SW5190701_Report_(SW)_20190715

CSIOESIIGN &
ENGINEERING, RLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
2537E. LYON STAT/ON RD, STE 102
PO BOX 361
SILER SQUARE
SIA
CREEDMOOR, NC 27522
919-625-7368
502 West Third Street, Siler City NC 27344
ENGINEER of RECORD: Chad E. Abbott, PE
[e-mail] / 919-625-7368
MAY 20, 2019 (Original Submittal)
JUNE 17, 2019 (2ND SUBMITTAL)

CaIOEESIGN &
ENGINEERING, PLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
2537E. LYON STAT/ON RD, STE 102
PO BOX 361
SIA NARRATIVE
CREEDMOOR, NC 27522
919-625-7368

2537 E. L YON STATION RD, STE 102
CaOEESIGN & PO BOX 361
ENGINEERING, PLLC CREEDMOOR, NC27522
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE 919-625-7368
SILER SQUARE APARTMENTS — STORMWATER NARRATIVE
MAY 20, 2019
PROJECT DATA:
• NAME: SILER SQUARE APARTMENTS
• PIN: 0062694
• PROPERTY SIZE: 101,017 SF (2.32 AC)
• ADDRESS: 502 W THIRD STREET, SILER CITY NC. 27344
• ZONING: R-3 (CUP 01-18)
• STORMWATER REG BASIN: PHASE II COMMUNITY
• RIVER BASIN: CAPE FEAR
• EXISTING BUA: 45,245 SF (44.79%)
• PROPOSED BUA: 10,878 SF
• TOTAL BUA: 56,123 SF (55.56% --- 24.10% INCREASE)
• DISTURBED AREA: 92,000 SF (2.11 AC)
• WATERSHED PROT. OVERLAY: N/A
SITE HISTORY & EXISTING HYDROLOGIC CONDITIONS: The existing property is an historic
school site that consisted of a single building fronting on West Third Street and parking areas to
the side and rear along North Evergreen Ave. and West Fourth Street. The site generally drains
southward towards the intersection of North Fir Ave. and West Third Street and is channelized
along the existing Curb & Gutter (West Third) and shallow road side swales/ditches for the
other streets around the property. Slopes are moderate (3-6%) with steeper slopes (2:1 and
3:1) along the West Third Street and North Fir Avenue frontages. There is no storm sewer
system available to the site and all flows discharge into the adjacent right of ways where they
continue southward along West Third until being captured by a curb inlet. The existing site is
either paved or grassed with a few trees around the perimeter, but no wooded sections.
PROJECT DESCRIPTION: The 2.32 acre subject property part of a Conditional Use Permit that
was approved for apartments by the Town of Siler City Council. The existing building will be
retrofit and rehabilitated to allow multifamily living as well as house the community center
amenities, etc. There will be 2 new buildings placed on the southwest side along North Fir Ave.,
Building 1 being +/-4,398 sf and Building 2 being +/-8,778 sf. The existing parking area and a
portion of the existing building will be removed and replaces with new parking, landscaping and
sidewalks. Two (2) amenity areas will be provided, one within the courtyard area created by the
existing building configuration and the otherjust off the proposed parking area, in the front
yard near Building #2.
LAND DISTURBANCE AND IMPERVIOUS SURFACES: As noted, approximately 2.11 acres of the
2.32 subject property and corresponding road frontage will be disturbed for the proposed

2537 E. L YON STATION RD, STE 102
CaOEESIGN cSL PO BOX 361
ENGINEERING, PLLC CREEDMOOR, NC27522
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE 919-625-7368
improvements. The site was already high density based on the exiting impervious coverage. As
noted above, there is a +/-10,878 sf increase in total impervious surfaces. These areas are
required to be treated per the Phase II Community requirements as well a the 10 yr— 24 hours
storm event detained to pre —developed rates to meet the Town of Siler City's Stormwater
Ordinance. The land disturbance will be permitted accordingly through the Raleigh Regional
office and proposed a skimmer basin in/near the area of the amenity area during construction.
It will subsequently be filled in and the area transformed into the proposed picnic shelter, etc.
WATERSHED PROTECTION OVERLAYS: The site is not part of any specific watershed protection
overlay. It is currently only +/-8.89% impervious and could be classified as low density in
regards to meeting the Phase II Rules for 85% TSS removal and controlling and treating the 1st
1/2 inch of rainfall. We are in the Cape Fear River Basin, which doesn't have adopted nutrient
goals for Nitrogen or Phosphorus, however each of these nutrients will be removed via the
proposed Filterra.
STREAMS & FLOODPLAINS: There are no streams or floodplains located on -site.
APPLICABLE REQUIREMENTS:
PEAK FLOW: The Town of Siler City requires that all post development flows match pre -
development flows. As noted, the site is already urban and would exhibit a min. 5 min.
Time of concentration. If the additional BUA/impervious area is captured, detained, and
released to the equivalent areas Pre -Development Rates, the Towns ordinance will be
met. We have an increase of +/-10,878 increase in BUA where the land cover is changing
from pervious/grass to impervious. Therefore, we are proposing to capture each
building, with its own Underground Storage (UGS) System that will have a structure at
the end of the line with a weir wall and orifice(s) to attenuate the flows accordingly. In
doing so, we are taking approximately 13,176 sf of impervious land cover and retaining
it to the pre -development rates as that 13,176 sf as grassed. All other portions of the
site are captured and released since the impervious areas remaining are at or below the
existing conditions.
• WATER QUALITY: As noted above, the project is considered to be high density due to
having more than 24% increase and therefore must meet the goals and objectives of the
Phase II Community Regulations. Those regulations require sites to capture and treat
the first 1" of runoff with a "PRIMARY" Stormwater Control Measure (SCM). We have
chosen to treat the parking area with a Filterra and again are treating more than the
actual increase in BUA since it is difficult to break the site up into just the area of
increase. The filterra will capture all runoff that flows to ST-3 where any flows in excess
of the first 1" will overflow down to ST-3.

2537 E. L YON STATION RD, STE 102
CaOEESIGN cSL PO BOX 361
ENGINEERING, PLLC CREEDMOOR, NC27522
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE 919-625-7368
METHODOLOGIES: AutoCAD Civil 3D and the existing topographic survey by "LAND SERVICES"
was used to delineate and obtain all land cover quantities/areas and flow patterns. Aerials from
Google Earth as provided by Autodesk and Chatham County GIS was used to assess land cover
types. All of the 'project area' or 'area of interest' was able to be captured at a common point
for both pre/post development where all flows would converge at a discharge point at/near the
existing collection point at the intersection of West Third Street and North Fir Ave. All pre/post
runoff and hydrographs were calculated using Hydraflow Hydrographs for AutoCAD Civil 3D.
The SCS hydrographs were used along with the generating the Time of Concentrations assumed
at 5 min. for both scenarios. All rainfall intensities and precipitation amounts were loaded into
Hydraflow from NOAA data as site specific values that NOAA interpolated from various
surrounding weather stations and is included with the stormwater calculations.
CONCLUSIONS:
As mentioned previously, the Hydraflow analysis for the 10yr-24hr event reveals that the areas
of increased BUA have been attenuated appropriately as well as additional storm events. The
filterra information is included to show that a 13'x7' Filterra unit is sufficient to treat the 16,242
sf of impervious area draining to it.

CaIOEESIGN &
ENGINEERING, PLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
2537E. LYON STAT/ON RD, STE 102
PO BOX 361
HYDRAFLOW
CREEDMOOR, NC 27522
919-625-7368
HYDROGRAPHS PEAK
FLOW ANALYSIS

1
Watershed Model Schematic Hydraflow Hydrographs Extension for Autodesk@ Civil 3D& 2019 by Autodesk, Inc. v202O
PRE-DEV BLDG A
-COST-DEV BLDG A
PRE-DEV BLDG BPOST-DEV BLDG B
r
r
5 - BLDG A - UGS ROUTE
6
- BLDG B - UGS ROUTE
Legend
Hid. Origin Description
1 SCS Runoff PRE-DEV BLDG A
2 SCS Runoff POST-DEV BLDG A
3 SCS Runoff PRE-DEV BLDG B
4 SCS Runoff POST-DEV BLDG B
5 Reservoir BLDG A- UGS ROUTE
6 Reservoir BLDG B - UGS ROUTE
Project: 2019-05-20 SILER PRE -POST
- INCREASE ONLY.gpw
Tuesday, 05 / 21 / 2019

Hydrograph Return Period Recap
Hydra w Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
Hydrograph
Inflow
Peak Outflow (cfs)
Hydrograph
No.
type
hyd(s)
Description
(origin)
1-yr
2-yr
3-yr
5-yr
10-yr
25-yr
50-yr
100-yr
1
SCS Runoff
------
0.125
0.197
-------
0.313
0.412
-------
-------
-------
PRE-DEV BLDG A
2
SCS Runoff
------
0.438
0.531
-------
0.666
0.773
-------
-------
-------
POST-DEV BLDG A
3
SCS Runoff
------
0.238
0.375
-------
0.594
0.782
-------
-------
-------
PRE-DEV BLDG B
4
SCS Runoff
------
0.833
1.009
-------
1.265
1.470
-------
-------
-------
POST-DEV BLDG B
5
Reservoir
2
0.122
0.142
-------
0.293
0.408
-------
-------
-------
BLDG A- UGS ROUTE
6
Reservoir
4
0.231
0.303
-------
0.592
0.762
-------
-------
-------
BLDG B - UGS ROUTE
Proj. file: 2019-05-20 SILER PRE -POST - INCREASE ONLY.gpw
Tuesday, 05 / 21 / 2019

Hydrograph Summary Repo rtH
ydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
0.125
1
718
265
------
------
------
PRE-DEV BLDG A
2
SCS Runoff
0.438
1
717
1,033
------
------
------
POST-DEV BLDG A
3
SCS Runoff
0.238
1
718
504
------
------
------
PRE-DEV BLDG B
4
SCS Runoff
0.833
1
717
1,962
------
------
------
POST-DEV BLDG B
5
Reservoir
0.122
1
725
1,031
2
104.53
288
BLDG A - UGS ROUTE
6
Reservoir
0.231
1
725
1,960
4
100.15
549
BLDG B - UGS ROUTE
2019-05-20 SILER PRE -POST - INCREASE
CHtftbfrgperiod: 1 Year
Tuesday, 05 / 21 / 2019

4
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 1
PRE-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.125 cfs
Storm frequency
= 1 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 265 cuft
Drainage area
= 0.100 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 2.99 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 70)] / 0.100
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
PRE-DEV BLDG A
Hyd. No. 1 -- 1 Year
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

5
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Hyd. No. 2
POST-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.438 cfs
Storm frequency
= 1 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 1,033 cuft
Drainage area
= 0.100 ac
Curve number
= 98*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 2.99 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 98)] / 0.100
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0 00
POST-DEV BLDG A
Hyd. No. 2 -- 1 Year
0 120 240 360 480 600 720 840 960
Hyd No. 2
Q (cfs)

Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 3
PRE-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
= 0.238 cfs
Storm frequency
= 1 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 504 cuft
Drainage area
= 0.190 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 2.99 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.190 x 70)] / 0.190
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
PRE-DEV BLDG B
Hyd. No. 3 -- 1 Year
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Time (min)

7
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Hyd. No. 4
POST-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
= 0.833 cfs
Storm frequency
= 1 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 1,962 cuft
Drainage area
= 0.190 ac
Curve number
= 98*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 2.99 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.195 x 98)] / 0.190
Q (cfs)
1.00
0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0 00
POST-DEV BLDG B
Hyd. No. 4 -- 1 Year
0 120 240 360 480 600 720 840 960
Hyd No. 4
Q (cfs)

Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 5
BLDG A - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.122 cfs
Storm frequency
= 1 yrs
Time to peak
= 725 min
Time interval
= 1 min
Hyd. volume
= 1,031 cuft
Inflow hyd. No.
= 2 - POST-DEV BLDG A
Max. Elevation
= 104.53 ft
Reservoir name
= BLDG A UGS
Max. Storage
= 288 cuft
Storage Indication method used.
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
BLDG A - UGS ROUTE
Hyd. No. 5 -- 1 Year
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 5 — Hyd No. 2 Total storage used = 288 cult Time (min)

