20180001 Ver 1_Stormwater Impact Analysis_20180511

Aberdeen Transmission HQ
Stormwater Impact Analysis & Design of Stormwater Management Facility
1
Aberdeen Transmission HQ
Stormwater Impact Analysis & Design of Stormwater Management Facility
General Description
Located to the west of Allison Page Road off NC Highway 5, in Aberdeen, North Carolina, is the
proposed commercial development currently known as Aberdeen Transmission HQ. Proposed
development on this site will consist of the construction of a fleet garage and a transmission HQ
building, along with associated parking lot, utility, and stormwater management improvements.
The proposed development is in Moore county within the Lumber river basin, and drains into a
tributary to Aberdeen Creek. Per Town of Aberdeen regulations, stormwater management on this
site shall meet the stormwater management performance standards for development set forth in
the Town of Aberdeen Ordinance. These are as follows:
Article XVI. Sec. 152-263. Stormwater Management.
(A)All development shall be constructed and maintained so that adjacent properties
are not unreasonably burdened with surface waters as a result of such
developments. More specifically:
(1)No development may be constructed or maintained so that such
development unreasonably impedes the natural flow of water from
higher adjacent properties across such development, thereby
unreasonably causing substantial damage to such higher adjacent
properties; and Article XVI – Floodways, Floodplains, Drainage and
Erosion 32 of 34
(2)No development may be constructed or maintained so that surface
waters from such development are unreasonably collected and
channeled onto lower adjacent properties at such locations or at such
volumes as to cause substantial damage to such lower adjacent
properties.
(B)The development site plan must provide plans for stormwater management. The
stormwater plan must address hydrology, low-impact development design
strategies and erosion sediment control.
To meet the above standard, a stormwater management facility is proposed. Please refer to the
appropriate section of this report for additional information.
Calculation Methodology
•Using maps contained within the Moore County Soil Survey, the on-site soils were
determined to be from hydrologic soil group (HSG) ‘A’ and ‘C’ soils. Since the method
chosen to compute pre- and post-development peak flow rates and runoff volumes is
dependent upon the soil type, care was taken when selecting the appropriate Soil
Conservation Service Curve Number (SCS CN). A composite SCS CN was computed for
each pre- and post-development sub-basin.
•The time of concentration was calculated using SCS TR-55 (Segmental Approach, 1986).
The Tc flow path was divided into three segments: overland flow, concentrated flow, and
channel flow. The travel time was then computed for each segment, from which the
overall time of concentration was determined by taking the sum of each segmental time.
2
•The topography for the pre-development analysis is based on a recent field survey
performed by The John R. McAdams Company, Inc. and available Moore County GIS
data.
•The post-development cover conditions were determined from the proposed construction
drawings.
•The proposed stormwater management facility was designed in accordance with the
North Carolina design standards.
Discussion of Results
The proposed improvements onsite result in an increase of approximately 3 acres of impervious
area. A portion of the site drainage is collected and directed to a dry pond to mitigate the impact
of increased flows leaving the site.
Conclusion
If the development on this tract is built as proposed within this report, then the requirements set
forth in Town of Aberdeen regulations will be met without additional stormwater management
facilities. However, modifications to the proposed development may require that this analysis be
revised. Some modifications that would require this analysis to be revised include:
1.The proposed site impervious surface exceeds the amount accounted for in this report.
2.The post-development watershed breaks change significantly from those used to prepare
this report.
The above modifications may result in the assumptions within this report becoming invalid. The
computations within this report will need to be revisited if any of the above conditions become
apparent as development of the proposed site moves forward.
7 STORMWATER MANAGEMENT
FACILITY DESIGN CALCULATIONS
1 SUMMARY OF RESULTS
2
MISCELLANEOUS SITE
INFORMATION
6
POST-DEVELOPMENT
HYDROLOGIC CALCULATIONS
5
PRE-DEVELOPMENT HYDROLOGIC
CALCULATIONS
3 WATERSHED SOILS INFORMATION
4 PRECIPITATION DATA
ABERDEEN TRANSMISSION HQ
DKE-17280
SUMMARY OF RESULTS
Project Name: Aberdeen Transmission HQ Date: 4/19/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
RELEASE RATE MANAGEMENT RESULTS
Pre-Dev Post-Dev
Return Period [cfs][cfs]% Increase
1-Year 0.72 0.50 -31%
2-Year 1.32 0.82 -38%
10-Year 2.89 1.64 -43%
25-Year 3.81 2.11 -45%
Pre-Dev Post-Dev
Return Period [cfs][cfs]% Increase
1-Year 3.86 2.86 -26%
2-Year 6.55 3.76 -43%
10-Year 13.73 5.56 -60%
25-Year 18.53 13.72 -26%
Pre-Dev Post-Dev
Return Period [cfs][cfs]% Increase
1-Year 0.04 0.09 125%
2-Year 0.23 0.23 0%
10-Year 1.59 0.72 -55%
25-Year 2.92 1.03 -65%
SUMMARY OF RESULTS
POINT OF ANALYSIS #1
POINT OF ANALYSIS #2
POINT OF ANALYSIS #3
Project Name: Aberdeen Transmission HQ Date:3/14/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
STORMWATER MANAGEMENT FACILITY SUMMARY
Design Drainage Area =10.16 acres
Design Impervious Area =7.25 acres
% Impervious =71.4%
Top of Dam =430.00 ft
Orifice =10.00 in
Orifice Elevation =422.25 ft
Spillway =10.00 ft
Spillway Elevation =428.75 ft
Barrel Diameter =15 in
Invert In =422.25 ft
Invert Out =422.00 ft
Length =50 ft
% Slope =0.50%
STORMWATER MANAGEMENT FACILITY ROUTING RESULTS
Inflow Outflow Max WSE Freeboard
Return Period [cfs][cfs][ft][ft]
1-Year 24-Hour 24.12 2.82 425.07 4.93
2-Year 32.86 3.68 425.88 4.12
10-Year 52.30 5.42 428.19 1.81
25-Year 63.22 13.51 429.15 0.85
50-Year 71.44 23.93 429.46 0.54
100-Year 79.49 30.82 429.63 0.37
SUMMARY OF RESULTS
ABERDEEN TRANSMISSION HQ
DKE-17280
MISCELLANEOUS SITE INFORMATION
Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors
0 400 800200Feet1 inch = 400 feet
¯ABERDEEN TRANSMISSION HQ
SITE AERIAL MAPPROJECT #: DKE-17280ABERDEEN, NORTH CAROLINA
Copyright:© 2013 National Geographic Society, i-cubed
0 2,000 4,0001,000 Feet1 inch = 2,000 feet
¯ABERDEEN TRANSMISSION HQ
USGS TOPO MAPPROJECT #: DKE-17280ABERDEEN, NORTH CAROLINA
Legend
Cross-Sections
Base Flood Elevations
Flood Hazard Zones
1% Annual Chance Flood
Regulatory Floodway
Special Floodway
Area of Undetermined Flood Hazard
0.2% Annual C hance Flood
Future C onditions 1% Annual ChanceFlood H azard
Area with R educed Risk Due to Levee
LO MRs
Effective
Map Panels
Digital Data
Unmodernized Maps
Unmapped
USGS The National Map: Orthoimagery
National Flood Hazard Layer FIRMette
0 500 1,000 1,500 2,000250Feet
Ü79°27'17.57"W 35°8'42.03"N 79°26'38.60"W 35°8'11.42"N Date: 8/16/2017 Tim e: 4:04:37 PM
This map complies with FEMA’s standards for the use ofdigital flood maps. The flood hazard information isderived directly from the authoritative NFHL web servicesprovided by FEMA. The base map shown complies withFEMA’s base map accuracy standards.
The NFHL is a living database, updated daily, and thismap represents a snapshot of information at a specifictime.
Flood risks are dynamic and can change frequently due toa variety of factors, including weather patterns, erosion,and new development. FEMA flood maps are continuallyupdated through a variety of processes. Users shouldalways verify through the Map Service Center(http://msc.fema.gov) or the Community Map Repositorythat they have the current effective information.
NFH L maps should not be created for unmapped orunmodernized areas.
