells Subdivision
Project No.: NCR 142011
Site Location (City /Town) Cary
Culvert Id. FE 250
Total Drainage Area (acres) NA
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the tailwater depth is less
than half the outlet pipe diameter, it is classified minimum tailwater condition.
If it is greater than half the pipe diameter_ it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a minimum tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum /Maximum tailwater?
Discharge (cfs)
Velocity (ft. /s)
30
0
Min TW (Fig. 8.06a)
0.08
3.69
Step 2. Based on the tailwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d50 riprap size and minimLUn apron length
(Q. The d50 size is the median stone size in a well- graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2_
Riprap d50, (ft.)
Minimum apron length, La (ft.)
Apron width at pipe outlet (ft.)
Apron shape
Minimum TW Maximum TW
Figure 8.06a Figure 8.06b
0.6
8
7.5 7.5
Trapezoid

Apron width at outlet end (ft.) 10.5 2.5
Step d. Determine the maximum stone diameter_
dm,x = 1.5 x d5,
Minimum TW
Max Stone Diameter, dmax (ft.) 0.9
Step 5. Deternne the apron thickness -
Apron thickness =
Apron Thickness(ft.)
Minimum TW
1.35
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making it level for the nnirnilnnrm
length, La_ from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured_ Beep the
apron as straight as possible and align it with the flogs of the receiving streainn.
Make any necessan• ahgiunent bends near the pipe outlet so that the entrance
into the receiving stream is straight.
Some locations may • require lining of the entire channel cross section to assure
stabihty.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessan (Appeildix 5.05). NNliere overfills exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8.06.8.

FE z sp
Figure 8.06a: Design of outlet protection from a round pipe flowing full,
minimum tailwater condition (Tw<0.5 diameter)
r
J�p 1.1' •P
TfB�. •�
t
WIN,
"' p111111 Q I Illtl glll1611 J�• 11��
IsM :I!!'"1!IikII+F�j$jj It+ �� IIIIIgni�Me
IM »Ilii11 "1lll�i�'IHlllflgl IU �• I• '
I puupfl NII Iplgnigw . , .in
» » i glllMki N nA r10
��11 I
ii1133wNl,
Mi1VNll1 I�{ HIM ��'
E
nnI
�IgMI��IMIJ
liI
� 11 1 III
Curves may not be extrapolated.
Figure 8.06a Design of outlet protecbon proter.14011 from a rcur:d pipe flowing lull. miranum talhvatur condition (T.. < 0 S darrmeter)
1 � • —1 e-f: l2— 0 B P S --+■j !'r ►'fi I � iSlw � .., r,�+J�
Us.A. cS'I Gary+ Clr'Sf
Rev. 12 93 8.06.3

User Input Data
Calculated Value
Reference Data
Designed By: LML Date: 2014.05.08
Checked By:
Company: Bohler Engineering NC
Project Name: Indian Wells Subdivision
Project No.: NCR 142011
Site Location (City /Town) Cary
Culvert Id. FE 300
Total Drainage Area (acres) 20
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the tailwater depth is less
than half the outlet pipe diameter, it is classified minimum tailwater condition.
If it is greater than half the pipe diameter_ it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a minimum tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum /Maximum tailwater?
Discharge (cfs)
Velocity (ft. /s)
36
0
Min TW (Fig. 8.06a)
65
20.2
Step 2. Based on the tailwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d50 riprap size and minimLUn apron length
(Q. The d50 size is the median stone size in a well- graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2_
Riprap d50, (ft.)
Minimum apron length, La (ft.)
Apron width at pipe outlet (ft.)
Apron shape
Minimum TW Maximum TW
Figure 8.06a Figure 8.06b
0.6
28
9 9
Trapezoid

Apron width at outlet end (ft.) 31 3
Step d. Determine the maximum stone diameter_
dm,x = 1.5 x d5,
Minimum TW Maximum TW
Max Stone Diameter, dmax (ft.) 0.9 0
Step 5. Deternne the apron thickness -
Apron thickness =
Minimum TW Maximum TW
Apron Thickness(ft.) 1.35 0
Step 6. Fit the riprap apron to the site by making it level for the nnirnilnnrm
length, La_ from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured_ Beep the
apron as straight as possible and align it with the flogs of the receiving streainn.
Make any necessan• ahgiunent bends near the pipe outlet so that the entrance
into the receiving stream is straight.
Some locations may • require lining of the entire channel cross section to assure
stabihty.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessan (Appeildix 5.05). NNliere overfills exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8.06.8.