Pond Report
Hydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Pond No. 1 - BLDG A UGS
Pond Data
UG Chambers -Invert elev. = 103.00 A Rise x Span = 3.00 x 3.00 ft, Barrel Len = 80.00 ft, No. Barrels = 1, Slope = 0.01 %, Headers = No
Stage / Storage Table
Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft)
0.00
103.00
n/a
0
0
0.30
103.30
n/a
29
29
0.60
103.60
n/a
51
80
0.90
103.90
n/a
62
142
1.20
104.20
n/a
69
211
1.50
104.50
n/a
72
283
1.80
104.80
n/a
72
355
2.11
105.11
n/a
69
423
2.41
105.41
n/a
62
486
2.71
105.71
n/a
51
537
3.01
106.01
n/a
29
566
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrFRsr]
[A]
[B]
[C]
[D]
Rise (in)
= 12.00
2.00
6.00
0.00
Crest Len (ft)
= 16.00
4.00
0.00
0.00
Span (in)
= 12.00
2.00
2.00
0.00
Crest El. (ft)
= 108.00
105.80
0.00
0.00
No. Barrels
= 1
1
1
0
WeirCoeff.
= 3.33
3.33
3.33
3.33
Invert El. (ft)
= 103.00
103.00
104.80
0.00
Weir Type
= 1
Rect
---
---
Length (ft)
= 20.00
0.00
0.00
0.00
Multi -Stage
= Yes
Yes
No
No
Slope (%)
= 5.00
0.00
0.00
n/a
N-Value
= .013
.013
.013
n/a
Orifice Coeff.
= 0.60
0.60
0.60
0.60
Exfil.(in/hr)
= 0.000 (by
Contour)
Multi -Stage
= n/a
Yes
Yes
No
TW Elev. (ft)
= 0.00
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s).
Stage / Storage / Discharge Table
Stage Storage Elevation CIvA CIvB CIvC PrfRsr WrA WrB WrC WrD Exfil User Total
ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs
0.00
0
103.00
0.00
0.00
0.00 ---
0.00
0.00 --- ---
0.03
3
103.03
0.00 is
0.00 is
0.00 ---
0.00
0.00 --- ---
0.06
6
103.06
0.01 is
0.01 is
0.00 ---
0.00
0.00 --- ---
0.09
9
103.09
0.01 is
0.01 is
0.00 ---
0.00
0.00 --- ---
0.12
12
103.12
0.02 is
0.02 is
0.00 ---
0.00
0.00 --- ---
0.15
14
103.15
0.03 is
0.03 is
0.00 ---
0.00
0.00 --- ---
0.18
17
103.18
0.03 is
0.03 is
0.00 ---
0.00
0.00 --- ---
0.21
20
103.21
0.04 is
0.04 is
0.00 ---
0.00
0.00 --- ---
0.24
23
103.24
0.04 is
0.04 is
0.00 ---
0.00
0.00 --- ---
0.27
26
103.27
0.04 is
0.04 is
0.00 ---
0.00
0.00 --- ---
0.30
29
103.30
0.05 is
0.05 is
0.00 ---
0.00
0.00 --- ---
0.33
34
103.33
0.05 is
0.05 is
0.00 ---
0.00
0.00 --- ---
0.36
39
103.36
0.05 is
0.05 is
0.00 ---
0.00
0.00 --- ---
0.39
44
103.39
0.06 is
0.06 is
0.00 ---
0.00
0.00 --- ---
0.42
49
103.42
0.06 is
0.06 is
0.00 ---
0.00
0.00 --- ---
0.45
55
103.45
0.06 is
0.06 is
0.00 ---
0.00
0.00 --- ---
0.48
60
103.48
0.07 is
0.06 is
0.00 ---
0.00
0.00 --- ---
0.51
65
103.51
0.07 is
0.07 is
0.00 ---
0.00
0.00 --- ---
0.54
70
103.54
0.07 is
0.07 is
0.00 ---
0.00
0.00 --- ---
0.57
75
103.57
0.07 is
0.07 is
0.00 ---
0.00
0.00 --- ---
0.60
80
103.60
0.07 is
0.07 is
0.00 ---
0.00
0.00 --- ---
0.63
86
103.63
0.08 is
0.07 is
0.00 ---
0.00
0.00 --- ---
0.66
93
103.66
0.08 is
0.08 is
0.00 ---
0.00
0.00 --- ---
0.69
99
103.69
0.08 is
0.08 is
0.00 ---
0.00
0.00 --- ---
0.72
105
103.72
0.08 is
0.08 is
0.00 ---
0.00
0.00 --- ---
0.75
111
103.75
0.08 is
0.08 is
0.00 ---
0.00
0.00 --- ---
0.78
118
103.78
0.08 is
0.08 is
0.00 ---
0.00
0.00 --- ---
0.81
124
103.81
0.09 is
0.09 is
0.00 ---
0.00
0.00 --- ---
0.84
130
103.84
0.09 is
0.09 is
0.00 ---
0.00
0.00 --- ---
0.87
136
103.87
0.09 is
0.09 is
0.00 ---
0.00
0.00 --- ---
0.90
142
103.90
0.09 is
0.09 is
0.00 ---
0.00
0.00 --- ---
0.93
149
103.93
0.10 is
0.09 is
0.00 ---
0.00
0.00 --- ---
--- --- 0.000
--- --- 0.001
--- --- 0.006
--- --- 0.012
--- --- 0.019
--- --- 0.027
--- --- 0.033
--- --- 0.036
--- --- 0.040
--- --- 0.044
--- --- 0.047
--- --- 0.050
--- --- 0.053
--- --- 0.056
--- --- 0.058
--- --- 0.061
--- --- 0.063
--- --- 0.066
--- --- 0.068
--- --- 0.070
--- --- 0.072
--- --- 0.074
--- --- 0.077
--- --- 0.079
--- --- 0.080
--- --- 0.082
--- --- 0.084
--- --- 0.086
--- --- 0.088
--- --- 0.090
--- --- 0.092
--- --- 0.093
Continues on next page

10
BLDG A UGS
Stage / Storage / Discharge Table
Stage Storage Elevation CIvA CIvB CIvC PrfRsr WrA WrB WrC WrD Exfil User Total
ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs
0.96
156
103.96
0.10 is
0.09 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.095
0.99
163
103.99
0.10 is
0.10 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.097
1.02
170
104.02
0.10 is
0.10 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.098
1.05
177
104.05
0.10 is
0.10 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.100
1.08
184
104.08
0.11 is
0.10 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.101
1.11
191
104.11
0.11 is
0.10 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.103
1.14
197
104.14
0.11 is
0.10 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.105
1.17
204
104.17
0.11 is
0.11 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.106
1.20
211
104.20
0.11 is
0.11 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.107
1.23
218
104.23
0.11 is
0.11 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.109
1.26
225
104.26
0.11 is
0.11 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.110
1.29
233
104.29
0.11 is
0.11 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.112
1.32
240
104.32
0.11 is
0.11 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.113
1.35
247
104.35
0.11 is
0.11 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.115
1.38
254
104.38
0.12 is
0.12 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.116
1.41
261
104.41
0.12 is
0.12 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.117
1.44
269
104.44
0.12 is
0.12 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.119
1.47
276
104.47
0.12 is
0.12 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.120
1.50
283
104.50
0.12 is
0.12 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.122
1.53
290
104.53
0.12 is
0.12 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.123
1.56
297
104.56
0.13 is
0.12 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.124
1.59
304
104.59
0.13 is
0.13 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.125
1.62
312
104.62
0.13 is
0.13 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.127
1.65
319
104.65
0.13 is
0.13 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.128
1.68
326
104.68
0.13 is
0.13 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.129
1.71
333
104.71
0.13 is
0.13 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.130
1.74
340
104.74
0.13 is
0.13 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.132
1.77
347
104.77
0.14 is
0.13 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.133
1.80
355
104.80
0.14 is
0.13 is
0.00 is ---
0.00
0.00 ---
--- --- --- 0.134
1.83
361
104.83
0.14 is
0.14 is
0.00 is ---
0.00
0.00 ---
--- --- --- 0.139
1.86
368
104.86
0.15 is
0.14 is
0.01 is ---
0.00
0.00 ---
--- --- --- 0.146
1.90
375
104.90
0.16 is
0.14 is
0.02 is ---
0.00
0.00 ---
--- --- --- 0.154
1.93
382
104.93
0.17 is
0.14 is
0.03 is ---
0.00
0.00 ---
--- --- --- 0.163
1.96
389
104.96
0.18 is
0.14 is
0.03 is ---
0.00
0.00 ---
--- --- --- 0.174
1.99
396
104.99
0.19 is
0.14 is
0.05 is ---
0.00
0.00 ---
--- --- --- 0.185
2.02
403
105.02
0.20 is
0.14 is
0.06 is ---
0.00
0.00 ---
--- --- --- 0.198
2.05
410
105.05
0.21 is
0.14 is
0.07 is ---
0.00
0.00 ---
--- --- --- 0.211
2.08
416
105.08
0.22 is
0.14 is
0.08 is ---
0.00
0.00 ---
--- --- --- 0.225
2.11
423
105.11
0.25 is
0.14 is
0.10 is ---
0.00
0.00 ---
--- --- --- 0.239
2.14
430
105.14
0.26 is
0.14 is
0.11 is ---
0.00
0.00 ---
--- --- --- 0.255
2.17
436
105.17
0.28 is
0.15 is
0.13 is ---
0.00
0.00 ---
--- --- --- 0.271
2.20
442
105.20
0.29 is
0.15 is
0.14 is ---
0.00
0.00 ---
--- --- --- 0.287
2.23
448
105.23
0.31 is
0.15 is
0.16 is ---
0.00
0.00 ---
--- --- --- 0.305
2.26
454
105.26
0.32 is
0.15 is
0.17 is ---
0.00
0.00 ---
--- --- --- 0.323
2.29
461
105.29
0.35 is
0.15 is
0.19 is ---
0.00
0.00 ---
--- --- --- 0.341
2.32
467
105.32
0.37 is
0.15 is
0.21 is ---
0.00
0.00 ---
--- --- --- 0.356
2.35
473
105.35
0.37 is
0.15 is
0.22 is ---
0.00
0.00 ---
--- --- --- 0.369
2.38
479
105.38
0.39 is
0.15 is
0.23 is ---
0.00
0.00 ---
--- --- --- 0.381
2.41
486
105.41
0.40 is
0.15 is
0.24 is ---
0.00
0.00 ---
--- --- --- 0.392
2.44
491
105.44
0.40 is
0.15 is
0.25 is ---
0.00
0.00 ---
--- --- --- 0.403
2.47
496
105.47
0.42 is
0.15 is
0.26 is ---
0.00
0.00 ---
--- --- --- 0.413
2.50
501
105.50
0.42 is
0.15 is
0.27 is ---
0.00
0.00 ---
--- --- --- 0.423
2.53
506
105.53
0.44 is
0.16 is
0.28 is ---
0.00
0.00 ---
--- --- --- 0.433
2.56
511
105.56
0.44 is
0.16 is
0.29 is ---
0.00
0.00 ---
--- --- --- 0.442
2.59
516
105.59
0.46 is
0.16 is
0.29 is ---
0.00
0.00 ---
--- --- --- 0.452
2.62
521
105.62
0.46 is
0.16 is
0.30 is ---
0.00
0.00 ---
--- --- --- 0.461
2.65
526
105.65
0.48 is
0.16 is
0.31 is ---
0.00
0.00 ---
--- --- --- 0.470
2.68
532
105.68
0.48 is
0.16 is
0.32 is ---
0.00
0.00 ---
--- --- --- 0.478
2.71
537
105.71
0.50 is
0.16 is
0.33 is ---
0.00
0.00 ---
--- --- --- 0.487
2.74
540
105.74
0.50 is
0.16 is
0.33 is ---
0.00
0.00 ---
--- --- --- 0.495
2.77
542
105.77
0.52 is
0.16 is
0.34 is ---
0.00
0.00 ---
--- --- --- 0.503
2.80
545
105.80
0.52 is
0.16 is
0.35 is ---
0.00
0.00 ---
--- --- --- 0.511
2.83
548
105.83
0.58 is
0.16 is
0.35 is ---
0.00
0.06 ---
--- --- --- 0.579
2.86
551
105.86
0.71 is
0.16 is
0.36 is ---
0.00
0.18 ---
--- --- --- 0.709
2.89
554
105.89
0.89 is
0.16 is
0.37 is ---
0.00
0.35 ---
--- --- --- 0.876
2.92
557
105.92
1.07 is
0.16 is
0.37 is ---
0.00
0.54 ---
--- --- --- 1.074
2.95
560
105.95
1.30 is
0.16 is
0.38 is ---
0.00
0.76 ---
--- --- --- 1.299
2.98
563
105.98
1.55 is
0.16 is
0.39 is ---
0.00
1.00 ---
--- --- --- 1.546
3.01
566
106.01
1.82 is
0.16 is
0.39 is ---
0.00
1.26 ---
--- --- --- 1.815
... End

Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 6
BLDG B - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.231 cfs
Storm frequency
= 1 yrs
Time to peak
= 725 min
Time interval
= 1 min
Hyd. volume
= 1,960 cuft
Inflow hyd. No.
= 4 - POST-DEV BLDG B
Max. Elevation
= 100.15 ft
Reservoir name
= BLDG BUGS
Max. Storage
= 549 cuft
Storage Indication method used.
Q (cfs)
1.00
0.90
WE
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
0
BLDG B - UGS ROUTE
Hyd. No. 6 -- 1 Year
Q (cfs)
1.00
0.90
N :M
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 6 — Hyd No. 4 Total storage used = 549 cult Time (min)

Pond Report
12
Hydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Pond No. 2 - BLDG B UGS
Pond Data
UG Chambers -Invert elev. = 98.00 ft, Rise x Span = 4.00 x 4.00 ft, Barrel Len = 80.00 ft, No. Barrels = 1, Slope = 0.01 %, Headers = No
Stage / Storage Table
Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft)
0.00
98.00
n/a
0
0
0.40
98.40
n/a
52
52
0.80
98.80
n/a
91
143
1.20
99.20
n/a
111
253
1.60
99.60
n/a
122
376
2.00
100.00
n/a
127
503
2.40
100.40
n/a
128
630
2.81
100.81
n/a
122
752
3.21
101.21
n/a
111
863
3.61
101.61
n/a
91
954
4.01
102.01
n/a
52
1,006
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrFRsr]
[A]
[B]
[C]
[D]
Rise (in)
= 12.00
2.50
8.00
0.00
Crest Len (ft)
= 20.00
5.00
0.00
0.00
Span (in)
= 12.00
2.00
2.00
0.00
Crest El. (ft)
= 102.50
101.80
0.00
0.00
No. Barrels
= 1
1
1
0
WeirCoeff.
= 3.33
3.33
3.33
3.33
Invert El. (ft)
= 98.00
98.00
100.40
0.00
Weir Type
= 1
Rect
---
---
Length (ft)
= 20.00
0.00
0.00
0.00
Multi -Stage
= Yes
Yes
No
No
Slope (%)
= 1.00
0.00
0.00
n/a
N-Value
= .013
.013
.013
n/a
Orifice Coeff.
= 0.60
0.60
0.60
0.60
Exfil.(in/hr)
= 0.000 (by
Wet area)
Multi -Stage
= n/a
Yes
Yes
No
TW Elev. (ft)
= 0.00
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s).
Stage / Storage / Discharge Table
Stage Storage Elevation CIvA CIvB CIvC PrfRsr WrA WrB WrC WrD Exfil User Total
ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs
0.00
0
98.00
0.00
0.00
0.00 ---
0.00
0.00 --- ---
0.04
5
98.04
0.00 is
0.00 is
0.00 ---
0.00
0.00 --- ---
0.08
10
98.08
0.01 is
0.01 is
0.00 ---
0.00
0.00 --- ---
0.12
16
98.12
0.02 is
0.02 is
0.00 ---
0.00
0.00 --- ---
0.16
21
98.16
0.04 is
0.03 is
0.00 ---
0.00
0.00 --- ---
0.20
26
98.20
0.05 is
0.05 is
0.00 ---
0.00
0.00 --- ---
0.24
31
98.24
0.06 is
0.06 is
0.00 ---
0.00
0.00 --- ---
0.28
36
98.28
0.07 is
0.07 is
0.00 ---
0.00
0.00 --- ---
0.32
41
98.32
0.07 is
0.07 is
0.00 ---
0.00
0.00 --- ---
0.36
47
98.36
0.08 is
0.08 is
0.00 ---
0.00
0.00 --- ---
0.40
52
98.40
0.09 is
0.09 is
0.00 ---
0.00
0.00 --- ---
0.44
61
98.44
0.09 is
0.09 is
0.00 ---
0.00
0.00 --- ---
0.48
70
98.48
0.10 is
0.10 is
0.00 ---
0.00
0.00 --- ---
0.52
79
98.52
0.11 is
0.10 is
0.00 ---
0.00
0.00 --- ---
0.56
88
98.56
0.11 is
0.11 is
0.00 ---
0.00
0.00 --- ---
0.60
97
98.60
0.11 is
0.11 is
0.00 ---
0.00
0.00 --- ---
0.64
106
98.64
0.12 is
0.12 is
0.00 ---
0.00
0.00 --- ---
0.68
115
98.68
0.12 is
0.12 is
0.00 ---
0.00
0.00 --- ---
0.72
124
98.72
0.13 is
0.12 is
0.00 ---
0.00
0.00 --- ---
0.76
134
98.76
0.13 is
0.13 is
0.00 ---
0.00
0.00 --- ---
0.80
143
98.80
0.14 is
0.13 is
0.00 ---
0.00
0.00 --- ---
0.84
154
98.84
0.14 is
0.14 is
0.00 ---
0.00
0.00 --- ---
0.88
165
98.88
0.14 is
0.14 is
0.00 ---
0.00
0.00 --- ---
0.92
176
98.92
0.15 is
0.14 is
0.00 ---
0.00
0.00 --- ---
0.96
187
98.96
0.15 is
0.15 is
0.00 ---
0.00
0.00 --- ---
1.00
198
99.00
0.16 is
0.15 is
0.00 ---
0.00
0.00 --- ---
1.04
209
99.04
0.16 is
0.15 is
0.00 ---
0.00
0.00 --- ---
1.08
220
99.08
0.16 is
0.16 is
0.00 ---
0.00
0.00 --- ---
1.12
231
99.12
0.17 is
0.16 is
0.00 ---
0.00
0.00 --- ---
1.16
242
99.16
0.17 is
0.16 is
0.00 ---
0.00
0.00 --- ---
1.20
253
99.20
0.17 is
0.17 is
0.00 ---
0.00
0.00 --- ---
1.24
266
99.24
0.18 is
0.17 is
0.00 ---
0.00
0.00 --- ---
--- --- 0.000
--- --- 0.004
--- --- 0.011
--- --- 0.022
--- --- 0.035
--- --- 0.050
--- --- 0.059
--- --- 0.067
--- --- 0.073
--- --- 0.080
--- --- 0.086
--- --- 0.091
--- --- 0.097
--- --- 0.102
--- --- 0.107
--- --- 0.111
--- --- 0.116
--- --- 0.120
--- --- 0.124
--- --- 0.129
--- --- 0.132
--- --- 0.136
--- --- 0.140
--- --- 0.144
--- --- 0.148
--- --- 0.151
--- --- 0.155
--- --- 0.158
--- --- 0.161
--- --- 0.165
--- --- 0.168
--- --- 0.171
Continues on next page

13
BLDG B UGS
Stage / Storage / Discharge Table
Stage Storage Elevation CIvA CIvB CIvC PrfRsr WrA WrB WrC WrD Exfil User Total
ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs
1.28
278
99.28
0.18 is
0.17 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.174
1.32
290
99.32
0.18 is
0.18 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.177
1.36
302
99.36
0.18 is
0.18 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.180
1.40
314
99.40
0.19 is
0.18 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.183
1.44
327
99.44
0.19 is
0.19 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.186
1.48
339
99.48
0.19 is
0.19 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.189
1.52
351
99.52
0.20 is
0.19 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.191
1.56
363
99.56
0.20 is
0.19 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.194
1.60
376
99.60
0.20 is
0.20 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.197
1.64
388
99.64
0.20 is
0.20 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.200
1.68
401
99.68
0.20 is
0.20 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.202
1.72
414
99.72
0.21 is
0.21 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.205
1.76
426
99.76
0.21 is
0.21 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.208
1.80
439
99.80
0.21 is
0.21 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.210
1.84
452
99.84
0.21 is
0.21 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.213
1.88
465
99.88
0.22 is
0.22 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.215
1.92
477
99.92
0.22 is
0.22 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.218
1.96
490
99.96
0.22 is
0.22 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.220
2.00
503
100.00
0.22 is
0.22 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.223
2.04
516
100.04
0.23 is
0.23 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.225
2.08
528
100.08
0.24 is
0.23 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.228
2.12
541
100.12
0.24 is
0.23 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.230
2.16
554
100.16
0.24 is
0.23 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.232
2.20
567
100.20
0.24 is
0.23 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.235
2.24
579
100.24
0.24 is
0.24 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.237
2.28
592
100.28
0.24 is
0.24 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.239
2.32
605
100.32
0.25 is
0.24 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.241
2.36
618
100.36
0.25 is
0.24 is
0.00 ---
0.00
0.00 ---
--- --- --- 0.244
2.40
630
100.40
0.25 is
0.25 is
0.00 is ---
0.00
0.00 ---
--- --- --- 0.246
2.44
643
100.44
0.26 is
0.25 is
0.01 is ---
0.00
0.00 ---
--- --- --- 0.253
2.48
655
100.48
0.26 is
0.25 is
0.01 is ---
0.00
0.00 ---
--- --- --- 0.264
2.53
667
100.53
0.28 is
0.25 is
0.03 is ---
0.00
0.00 ---
--- --- --- 0.277
2.57
679
100.57
0.29 is
0.25 is
0.04 is ---
0.00
0.00 ---
--- --- --- 0.292
2.61
691
100.61
0.31 is
0.26 is
0.05 is ---
0.00
0.00 ---
--- --- --- 0.308
2.65
704
100.65
0.34 is
0.26 is
0.07 is ---
0.00
0.00 ---
--- --- --- 0.326
2.69
716
100.69
0.35 is
0.26 is
0.09 is ---
0.00
0.00 ---
--- --- --- 0.345
2.73
728
100.73
0.37 is
0.26 is
0.11 is ---
0.00
0.00 ---
--- --- --- 0.366
2.77
740
100.77
0.39 is
0.26 is
0.13 is ---
0.00
0.00 ---
--- --- --- 0.388
2.81
752
100.81
0.42 is
0.26 is
0.15 is ---
0.00
0.00 ---
--- --- --- 0.410
2.85
763
100.85
0.44 is
0.27 is
0.17 is ---
0.00
0.00 ---
--- --- --- 0.434
2.89
775
100.89
0.46 is
0.27 is
0.19 is ---
0.00
0.00 ---
--- --- --- 0.459
2.93
786
100.93
0.50 is
0.27 is
0.22 is ---
0.00
0.00 ---
--- --- --- 0.485
2.97
797
100.97
0.52 is
0.27 is
0.24 is ---
0.00
0.00 ---
--- --- --- 0.512
3.01
808
101.01
0.54 is
0.27 is
0.27 is ---
0.00
0.00 ---
--- --- --- 0.539
3.05
819
101.05
0.58 is
0.27 is
0.29 is ---
0.00
0.00 ---
--- --- --- 0.568
3.09
830
101.09
0.60 is
0.27 is
0.32 is ---
0.00
0.00 ---
--- --- --- 0.593
3.13
841
101.13
0.62 is
0.28 is
0.34 is ---
0.00
0.00 ---
--- --- --- 0.612
3.17
852
101.17
0.64 is
0.28 is
0.35 is ---
0.00
0.00 ---
--- --- --- 0.630
3.21
863
101.21
0.65 is
0.28 is
0.37 is ---
0.00
0.00 ---
--- --- --- 0.648
3.25
872
101.25
0.67 is
0.28 is
0.38 is ---
0.00
0.00 ---
--- --- --- 0.665
3.29
881
101.29
0.69 is
0.28 is
0.40 is ---
0.00
0.00 ---
--- --- --- 0.681
3.33
890
101.33
0.71 is
0.28 is
0.41 is ---
0.00
0.00 ---
--- --- --- 0.697
3.37
899
101.37
0.71 is
0.29 is
0.43 is ---
0.00
0.00 ---
--- --- --- 0.713
3.41
908
101.41
0.74 is
0.29 is
0.44 is ---
0.00
0.00 ---
--- --- --- 0.728
3.45
918
101.45
0.74 is
0.29 is
0.45 is ---
0.00
0.00 ---
--- --- --- 0.742
3.49
927
101.49
0.76 is
0.29 is
0.46 is ---
0.00
0.00 ---
--- --- --- 0.756
3.53
936
101.53
0.79 is
0.29 is
0.48 is ---
0.00
0.00 ---
--- --- --- 0.770
3.57
945
101.57
0.79 is
0.30 is
0.49 is ---
0.00
0.00 ---
--- --- --- 0.784
3.61
954
101.61
0.81 is
0.30 is
0.50 is ---
0.00
0.00 ---
--- --- --- 0.797
3.65
959
101.65
0.81 is
0.30 is
0.51 is ---
0.00
0.00 ---
--- --- --- 0.810
3.69
964
101.69
0.84 is
0.30 is
0.52 is ---
0.00
0.00 ---
--- --- --- 0.823
3.73
969
101.73
0.84 is
0.30 is
0.53 is ---
0.00
0.00 ---
--- --- --- 0.836
3.77
975
101.77
0.86 is
0.30 is
0.54 is ---
0.00
0.00 ---
--- --- --- 0.848
3.81
980
101.81
0.89 is
0.31 is
0.55 is ---
0.00
0.01 ---
--- --- --- 0.871
3.85
985
101.85
1.04 is
0.30 is
0.56 is ---
0.00
0.17 ---
--- --- --- 1.043
3.89
990
101.89
1.32 oc
0.30 is
0.57 is ---
0.00
0.43 ---
--- --- --- 1.310
3.93
995
101.93
1.65 oc
0.30 is
0.58 is ---
0.00
0.76 ---
--- --- --- 1.643
3.97
1,000
101.97
2.03 oc
0.29 is
0.59 is ---
0.00
1.15 ---
--- --- --- 2.027
4.01
1,006
102.01
2.47 oc
0.28 is
0.60 is ---
0.00
1.58 ---
--- --- --- 2.467
... End