ABERDEEN TRANSMISSION HQ
DKE-17280
WATERSHED SOILS INFORMATION
Hydrologic Soil Group—Moore County, North Carolina
(Property Line)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
8/16/2017
Page 1 of 43889520388958038896403889700388976038898203889880388994038895203889580388964038897003889760388982038898803889940641100641160641220641280641340641400
641100 641160 641220 641280 641340 641400
35° 8' 33'' N 79° 27' 5'' W35° 8' 33'' N79° 26' 51'' W35° 8' 18'' N
79° 27' 5'' W35° 8' 18'' N
79° 26' 51'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 17N WGS84
0 100 200 400 600
Feet
0 30 60 120 180
Meters
Map Scale: 1:2,330 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Rating Polygons
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Lines
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Points
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Moore County, North Carolina
Survey Area Data: Version 18, Sep 20, 2016
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Aug 13, 2014—Feb
4, 2017
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Hydrologic Soil Group—Moore County, North Carolina
(Property Line)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
8/16/2017
Page 2 of 4
Hydrologic Soil Group
Hydrologic Soil Group— Summary by Map Unit — Moore County, North Carolina (NC125)
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
AeB Ailey loamy sand, 2 to 8
percent slopes
A 12.8 59.0%
CaB Candor sand, 0 to 4
percent slopes
A 5.3 24.6%
GhD Gilead loamy sand, 8 to
15 percent slopes
C 3.5 16.4%
Totals for Area of Interest 21.6 100.0%
Description
Hydrologic soil groups are based on estimates of runoff potential. Soils are
assigned to one of four groups according to the rate of water infiltration when the
soils are not protected by vegetation, are thoroughly wet, and receive
precipitation from long-duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D) and
three dual classes (A/D, B/D, and C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential) when
thoroughly wet. These consist mainly of deep, well drained to excessively
drained sands or gravelly sands. These soils have a high rate of water
transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well
drained soils that have moderately fine texture to moderately coarse texture.
These soils have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of
water transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when
thoroughly wet. These consist chiefly of clays that have a high shrink-swell
potential, soils that have a high water table, soils that have a claypan or clay
layer at or near the surface, and soils that are shallow over nearly impervious
material. These soils have a very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is
for drained areas and the second is for undrained areas. Only the soils that in
their natural condition are in group D are assigned to dual classes.
Hydrologic Soil Group—Moore County, North Carolina Property Line
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
8/16/2017
Page 3 of 4
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Hydrologic Soil Group—Moore County, North Carolina Property Line
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
8/16/2017
Page 4 of 4
ABERDEEN TRANSMISSION HQ
DKE-17280
PRECIPITATION DATA
Element Details
41ID Notes
AberdeenLabel
1 Year
1 YearLabel min5.00Increment
years1Return Event min1,440.00End Time
min0.00Start Time CumulativeStorm Event Depth Type
1 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.010.010.010.000.000.00
0.030.030.020.020.0225.00
0.050.040.040.040.0350.00
0.060.060.050.050.0575.00
0.080.070.070.070.06100.00
0.090.090.090.080.08125.00
0.110.110.100.100.10150.00
0.130.120.120.120.11175.00
0.140.140.130.130.13200.00
0.160.150.150.150.14225.00
0.170.170.170.160.16250.00
0.190.190.180.180.18275.00
0.200.200.200.200.19300.00
0.220.220.210.210.21325.00
0.240.240.230.230.22350.00
0.270.260.260.250.25375.00
0.300.290.290.280.27400.00
0.320.320.310.310.30425.00
0.350.350.340.340.33450.00
0.380.370.370.360.36475.00
0.410.400.400.390.39500.00
0.440.430.420.420.41525.00
0.490.480.470.460.45550.00
0.540.530.520.510.50575.00
0.590.580.570.560.55600.00
0.640.630.620.610.60625.00
0.710.680.660.650.64650.00
0.860.800.770.750.73675.00
1.731.291.071.000.93700.00
2.232.162.092.021.95725.00
2.392.362.342.322.30750.00
2.462.452.442.432.41775.00
2.502.492.482.472.46800.00
2.552.542.532.522.51825.00
2.602.592.582.572.56850.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
1 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
2.652.642.632.622.61875.00
2.682.682.672.672.66900.00
2.712.702.702.692.69925.00
2.742.732.732.722.72950.00
2.772.762.752.752.74975.00
2.792.792.782.782.771,000.00
2.822.822.812.802.801,025.00
2.852.842.842.832.831,050.00
2.872.872.862.862.851,075.00
2.892.882.882.882.871,100.00
2.902.902.902.892.891,125.00
2.922.912.912.912.911,150.00
2.932.932.932.922.921,175.00
2.952.952.942.942.941,200.00
2.972.962.962.962.951,225.00
2.982.982.982.972.971,250.00
3.002.992.992.992.991,275.00
3.013.013.013.003.001,300.00
3.033.033.023.023.021,325.00
3.053.043.043.043.031,350.00
3.063.063.063.053.051,375.00
3.083.073.073.073.061,400.00
(N/A)3.093.093.083.081,425.00
2 Year
2 YearLabel min5.00Increment
years2Return Event min1,440.00End Time
min0.00Start Time CumulativeStorm Event Depth Type
2 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.020.010.010.000.000.00
0.030.030.030.020.0225.00
0.050.050.050.040.0450.00
0.070.070.060.060.0675.00
0.090.090.080.080.08100.00
0.110.110.100.100.09125.00
0.130.120.120.120.11150.00
0.150.140.140.140.13175.00
0.170.160.160.150.15200.00
0.180.180.180.170.17225.00
0.200.200.200.190.19250.00
0.220.220.210.210.21275.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
2 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.240.240.230.230.23300.00
0.260.260.250.250.24325.00
0.280.280.270.270.26350.00
0.320.310.300.300.29375.00
0.350.350.340.330.32400.00
0.390.380.370.370.36425.00
0.420.410.410.400.39450.00
0.450.450.440.430.43475.00
0.490.480.470.470.46500.00
0.530.520.510.500.50525.00
0.590.580.560.550.54550.00
0.650.640.630.610.60575.00
0.710.700.690.670.66600.00
0.770.760.750.740.72625.00
0.850.820.800.790.78650.00
1.040.960.930.900.88675.00
2.081.561.301.211.13700.00
2.692.602.522.432.35725.00
2.882.862.832.802.78750.00
2.972.962.952.942.91775.00
3.023.013.002.992.98800.00
3.083.073.063.043.03825.00
3.143.133.123.113.09850.00
3.203.193.183.173.15875.00
3.243.243.233.223.22900.00
3.283.273.263.263.25925.00
3.313.303.303.293.28950.00
3.343.343.333.323.32975.00
3.383.373.373.363.351,000.00
3.413.413.403.393.391,025.00
3.453.443.433.433.421,050.00
3.473.473.463.463.451,075.00
3.493.493.483.483.481,100.00
3.513.513.503.503.491,125.00
3.533.523.523.523.511,150.00
3.553.543.543.543.531,175.00
3.573.563.563.553.551,200.00
3.583.583.583.573.571,225.00
3.603.603.603.593.591,250.00
3.623.623.613.613.611,275.00
3.643.643.633.633.631,300.00
3.663.663.653.653.641,325.00
3.683.673.673.673.661,350.00
3.703.693.693.693.681,375.00
3.723.713.713.703.701,400.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
2 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
(N/A)3.733.733.723.721,425.00
5 Year
5 YearLabel min5.00Increment
years5Return Event min1,440.00End Time
min0.00Start Time CumulativeStorm Event Depth Type
5 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.020.010.010.010.000.00
0.040.040.030.030.0225.00
0.070.060.060.050.0550.00
0.090.080.080.070.0775.00
0.110.110.100.100.09100.00
0.140.130.130.120.12125.00
0.160.150.150.140.14150.00
0.180.180.170.170.16175.00