Ff- 300 \
Figure 8.06a: Design of outlet protection from a round pipe flowing full,
minimum tailwater condition (Tw<0.5 diameter)
■ 1�
r P I
1
e r,•• �,y��1, II INN nm u u NN
1 INBiih � 111 I •�i.�I�i1��,'/I',+� ' � ®�r��
n I h °I1!+ii +u l i t
11Nltllln ...nlnr.'•:. ..� . .Or�'�
�I {II I'tlnuu. .. •' r'l 11 PAIN- • �� ��
IIII�1 °'..nHlt �// �I it�ItlIIIILINM � l�
IIl lllpllltlnn�i��l l�llllt+IN111MIY '� �/
■1I1I1III Ullllltlll 1iYi IMMMMMM 11111UINIYYIIM
1 MIIlIIIII IIIII IIIL 1l11IIIII IItIi IIIY � ,. ���� ��. �/�
NIIII 1 1 UIRn INI Kill N
gllU�l�l,l�,ltlll�� j i�t�`Ntt'InNl
�� �•.Nl� ICIe� t1�1
1
1 1 11 1 111
Curves may not be extrapolated.
Figure 8.06a D"gn of outset protection protectwn Irom a round pipe Ilpwlng full, minimum tallwater comStlon (T. < 0 5 ciamete:ri
1�4L P Ig Z.'52 -2.
2 Z0.2 FPS
USA 7S+' Lv ,,q Gtw•.��
Rev. 1.93 8.06.3

APPENDIX F
ENVIRONMENTAL LETTERS & MAPS

April 23, 2014
Mr. Steven Ball
Soil and Environmental Consultants, PA
8412 Falls of the Neuse Rd, Suite 104
Raleigh, NC 27615
WATER RESOURCES DEPARTMENT
Subject: Jordan Lake Watershed - Urban Transition Buffer Rules
Indian Wells Sites (6 properties)
Real ID #: 0081386, 0084257, 0084064, 0150628, 0084259, and 0084258
(7008, 7016, 7017, 7020, 7029, and 7032 Indian Wells Rd.)
TCRB 14 -010
Dear Mr. Ball:
The site location map and other information that was provided, allowed a determination to be made as
to whether or not the referenced site would require compliance with The Town of Cary Urban Transition
Buffer (UTB) Rules. This project, as referenced by the Town of Cary as TCRB 14 -010, includes
features as depicted on the attached maps. The table below summarizes the stream determinations
made in a site visit on April 14, 2014. This determination is valid until April 14, 2019.
Reference ID
I USGS Ma 100 Ft. Buffer
Soil Survey Ma 50 Ft. Buffer
Not Subject
A
x*
B
x (Start at Flag S02)
C
x*
Pond C
x*
D
x
E
x*
*Feature subjectivity not contested.
Si ly,
1 �44�1
n Patterson
Town of Cary Water Resources Department
TOWN Ot CARY
318 North Academy Street •Cary, NC 27513•PO Box 8005•Cary, NC 27512 -8005
te1919- 469 -4030 • fax [phone] www.townofeary.org

j l� r1 4
- C�RIMMON_Pxwr
,' —��.* � r— .L.J:'�•` � {ter.. ,'! ,\�f
350
J
d .
a
w
,1.
Project No. USGS Vicinity Map I 0 1,000 2,000 4,000
12252.W 1 Feet
Project Mgr.: Indian Wells Site
SB
Wake Co., NC
Scale: •
1" = 1,000' 2013 Green Level USGS Soil & Environmental Consultants, PA
Quadrangle (Portion of
8412 Falls of \clue Road, Suite 104, Raleigh, VC 27615 •Phone: [phone] •Fax: [phone]
2014 -02 -11 Cary Quad also Shown) sandccxom

Project Mgr.:
SB
Indian Wells Site
Wake Co., NC
Scale:
1 " = 500'
1970 Printed Wake County
2014 -02 -11
Soil Survey, Map Sheet 45
8412 Falls of \came Road, Suite 104, Raleigh, NC 27615 • Phone: [phone] • Fax: [phone]
sandec.com