14
Hydrograph Summary Repo rtH
ydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
0.197
1
718
403
------
------
------
PRE-DEV BLDG A
2
SCS Runoff
0.531
1
717
1,264
------
------
------
POST-DEV BLDG A
3
SCS Runoff
0.375
1
718
766
------
------
------
PRE-DEV BLDG B
4
SCS Runoff
1.009
1
717
2,401
------
------
------
POST-DEV BLDG B
5
Reservoir
0.142
1
725
1,262
2
104.85
365
BLDG A - UGS ROUTE
6
Reservoir
0.303
1
725
2,400
4
100.60
687
BLDG B - UGS ROUTE
2019-05-20 SILER PRE -POST - INCREASE
CHtftbfrgperiod: 2 Year
Tuesday, 05 / 21 / 2019

15
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 1
PRE-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.197 cfs
Storm frequency
= 2 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 403 cuft
Drainage area
= 0.100 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 3.61 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 70)] / 0.100
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
PRE-DEV BLDG A
Hyd. No. 1 -- 2 Year
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

16
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Hyd. No. 2
POST-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.531 cfs
Storm frequency
= 2 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 1,264 cuft
Drainage area
= 0.100 ac
Curve number
= 98*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 3.61 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 98)] / 0.100
Q (cfs)
POST-DEV BLDG A
Hyd. No. 2 -- 2 Year
Q (cfs)
MI
0
120 240 360 480 600 720 840 960
Hyd No. 2
1080 1200
Time (min)

17
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 3
PRE-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
= 0.375 cfs
Storm frequency
= 2 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 766 cuft
Drainage area
= 0.190 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 3.61 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.190 x 70)] / 0.190
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
PRE-DEV BLDG B
Hyd. No. 3 -- 2 Year
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Time (min)

Hydrograph Report
18
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Hyd. No. 4
POST-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
Storm frequency
= 2 yrs
Time to peak
Time interval
= 1 min
Hyd. volume
Drainage area
= 0.190 ac
Curve number
Basin Slope
= 0.0 %
Hydraulic length
Tc method
= User
Time of conc. (Tc)
Total precip.
= 3.61 in
Distribution
Storm duration
= 24 hrs
Shape factor
Composite (Area/CN) = [(0.195 x 98)] / 0.190
Q (cfs)
2.00
1.00
0.00
0 120 240 360 480 600 720 840
Hyd No. 4
POST-DEV BLDG B
Hyd. No. 4 -- 2 Year
Tuesday, 05 / 21 / 2019
= 1.009 cfs
= 717 min
= 2,401 cuft
= 98*
= 0 ft
= 5.00 min
= Type II
= 484
960 1080
Q (cfs)
2.00
1.00
0.00
1200
Time (min)

19
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 5
BLDG A - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.142 cfs
Storm frequency
= 2 yrs
Time to peak
= 725 min
Time interval
= 1 min
Hyd. volume
= 1,262 cuft
Inflow hyd. No.
= 2 - POST-DEV BLDG A
Max. Elevation
= 104.85 ft
Reservoir name
= BLDG A UGS
Max. Storage
= 365 cuft
Storage Indication method used.
Q (cfs)
1.00
0.90
WE
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
0
BLDG A - UGS ROUTE
Hyd. No. 5 -- 2 Year
Q (cfs)
1.00
0.90
N :M
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 5 — Hyd No. 2 Total storage used = 365 cult Time (min)

Hydrograph
Report
20
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc.
v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 6
BLDG B - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.303 cfs
Storm frequency
= 2 yrs
Time to peak
= 725 min
Time interval
= 1 min
Hyd. volume
= 2,400 cuft
Inflow hyd. No.
= 4 - POST-DEV BLDG B
Max. Elevation
= 100.60 ft
Reservoir name
= BLDG BUGS
Max. Storage
= 687 cuft
Storage Indication method used
Q (cfs)
2.00
1.00
BLDG B - UGS ROUTE
Hyd. No. 6 -- 2 Year
120 240 360 480 600 720
Hyd No. 6 Hyd No. 4
Q (cfs)
2.00
1.00
0.00
840 960 1080 1200 1320 1440 1560
Total storage used = 687 cult Time (min)

21
Hydrograph Summary Repo rtH
ydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
0.313
1
718
629
------
------
------
PRE-DEV BLDG A
2
SCS Runoff
0.666
1
717
1,600
------
------
------
POST-DEV BLDG A
3
SCS Runoff
0.594
1
718
1,195
------
------
------
PRE-DEV BLDG B
4
SCS Runoff
1.265
1
717
3,040
------
------
------
POST-DEV BLDG B
5
Reservoir
0.293
1
723
1,598
2
105.21
444
BLDG A - UGS ROUTE
6
Reservoir
0.592
1
723
3,039
4
101.09
829
BLDG B - UGS ROUTE
2019-05-20 SILER PRE -POST - INCREASE
CHtftbfrgperiod: 5 Year
Tuesday, 05 / 21 / 2019

22
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 1
PRE-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.313 cfs
Storm frequency
= 5 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 629 cuft
Drainage area
= 0.100 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 4.51 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 70)] / 0.100
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
PRE-DEV BLDG A
Hyd. No. 1 -- 5 Year
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

23
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Hyd. No. 2
POST-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.666 cfs
Storm frequency
= 5 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 1,600 cuft
Drainage area
= 0.100 ac
Curve number
= 98*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 4.51 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 98)] / 0.100
Q (cfs)
POST-DEV BLDG A
Hyd. No. 2 -- 5 Year
Q (cfs)
0
120 240 360 480 600 720 840 960
Hyd No. 2
1080 1200
Time (min)

24
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 3
PRE-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
= 0.594 cfs
Storm frequency
= 5 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 1,195 cuft
Drainage area
= 0.190 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 4.51 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.190 x 70)] / 0.190
Q (cfs)
1.00
0.90
WE
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
0
PRE-DEV BLDG B
Hyd. No. 3 -- 5 Year
Q (cfs)
1.00
0.90
M :M
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Time (min)

Hydrograph Report
25
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Hyd. No. 4
POST-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
Storm frequency
= 5 yrs
Time to peak
Time interval
= 1 min
Hyd. volume
Drainage area
= 0.190 ac
Curve number
Basin Slope
= 0.0 %
Hydraulic length
Tc method
= User
Time of conc. (Tc)
Total precip.
= 4.51 in
Distribution
Storm duration
= 24 hrs
Shape factor
Composite (Area/CN) = [(0.195 x 98)] / 0.190
Q (cfs)
2.00
1.00
0.00
0 120 240 360 480 600 720 840
Hyd No. 4
POST-DEV BLDG B
Hyd. No. 4 -- 5 Year
Tuesday, 05 / 21 / 2019
= 1.265 cfs
= 717 min
= 3,040 cuft
= 98*
= 0 ft
= 5.00 min
= Type II
= 484
960 1080
Q (cfs)
2.00
1.00
0.00
1200
Time (min)

26
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 5
BLDG A - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.293 cfs
Storm frequency
= 5 yrs
Time to peak
= 723 min
Time interval
= 1 min
Hyd. volume
= 1,598 cuft
Inflow hyd. No.
= 2 - POST-DEV BLDG A
Max. Elevation
= 105.21 ft
Reservoir name
= BLDG A UGS
Max. Storage
= 444 cuft
Storage Indication method used.
Q (cfs)
1.00
0.90
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0 00
BLDG A - UGS ROUTE
Hyd. No. 5 -- 5 Year
Q (cfs)
1.00
0.90
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0 00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 5 — Hyd No. 2 Total storage used = 444 cult

Hydrograph
Report
27
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc.
v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 6
BLDG B - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.592 cfs
Storm frequency
= 5 yrs
Time to peak
= 723 min
Time interval
= 1 min
Hyd. volume
= 3,039 cuft
Inflow hyd. No.
= 4 - POST-DEV BLDG B
Max. Elevation
= 101.09 ft
Reservoir name
= BLDG BUGS
Max. Storage
= 829 cuft
Storage Indication method used
Q (cfs)
2.00
1.00
BLDG B - UGS ROUTE
Hyd. No. 6 -- 5 Year
120 240 360 480 600 720
Hyd No. 6 Hyd No. 4
Q (cfs)
2.00
1.00
0.00
840 960 1080 1200 1320 1440 1560
Total storage used = 829 cult Time (min)

28
Hydrograph Summary Repo rtH
ydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
0.412
1
718
827
------
------
------
PRE-DEV BLDG A
2
SCS Runoff
0.773
1
717
1,869
------
------
------
POST-DEV BLDG A
3
SCS Runoff
0.782
1
718
1,571
------
------
------
PRE-DEV BLDG B
4
SCS Runoff
1.470
1
717
3,551
------
------
------
POST-DEV BLDG B
5
Reservoir
0.408
1
722
1,867
2
105.46
493
BLDG A - UGS ROUTE
6
Reservoir
0.762
1
722
3,550
4
101.51
930
BLDG B - UGS ROUTE
2019-05-20 SILER PRE -POST - INCREASE
CHtftbfrgperiod: 10 Year
Tuesday, 05 / 21 / 2019