0.210.200.200.190.19200.00
0.230.220.220.210.21225.00
0.250.250.240.240.23250.00
0.280.270.270.260.26275.00
0.300.290.290.280.28300.00
0.320.320.310.310.30325.00
0.350.340.340.330.33350.00
0.400.390.380.370.36375.00
0.440.430.420.420.41400.00
0.490.480.470.460.45425.00
0.530.520.510.500.50450.00
0.580.570.560.550.54475.00
0.620.610.600.590.58500.00
0.670.660.650.640.63525.00
0.750.730.720.700.69550.00
0.820.810.790.780.76575.00
0.900.880.870.850.84600.00
0.970.950.940.930.91625.00
1.081.051.011.000.98650.00
1.341.231.191.161.12675.00
2.591.991.671.561.45700.00
3.353.243.133.022.90725.00
3.613.573.533.503.46750.00
3.723.713.693.683.64775.00
3.803.783.773.753.74800.00
3.873.863.843.833.81825.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
5 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
3.953.933.923.903.89850.00
4.024.013.993.983.96875.00
4.074.064.054.044.04900.00
4.124.114.104.094.08925.00
4.164.154.144.134.12950.00
4.204.204.194.184.17975.00
4.254.244.234.224.211,000.00
4.294.284.284.274.261,025.00
4.344.334.324.314.301,050.00
4.374.364.364.364.351,075.00
4.394.394.384.384.371,100.00
4.424.414.414.404.401,125.00
4.444.434.434.434.421,150.00
4.464.464.454.454.441,175.00
4.494.484.484.474.471,200.00
4.514.504.504.504.491,225.00
4.534.534.524.524.511,250.00
4.564.554.554.544.541,275.00
4.584.574.574.564.561,300.00
4.604.604.594.594.581,325.00
4.634.624.624.614.611,350.00
4.654.644.644.634.631,375.00
4.674.674.664.664.651,400.00
(N/A)4.694.694.684.681,425.00
10 Year
10 YearLabel min5.00Increment
years10Return Event min1,440.00End Time
min0.00Start Time CumulativeStorm Event Depth Type
10 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.020.020.010.010.000.00
0.050.040.040.030.0325.00
0.070.070.060.060.0550.00
0.100.100.090.080.0875.00
0.130.120.120.110.11100.00
0.150.150.140.140.13125.00
0.180.170.170.160.16150.00
0.210.200.200.190.19175.00
0.230.230.220.220.21200.00
0.260.250.250.240.24225.00
0.290.280.270.270.26250.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
10 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.310.310.300.300.29275.00
0.340.330.330.320.32300.00
0.360.360.350.350.34325.00
0.400.390.380.380.37350.00
0.450.440.430.420.41375.00
0.510.500.490.480.46400.00
0.560.550.540.530.52425.00
0.610.600.590.580.57450.00
0.670.650.640.630.62475.00
0.720.710.700.690.68500.00
0.780.760.750.740.73525.00
0.870.850.830.810.80550.00
0.960.940.920.900.88575.00
1.041.031.010.990.97600.00
1.141.121.101.081.06625.00
1.281.231.191.171.15650.00
1.581.451.411.361.32675.00
2.992.331.981.851.72700.00
3.873.733.603.473.33725.00
4.174.134.094.044.00750.00
4.324.304.284.264.22775.00
4.414.394.374.354.33800.00
4.494.484.464.444.42825.00
4.584.574.554.534.51850.00
4.674.654.644.624.60875.00
4.734.724.714.704.69900.00
4.794.774.764.754.74925.00
4.844.834.824.814.80950.00
4.894.884.874.864.85975.00
4.944.934.924.914.901,000.00
5.004.994.984.964.951,025.00
5.055.045.035.025.011,050.00
5.095.085.085.075.061,075.00
5.115.115.105.105.091,100.00
5.145.135.135.125.121,125.00
5.175.165.155.155.141,150.00
5.195.195.185.185.171,175.00
5.225.215.215.205.201,200.00
5.245.245.235.235.221,225.00
5.275.275.265.265.251,250.00
5.305.295.295.285.281,275.00
5.325.325.315.315.301,300.00
5.355.345.345.335.331,325.00
5.385.375.375.365.361,350.00
5.405.405.395.395.381,375.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
10 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
5.435.425.425.415.411,400.00
(N/A)5.455.455.445.431,425.00
25 Year
25 YearLabel min5.00Increment
years25Return Event min1,440.00End Time
min0.00Start Time CumulativeStorm Event Depth Type
25 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.020.020.010.010.000.00
0.050.050.040.040.0325.00
0.090.080.070.070.0650.00
0.120.110.100.100.0975.00
0.150.140.130.130.12100.00
0.180.170.160.160.15125.00
0.210.200.190.190.18150.00
0.240.230.220.220.21175.00
0.270.260.250.250.24200.00
0.300.290.280.280.27225.00
0.330.320.310.310.30250.00
0.360.350.340.340.33275.00
0.390.380.380.370.36300.00
0.420.410.410.400.39325.00
0.460.450.440.430.42350.00
0.530.510.500.490.48375.00
0.590.580.570.550.54400.00
0.660.650.630.620.61425.00
0.730.710.700.690.67450.00
0.790.780.770.750.74475.00
0.860.840.830.820.80500.00
0.930.910.900.880.87525.00
1.041.021.000.970.95550.00
1.151.121.101.081.06575.00
1.251.231.211.191.17600.00
1.371.351.321.301.27625.00
1.561.501.451.421.40650.00
1.941.781.721.671.61675.00
3.532.802.422.262.10700.00
4.554.394.234.073.91725.00
4.934.884.824.774.72750.00
5.125.095.075.044.99775.00
5.245.225.205.175.14800.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
25 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
5.355.325.305.285.26825.00
5.455.435.415.395.37850.00
5.565.545.525.495.47875.00
5.635.625.615.595.58900.00
5.705.695.675.665.65925.00
5.775.755.745.735.71950.00
5.835.825.805.795.78975.00
5.905.885.875.865.841,000.00
5.965.955.945.925.911,025.00
6.036.026.005.995.981,050.00
6.076.076.066.066.041,075.00
6.106.106.096.096.081,100.00
6.136.136.126.126.111,125.00
6.166.166.156.156.141,150.00
6.196.196.186.186.171,175.00
6.226.226.216.216.201,200.00
6.256.256.246.246.231,225.00
6.296.286.276.276.261,250.00
6.326.316.306.306.291,275.00
6.356.346.336.336.321,300.00
6.386.376.366.366.351,325.00
6.416.406.396.396.381,350.00
6.446.436.426.426.411,375.00
6.476.466.456.456.441,400.00
(N/A)6.496.486.486.471,425.00
50 Year
50 YearLabel min5.00Increment
years50Return Event min1,440.00End Time
min0.00Start Time CumulativeStorm Event Depth Type
50 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.030.020.010.010.000.00
0.060.050.050.040.0325.00
0.090.080.080.070.0750.00
0.120.120.110.100.1075.00
0.160.150.140.140.13100.00
0.190.180.170.170.16125.00
0.220.210.210.200.19150.00
0.250.250.240.230.23175.00
0.280.280.270.270.26200.00
0.320.310.300.300.29225.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
50 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.350.340.340.330.32250.00
0.380.380.370.360.36275.00
0.410.410.400.390.39300.00
0.450.440.430.430.42325.00
0.500.480.470.460.45350.00
0.570.560.540.530.51375.00
0.650.640.620.600.59400.00
0.730.710.700.680.67425.00
0.800.790.770.760.74450.00
0.880.870.850.840.82475.00
0.960.940.930.910.90500.00
1.051.021.010.990.97525.00
1.171.141.121.091.07550.00
1.291.271.241.221.19575.00
1.421.391.371.341.32600.00
1.561.531.501.471.44625.00
1.781.721.661.621.59650.00
2.212.031.971.911.84675.00
3.963.172.772.582.40700.00
5.104.914.734.544.36725.00
5.535.475.415.345.28750.00
5.755.725.695.665.59775.00
5.895.875.855.815.78800.00
6.025.995.975.945.92825.00
6.146.126.096.076.04850.00
6.276.246.226.196.17875.00
6.356.346.326.316.29900.00
6.436.416.406.386.37925.00
6.516.496.486.466.44950.00
6.586.576.556.546.52975.00
6.666.656.636.616.601,000.00
6.746.726.716.696.681,025.00
6.816.806.786.776.751,050.00
6.866.866.856.856.831,075.00
6.906.896.886.886.871,100.00
6.936.926.926.916.901,125.00
6.966.966.956.946.941,150.00
6.996.996.986.976.971,175.00
7.037.027.017.017.001,200.00
7.067.057.057.047.031,225.00
7.097.087.087.077.071,250.00
7.127.127.117.107.101,275.00
7.167.157.147.147.131,300.00
7.197.187.177.177.161,325.00
7.227.217.217.207.191,350.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
50 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
7.257.257.247.237.231,375.00
7.287.287.277.277.261,400.00
(N/A)7.317.307.307.291,425.00
100 Year
100 YearLabel min5.00Increment
years100Return Event min1,440.00End Time
min0.00Start Time CumulativeStorm Event Depth Type
100 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
0.030.020.010.010.000.00
0.060.050.050.040.0325.00