NC Division of Water Quality - Methodology for Identification of Intermittent and
Perennial Streams and Their Origins v. 4.11
NC DWO Stream Identification Form Version 4.11
Date: 3 Z /
Project/Site: -11 !�6
Latitude:
Evaluator:
County: ua
Longitude:
Total Points:
3
2
Stream is at least intermittent /L aj
Stream Dete (circle one)
Other
if 2 19 or perennial If 2 30 7
E hemeral term tte Perennial
p
e. Quad Name:
g•
A. Geomorphology (Subtotal = )
18 Continuity of channel bed and bank
Absent
0
Weak
1
Moderate
Strong
3
2. Sinuosity of channel along thalweg
0
3
2
3
3. In- channel structure: ex. riffle -pool, step -pool,
ripple-pool sequence
0
1
(D2
3
4. Particle size of stream substrate
0
3
2
3
5. Active /relict floodplain
0
2
2
3
6. Depositional bars or benches
0
1
(2
3
7. Recent alluvial deposits
0
0>
2
3
8. Headcuts
0
1
Q
3
9. Grade control
0
0.5
0
1.5
10. Natural valley
0
0.5
0
1.5
11. Second or greater order channel
No 0
Yes = 3
MURU911 aacnes are not raved; see disco ions in manual
B. Hydrology (Subtotal= )
12. Presence of Baseflow
0
1
3
13. Iron oxidizing bacteria
0
3
3
14. Leaf litter
1.5
20. Macrobenthos (note diversity and abundance)
0.5
0
15. Sediment on plants or debris
0
3
1
1.5
16. Organic debris lines or piles
0
2
1
1.5
17. Soil -based evidence of high water table?
No = 0
Yes -
C. 1510109y (Subtotal = .c. )
18. Fibrous roots in streambed
3
1
0
19. Rooted upland plants in streambed
3
1
0
20. Macrobenthos (note diversity and abundance)
2
3
21. Aquatic Mollusks
1
2
3
22. Fish
0.5
1
1.5
23. Crayfish
0
0>
1
1.5
24. Amphibians
0
Q
1
1.5
25. Algae
0
01)
1
1.5
26. Wetland plants in streambed
FACW = 0.75; OBL = 1.5
Other
'perennial streams may also be identfed using other methods. See p. 35 of manual.
Notes:
Sketch:
41

�14dluu Pt"ILP)
NC Division of Water Quality - Methodology for Identification of Intermittent and
Perennial Streams and Their Origins v. 4.11
NC DWO Stream Identification Form Version 4.11
Date: 7 I
Project/Site: �i/tR `
Latitude:
Evaluator:
County: f%
Longitude:
Total Points:
1
2
Stream is at least intermittent
St Determination (circle one)
Other
if s i9 or rennia! if t 30`
p hem I Intermittent Perennial
e. Quad Name:
9•
A. Geomorphology (subtotal=
18 Continuity of channel bed and bank
Absent
0
Weak
1
Moderate
2
Strong
3
2. Sinuosity of channel along thalweg
19. Rooted upland plants in streambed
1
2
3
3. In- channel structure: ex. riffle -pool, step -pool,
ripple-pool sequence
1.5
1
2
3
4. Particle size of stream substrate
m
1
2
3
5. Active /relict floodplain
W
1
2
3
6. Depositional bars or benches
0
Yes = 3
2
3
7. Recent alluvial deposits
1
2
3
8. Headcuts
&
1
2
3
9. Grade control
1.5
0.5
1
1.5
10. Natural valley
0 1
0.5
1
11. Second or greater order channel
No
Yes = 3
niuncarai UILUMs are not raiea; see aiscu ons in manual
B. Hvdrology (Subtotal = 1- 1
12. Presence of Baseflow
(i�
1
2
3
13. Iron oxidizing bacteria
19. Rooted upland plants in streambed
1
2
3
14. Leaf litter
1.5
1
0
15. Sediment on plants or debris
0
3
1
1.5
16. Organic debris lines or piles
0
2
1
1.5
17. Soil -based evidence of high water table?
No
Yes = 3
C. Blol Subtotal =
Ib-
18. Fibrous roots in streambed
3
2
0
19. Rooted upland plants in streambed
3
2
0
20. Macrobenthos (note diversity and abundance)
1
2
3
21. Aquatic Mollusks
1
2
3
22. Fish
0.5
1
1.5
23. Crayfish
0.5
1
1 1.5
24. Amphibians
0
0.5
1
1.5
25. Algae
0
0.5
1
1.5
26. Wetland plants in streambed
FACW = 0.75; OBL = 1.5
Other
`perennial streams may also be identified using other methods. See p. 35 of manual.
Notes:
Sketch:
41