29
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 1
PRE-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.412 cfs
Storm frequency
= 10 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 827 cuft
Drainage area
= 0.100 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 5.23 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 70)] / 0.100
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
PRE-DEV BLDG A
Hyd. No. 1 -- 10 Year
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

30
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Hyd. No. 2
POST-DEV BLDG A
Hydrograph type
= SCS Runoff
Peak discharge
= 0.773 cfs
Storm frequency
= 10 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 1,869 cuft
Drainage area
= 0.100 ac
Curve number
= 98*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 5.23 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.100 x 98)] / 0.100
Q (cfs)
1.00
0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0 00
POST-DEV BLDG A
Hyd. No. 2 -- 10 Year
0 120 240 360 480 600 720 840 960
Hyd No. 2
Q (cfs)

31
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 3
PRE-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
= 0.782 cfs
Storm frequency
= 10 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 1,571 cuft
Drainage area
= 0.190 ac
Curve number
= 70*
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 5.23 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Composite (Area/CN) = [(0.190 x 70)] / 0.190
Q (cfs)
1.00
0.90
WE
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
0
PRE-DEV BLDG B
Hyd. No. 3 -- 10 Year
Q (cfs)
1.00
0.90
M :M
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Time (min)

Hydrograph Report
32
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Hyd. No. 4
POST-DEV BLDG B
Hydrograph type
= SCS Runoff
Peak discharge
Storm frequency
= 10 yrs
Time to peak
Time interval
= 1 min
Hyd. volume
Drainage area
= 0.190 ac
Curve number
Basin Slope
= 0.0 %
Hydraulic length
Tc method
= User
Time of conc. (Tc)
Total precip.
= 5.23 in
Distribution
Storm duration
= 24 hrs
Shape factor
Composite (Area/CN) = [(0.195 x 98)] / 0.190
Q (cfs)
2.00
1.00
0.00
0 120 240 360 480 600 720 840
Hyd No. 4
POST-DEV BLDG B
Hyd. No. 4 -- 10 Year
Tuesday, 05 / 21 / 2019
= 1.470 cfs
= 717 min
= 3,551 cuft
= 98*
= 0 ft
= 5.00 min
= Type II
= 484
960 1080
Q (cfs)
2.00
1.00
0.00
1200
Time (min)

33
Hydrograph Report
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 5
BLDG A - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.408 cfs
Storm frequency
= 10 yrs
Time to peak
= 722 min
Time interval
= 1 min
Hyd. volume
= 1,867 cuft
Inflow hyd. No.
= 2 - POST-DEV BLDG A
Max. Elevation
= 105.46 ft
Reservoir name
= BLDG A UGS
Max. Storage
= 493 cuft
Storage Indication method used.
Q (cfs)
1.00
0.90
WE
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
0
BLDG A - UGS ROUTE
Hyd. No. 5 -- 10 Year
Q (cfs)
1.00
0.90
N :M
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 5 — Hyd No. 2 Total storage used = 493 cult Time (min)

Hydrograph
Report
34
Hydraflow Hydrographs Extension for AUtodeskS Civil 3DO 2019 by Autodesk, Inc.
v2020
Tuesday, 05 / 21 / 2019
Hyd. No. 6
BLDG B - UGS ROUTE
Hydrograph type
= Reservoir
Peak discharge
= 0.762 cfs
Storm frequency
= 10 yrs
Time to peak
= 722 min
Time interval
= 1 min
Hyd. volume
= 3,550 cuft
Inflow hyd. No.
= 4 - POST-DEV BLDG B
Max. Elevation
= 101.51 ft
Reservoir name
= BLDG BUGS
Max. Storage
= 930 cuft
Storage Indication method used
Q (cfs)
2.00
1.00
BLDG B - UGS ROUTE
Hyd. No. 6 -- 10 Year
120 240 360 480 600 720
Hyd No. 6 Hyd No. 4
Q (cfs)
2.00
1.00
0.00
840 960 1080 1200 1320 1440 1560
Total storage used = 930 cult Time (min)

35
Hydraflow Rainfall Report
Hydraflow Hydrographs Extension for Autodeskg Civil 3DO 2019 by Autodesk, Inc. v2020 Tuesday, 05 / 21 / 2019
Return
Period
Intensity -Duration -Frequency Equation Coefficients (FHA)
(Yrs)
B
D
E
(NIA)
1
63.8568
12.6000
0.8882
--------
2
73.1817
12.7000
0.8750
--------
3
0.0000
0.0000
0.0000
--------
5
79.8313
13.1000
0.8465
--------
10
77.3185
12.7000
0.8111
--------
25
64.6079
11.1000
0.7420
--------
50
58.1851
10.2000
0.6990
--------
100
50.8258
9.0000
0.6516
--------
File name: 2019-05-20 NOAA IDF - SILER CITY.IDF
Intensity = B / (Tc + D)^E
Return
Period
Intensity Values (in/hr)
(Yrs)
5 min
10
15
20
25
30
35
40
45
50
55
60
1
5.00
4.00
3.35
2.89
2.55
2.28
2.07
1.89
1.74
1.62
1.51
1.42
2
5.92
4.76
4.00
3.46
3.06
2.74
2.49
2.28
2.11
1.96
1.83
1.72
3
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
5
6.88
5.60
4.74
4.13
3.66
3.30
3.01
2.77
2.56
2.39
2.24
2.11
10
7.52
6.14
5.23
4.57
4.07
3.68
3.36
3.10
2.88
2.69
2.53
2.39
25
8.22
6.72
5.74
5.04
4.51
4.10
3.77
3.49
3.25
3.05
2.88
2.73
50
8.68
7.12
6.10
5.37
4.83
4.40
4.05
3.77
3.53
3.32
3.14
2.98
100
9.10
7.46
6.41
5.66
5.11
4.67
4.32
4.02
3.78
3.57
3.38
3.22
Tc = time in minutes. Values may exceed 60.
D HOME\SILER SCHOOL 5-20\CIVIL-18-023\Desian\Stormwater\Hvdraflow\2019-05-20 NOAA PCP - SILER CITY.DCD
Storm
Rainfall Precipitation Table (in)
Distribution
1-yr
2-yr
3-yr
5-yr
10-yr
25-yr
50-yr
100-yr
SCS 24-hour
2.99
3.61
0.00
4.51
5.23
6.19
6.95
7.74
SCS 6-Hr
2.19
2.65
0.00
3.30
3.79
4.45
4.97
5.49
Huff-1 st
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-2nd
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-3rd
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-4th
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-Indy
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Custom
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00

Hydraflow Table of Contents
2019-05-20 SILER PRE -POST - INCREASE ONLY.gpw
Hydraflow Hydrographs Extension for Autodeskg Civil 3DO 2019 by Autodesk, Inc. v2020
Tuesday, 05 / 21 / 2019
Watershed Model Schematic...................................................................................... 1
Hydrograph Return Period Recap............................................................................. 2
1 -Year
SummaryReport.........................................................................................................................
3
HydrographReports...................................................................................................................
4
Hydrograph No.
1, SCS Runoff, PRE-DEV BLDG A...............................................................
4
Hydrograph No.
2, SCS Runoff, POST-DEV BLDG A.............................................................
5
Hydrograph No.
3, SCS Runoff, PRE-DEV BLDG B................................................................
6
Hydrograph No.
4, SCS Runoff, POST-DEV BLDG B..............................................................
7
Hydrograph No.
5, Reservoir, BLDG A - UGS ROUTE...........................................................
8
Pond Report
- BLDG A UGS................................................................................................
9
Hydrograph No.
6, Reservoir, BLDG B - UGS ROUTE..........................................................
11
Pond Report
- BLDG B UGS.............................................................................................
12
2 - Year
SummaryReport
.......................................................................................................................
14
HydrographReports.................................................................................................................
15
Hydrograph No.
1, SCS Runoff, PRE-DEV BLDG A.............................................................
15
Hydrograph No.
2, SCS Runoff, POST-DEV BLDG A ...........................................................
16
Hydrograph No.
3, SCS Runoff, PRE-DEV BLDG B..............................................................
17
Hydrograph No.
4, SCS Runoff, POST-DEV BLDG B............................................................
18
Hydrograph No.
5, Reservoir, BLDG A - UGS ROUTE.........................................................
19
Hydrograph No.
6, Reservoir, BLDG B - UGS ROUTE..........................................................
20
5 - Year
SummaryReport
.......................................................................................................................
21
HydrographReports.................................................................................................................
22
Hydrograph No.
1, SCS Runoff, PRE-DEV BLDG A.............................................................
22
Hydrograph No.
2, SCS Runoff, POST-DEV BLDG A ...........................................................
23
Hydrograph No.
3, SCS Runoff, PRE-DEV BLDG B..............................................................
24
Hydrograph No.
4, SCS Runoff, POST-DEV BLDG B............................................................
25
Hydrograph No.
5, Reservoir, BLDG A - UGS ROUTE.........................................................
26
Hydrograph No.
6, Reservoir, BLDG B - UGS ROUTE..........................................................
27
10 -Year
SummaryReport
.......................................................................................................................
28
HydrographReports.................................................................................................................
29
Hydrograph No.
1, SCS Runoff, PRE-DEV BLDG A.............................................................
29
Hydrograph No.
2, SCS Runoff, POST-DEV BLDG A ...........................................................
30
Hydrograph No.
3, SCS Runoff, PRE-DEV BLDG B..............................................................
31
Hydrograph No.
4, SCS Runoff, POST-DEV BLDG B............................................................
32
Hydrograph No.
5, Reservoir, BLDG A - UGS ROUTE.........................................................
33
Hydrograph No.
6, Reservoir, BLDG B - UGS ROUTE..........................................................
34
OFReport.................................................................................................................. 35

CaIOEESIGN &
ENGINEERING, PLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
2537E. LYON STATION RD, STE 102
PO BOX 361
FILTERRA SCM
INFORMATION
CREEDMOOR, NC 27522
919-625-7368

Environmental
NCDEQ Stormwater Design Manual I C&
Quality
drainage areas that are larger, or not fully impervious, Contech Engineered Solutions can
prepare a custom sizing on a project specific basis to provide the most economical system
design.
Table 1. Filterra Sizing based on Withers & Ravene/ (2008) and NC Stormwater Rules
4x4
4x6 / 6x4
4x8 / 8x4
6x6
6x8 / 8x6 / 4x12 / 12x4
6x10 / 10x6
6x12 / 12x6
16
0.06
24
0.14
32
0.19
36
0.21
48
0.28
60
0.35
72
0.42
91
—
Other / Custom Sizes / TBD Media Area = 0.39%
Filterra Bioscape
1. Contact Contech for information on other available configurations.
2. A standard PVC coupling is cast into the wall to connect to discharge piping.
3. Dimensions shown are internal.
4" PVC
4" PVC
4" PVC
4" PVC
4" PVC
6" PVC
6" PVC
611�Fr-
TBD
MDC 2. PONDING DEPTH FOR DESIGN.
The ponding depth for the design water quality volume shall be 9 inches above the media
layer for standard designs.
Custom designs in coordination with Contech Engineered Solutions may vary.
MDC 3. UNDERDRAIN. For Filterra units up to 48 square feet in media surface area, a 4"
underdrain will be utilized. For larger surface areas (up to maximum standard sizes) a 6"
underdrain will be utilized.
The underdrain system is connected on outside of modular container by means of a PVC
coupler.
D-3. Filterra 5 Revised: 2-11-2018

CaIOEESIGN &
ENGINEERING, PLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
2537E. LYON STAT/ON RD, STE 102
PO BOX 361
CREEDMOOR, NC 27522
919-625-7368
POST DELINEATIONS OF
IMPERVIOUS AREAS

