Waxhaw Wine - 7. 2017_12_05 Waxhaw Wine 1st Submittal Calcs

SOIL MAP

Hydrologic Soil Group—Union County, North Carolina
(17-035 Waxhaw Wine Soils Map)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/5/2017
Page 1 of 438673203867370386742038674703867520386757038676203867320386737038674203867470386752038675703867620522250522300522350522400522450522500522550522600522650522700522750
522250 522300 522350 522400 522450 522500 522550 522600 522650 522700 522750
34° 57' 3'' N 80° 45' 23'' W34° 57' 3'' N80° 45' 2'' W34° 56' 52'' N
80° 45' 23'' W34° 56' 52'' N
80° 45' 2'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 17N WGS84
0 100 200 400 600
Feet
0 35 70 140 210
Meters
Map Scale: 1:2,390 if printed on A landscape (11" x 8.5") 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: Union County, North Carolina
Survey Area Data: Version 16, 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: Jun 14, 2015—Feb 8,
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—Union County, North Carolina
(17-035 Waxhaw Wine Soils Map)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/5/2017
Page 2 of 4
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
BaC Badin channery silt
loam, 8 to 15 percent
slopes
C 3.1 26.7%
ChA Chewacla silt loam, 0 to
2 percent slopes,
frequently flooded
B/D 7.6 64.5%
TbB2 Tarrus gravelly silty clay
loam, 2 to 8 percent
slopes, moderately
eroded
B 1.0 8.8%
Totals for Area of Interest 11.8 100.0%
Hydrologic Soil Group—Union County, North Carolina 17-035 Waxhaw Wine Soils Map
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/5/2017
Page 3 of 4
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.
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Hydrologic Soil Group—Union County, North Carolina 17-035 Waxhaw Wine Soils Map
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/5/2017
Page 4 of 4

EROSION CONTROL
CALCULATIONS

Waxhaw Wine
JOB NO.:17-035 BY:udp
DATE:12.01.17 P.M.:lbt
REVISED:
RISER/SKIMMER BASIN
DRAINAGE AREAS/REQ'D STORAGE DESIGN CRITERIA
Total Drainage Area (TDA)4.48 ac Proposed sediment depth 3 ft
Disturbed Area (DA)3.79 ac Bottom elevation of basin 501 msl
Required sediment storage (1800xDA) 6,814 cf Side slopes (H:V)3 :1
Required surface area:10,400 sf Depth of flow over spillway 4 ft
BASIN CONFIGURATION PLANNED BASIN SIZE
Bottom elevation 501 msl (REFER TO EROSION CONTROL PLAN)
Sediment Storage elevation 504 msl Elev.Area (SF)Cumulative Volume (CF)
Riser/Primary Spillway crest 505 msl 501 5,320 0
Emergency Spillway crest 508 msl 502 7,546 6,433
Top of Berm 509 msl 503 9,993 15,203
504 12,179 26,289
BASIN EFFICIENCY 505 14,423 39,590
Sediment storage required: 6,814 cf 506 16,724 55,163
Sediment storage provided:39,590 OKAY 507 19,086 73,068
Surface area required: 10,400 sq ft 508 21,504 93,363
Surface area provided:14,423 OKAY 509 23,977 116,104
PRIMARY SPILLWAY DESIGN (2-YEAR STORM)
RISER/PRIMARY SPILLWAY DESIGN
Weighted soil coefficient 'C' =0.55 Riser pipe diameter 48 in
Area 'A' =4.48 ac Depth of flow over riser 4 ft
2 yr. storm rainfall intensity, 'I' =5.03 in/hr
Design flow from site, 'Q' =12 cfs Riser Flow, Q(r):369 cfs OKAY
BARREL PIPE DESIGN
Outlet pipe diameter 18 in
Pipe slope (ft/ft)0.0124 ft/ft Outlet Pipe Flow, Q(p) = 32 cfs
Pipe length(ft)40.3 ft
Outlet pipe invert in 501.00
Outlet pipe invert out 500.50 OUTLET PIPE IS OKAY
EMERGENCY SPILLWAY DESIGN (10-YEAR STORM - Q(PRIMARY SPILLWAY))
Weighted soil coefficient 'C' = 0.55 Depth of flow over spillway 1.0 ft
Area 'A' =4.48 ac
10 yr. storm rainfall intensity, 'I' = 7.03 in/hr Spillway length, L* = 20 ft
Primary Spillway Flow, 'Q(ps)' = 32 cfs
Design flow , 'Q' = -15 Use Min. Spillway Dim.* minimum spillway length is 20 ft
DESIGN FLOW (Q=CIA-Q(ps))SPILLWAY LENGTH (L=Q/(C*h^1.5); C=2.64)
Urban Design Partners
1318-E6 Central Avenue
Charlotte, NC 28205
Skimmer Basin Design
DESIGN FLOW (Q=CIA)