APPENDIX G
O & M MANUALS

WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT — BMP #1
INDIAN WELLS SUBDIVISION
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays, and the
vegetated filter if one is provided.
Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the orifice of any obstructions to ensure that drawdown of the temporary pool occurs
within 2 to 5 days as designed.
2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi - annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
(i.e. stockpiling near a wet detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
BASIN DIAGRAM
Permanent Pool Elevation 308.50
Sediment Removal El. 305.00 7
------- - - - - -- - Sediment Removal Elevation 305.00 75%
Bottom E�vat i on 304.00 5% ------------------------ - - - - -- - - - --
FOREBAY MAIN POND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
7. All components of the wet detention basin system shall be maintained in good working order.
8. Level spreaders or other structures that provide diffuse flow shall be maintained every six months. All
accumulated sediment and debris shall be removed from the structure, and a level elevation shall be
maintained across the entire flow spreading structure. Any down gradient erosion must be repaired and /or
replanted as necessary.
Page 1 of 2

I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify the Town of Cary of any problems with the system or
prior to any changes to the system or responsible party.
Print name:
Title:
Address:
Phone:
Signature:
Date:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the
lots have been sold and a resident of the subdivision has been named the president.
I, , a Notary Public for the State of
County of
, do hereby certify that
personally appeared before me this day of , and acknowledge the due
execution of the forgoing wet [wetland] detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires
Page 2 of 2

WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT — BMP #2
INDIAN WELLS SUBDIVISION
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays, and the
vegetated filter if one is provided.
Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the orifice of any obstructions to ensure that drawdown of the temporary pool occurs
within 2 to 5 days as designed.
2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi - annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
(i.e. stockpiling near a wet detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
BASIN DIAGRAM
Permanent Pool Elevation 310.50
Sediment Removal El. 307.00 7
------- - - - - -- - Sediment Removal Elevation 307.00 75%
Bottom E�vat i on 306.00 5% ------------------------ - - - - -- - - - --
FOREBAY MAIN POND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
7. All components of the wet detention basin system shall be maintained in good working order.
8. Level spreaders or other structures that provide diffuse flow shall be maintained every six months. All
accumulated sediment and debris shall be removed from the structure, and a level elevation shall be
maintained across the entire flow spreading structure. Any down gradient erosion must be repaired and /or
replanted as necessary.
Page 1 of 2

I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify the Town of Cary of any problems with the system or
prior to any changes to the system or responsible party.
Print name:
Title:
Address:
Phone:
Signature:
Date:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the
lots have been sold and a resident of the subdivision has been named the president.
I, , a Notary Public for the State of
County of
, do hereby certify that
personally appeared before me this day of , and acknowledge the due
execution of the forgoing wet [wetland] detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires
Page 2 of 2

WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT — BMP #3
INDIAN WELLS SUBDIVISION
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays, and the
vegetated filter if one is provided.
Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the orifice of any obstructions to ensure that drawdown of the temporary pool occurs
within 2 to 5 days as designed.
2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi - annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
(i.e. stockpiling near a wet detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
BASIN DIAGRAM
Permanent Pool Elevation 321.50
Sediment moval El. 318.7 7 /o
Sediment Removal Elevation 318.00 175%-
Bottom E ------------ vation 317.75 5% ---------------------- ------- -
- - - --
FOREBAY MAIN POND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
7. All components of the wet detention basin system shall be maintained in good working order.
8. Level spreaders or other structures that provide diffuse flow shall be maintained every six months. All
accumulated sediment and debris shall be removed from the structure, and a level elevation shall be
maintained across the entire flow spreading structure. Any down gradient erosion must be repaired and /or
replanted as necessary.
Page 1 of 2

I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify the Town of Cary of any problems with the system or
prior to any changes to the system or responsible party.
Print name:
Title:
Address:
Phone:
Signature:
Date:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the
lots have been sold and a resident of the subdivision has been named the president.
I, , a Notary Public for the State of
County of
, do hereby certify that
personally appeared before me this day of , and acknowledge the due
execution of the forgoing wet [wetland] detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires
Page 2 of 2