POST- IMPERVIOUS DELINEATIONS
2019-06-15 C EA
TOTAL PROPERTY AREA: ±1 01 7017 SF
TOTAL PROPOSED IMPERVIOUS AREA: ± 567123 SF (55.56%)
TOTAL INCREASE: 10,878 SF (24.10%)
±4,398 SF
BUILDING 1
±8,778 SF
BUILDING 2
U
255 SF
PICNIC
SHELTER
±25,213 SF
qG
SF
3 / PADS
1,858 SF
ILDING 3

CaIOEESIGN &
ENGINEERING, PLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
2537E. LYON STAT/ON RD, STE 102
PO BOX 361
CREEDMOOR, NC 27522
919-625-7368
INLET AREAS AND PIPE
CALCULATIONS

DRAINAGE AREA TO DWAY PIPE
IMPERVIOUS- 268 SF SF
TOTAL AREA= 2682 SF I
VY �
j , \
v�
DRAINAGE AREA TO ST \ /\ \ IMPERVIOUS SF
TOTAL AREA=21 924 SF \
DRAINAGE AREA TO ST-
I IMPERVIOUS= 7374 SF
TOTAL AREA =8]69 SF
� \ E
3 �� \
,
-` IMP
EfJAGE�4REA TO ST-1
\ \ IMPER`/IOL}� 500 SF (ALL` N )
/1A TOTAL
-DRX REA TO ST 4
PERVIOUS 5, 874 SF
TALAREA= 8SF
01
�\ �S 1 \ 4 `�• /� Ogg /Vo�/
/
—mz05 AID
�4
V�To--00 I �0
� 900
00
D@AILIAGE ARE O S /�' L� �A
—100 \ \ _ O IMPERV _ F -- �� / /1
\ j7osr % �100 00
99J \ \5� %1 0 / / o—/
%0
10 - '00
J\
9
INLET DELINEATIONS 3 g6
2019-06-17 C EA
96�
95`

Storm Sewer Profile
Proj. file: 2019-06-17 Parking Lot Drainage System.stm
Elev. (ft)
119.00
c
O M -
0
M M
o
o
O -o W
6 c j6
c
00
+
O
HMV
C, CO
�_{
WWW
E j j6
N
O c
o nub
�.0�
moo
+ WWW
j j0
CI)
c
OE
o00
�OM
Moo
CO
N WWW
j j
d
O
00
�(0
o0
CO WW
�0 j
119.00
115.00
111.00
115.00
111.00
107.00
107.00
103.00
103.00
-------- --
-
--
------
0
---- -- - ---
@ 0 • °
- 15"
79fiu
0/C
99.00
0 25 50 75 100
HGL EGL
125 150 175 200 225
Reach (ft)
99.00
250 275 300 325
Storm Sewers

Storm Sewer Profile
Proj. file: 2019-06-17 Parking Lot Drainage System.stm
Elev. (ft)
114.00
42
O o c
�
O Ocz�q
g w
o-ow
Cu E >
cn C7
LO
J �0
M O
O
CD
+ Ww
m E>
cn o s
114.00
110.00
106.00
110.00
106.00
-
`
102.00
98.00
94.00
-- 02.00
_ --- -- o
98.00
94.00
0 10 20 30 40 50 60 70 80 90 100 110
HGL EGL Reach (ft)
Storm Sewers

Line Profile (Line 1) - P1
Page 1 of 1
Line 1 - P1
EIew (ft)
105.O[}
105.00
.....................................
103.00
101.O[}
101.00
v
1 v 2 v-
4--
80 a 1 11D 120 130 140
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade Line
Velocity
Cover
Line #
Q
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
1
5.35
102.30
103.35
0.89
0.89
0.89
103.19
104.24
104.24
4.90
4.89
2.55
1.25
Project File:
No. Lines: 5
Run Date: 6/18/2019
Storm Sewers

Line Profile (Line 2) - P2
Page 1 of 1
Une 2
- P2
EIev (ft)
11 v.vv
11OM
ST-3
IT--2
1015.01)
106.OD
1 v .vv
...........
104.00
. .... _. .... _..............• ...
................
.7� �I
I rV
Linea
1 v..vv
Line, I
10.00
1 vv.vv
1 I}OM
v
5
16
16 2v.25 30
35v0
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade Line
Velocity
Cover
Line #
Q
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
2
4.34
103.45
104.05
0.79
0.84
0.84
104.24
104.89
104.89
5.30
4.93
1.40
2.10
Project File:
No. Lines: 5
Run Date: 6/18/2019
Storm Sewers

Line Profile (Line 3) - P3
Page 1 of 1
Line 3 - P3
Elev (ft)
109.0^-
107.M —
MEOW-
66 408E� - 15- @-U-. 98%
F—I
1 DiM
5 10 15
20 25 �O a5 40 45
F v
R r-60 65
70 75 80
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade Line
Velocity
Cover
Line #
Q
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
3
1.48
104.15
104.80
0.74
0.48
0.48
104.89
105.28 j
105.28
1.94
3.39
2.00
3.45
Project File:
No. Lines: 5
Run Date: 6/18/2019
Storm Sewers

Line Profile (Line 4) - P4
Page 1 of 1
Line 4
- N
109.()^- —
.
. . . ......... ......... ........... ...........
............ ........ ....
......
...........
. .... .......... ........... ..................
�l
69.000-f -1 F.
@
e3
1 v1.vv
1131M
15
20 25 30 35 40
45
50 FF 60 65
71D 75 80
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade Line
Velocity
Cover
Line #
Q
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
4
0.24
104.90
105.60
0.38
0.19
0.19
105.28
105.79 j
105.79
0.77
2.06
3.35
3.55
Project File:
No. Lines: 5
Run Date: 6/18/2019
Storm Sewers

Line Profile (Line 5) - OUTFALL 1 Page 1of1
Line 5 - OUTFALL I
El e+ (0)
1 1 v.vv
110.00
106.C-v
-
-
-
106.00
1 v.2.30
102.00
SIP
9G.00
94.00
9D.00
10 20 30 40 50
00 70 00
9D
100 110 120
130
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade
Line
Velocity
Cover
Line #
Q 10
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
5
5.68
97.50
102.10
0.53
0.92
0.92
98.03
103.02
103.02
10.16
5.01
-1.50
2.75
Project File:
No.
Lines: 5
Run Date: 6/18/2019
Storm Sewers

CaIOEESIGN &
ENGINEERING, PLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
MISC DATA:
2537E. LYON STATION RD, STE 102
PO BOX 361
CREEDMOOR, NC 27522
919-625-7368
-NOAA RAINFALL
CHARTS

NOAA Atlas 14, Volume 2, Version 3
' Location name: Siler City, North Carolina, USA*;
Latitude: 35.7229*, Longitude:-79.4702*
Elevation: 628.82 ft**
*source ESRI Maps'w
**source USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley
NOAA, National Weather Service, Silver Spring, Maryland
PF tabular I PF graphical I Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1
Average recurrence interval (years)
1 2 5 10 25 50 100 200 500 1000
0.417
0.494
0.573
0.627
0.686
0.724
0.759
0.787
0.817
0.837
5-min
(0.381-0.457)
(0.452-0.542)
(0.523-0.629)
(0.571-0.686)
(0.622-0.750)
(0.654-0.792)
(0.682-0.830)
(0.704-0.862)
(0.724-0.895)
(0.736-0.918)
0.666
0.790
0.917
1.00
1.09
1.15
1.21
1.25
1.29
1.32
10-min
(0.608-0.730)
(0.722-0.868)
(0.838-1.01)
(0.913-1.10)
(0.991-1.20)
1 (1.04-1.26)
1 (1.08-1.32)
1 (1.15-1.42) 11
(1.16-1.45)
15-min
0.832
(0.761-0.913)
0.994
(0.908-1.09)
1.16
1 (1.06-1.27)
1.27
1 (1.16-1.39)
1.39
1 (1.26-1.52)
1.46
1 (1.32-1.60)
1.52
1 (1.37-1.67)
1.57
1.63
1 (1.44-1.78)
1.65
(1.45-1.81)
30-min
1.14
(1.04-1.25)
1.37
1 (1.25-1.51)
1.65
1 (1.51-1.81)
1.84
1 (1.67-2.01)
2.05
1 (1.86-2.25)
2.20
1 (1.99-2.41)
2.33
1 (2.10-2.55)
2.45
2.59
1 (2.29-2.84)
2.68
(2.36-2.94)
60-min
1.42
(1.30-1.56)
1.72
1 (1.57-1.89)
2.11
1 (1.93-2.32)
2.39
1 (2.18-2.62)
F 2.98
1 (2.69-3.26) 11
3.22
(2.89-3.52)
3.44
1 (3.07-3.76)
3.71
1 (3.29-4.07)
3.91
1 (3.44-4.29)
2-hr
1.70
(1.55-1.88)
2.07
1 (1.89-2.28)
2.56
1 (2.33-2.82)
2.92
1 (2.65-3.22)
3.38
1 (3.05-3.72)
3.72
1 (3.34-4.09)
4.06
1 (3.62-4.46)
4.38
1 (3.88-4.82)
4.80
1 (4.21-5.28)
5.12
1 (4.45-5.65)
1.82
2.21
2.75
3.15
3.67
4.07
4.47
4.86
5.39
5.81
3-hr
(1.66-2.00)
(2.02-2.43)
1 (2.51-3.02)
1 (2.87-3.45)
1 (3.32-4.02)
1 (3.66-4.46)
1 (3.98-4.89)
1 (4.31-5.33)
1 (4.72-5.91)
(5.02-6.38)
6-hr
0
EGG
a
7.
(5.3616.56)
(5. 6774.35)
(6. 83.98)
2.60
3.14
3.93
4.55
5.40
6.07
6.77
7.50
8.51
9.32
12-hr
(2.38-2.84)
1 (2.89-3.45)
1 (3.60-4.31)
1 (4.15-4.98)
1 (4.88-5.88)
1 (5.45-6.60)
1 (6.01-7.35)
1 (6.58-8.13)
(7.34-9.23)
(7.92-10.1)
6
(7. 6 9420)
(8. 4--10.4)
(9.60-11.4)
2-day
3.51
(3.29-3.76)
4.22
(3.96-4.53)
5.25
(4.92-5.63)
6.04
(5.64-6.48)
7.11
(6.62-7.64)
7.95
(7.38-8.54) A(8.15-9.49)
8.82
9.70
(8.95-10.5)
10.9
(10.0-11.8)
11.9
(10.8-12.9)
3-day
3.72
(3.49-3.99)
4.47
(4.19-4.80)
5.53
(5.18-5.93)
6.36
(5.94-6.82)
7.48
1 (6.96-8.02)
8.37
(7.75-8.97)
9.27
1 (8.56-9.96)
10.2
(9.40-11.0)
11.5
(10.5-12.4)
12.5
(11.4-13.5)
4-day
3.94
(3.69-4.22)
4.72
(4.42-5.06)
5.82
(5.44-6.23)
6.68
(6.23-7.15)
7.85
(7.29-8.41)
8.78
(8.13-9.40)
9.72
(8.98-10.4)
10.7
(9.85-11.5)
12.1
(11.0-13.0)
13.1
(11.9-14.2)
7-day
4.52
(4.26-4.83)
5.40
(5.07-5.76)
6.56
(6.16-7.00)
7.49
(7.02-7.99)
8.75
(8.18-9.35)
9.76
(9.08-10.4)
10.8
(9.99-11.5)
11.8
(10.9-12.7)
13.3
(12.2-14.3)
14.5
(13.2-15.6)
10tlay 5.15 6.12 7.35 8.32 9.63 10.7 11.7 12.8 14.2 15.3
(4.86-5.48) (5.77-6.52) 1 (6.92-7.83) 1 (7.82-8.87) (9.01-10.3) 1 (9.94-11.4) 1 (10.9-12.5) (11.8-13.6) 1 (13.1-15.2) 1 (14.1-16.5)
20tlay 6.92 8.16 9.64 10.8 12.4 13.6 14.9 16.2 17.9 19.3
(6.54-7.31) (7.73-8.62) 1 (9.11-10.2) 1 (10.2-11.4) 1 (12.8-14.4) (13.9-15.8) 1 (16.6-19.1) (17.8-20.6)
30tlay 8.57 10.1 11.7 13.0 14.7 16.0 17.2 18.5 20.2 21.6
(8.17-9.02) (9.60-10.6) 1 (11.1-12.3) 1 (12.3-13.7) 1 (15.1-16.8) (16.2-18.2) 1 (17.4-19.6) 1 (18.9-21.4) 1 (20.1-22.9)
45tlay 10.9 12.8 14.6 16.1 17.9F 19.3 20.7 22.1 23.9 25.3
(10.4-11.5) (12.2-13.4) 1 (13.9-15.3) 1 (15.3-16.8) (17.0-18.8) (18.3-20.3) A (19.6-21.8) 1 (22.5-25.2) (23.7-26.7)
60tlay 13.1 15.2 17.2 18.7 20.7 22.2 23.6 25.0 26.8 28.1
(12.5-13.7) (14.6-16.0) (16.5-18.0) (17.9-19.6) (19.7-21.7) (21.1-23.2) (22.4-24.8) (23.7-26.2) (25.3-28.2) (26.5-29.7)
Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90 % confidence interval. The probability that precipitation frequency estimates (for
a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not
checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values.
Please refer to NOAAAtlas 14 document for more information.
Back to Top