0.100.090.080.080.0750.00
0.130.120.120.110.1075.00
0.160.160.150.140.14100.00
0.200.190.180.180.17125.00
0.230.230.220.210.20150.00
0.270.260.250.250.24175.00
0.300.290.290.280.27200.00
0.330.330.320.310.31225.00
0.370.360.350.350.34250.00
0.400.400.390.380.37275.00
0.440.430.420.420.41300.00
0.470.460.460.450.44325.00
0.530.510.490.480.48350.00
0.620.600.580.560.54375.00
0.710.690.670.650.63400.00
0.800.780.760.740.72425.00
0.880.870.850.830.81450.00
0.970.960.940.920.90475.00
1.061.051.031.010.99500.00
1.161.141.121.101.08525.00
1.311.281.251.221.19550.00
1.451.421.391.361.33575.00
1.591.561.531.501.48600.00
1.761.721.681.651.62625.00
2.021.951.881.841.80650.00
2.522.312.242.172.10675.00
4.403.563.142.932.72700.00
5.645.445.235.024.82725.00
6.146.075.995.925.85750.00
6.406.366.326.286.21775.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
100 Year
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Depth
(in)
Time
(min)
6.576.546.526.486.44800.00
6.716.696.666.636.60825.00
6.866.836.806.776.74850.00
7.006.976.946.916.88875.00
7.107.087.067.047.03900.00
7.197.177.157.137.12925.00
7.287.267.247.227.20950.00
7.377.357.337.317.29975.00
7.467.447.427.407.381,000.00
7.557.537.517.497.471,025.00
7.637.627.607.587.561,050.00
7.697.687.687.677.651,075.00
7.727.727.717.707.701,100.00
7.767.757.757.747.731,125.00
7.797.797.787.777.771,150.00
7.837.827.817.817.801,175.00
7.867.857.857.847.831,200.00
7.907.897.887.877.871,225.00
7.937.927.927.917.901,250.00
7.967.967.957.947.941,275.00
8.007.997.987.987.971,300.00
8.038.028.028.018.001,325.00
8.078.068.058.048.041,350.00
8.108.098.098.088.071,375.00
8.138.138.128.118.111,400.00
(N/A)8.168.158.158.141,425.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
100 Year 50 Year 25 Year 10 Year 5 Year
2 Year 1 YearDepth(in)8.75
7.50
6.25
5.00
3.75
2.50
1.25
0.00
Time (min)
1,440.001,296.001,152.001,008.00864.00720.00576.00432.00288.00144.000.00
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
ABERDEEN TRANSMISSION HQ
DKE-17280
PRE-DEVELOPMENT HYDROLOGIC
CALCULATIONS
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number: DKE-17280 Calculated By: J. Mattingly, EI
INPUT SUMMARY
Total Area
Subbasin ID Impervious Open Wooded Pond Total Impervious Open Wooded Pond Total [acres]SCS CN Tc [min]
1 0.50 0.07 0.42 0.00 0.99 0.00 0.00 0.00 0.00 0.00 0.99 65 5.00
2A 2.11 1.17 0.93 0.00 4.21 0.00 0.00 0.00 0.00 0.00 4.21 67 5.00
2B 0.25 0.94 3.46 0.00 4.64 0.96 2.40 0.00 0.00 3.37 8.01 49 21.30
3 1.01 1.54 2.21 0.00 4.77 0.00 0.00 0.00 0.00 0.00 4.77 47 27.57
Unanalyzed 0.95 0.59 5.48 0.00 7.02 0.00 0.00 0.00 0.00 0.00 7.02 50 -
Totals 4.82 4.31 12.50 0.00 21.63 0.96 2.40 0.00 0.00 3.37 25.00
PRE DEVELOPMENT HYDROLOGIC SUMMARY
Onsite Area [acres]Offsite Area [acres]
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:1
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =100%
HSG 'B' =0%
HSG 'C' =0%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 39
Wooded 30
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 21,729 0.50
39 3,040 0.07
30 18,297 0.42
100 0 0.00
98 0 0.00
39 0 0.00
30 0 0.00
100 0 0.00
Total Area =43,066 sf
=0.99 acres
Composite SCS CN =65
% Impervious =50.46%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Time of Concentration =5.00 minutes
SCS Lag Time =3.00 minutes
Offsite Pond -
PRE DEVELOPMENT HYDROLOGIC CALCULATIONS
Offsite Impervious -
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Comments
-
Assume good condition
Assume good condition
-
Contributing Area
Onsite Impervious
Onsite Open
Onsite Wooded
Onsite Pond
Comments
-
Assume good condition
Assume good condition
-
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:2A
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =100%
HSG 'B' =0%
HSG 'C' =0%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 39
Wooded 30
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 91,935 2.11
39 51,157 1.17
30 40,491 0.93
100 0 0.00
98 0 0.00
39 0 0.00
30 0 0.00
100 0 0.00
Total Area =183,583 sf
=4.21 acres
Composite SCS CN =67
% Impervious =50.08%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Time of Concentration =5.00 minutes
SCS Lag Time =3.00 minutes
-
PRE DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:2B
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =83%
HSG 'B' =0%
HSG 'C' =17%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 45
Wooded 37
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 10,754 0.25
45 40,822 0.94
37 150,746 3.46
100 0 0.00
98 41,906 0.96
45 104,744 2.40
37 0 0.00
100 0 0.00
Total Area =348,972 sf
=8.01 acres
Composite SCS CN =49
% Impervious =15.09%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Segment 1: Overland Flow Segment 2: Concentrated Flow
Length =100 ft Length =344 ft
Upstream Elevation =452.00 ft Upstream Elevation =451.00 ft
Downstream Elevation =451.00 ft Downstream Elevation =440.05 ft
Height =1.00 ft Height =10.95 ft
Slope =0.0100 ft/ft Slope =0.0318 ft/ft
Manning's n =0.24 grassed Paved?No
P (2-year/24-hour) =3.73 inches (Aberdeen, NC)Velocity =2.88 ft/sec
Segment Time =17.44 minutes Segment Time =1.99 minutes
Segment 3: Pipe Flow Segment 4: Channel Flow
Length =44 ft Length =436 ft
Upstream Elevation =440.05 ft Upstream Elevation =439.85 ft
Downstream Elevation =439.85 ft Downstream Elevation =435.00 ft
Height =0.20 ft Height =4.85 ft
Slope =0.0045 ft/ft Slope =0.0111 ft/ft
Manning's n =0.013 RCP Manning's n =0.045 natural channel
Flow Area =3.14 lf (assume 24")Flow Area =16.00 lf (assume 4x4 channel)
Wetted Perimeter =6.28 sf (assume 24")Wetted Perimeter =12.00 sf (assume 4x4 channel)
Channel Velocity =4.87 ft/sec Channel Velocity =4.23 ft/sec
Segment Time =0.15 minutes Segment Time =1.72 minutes
Time of Concentration =21.30 minutes
SCS Lag Time =12.78 minutes
-
PRE DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:3
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =100%
HSG 'B' =0%
HSG 'C' =0%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 39
Wooded 30
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 44,177 1.01
39 67,093 1.54
30 96,320 2.21
100 0 0.00
98 0 0.00
39 0 0.00
30 0 0.00
100 0 0.00
Total Area =207,590 sf
=4.77 acres
Composite SCS CN =47
% Impervious =21.28%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Segment 1: Overland Flow Segment 2: Concentrated Flow
Length =100 ft Length =529 ft
Upstream Elevation =440.00 ft Upstream Elevation =438.50 ft
Downstream Elevation =438.50 ft Downstream Elevation =429.00 ft
Height =1.50 ft Height =9.50 ft
Slope =0.0150 ft/ft Slope =0.0180 ft/ft
Manning's n =0.40 wooded Paved?No
P (2-year/24-hour) =3.73 inches (Aberdeen, NC)Velocity =2.16 ft/sec
Segment Time =22.32 minutes Segment Time =4.08 minutes
Segment 3: Channel Flow
Length =240 ft
Upstream Elevation =429.00 ft
Downstream Elevation =428.00 ft
Height =1.00 ft
Slope =0.0042 ft/ft
Manning's n =0.045 natural channel
Flow Area =36.00 lf (assume 6x6 channel)
Wetted Perimeter =18.00 sf (assume 6x6 channel)
Channel Velocity =3.39 ft/sec
Segment Time =1.18 minutes
Time of Concentration =27.57 minutes
SCS Lag Time =16.54 minutes
-
PRE DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:Unanalyzed
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =70%
HSG 'B' =0%
HSG 'C' =30%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 50
Wooded 42
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 41,365 0.95
50 25,646 0.59
42 238,628 5.48
100 0 0.00
98 0 0.00
50 0 0.00
42 0 0.00
100 0 0.00
Total Area =305,639 sf
=7.02 acres
Composite SCS CN =50
% Impervious =13.53%
-
PRE DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:Reach
Reach
(REF: SCS Segmental Approach, TR-55).