ENVIRONMENTAL IMPACT MAPS
INDIAN WELLS SUBDIVISION
CARY, NC
VICINITY MAP
SCALE: 1" =1000'
SHEET INDEX
1 COVER
2 OVERALL IMPACT MAP
3 IMPACT AREA "A"
4 CULVERT SECTION & PROFILE
DEVELOPER / OWNER
RALEIGH LAND FUND I, LLC
516 N. WEST STREET
RALEIGH, NC 27603
ADAM ASHBAUGH, PE, AICP
ADAM @LSTARLAND.COM
919.256.1981
H:\ 2014 \NCR142011 \DRAWINGS\PINI SEIS\IW= MAPS\140715 IMPACT MAPSDWG PRIMED BY: MROSELU 8.04.14 0 4:45 PM LAST SAVED BY: MRO
SITE DATA
Address: 7008, 7016, 7020, 7032, 7017, 7029, 7041 INDIAN
LTME- ENVIRONMENTAL IMPACT MAPS
INDIAN WELLS SUBDIVISION
CARY, NC
COVER SHEET D O � � � � TM
Shee t 1 of 4 IE N G H N IE IE a H iq G
DAIS CAD ID: PRQIECf NUMBER: NC, PLLC NCBELS P 1132
4011 WESTCHASE BLVD., SUITE 290
00 2014.07.21 1 KRW I NCR142011 PHONE: [phone] FAX [phone]
WELLS ROAD
REID#:
0081386, 0084257, 0150628, 0084258, 0084064,
0084259,0084260
PIN #:
0735 -53 -3365, 0735 -53 -1531, 0735 -53 -1126,
0735 -42 -3994, 0735 -52 -3632, 0735 -52 -1513,
0735 -42 -6432
Site Area: (ac.) 3.09, 2.50, 3.04, 11.10, 3.30, 6.72, 4.47:
Total = 34.22
Zoning:
R8 -CU
Watershed:
JORDAN LAKE (UPPER NEW HOPE)
LTME- ENVIRONMENTAL IMPACT MAPS
INDIAN WELLS SUBDIVISION
CARY, NC
COVER SHEET D O � � � � TM
Shee t 1 of 4 IE N G H N IE IE a H iq G
DAIS CAD ID: PRQIECf NUMBER: NC, PLLC NCBELS P 1132
4011 WESTCHASE BLVD., SUITE 290
00 2014.07.21 1 KRW I NCR142011 PHONE: [phone] FAX [phone]

/
H:\ 2014 \NCR142011 \DRAWNG9\PUN SDS\IMPACf WPS \140715 NVO WPS.BNG PPoNIED 8f: IROSEW 8.04.14 0 4:44 PM usr SAVED Ili: MRo
J
LOCATION
IMPACT TYPE
STREAM IMPACT
WETLANDS
IMPACT (SF)
BUFFER ZONE IMPACTS (SF)
LF
SF
ZONE I
ZONE 2
A
PERMANENT (ROAD CULVERT)
120
700
1,757
7897
6105
A
TEMPORARY (ROAD CULVERT)
20
204
9
137
0
A
TEMPORARY (UTILITY)
0
0
0
168
1199
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REVISIONS
REV DATE COMMENT BY
r,
THE FOLLOWING STATES REQUIRE NOTIFICATION BY
EXCAVATORS, DESIGNERS, OR ANY PERSON PREPARING TO
DISTURB THE EARTH'S SURFACE ANYWHERE IN THE STATE.
IN VIRGINIA, MARYLAND, THE DISTRICT OF COLUMBIA, AND
DELAWARE CALL - 811
(WV 1- 800 - 245 -4848) (PA 1-800- 242- 1776) (DC 1- 800 - 257 -7777)
(VA 1- 800 - 552- 7001) (MD 1-800- 257- 7777) (DE 1 -800- 282 -8555)
PROJECT No.: NCR142011
DRAWN BY:
MAR
CHECKED BY:
LML
DATE:
SCALE:
AS NOTED
CAD I.D.:
MAR
PROJECT: INDIAN
WELLS
SUBDIVISION
FOR
L STAR
MANAGEMENT
LOCATION OF SITE
INDIAN WELLS ROAD
WAKE COUNTY
CARY, NC
BOH LER
E N G I N E E R I N G
NC. PLLC NCBELS P -1132
4011 WESTCHASE BLVD., SUITE 290
RALEIGH, NC 27607
Phone: [phone]
Fax: [phone]
SHEET TITLE:
I .1" .e' I . I .
SHEET NUMBER:
2 ®f 4