c
.�u
25
5
0
PF graphical
PD5-based depth -duration -frequency {DDT} curves
Latitude: 35.7229', Longitude:-79.4702'
E
1=
1=
E
E
-0 -0-0
-0 -0
-0 -0
-0-0
u'S
61A
Q
O
A rh
Lb A
�" 1
f+l
A f� V
fM1 6
OO O
LA 6rl
rl
m
lG
'-I
N rn
r km
Duration
30
25
a
r 20
0
1 2 5 10 25 50 100 200 500 1000
Average recurrence interval (years)
NQAA Atlas 14, Volume 2, Version 3 Created {GMTY Thu May 2 22:44:24 2019
Back to Top
Average recurrence
interval
(years)
— 1
2
5
10
25
50
100
200
500
1000
Duration
— 5-min —
2-day
— 10-min —
3-day
15-min —
4-day
— 3Dfnin —
7-day
— 6D�rnin —
1 0-day
— 2fir —
20-day
— "r —
30-day
— 8-rr —
45-day
— 12-hr —
60-day
— 24-hr

Maps & aerials
Small scale terrain
� Siler City
J.
5ltF.R
❑ zr .YUM
J }11.Rp 0.R7
L.
ii
a
3km
mi
Large scale terrain
l
i
Winston-Salem
• • Durham
�
Greenshoral Raleigh ' Rocky Mi
NORTH CAROLIAA •'
'Charlotte Fayetteville;
Je
e 1001km '
1 i,;AL a n,I IT T 11 a ,.
Large scale map
inston-TalerrvGreensboro
Durham
oRoky Mr
Raleigh
Y I+rth
Carolina
art Otte
F W ettevi I l e
.r
1001km
60mi

Back to Top
US Department of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
National Water Center
1325 East West Highway
Silver Spring, MD 20910
Questions?: HDSC.Questionsidnoaa.aov
Disclaimer

NOAA Atlas 14, Volume 2, Version 3
' Location name: Siler City, North Carolina, USA*;
Latitude: 35.7229*, Longitude:-79.4702*
Elevation: 628.82 ft**
*source ESRI Maps'w
**source USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley
NOAA, National Weather Service, Silver Spring, Maryland
PF tabular I PF graphical I Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1
Average recurrence interval (years)
Duration 1 100 1 2 5 10 25 50 00 200 500 1000
9.10-min
0.0)
(8.45410.3)
(8.69$ 0.7)
(8.80
4.00
4.74
5.50
6.02
6.56
6.92
7.24
7.48
7.75
7.91
(3.65-4.38)
1 (4.33-5.21)
1 (5.03-6.04)
1 (5.48-6.59)
(5.95-7.18)
1 (6.25-7.57)
(6.50-7.91)
(6.70-8.20)
(6.87-8.49)
1 (6.95-8.67)
15-min
1
2-5.
(4.62-5.56)
5.54
(5.02-6.06)
(�3)
6.10
(5.48-6.6.
6.30
(5.63-6.90)
6.50
(5.76-7.12)
6.62
(5.82-7.26)
�)
(�
(3.35-4.02)
54
�3)
(�
4.20-5.
i i�
4.90
(4.38-5.37)
5.17
(4.59-5.67)
5.36
(4.71-5.87)
AEG
11
(3.074476)
1 (3.29 4..07)
(3.44 4129)
0.852
1.03
1.28
1.46
1.69
1.86
2.03
2.19
2.40
2.56
2-hr
(0.777-0.939)
(0.944-1.14)
1 (1.17-1.41)
1 (1.33-1.61)
1 (1.53-1.86)
1 (1.67-2.05)
(1.81-2.23)
(1.94-2.41)
(2.11-2.64)
(2.22-2.82)
0.606 1
F 0.736 1
F 0.914
1.05
1.22
1.36
1.49
1.62
1.80
1.93
3-hr
(0.554-0.666)
(0.673-0.810)
(0.834-1.00)
(0.954-1.15)
1 (1.22-1.48)
(1.33-1.63)
1 (1.43-1.77)
1 (1.57-1.97)
1 (1.67-2.12)
0.365
0.443
0.551
0.633
0.744
0.830
0.917
1.00
1.13
1.22
6-hr
(0.335-0.401)
(0.407-0.485)
(0.504-0.603)
(0.578-0.692)
(0.673-0.811)
(0.746-0.904)
(0.818-0.999)
(0.887-1.10)
(0.979-1.23)
(1.05-1.33)
0.215
0.261
0.326
0.378
0.448
0.504
0.562
0.622
0.706
0.774
12-hr
(0.198-0.236)
(0.240-0.286)
(0.299-0.357)
(0.344-0.413)
(0.405-0.488)
(0.452-0.548)
(0.499-0.610)
(0.546-0.675)
(0.609-0.766)
(0.657-0.839)
0.125
0.150
0.188
0.218
0.258
0.290
0.322
0.356
0.402
0.439
24-hr
(0.116-0.134)
(0.141-0.161)
(0.176-0.202)
(0.203-0.234)
(0.240-0.277)
(0.268-0.311)
(0.298-0.347)
(0.328-0.383)
(0.368-0.434)
(0.400-0.474)
0.073
0.088
0.109
0.126
0.148
0.166
0.184
0.202
0.227
0.247
2-day
(0.068-0.078)
(0.082-0.094)
(0.102-0.117)
(0.118-0.135)
(0.138-0.159)
(0.154-0.178)
(0.170-0.198)
(0.186-0.218)
(0.208-0.246)
(0.226-0.268)
0.052
0.062
0.077
0.088
0.104
0.116
0.129
0.142
0.160
0.174
3-day
(0.048-0.055)
(0.058-0.067)
(0.072-0.082)
(0.082-0.095)
(0.097-0.111)
(0.108-0.125)
(0.119-0.138)
(0.130-0.153)
(0.146-0.172)
(0.158-0.188)
0.041
0.049
0.061
0.070
0.082
0.091
0.101
0.112
0.126
0.137
4-day
(0.038-0.044)
(0.046-0.053)
(0.057-0.065)
(0.065-0.074)
(0.076-0.088)
(0.085-0.098)
(0.093-0.109)
(0.103-0.120)
(0.115-0.135)
(0.124-0.147)
0.027
0.032
0.039
0.045
0.052
0.058
0.064
0.071
0.079
0.086
7-day
(0.025-0.029)
(0.030-0.034)
(0.037-0.042)
(0.042-0.048)
(0.049-0.056)
(0.054-0.062)
(0.059-0.069)
(0.065-0.076)
(0.073-0.085)
(0.079-0.093)
10tlay 0.021 0.026 0.031 0.035 0.040 0.044 0.049 0.053 0.059 0.064
(0.020-0.023) (0.024-0.027) (0.029-0.033) (0.033-0.037) (0.038-0.043) (0.041-0.047) (0.045-0.052) (0.049-0.057) (0.055-0.063) (0.059-0.069)
20tlay 0.014 0.017 0.020 0.023 0.026 0.028 0.031 0.034 0.037 0.040
(0.014-0.015) (0.016-0.018) (0.019-0.021) (0.021-0.024) (0.024-0.027) (0.027-0.030) (0.029-0.033) (0.031-0.036) (0.035-0.040) (0.037-0.043)
30tlay 0.012 0.014 0.016 0.018 0.020 0.022 0.024 0.026 0.028 0.030
(0.011-0.013) (0.013-0.015) (0.015-0.017) (0.017-0.019) (0.019-0.021) (0.021-0.023) (0.023-0.025) (0.024-0.027) (0.026-0.030) (0.028-0.032)
45tlay 0.010 0.012 0.014 0.015 0.017 0.018 0.019 0.020 0.022 0.023
(0.010-0.011) (0.011-0.012) (0.013-0.014) (0.014-0.016) (0.016-0.017) (0.017-0.019) (0.018-0.020) (0.019-0.022) (0.021-0.023) (0.022-0.025)
60tlay 0.009 0.011 0.012 0.013 0.014 0.015 0.016 0.017 0.019 0.020
(0.009-0.009) (0.010-0.011) (0.011-0.013) (0.012-0.014) (0.014-0.015) (0.015-0.016) (0.016-0.017) (0.016-0.018) (0.018-0.020) (0.018-0.021)
Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90 % confidence interval. The probability that precipitation frequency estimates (for
a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not
checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values.
Please refer to NOAAAtlas 14 document for more information.
Back to Top

PF graphical
PDS-based intensity -duration -frequency (IDF) curves
Latitude: 35.7229", Longitude:-79.4702"
100-000
_ ......:. ........................... .
rf ORS
C_ C_ G G C_ - - 7, 7, 1., }, 7, 7, y, }, 1.,E E E E E A rh A a � fl
u'S O 111 Q OO �"� f+l A r6 V M1 O O O Ln O
Duration O
rl •i m lG '-I N rn r km
100000
r
10-000
G
ZI
L+ 1-000
c
v
G
0.001 1 ' ' ' ' ' ' ' ' a
1 2 5 10 25 50 100 200 500 1000
Average recurrence interval (years)
NQAA Atlas 14, Volume 2, Version 3 Created (GMT): Thu May 2 22:45:20 2019
Back to Top
Average recurrence
interval
(years)
— 1
2
5
10
25
50
100
200
500
1000
Duration
— 5-min —
2-day
— 10-min —
3-day
15-min —
4-day
— 3Dfnin —
7-day
— 6D�rnin —
1 0-day
— 2fir —
24-day
— "r —
30-day
— 8-rr —
45-day
— 12-hr —
60-day
— 24-hr

Maps & aerials
Small scale terrain
� Siler City
J.
5ltF.R
❑ zr .YUM
J }11.Rp 0.R7
L.
ii
a
3km
mi
Large scale terrain
l
i
Winston-Salem
• • Durham
�
Greenshoral Raleigh ' Rocky Mi
NORTH CAROLIAA •'
'Charlotte Fayetteville;
Je
e 1001km '
1 i,;AL a n,I IT T 11 a ,.
Large scale map
inston-TalerrvGreensboro
Durham
oRoky Mr
Raleigh
Y I+rth
Carolina
art Otte
F W ettevi I l e
.r
1001km
60mi

Back to Top
US Department of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
National Water Center
1325 East West Highway
Silver Spring, MD 20910
Questions?: HDSC.Questionsidnoaa.aov
Disclaimer