Reach: 2B to POA 2
Length =363 ft Length =39 ft
Upstream Elevation =435.00 ft Upstream Elevation =426.98 ft
Downstream Elevation =426.98 ft Downstream Elevation =426.70 ft
Height =8.02 ft Height =0.28 ft
Slope =0.0221 ft/ft Slope =0.0072 ft/ft
Manning's n =0.045 natural channel Manning's n =0.013 RCP
Flow Area =9.00 lf (assume 3x3 channel)Flow Area =3.14 lf (assume 24")
Wetted Perimeter =9.00 sf (assume 3x3 channel) Wetted Perimeter =6.28 sf (assume 24")
Channel Velocity =4.92 ft/sec Channel Velocity =6.12 ft/sec
Segment Time =1.23 minutes Segment Time =0.11 minutes
Length =125 ft Length =39 ft
Upstream Elevation =426.70 ft Upstream Elevation =425.05 ft
Downstream Elevation =425.05 ft Downstream Elevation =425.04 ft
Height =1.65 ft Height =0.01 ft
Slope =0.0132 ft/ft Slope =0.0003 ft/ft
Manning's n =0.045 natural channel Manning's n =0.013 RCP
Flow Area =16.00 lf (assume 4x4 channel)Flow Area =3.14 lf (assume 24")
Wetted Perimeter =12.00 sf (assume 4x4 channel) Wetted Perimeter =6.28 sf (assume 24")
Channel Velocity =4.61 ft/sec Channel Velocity =1.16 ft/sec
Segment Time =0.45 minutes Segment Time =0.56 minutes
Length =149 ft
Upstream Elevation =425.04 ft
Downstream Elevation =424.00 ft
Height =1.04 ft
Slope =0.0070 ft/ft
Manning's n =0.045 natural channel
Flow Area =36.00 lf (assume 6x6 channel)
Wetted Perimeter =18.00 sf (assume 6x6 channel)
Channel Velocity =4.39 ft/sec
Segment Time =0.57 minutes
Time of Concentration =2.92 minutes
SCS Lag Time =1.75 minutes
PRE DEVELOPMENT HYDROLOGIC CALCULATIONS
3
2B
2A
1 POA 2B
POA 3POA 2POA 1
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Subsection: Master Network Summary
Catchments Summary
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ft³)
Return
Event
(years)
ScenarioLabel
0.72722.001,965.0001Pre 1 Year1
1.32722.003,141.0002Pre 2 Year1
2.89722.007,033.00010Pre 10 Year1
3.81721.009,739.00025Pre 25 Year1
3.86722.009,613.0001Pre 1 Year2A
6.55722.0014,985.0002Pre 2 Year2A
13.48722.0032,400.00010Pre 10 Year2A
17.50721.0044,345.00025Pre 25 Year2A
0.12764.002,537.0001Pre 1 Year2B
0.70756.006,460.0002Pre 2 Year2B
3.75736.0023,723.00010Pre 10 Year2B
6.75735.0037,839.00025Pre 25 Year2B
0.04904.00964.0001Pre 1 Year3
0.23761.002,892.0002Pre 2 Year3
1.59754.0012,055.00010Pre 10 Year3
2.92743.0019,804.00025Pre 25 Year3
Node Summary
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ft³)
Return
Event
(years)
ScenarioLabel
0.72722.001,965.0001Pre 1 YearPOA 1
1.32722.003,141.0002Pre 2 YearPOA 1
2.89722.007,033.00010Pre 10 YearPOA 1
3.81721.009,739.00025Pre 25 YearPOA 1
3.86722.0012,140.0001Pre 1 YearPOA 2
6.55722.0021,428.0002Pre 2 YearPOA 2
13.73722.0056,084.00010Pre 10 YearPOA 2
18.53722.0082,132.00025Pre 25 YearPOA 2
0.04904.00964.0001Pre 1 YearPOA 3
0.23761.002,892.0002Pre 2 YearPOA 3
1.59754.0012,055.00010Pre 10 YearPOA 3
2.92743.0019,804.00025Pre 25 YearPOA 3
0.12764.002,537.0001Pre 1 YearPOA 2B
0.70756.006,460.0002Pre 2 YearPOA 2B
3.75736.0023,723.00010Pre 10 YearPOA 2B
6.75735.0037,839.00025Pre 25 YearPOA 2B
4/19/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
ABERDEEN TRANSMISSION HQ
DKE-17280
POST-DEVELOPMENT HYDROLOGIC
CALCULATIONS
Project Name: Aberdeen Transmission HQ Date:3/19/2018
Project Number: DKE-17280 Calculated By: J. Mattingly, EI
INPUT SUMMARY
Total Area
Subbasin ID Impervious Open Wooded Pond Total Impervious Open Wooded Pond Total [acres]SCS CN Tc [min]
1 0.24 0.23 0.02 0.00 0.49 0.00 0.00 0.00 0.00 0.00 0.49 68 5.00
2A To SWMF 7.11 1.56 1.10 0.00 9.76 0.00 0.00 0.00 0.00 0.00 9.76 81 5.00
2A Bypass 0.13 0.26 0.00 0.00 0.39 0.00 0.00 0.00 0.00 0.00 0.39 59 5.00
2B 0.25 0.94 3.46 0.00 4.64 0.96 2.40 0.00 0.00 3.37 8.01 49 21.30
3 0.19 0.31 0.06 0.00 0.56 0.00 0.00 0.00 0.00 0.00 0.56 58 15.92
Unanalyzed 1.91 0.16 3.71 0.00 5.77 0.00 0.00 0.00 0.00 0.00 5.77 65 -
Totals 9.83 3.45 8.34 0.00 21.63 0.96 2.40 0.00 0.00 3.37 24.99
POST DEVELOPMENT HYDROLOGIC SUMMARY
Onsite Area [acres]Offsite Area [acres]
Project Name: Aberdeen Transmission HQ Date:3/19/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:1
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =100%
HSG 'B' =0%
HSG 'C' =0%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 39
Wooded 30
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 10,406 0.24
39 10,133 0.23
30 694 0.02
100 0 0.00
98 0 0.00
39 0 0.00
30 0 0.00
100 0 0.00
Total Area =21,233 sf
=0.49 acres
Composite SCS CN =68
% Impervious =49.01%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Time of Concentration =5.00 minutes
SCS Lag Time =3.00 minutes
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
-
POST DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Project Name: Aberdeen Transmission HQ Date:3/19/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:2A To SWMF
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =98%
HSG 'B' =0%
HSG 'C' =2%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 40
Wooded 31
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 309,724 7.11
40 67,800 1.56
31 47,834 1.10
100 0 0.00
98 0 0.00
40 0 0.00
31 0 0.00
100 0 0.00
Total Area =425,358 sf
=9.76 acres
Composite SCS CN =81
% Impervious =72.81%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Time of Concentration =5.00 minutes
SCS Lag Time =3.00 minutes
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
-
POST DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Project Name: Aberdeen Transmission HQ Date:3/19/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:2A Bypass
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =98%
HSG 'B' =0%
HSG 'C' =2%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 40
Wooded 31
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 5,773 0.13
40 11,301 0.26
31 0 0.00
100 0 0.00
98 0 0.00
40 0 0.00
31 0 0.00
100 0 0.00
Total Area =17,074 sf
=0.39 acres
Composite SCS CN =59
% Impervious =33.81%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Time of Concentration =5.00 minutes
SCS Lag Time =3.00 minutes
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
-
POST DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Project Name: Aberdeen Transmission HQ Date:3/19/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:2B
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =83%
HSG 'B' =0%
HSG 'C' =17%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 45
Wooded 37
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 10,754 0.25
45 40,822 0.94
37 150,746 3.46
100 0 0.00
98 41,906 0.96
45 104,744 2.40
37 0 0.00
100 0 0.00
Total Area =348,972 sf
=8.01 acres
Composite SCS CN =49
% Impervious =15.09%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Segment 1: Overland Flow Segment 2: Concentrated Flow
Length =100 ft Length =344 ft
Upstream Elevation =452.00 ft Upstream Elevation =451.00 ft
Downstream Elevation =451.00 ft Downstream Elevation =440.05 ft
Height =1.00 ft Height =10.95 ft
Slope =0.0100 ft/ft Slope =0.0318 ft/ft
Manning's n =0.24 grassed Paved?No
P (2-year/24-hour) =3.73 inches (Aberdeen, NC)Velocity =2.88 ft/sec
Segment Time =17.44 minutes Segment Time =1.99 minutes
Segment 3: Pipe Flow Segment 4: Channel Flow
Length =44 ft Length =436 ft
Upstream Elevation =440.05 ft Upstream Elevation =439.85 ft
Downstream Elevation =439.85 ft Downstream Elevation =435.00 ft
Height =0.20 ft Height =4.85 ft
Slope =0.0045 ft/ft Slope =0.0111 ft/ft
Manning's n =0.013 RCP Manning's n =0.045 natural channel
Flow Area =3.14 lf (assume 24")Flow Area =16.00 lf (assume 4x4 channel)
Wetted Perimeter =6.28 sf (assume 24")Wetted Perimeter =12.00 sf (assume 4x4 channel)
Channel Velocity =4.87 ft/sec Channel Velocity =4.23 ft/sec
Segment Time =0.15 minutes Segment Time =1.72 minutes
Time of Concentration =21.30 minutes
SCS Lag Time =12.78 minutes
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
-
POST DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Project Name: Aberdeen Transmission HQ Date:3/19/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:3
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =100%
HSG 'B' =0%
HSG 'C' =0%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 39
Wooded 30
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 8,383 0.19
39 13,474 0.31
30 2,707 0.06
100 0 0.00
98 0 0.00
39 0 0.00
30 0 0.00
100 0 0.00
Total Area =24,564 sf
=0.56 acres
Composite SCS CN =58
% Impervious =34.13%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55).