STREAM CROSSING NOTES
1. A TEMPORARY STREAM CROSSING PER TOWN OF CARY DETAIL 04000.11 (3) WILL BE REQUIRED TO ACCESS THE AREA NORTH
OF THE MAIN STREAM CHANNEL. CULVERT SHALL BE INSTALLED PER SUMMARY (REFER TO SHEET 4). IF STREAM IS WET AT
TIME OF CONSTRUCTION, A TEMPORARY PUMP AROUND SHALL BE USED TO DIVERT FLOW AROUND THE WORK AREA. PUMP
SHALL BE DESIGNED TO CARRY NORMAL STREAM FLOW. PUMP AROUND IS ALLOWED A MAXIMUM OF 24 HOURS DURING DRY
WEATHER. IF STREAM WORK CANNOT BE COMPLETED IN 24 HOURS, A TEMPORARY CHANNEL LINED WITH FABRIC LINER SIZE
APPROPRIATELY TO HANDLE EXPECTED FLOWS WILL BE REQUIRED TO DIVERT STREAM.
2. CHANNEL SHALL BE ESTABLISHED BACK TO EXISTING CROSS SECTION AT DOWNSTREAM END OF CULVERT.
w\
i
,77
/
/
r
oF
/
/
1�4
�7 \
PERMANENT IMPACT AREAS TEMPORARY IMPACT AREAS
_ STREAM CHANNEL STREAM CHANNEL
/
® ZONE 1 (30) ZONE 1 (30)
/
® ZONE 2 (20) ® ZONE 2 (20) ,`{
Q WETLAND 0 WETLAND
LOCATION
IMPACTTYPE
STREAM IMPACT
WETLANDS
IMPACT(SF)
BUFFER ZONE IMPACTS (SF)
LF
SF
ZONE
ZONE
A
PERMANENT (ROAD CULVERT)
120
700
1,757
7897
6105
A
TEMPORARY (ROAD CULVERT)
20
204
9
137
0
A
TEMPORARY (UTILITY)
0
0
0
168
1199
ol
yF
0
H:\ 2014 \NCR142011 \DRAWINGS\PIAN SEIS\IMPACT NAPS\140715 IMPACT MAPS.DWG PRINTED BY: MROSEW &04.14 0 4:44 PM UST SAVED BY: MRO
PROJECT NAME ENVIRONMENTAL IMPACT MAPS
INDIAN WELLS SUBDIVISION
CARY, NC
SHEET RU-
IMPACT AREA "A "' DD O L � TM
Sheet 3 of 4 N G H N E IE R H N (G
SCALE DATE CAD IN PROJECT NUMBER: NC, NCBELS,SUT
4011 WESTC TCHASE BLVD., SUITE 290
1° = 40' 2014.07.21 1 KRW NCR142011 PHONE: [phone] FAX: [phone]
�Op
/
i

EXISTING
• a. NV 41 =
n ..
e
. a `
a,.
'--1' BURY
12'X6' BOX CULVERT CROSS SECTION
N.T.S.
LF 12'X6' RCP BOX CULVERT @ 3.53%
EXISTING
12'X6' BOX CULVERT PROFILE
N.T.S.
NOTE: THIS EXHIBIT IS FOR ILLUSTRATIVE PURPOSES ONLY.
H:\ 2014 \NCR142011 \DRAWINGS\PIAN SEIS\IMPACT MAPS\140715 IMPACT NOOK PRINTED BY: MROSELU &04.14 0 5:24 PM LAST SAVO BY: MRO
PROJECT NAME ENVIRONMENTAL IMPACT MAPS
INDIAN WELLS SUBDIVISION
CARY. NC
SHEET TITLE:-
CULVERT SECTION & PROFILE
Sheet 4 of 4
SCALE: DATE CAD ID: PROJECT NUMBER:
NTS 2014.07.21 1 KRW I NCR142
1p
INVERT = 295.5
D O I L �TM
IENGHNIEIEmHN(G
NC, PLLC NCBELS P -1132
4011 WESTCHASE BLVD., SUITE 290
PHONE: [phone] FAX: [phone]