Ca�OEESIGN &
ENGINEERING, PLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
2537E. LYON STAT/ON RD, STE 102
PO BOX 361
CREEDMOOR, NC 27522
919-625-7368
NCDOT HYDRAULIC.
CALCULATIONS:
- DRIVEWAY PIPE RUNOFF
- DRIVEWAY PIPE SIZING
- UGS DISCHARGE RATES AT
NORTH FIR AVENUE
-OUTFACE (P-5) DISCHARGE
RATES AT NORTH FIR
AVENUE
8

Hydrology Report
Hydraflow Express Extension for AUtodeskS AutoCADO Civil 31DO by Autodesk, Inc.
SILER SQUARE - DRIVEWAY PIPE
Tuesday, Jun 18 2019
Hydrograph type
= Rational
Peak discharge (cfs)
= 0.396
Storm frequency (yrs)
= 10
Time interval (min)
= 1
Drainage area (ac)
= 0.070
Runoff coeff. (C)
= 0.78
Rainfall Inten (in/hr)
= 7.246
Tc by User (min)
= 5
OF Curve
= 2019-05-20 Siler City NC
- Siler SRl9cd fad@W
= 1.00
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0 00
Runoff Hydrograph
10-yr frequency
Hydrograph Volume = 119 (cuft); 0.003 (acft)
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0 00
0 5 10
Time (min)
— Runoff Hyd - Qp = 0.40 (cfs)

Culvert Report
Hydraflow Express Extension for AUtodeskS AutoCADO Civil 31DO by Autodesk, Inc. Tuesday, Jun 18 2019
SILER SQUARE - DRIVEWAY PIPE
Invert Elev Dn (ft)
= 109.00
Calculations
Pipe Length (ft)
= 70.00
Qmin (cfs)
= 0.40
Slope (%)
= 0.36
Qmax (cfs)
= 0.40
Invert Elev Up (ft)
= 109.25
Tailwater Elev (ft)
= (dc+D)/2
Rise (in)
= 15.0
Shape
= Circular
Highlighted
Span (in)
= 15.0
Qtotal (cfs)
= 0.40
No. Barrels
= 1
Qpipe (cfs)
= 0.40
n-Value
= 0.012
Qovertop (cfs)
= 0.00
Culvert Type
= Circular Concrete
Veloc Dn (ft/s)
= 0.52
Culvert Entrance
= Groove end projecting (C)
Veloc Up (ft/s)
= 2.35
Coeff. K,M,c,Y,k
= 0.0045, 2, 0.0317, 0.69, 0.2
HGL Dn (ft)
= 109.75
HGL Up (ft)
= 109.50
Embankment
Hw Elev (ft)
= 109.58
Top Elevation (ft)
= 112.00
Hw/D (ft)
= 0.26
Top Width (ft)
= 42.00
Flow Regime
= Inlet Control
Crest Width (ft)
= 20.00
Elev (ft)
113.00
112.00
loom
110m
SILER SQUARE - DRIVEWAY PIPE
Hw Depth (ft)
3.75
2.75
IFNI
0.75
-0.25
1 N.04 i i i i i i i i i i i i i i i i i i i-1.25
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 S0 85 96
CircalarCulvert HGL Embank
Reach (ft)

1
Watershed Model Schematic Hydraflow Hydrographs Extension for Autodesk@ Civil 3D& 2019 by Autodesk, Inc. v202O
PRE-DEV BLDG A
-COST-DEV BLDG A
PRE-DEV BLDG BPOST-DEV BLDG B
r
r
5 - BLDG A - UGS ROUTE
6
- BLDG B - UGS ROUTE
Legend
Hid. Origin Description
1 SCS Runoff PRE-DEV BLDG A
2 SCS Runoff POST-DEV BLDG A
3 SCS Runoff PRE-DEV BLDG B
4 SCS Runoff POST-DEV BLDG B
5 Reservoir BLDG A- UGS ROUTE
6 Reservoir BLDG B - UGS ROUTE
Project: 2019-06-17 SILER PRE -POST
- INCREASE ONLY.gpw
Tuesday, 06 / 18 / 2019

Hydrograph Return Period Recap
Hydra w Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
Hydrograph
Inflow
Peak Outflow (cfs)
Hydrograph
No.
type
hyd(s)
Description
(origin)
1-yr
2-yr
3-yr
5-yr
10-yr
25-yr
50-yr
100-yr
1
SCS Runoff
------
0.125
0.197
-------
0.313
0.412
0.549
0.662
-------
PRE-DEV BLDG A
2
SCS Runoff
------
0.438
0.531
-------
0.666
0.773
0.917
1.030
-------
POST-DEV BLDG A
3
SCS Runoff
------
0.238
0.375
-------
0.594
0.782
1.044
1.257
-------
PRE-DEV BLDG B
4
SCS Runoff
------
0.833
1.009
-------
1.265
1.470
1.742
1.957
-------
POST-DEV BLDG B
5
Reservoir
2
0.122
0.142
-------
0.293
0.702
-------
BLDG A- UGS ROUTE
6
Reservoir
4
0.231
0.303
-------
0.592
i
-------
BLDG B - UGS ROUTE
Proj. file: 2019-06-17 SILER PRE -POST - INCREASE ONLY.gpw
Tuesday, 06 / 18 / 2019

Hydrograph Summary Repo rtH
ydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
0.412
1
718
827
------
------
------
PRE-DEV BLDG A
2
SCS Runoff
0.773
1
717
1,869
------
------
------
POST-DEV BLDG A
3
SCS Runoff
0.782
1
718
1,571
------
------
------
PRE-DEV BLDG B
4
SCS Runoff
1.470
1
717
3,551
------
------
------
POST-DEV BLDG B
5
Reservoir
M11
1
722
1,867
2
105.46
493
BLDG A - UGS ROUTE
6
Reservoir
WS2
_9%
722
3,550
4
101.51
930
BLDG B - UGS ROUTE
2019-06-17 SILER PRE -POST - INCREASE
Tuesday, 06 / 18 / 2019

Hydrograph Summary Repo rtH
ydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
0.549
1
718
1,107
------
------
------
PRE-DEV BLDGA
2
SCS Runoff
0.917
1
717
2,228
------
------
------
POST-DEV BLDG A
3
SCS Runoff
1.044
1
718
2,103
------
------
------
PRE-DEV BLDG B
4
SCS Runoff
1.742
1
717
4,233
------
------
------
POST-DEV BLDG B
5
Reservoir
�.�
1
721
2,226
2
105.87
551
BLDG A - UGS ROUTE
6
Reservoir
1
720
4,232
4
101.97
995
BLDG B - UGS ROUTE
2019-06-17 SILER PRE -POST - INCREASE
Tuesday, 06 / 18 / 2019

Hydrograph Summary Repo rtH
ydraflow Hydrographs Extension for Autodesk@ Civil 3D@ 2019 by Autodesk, Inc. v2020
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
0.662
1
718
1,339
------
------
------
PRE-DEV BLDG A
2
SCS Runoff
1.030
1
717
2,512
------
------
------
POST-DEV BLDG A
3
SCS Runoff
1.257
1
718
2,544
------
------
------
PRE-DEV BLDG B
4
SCS Runoff
1.957
1
717
4,773
------
------
------
POST-DEV BLDG B
5
Reservoir
Iowa,
1
719
2,510
2
105.96
557
BLDG A - UGS ROUTE
6
Reservoir
1
718
4,772
4
102.01
1,003
BLDG B - UGS ROUTE
2019-06-17 SILER PRE -POST - INCREASE
Tuesday, 06 / 18 / 2019

Hydraflow Rainfall Report
Hydraflow Hydrographs Extension for Autodeskg Civil 3DO 2019 by Autodesk, Inc. v2020 Tuesday, 06 / 18 / 2019
Return
Period
Intensity -Duration -Frequency Equation Coefficients (FHA)
(Yrs)
B
D
E
(NIA)
1
63.8568
12.6000
0.8882
--------
2
73.1817
12.7000
0.8750
--------
3
0.0000
0.0000
0.0000
--------
5
79.8313
13.1000
0.8465
--------
10
77.3185
12.7000
0.8111
--------
25
64.6079
11.1000
0.7420
--------
50
58.1851
10.2000
0.6990
--------
100
50.8258
9.0000
0.6516
--------
File name: 2019-05-20 NOAA IDF - SILER CITY.IDF
Intensity = B / (Tc + D)^E
Return
Period
Intensity Values (in/hr)
(Yrs)
5 min
10
15
20
25
30
35
40
45
50
55
60
1
5.00
4.00
3.35
2.89
2.55
2.28
2.07
1.89
1.74
1.62
1.51
1.42
2
5.92
4.76
4.00
3.46
3.06
2.74
2.49
2.28
2.11
1.96
1.83
1.72
3
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
5
6.88
5.60
4.74
4.13
3.66
3.30
3.01
2.77
2.56
2.39
2.24
2.11
10
7.52
6.14
5.23
4.57
4.07
3.68
3.36
3.10
2.88
2.69
2.53
2.39
25
8.22
6.72
5.74
5.04
4.51
4.10
3.77
3.49
3.25
3.05
2.88
2.73
50
8.68
7.12
6.10
5.37
4.83
4.40
4.05
3.77
3.53
3.32
3.14
2.98
100
9.10
7.46
6.41
5.66
5.11
4.67
4.32
4.02
3.78
3.57
3.38
3.22
Tc = time in minutes. Values may exceed 60.
D HOME\SILER SCHOOL 5-20\CIVIL-18-023\Desian\Stormwater\Hvdraflow\2019-05-20 NOAA PCP - SILER CITY.DCD
Storm
Rainfall Precipitation Table (in)
Distribution
1-yr
2-yr
3-yr
5-yr
10-yr
25-yr
50-yr
100-yr
SCS 24-hour
2.99
3.61
0.00
4.51
5.23
6.19
6.95
7.74
SCS 6-Hr
2.19
2.65
0.00
3.30
3.79
4.45
4.97
5.49
Huff-1 st
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-2nd
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-3rd
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-4th
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-Indy
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Custom
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00

Line Profile (Line 5) - OUTFALL 1 Page 1of1
Line 5 - OUTFALL I
El e+ (0)
1 1 v.vv
110.00
106.C-v
-
-
-
106.00
1 v.2.30
102.00
SIP
9G.00
94.00
9D.00
10 20 30 40 50
00 70 00
9D
100 110 120
130
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade
Line
Velocity
Cover
Line #
Q 10
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
5
5.68
97.50
102.10
0.53
0.92
0.92
98.03
103.02
103.02
10.16
5.01
-1.50
2.75
Project File:
No.
Lines: 5
Run Date: 6/18/2019
Storm Sewers

Line Profile (Line 5) - OUTFALL 1 Page 1of1
Line 5 - OUTFALL I
El e+ (ft)
1 1 v.vv
110.00
106.C-v
-
-
-
-
106.00
............
9G.00
. v v
94.00
10 20 30 40 50
60 70 so
9D
100 110 120
130
req-lfn
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade
Line
Velocity
Cover
Line # Q 25
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
5 L6.31
97.50
102.10
0.58
0.97
0.97
98.08
103.07
103.07
10.00
5.22
-1.50
2.75
Project File:
--
No.
Lines: 5
Run Date: 6/18/2019
Storm Sewers

Line Profile (Line 5) - OUTFALL 1 Page 1of1
Line 5 - OUTFALL I
El e+ (0)
1 1 v.vv
110.00
106.C-v
-
-
-
-
106.00
1 v2.30
102.00
............
vv.v0
-.00
94.00
9D.00
10 20 30 40 50
00 70 00
9D
100 110 120
130
Reach (ft)
Invert Elevation
Depth of Flow
Hydraulic Grade
Line
Velocity
Cover
Line #
Q50
Dn
Up
Dn
Up
Hw
Dn
Up
Jnct
Dn
Up
Dn
Up
(cfs)
(ft)
i
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft/s)
(ft/s)
(ft)
(ft)
5
6.73
- -
97.50
102.10
0.58
1.00
1.00
98.08
103.10
103.10
10.67
5.36
-1.50
2.75
Project File:
FNo.
Lines: 5
Run Date: 6/18/2019
Storm Sewers