Segment 1: Overland Flow Segment 2: Concentrated Flow
Length =100 ft Length =190 ft
Upstream Elevation =431.00 ft Upstream Elevation =429.00 ft
Downstream Elevation =429.00 ft Downstream Elevation =428.00 ft
Height =2.00 ft Height =1.00 ft
Slope =0.0200 ft/ft Slope =0.0053 ft/ft
Manning's n =0.24 grassed Paved?No
P (2-year/24-hour) =3.73 inches (Aberdeen, NC)Velocity =1.17 ft/sec
Segment Time =13.22 minutes Segment Time =2.71 minutes
Time of Concentration =15.92 minutes
SCS Lag Time =9.55 minutes
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Offsite Pond -
Onsite Wooded Assume good condition
Onsite Pond -
Offsite Impervious -
Contributing Area Comments
Onsite Impervious -
Onsite Open Assume good condition
-
POST DEVELOPMENT HYDROLOGIC CALCULATIONS
Comments
-
Assume good condition
Assume good condition
Project Name: Aberdeen Transmission HQ Date:3/19/2018
Project Number:DKE-17280 Calculated By: J. Mattingly, EI
Subbasin ID:Unanalyzed
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
A 98 39 30 100
B 98 61 55 100
C 98 74 70 100
D 98 80 77 100
HSG 'A' =53%
HSG 'B' =0%
HSG 'C' =47%
HSG 'D' =0%
Cover Composite
Condition SCS CN
Impervious 98
Open 55
Wooded 49
Pond 100
WATERSHED BREAKDOWN
Composite Area Area
SCS CN [sf][acres]
98 83,194 1.91
55 6,871 0.16
49 161,431 3.71
100 0 0.00
98 0 0.00
55 0 0.00
49 0 0.00
100 0 0.00
Total Area =251,496 sf
=5.77 acres
Composite SCS CN =65
% Impervious =33.08%
Onsite Open
Onsite Wooded
Onsite Pond
Comments
-
Assume good condition
Assume good condition
-
Offsite Pond -
POST DEVELOPMENT HYDROLOGIC CALCULATIONS
Offsite Impervious -
Offsite Open Assume good condition
Offsite Wooded Assume good condition
Comments
-
Assume good condition
Assume good condition
-
Contributing Area
Onsite Impervious
3/13/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Subsection: Master Network Summary
Catchments Summary
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ft³)
Return
Event
(years)
ScenarioLabel
0.50722.001,196.0001Post 1 Year1
0.82722.001,843.0002Post 2 Year1
1.64722.003,919.00010Post 10 Year1
2.11721.005,334.00025Post 25 Year1
0.12764.002,537.0001Post 1 Year2B
0.70756.006,460.0002Post 2 Year2B
3.75736.0023,723.00010Post 10 Year2B
6.75735.0037,839.00025Post 25 Year2B
0.09734.00611.0001Post 1 Year3
0.23732.001,103.0002Post 2 Year3
0.72730.002,880.00010Post 10 Year3
1.03730.004,187.00025Post 25 Year3
24.12721.0048,935.0001Post 1 Year2A To SWMF
32.86721.0067,105.0002Post 2 Year2A To SWMF
51.78721.00119,841.00010Post 10 Year2A To SWMF
61.40721.00153,353.00025Post 25 Year2A To SWMF
0.12726.00472.0001Post 1 Year2A Bypass
0.27723.00833.0002Post 2 Year2A Bypass
0.82722.002,116.00010Post 10 Year2A Bypass
1.15722.003,052.00025Post 25 Year2A Bypass
Node Summary
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ft³)
Return
Event
(years)
ScenarioLabel
0.50722.001,196.0001Post 1 YearPOA 1
0.82722.001,843.0002Post 2 YearPOA 1
1.64722.003,919.00010Post 10 YearPOA 1
2.11721.005,334.00025Post 25 YearPOA 1
0.09734.00611.0001Post 1 YearPOA 3
0.23732.001,103.0002Post 2 YearPOA 3
0.72730.002,880.00010Post 10 YearPOA 3
1.03730.004,187.00025Post 25 YearPOA 3
2.86753.0043,197.0001Post 1 YearPOA 2
3.76752.0065,067.0002Post 2 YearPOA 2
5.56752.00134,679.00010Post 10 YearPOA 2
13.72755.00182,270.00025Post 25 YearPOA 2
Pond Summary
Maximum
Pond Storage
(ft³)
Maximum
Water
Surface
Elevation
(ft)
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ft³)
Return
Event
(years)
ScenarioLabel
4/19/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Subsection: Master Network Summary
Pond Summary
Maximum
Pond Storage
(ft³)
Maximum
Water
Surface
Elevation
(ft)
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ft³)
Return
Event
(years)
ScenarioLabel
(N/A)(N/A)24.12721.0051,471.0001Post 1 YearSWMF (IN)
23,310.000425.072.82755.0042,725.0001Post 1 YearSWMF (OUT)
(N/A)(N/A)32.86721.0073,565.0002Post 2 YearSWMF (IN)
34,063.000425.883.68757.0064,234.0002Post 2 YearSWMF (OUT)
(N/A)(N/A)52.30721.00143,564.00010Post 10 YearSWMF (IN)
70,025.000428.195.42782.00132,563.00010Post 10 YearSWMF (OUT)
(N/A)(N/A)63.22721.00191,193.00025Post 25 YearSWMF (IN)
87,374.000429.1513.51755.00179,218.00025Post 25 YearSWMF (OUT)
4/19/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
ABERDEEN TRANSMISSION HQ
DKE-17280
STORMWATER MANAGEMENT FACILITY
DESIGN CALCULATIONS
Project Name: Aberdeen Transmission HQ Date:3/13/2018
Project Number: DKE-17280 Calculated By: J. Mattingly, EI
Facility ID:SWMF
SWMF
Average Incremental Accumulated Calculated
Contour Stage Contour Area Contour Area Contour Vol Contour Vol Stage
[ft][ft][sf][sf][cf][cf][ft]
422.25 0.00 0
423.00 0.75 6,507 3,254 2,440 2,440 0.70
424.00 1.75 11,336 8,922 8,922 11,362 1.85
425.00 2.75 12,667 12,002 12,002 23,363 2.91
426.00 3.75 14,054 13,361 13,361 36,724 3.86
427.00 4.75 15,498 14,776 14,776 51,500 4.78
428.00 5.75 16,999 16,249 16,249 67,748 5.67
429.00 6.75 18,556 17,778 17,778 85,526 6.57
430.00 7.75 20,169 19,363 19,363 104,888 7.47
b =1.5910
Ks =4281
STAGE-STORAGE FUNCTION
y = 4280.8x1.591
R² = 0.9969
0
20,000
40,000
60,000
80,000
100,000
120,000
0.00 2.00 4.00 6.00 8.00 10.00Storage(CF)Stage (feet)
Storage vs. Stage
Project Name:Aberdeen Transmission HQ Date:3/13/2018
Project Number:DKE-17280 Calculated By:J. Mattingly, EI
Facility ID:SWMF
DESIGN OF RIPRAP OUTLET PROTECTION
Calculations based on NY DOT method - Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual.
Flow, Q10-yr =5.42 cfs
Slope =0.50 %
Pipe Diameter, Do =15 in
=1.25 feet
Number of pipes =1
Pipe separation =0.00 feet
Manning's n =0.013
Zone from graph above =2
Outlet pipe diameter =15 in Length =7.50 ft
Outlet flowrate =5.42 cfs Width =3.75 ft
Outlet velocity =2.27 ft/sec Stone diameter =6.00 in
Material =Class B Thickness =22.00 in
Zone Material Diameter Thickness Length Width
1 Class A 3 9 4 x Do 3 x Do
2 Class B 6 22 6 x Do 3 x Do
3 Class I 13 22 8 x Do 3 x Do
4 Class I 13 22 8 x Do 3 x Do
5 Class II 23 27 10 x Do 3 x Do
6 Class II 23 27 10 x Do 3 x Do
7 Study Required
RIPRAP OUTLET PROTECTION
2.27 ft/sec
0
5
10
15
20
25
0 1 2 3 4 5 6 7 8 9 10Velocity(ft/sec)Pipe diameter (ft)
Figure 8.06.b.1
Zone 1
Zone 2
Zone 3
Zone 4
Zone 5
Zone 6 Zone 7
Storm Event: 1 YearLabel: SWMF
Return Event: 1 yearsSubsection: Elevation-Area Volume Curve
Volume (Total)
(ft³)
Volume
(ft³)
A1+A2+sqr
(A1*A2)
(acres)
Area
(acres)
Planimeter
(ft²)
Elevation
(ft)
0.0000.0000.000.000.00422.25
1,627.0001,627.0000.150.150.00423.00
10,437.0008,811.0000.610.260.00424.00
22,433.00011,995.0000.830.290.00425.00
35,787.00013,354.0000.920.320.00426.00
50,557.00014,770.0001.020.360.00427.00
66,800.00016,243.0001.120.390.00428.00
84,572.00017,772.0001.220.430.00429.00
103,929.00019,357.0001.330.460.00430.00
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: Outlet Structure
Return Event: 1 yearsSubsection: Outlet Input Data
Requested Pond Water Surface Elevations
ft422.25Minimum (Headwater)
ft0.10Increment (Headwater)
ft430.00Maximum (Headwater)
Outlet Connectivity
E2
(ft)
E1
(ft)
OutfallDirectionOutlet IDStructure Type
430.00423.50CulvertForwardOrificeOrifice-Circular
430.00422.25TWForwardCulvertCulvert-Circular
430.00428.75TWForwardWeirRectangular Weir
(N/A)(N/A)TailwaterTailwater Settings
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: Outlet Structure
Return Event: 1 yearsSubsection: Outlet Input Data
Structure ID: Culvert
Structure Type: Culvert-Circular
1Number of Barrels
in15.0Diameter
ft50.00Length
ft50.00Length (Computed Barrel)
ft/ft0.005Slope (Computed)
Outlet Control Data
0.013Manning's n
1Ke
0Kb
0Kr
ft0.00Convergence Tolerance
Inlet Control Data
Form 1Equation Form
0.0098K
2.0000M
0.0398C
0.6700Y
1T1 ratio (HW/D)
1T2 ratio (HW/D)
-1Slope Correction Factor
Use unsubmerged inlet control 0 equation below T1 elevation.
Use submerged inlet control 0 equation above T2 elevation
In transition zone between unsubmerged and submerged inlet
control,
interpolate between flows at T1 & T2...
ft423.70T1 Elevation ft³/s4.80T1 Flow
ft423.88T2 Elevation ft³/s5.49T2 Flow
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: Outlet Structure
Return Event: 1 yearsSubsection: Outlet Input Data
Structure ID: Weir
Structure Type: Rectangular Weir
1Number of Openings
ft428.75Elevation
ft10.00Weir Length
(ft^0.5)/s3.00Weir Coefficient
Structure ID: Orifice
Structure Type: Orifice-Circular
1Number of Openings
ft423.50Elevation
in10.0Orifice Diameter
1Orifice Coefficient
Structure ID: TW
Structure Type: TW Setup, DS Channel
Free OutfallTailwater Type
Convergence Tolerances
30Maximum Iterations
ft0.01Tailwater Tolerance
(Minimum)
ft0.50Tailwater Tolerance
(Maximum)
ft0.01Headwater Tolerance
(Minimum)
ft0.50Headwater Tolerance
(Maximum)
ft³/s0.001Flow Tolerance (Minimum)
ft³/s10.000Flow Tolerance (Maximum)
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: Outlet Structure
Return Event: 1 yearsSubsection: Composite Rating Curve
Composite Outflow Summary
Contributing StructuresConvergence Error
(ft)
Tailwater Elevation
(ft)
Flow
(ft³/s)
Water Surface
Elevation
(ft)
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.25
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.35
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.45
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.55
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.65
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.75
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.85
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00422.95
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00423.05
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00423.15
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00423.25
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00423.35
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00423.45
(no Q:
Orifice,Culvert,Weir)
0.00(N/A)0.00423.50
Orifice,Culvert (no Q:
Weir)
0.00(N/A)0.00423.55
Orifice,Culvert (no Q:
Weir)
0.00(N/A)0.07423.65
Orifice,Culvert (no Q:
Weir)
0.00(N/A)0.18423.75
Orifice,Culvert (no Q:
Weir)
0.00(N/A)0.36423.85
Orifice,Culvert (no Q:
Weir)
0.00(N/A)0.56423.95
Orifice,Culvert (no Q:
Weir)
0.00(N/A)0.80424.05
Orifice,Culvert (no Q:
Weir)
0.00(N/A)1.08424.15
Orifice,Culvert (no Q:
Weir)
0.00(N/A)1.38424.25
Orifice,Culvert (no Q:
Weir)
0.00(N/A)1.73424.35
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: Outlet Structure
Return Event: 1 yearsSubsection: Composite Rating Curve
Composite Outflow Summary
Contributing StructuresConvergence Error
(ft)
Tailwater Elevation
(ft)
Flow
(ft³/s)
Water Surface
Elevation
(ft)
Orifice,Culvert (no Q:
Weir)
0.00(N/A)1.92424.45
Orifice,Culvert (no Q:
Weir)
0.00(N/A)2.09424.55
Orifice,Culvert (no Q:
Weir)
0.00(N/A)2.25424.65
Orifice,Culvert (no Q:
Weir)
0.00(N/A)2.40424.75
Orifice,Culvert (no Q:
Weir)
0.00(N/A)2.54424.85
Orifice,Culvert (no Q:
Weir)
0.00(N/A)2.67424.95
Orifice,Culvert (no Q:
Weir)
0.00(N/A)2.79425.05
Orifice,Culvert (no Q:
Weir)
0.00(N/A)2.92425.15
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.03425.25
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.14425.35
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.25425.45
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.36425.55
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.46425.65
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.55425.75
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.65425.85
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.75425.95
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.83426.05
Orifice,Culvert (no Q:
Weir)
0.00(N/A)3.92426.15
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.01426.25
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.09426.35
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.18426.45
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.26426.55
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.34426.65
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: Outlet Structure
Return Event: 1 yearsSubsection: Composite Rating Curve
Composite Outflow Summary
Contributing StructuresConvergence Error
(ft)
Tailwater Elevation
(ft)
Flow
(ft³/s)
Water Surface
Elevation
(ft)
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.42426.75
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.50426.85
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.57426.95
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.65427.05
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.72427.15
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.79427.25
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.86427.35
Orifice,Culvert (no Q:
Weir)
0.00(N/A)4.94427.45
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.00427.55
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.07427.65
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.14427.75
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.20427.85
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.27427.95
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.34428.05
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.40428.15
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.46428.25
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.52428.35
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.59428.45
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.63428.55
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.68428.65
Orifice,Culvert (no Q:
Weir)
0.00(N/A)5.73428.75
Orifice,Culvert,Weir0.00(N/A)6.73428.85
Orifice,Culvert,Weir0.00(N/A)8.51428.95
Orifice,Culvert,Weir0.00(N/A)10.81429.05
Orifice,Culvert,Weir0.00(N/A)13.51429.15
Orifice,Culvert,Weir0.00(N/A)16.58429.25
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: Outlet Structure
Return Event: 1 yearsSubsection: Composite Rating Curve
Composite Outflow Summary
Contributing StructuresConvergence Error
(ft)
Tailwater Elevation
(ft)
Flow
(ft³/s)
Water Surface
Elevation
(ft)
Orifice,Culvert,Weir0.00(N/A)19.96429.35
Orifice,Culvert,Weir0.00(N/A)23.63429.45
Orifice,Culvert,Weir0.00(N/A)27.58429.55
Orifice,Culvert,Weir0.00(N/A)31.77429.65
Orifice,Culvert,Weir0.00(N/A)36.20429.75
Orifice,Culvert,Weir0.00(N/A)40.85429.85
Orifice,Culvert,Weir0.00(N/A)45.72429.95
Orifice,Culvert,Weir0.00(N/A)48.24430.00
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 1 YearLabel: SWMF (IN)
Return Event: 1 yearsSubsection: Level Pool Pond Routing Summary
Infiltration
No InfiltrationInfiltration Method
(Computed)
Initial Conditions
ft422.25Elevation (Water Surface,
Initial)
ft³0.000Volume (Initial)
ft³/s0.00Flow (Initial Outlet)
ft³/s0.00Flow (Initial Infiltration)
ft³/s0.00Flow (Initial, Total)
min1.00Time Increment
Inflow/Outflow Hydrograph Summary
ft³/s24.12Flow (Peak In)min721.00Time to Peak (Flow, In)
ft³/s2.82Flow (Peak Outlet)min755.00Time to Peak (Flow, Outlet)
ft425.07Elevation (Water Surface,
Peak)
ft³23,309.870Volume (Peak)
Mass Balance (ft³)
ft³0.000Volume (Initial)
ft³51,471.000Volume (Total Inflow)
ft³0.000Volume (Total Infiltration)
ft³42,725.000Volume (Total Outlet
Outflow)
ft³8,724.000Volume (Retained)
ft³-22.000Volume (Unrouted)
%0.0Error (Mass Balance)
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 2 YearLabel: SWMF (IN)
Return Event: 2 yearsSubsection: Level Pool Pond Routing Summary
Infiltration
No InfiltrationInfiltration Method
(Computed)
Initial Conditions
ft422.25Elevation (Water Surface,
Initial)
ft³0.000Volume (Initial)
ft³/s0.00Flow (Initial Outlet)
ft³/s0.00Flow (Initial Infiltration)
ft³/s0.00Flow (Initial, Total)
min1.00Time Increment
Inflow/Outflow Hydrograph Summary
ft³/s32.86Flow (Peak In)min721.00Time to Peak (Flow, In)
ft³/s3.68Flow (Peak Outlet)min757.00Time to Peak (Flow, Outlet)
ft425.88Elevation (Water Surface,
Peak)
ft³34,062.782Volume (Peak)
Mass Balance (ft³)
ft³0.000Volume (Initial)
ft³73,565.000Volume (Total Inflow)
ft³0.000Volume (Total Infiltration)
ft³64,234.000Volume (Total Outlet
Outflow)
ft³9,297.000Volume (Retained)
ft³-34.000Volume (Unrouted)
%0.0Error (Mass Balance)
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 10 YearLabel: SWMF (IN)
Return Event: 10 yearsSubsection: Level Pool Pond Routing Summary
Infiltration
No InfiltrationInfiltration Method
(Computed)
Initial Conditions
ft422.25Elevation (Water Surface,
Initial)
ft³0.000Volume (Initial)
ft³/s0.00Flow (Initial Outlet)
ft³/s0.00Flow (Initial Infiltration)
ft³/s0.00Flow (Initial, Total)
min1.00Time Increment
Inflow/Outflow Hydrograph Summary
ft³/s52.30Flow (Peak In)min721.00Time to Peak (Flow, In)
ft³/s5.42Flow (Peak Outlet)min782.00Time to Peak (Flow, Outlet)
ft428.19Elevation (Water Surface,
Peak)
ft³70,025.468Volume (Peak)
Mass Balance (ft³)
ft³0.000Volume (Initial)
ft³143,564.000Volume (Total Inflow)
ft³0.000Volume (Total Infiltration)
ft³132,563.000Volume (Total Outlet
Outflow)
ft³10,953.000Volume (Retained)
ft³-48.000Volume (Unrouted)
%0.0Error (Mass Balance)
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 25 YearLabel: SWMF (IN)
Return Event: 25 yearsSubsection: Level Pool Pond Routing Summary
Infiltration
No InfiltrationInfiltration Method
(Computed)
Initial Conditions
ft422.25Elevation (Water Surface,
Initial)
ft³0.000Volume (Initial)
ft³/s0.00Flow (Initial Outlet)
ft³/s0.00Flow (Initial Infiltration)
ft³/s0.00Flow (Initial, Total)
min1.00Time Increment
Inflow/Outflow Hydrograph Summary
ft³/s63.22Flow (Peak In)min721.00Time to Peak (Flow, In)
ft³/s13.51Flow (Peak Outlet)min755.00Time to Peak (Flow, Outlet)
ft429.15Elevation (Water Surface,
Peak)
ft³87,374.287Volume (Peak)
Mass Balance (ft³)
ft³0.000Volume (Initial)
ft³191,193.000Volume (Total Inflow)
ft³0.000Volume (Total Infiltration)
ft³179,218.000Volume (Total Outlet
Outflow)
ft³11,911.000Volume (Retained)
ft³-63.000Volume (Unrouted)
%0.0Error (Mass Balance)
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 50 YearLabel: SWMF (IN)
Return Event: 50 yearsSubsection: Level Pool Pond Routing Summary
Infiltration
No InfiltrationInfiltration Method
(Computed)
Initial Conditions
ft422.25Elevation (Water Surface,
Initial)
ft³0.000Volume (Initial)
ft³/s0.00Flow (Initial Outlet)
ft³/s0.00Flow (Initial Infiltration)
ft³/s0.00Flow (Initial, Total)
min1.00Time Increment
Inflow/Outflow Hydrograph Summary
ft³/s71.44Flow (Peak In)min721.00Time to Peak (Flow, In)
ft³/s23.93Flow (Peak Outlet)min752.00Time to Peak (Flow, Outlet)
ft429.46Elevation (Water Surface,
Peak)
ft³93,226.138Volume (Peak)
Mass Balance (ft³)
ft³0.000Volume (Initial)
ft³230,801.000Volume (Total Inflow)
ft³0.000Volume (Total Infiltration)
ft³218,101.000Volume (Total Outlet
Outflow)
ft³12,625.000Volume (Retained)
ft³-74.000Volume (Unrouted)
%0.0Error (Mass Balance)
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
Storm Event: 100 YearLabel: SWMF (IN)
Return Event: 100 yearsSubsection: Level Pool Pond Routing Summary
Infiltration
No InfiltrationInfiltration Method
(Computed)
Initial Conditions
ft422.25Elevation (Water Surface,
Initial)
ft³0.000Volume (Initial)
ft³/s0.00Flow (Initial Outlet)
ft³/s0.00Flow (Initial Infiltration)
ft³/s0.00Flow (Initial, Total)
min1.00Time Increment
Inflow/Outflow Hydrograph Summary
ft³/s79.49Flow (Peak In)min721.00Time to Peak (Flow, In)
ft³/s30.82Flow (Peak Outlet)min751.00Time to Peak (Flow, Outlet)
ft429.63Elevation (Water Surface,
Peak)
ft³96,528.256Volume (Peak)
Mass Balance (ft³)
ft³0.000Volume (Initial)
ft³273,373.000Volume (Total Inflow)
ft³0.000Volume (Total Infiltration)
ft³259,740.000Volume (Total Outlet
Outflow)
ft³13,544.000Volume (Retained)
ft³-89.000Volume (Unrouted)
%0.0Error (Mass Balance)
3/14/2018DKE17280.ppc
J. MattinglyABERDEEN TRANSMISSION HQ
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