RIP RAP
CALCULATIONS

Figure 8.06a: Design of outlet protection from a round pipe flowing full, minimum
tailwater condition (Tw<0.5 diameter)
18" FES-0:
Q = 4.1 cfs
d0 = 18"
3d0 = 4.5'
La = 10'
w = 11.5'
v = 5.6 fps
d50 = 0.3'
Figure 8.06a: Design of outlet protection from a round pipe flowing full, minimum
tailwater condition (Tw<0.5 diameter)
24" FES-1:
Q = 10.5 cfs
d0 = 24"
3d0 = 6'
La = 13'
w = 15'
v = 6 fps
d50 = 0.4'
Figure 8.06a: Design of outlet protection from a round pipe flowing full, minimum
tailwater condition (Tw<0.5 diameter)
18" FES-20:
Q = 15.9 cfs
d0 = 18"
3d0 = 4.5'
La = 12'
w = 13.5'
v = 5 fps
d50 = 0.3'

STORM DRAINAGE PIPE
CALCULATIONS

Waxhaw WineJOB NO.:17-035BY:udpDATE:12.01.17P.M.:lbtREVISED: LOCATIONDRAINRUNOFFINVERT ELEV.AREAACTUAL (FROM) (FROM) PIPEFROM TO C I Q inlet Q pipe n SLOPE LENGTH SIZE CAPACITY VEL. INV INV RIM COVER MATERIAL(acres) (cfs) (cfs) (%) (ft) (inches) (cfs) (fps) OUT IN ELEVATION DEPTHDI-32 JB-31 0.27 0.60 7.58 1.2 1.2 0.013 1.07% 61156.69 3.71 519.85 519.20 523.50 2.15 III RCPJB-31 FES-30 0.00 0.60 7.58 0.0 1.2 0.013 1.10% 109156.80 3.77 519.20 518.00 523.78 3.08 III RCPCB-23 JB-21 0.28 0.95 7.58 2.0 2.0 0.013 0.58% 43154.94 3.70 505.45 505.20 507.80 1.10 HDPECB-22 JB-21 0.61 0.80 7.58 3.7 3.7 0.013 0.61% 41155.04 4.60 505.45 505.20 509.00 2.30 HDPEJB-21 FES-20 0.00 0.60 7.58 0.0 5.7 0.013 0.56% 35187.92 5.02 505.20 505.00 508.75 2.05 HDPECB-12 CB-6 0.23 0.90 7.58 1.6 1.6 0.013 2.78% 901510.80 5.28 519.50 517.00 523.45 2.70 HDPECB-11 CB-10 0.05 0.90 7.58 0.3 0.3 0.013 0.64% 78155.20 1.95 527.50 527.00 531.50 2.75 HDPECB-10 CB-9 0.54 0.80 7.58 3.3 3.6 0.013 1.68% 119158.40 6.30 527.00 525.00 531.50 3.25 HDPECB-9 DI-8 0.19 0.90 7.58 1.3 4.9 0.013 2.08% 48159.35 7.62 525.00 524.00 530.75 4.50 HDPEDI-8 CB-7 0.16 0.80 7.58 1.0 5.8 0.013 2.45% 611510.14 8.51 519.00 517.50 528.80 8.55 HDPECB-7 CB-6 0.23 0.75 7.58 1.3 7.2 0.013 2.10% 24159.38 8.71 517.50 517.00 521.75 3.00 HDPECB-6 CB-5 0.09 0.98 7.58 0.7 9.4 0.013 2.33% 65159.88 9.74 516.00 514.50 522.00 4.75 HDPECB-5 CB-4 0.19 0.75 7.58 1.1 10.5 0.013 2.73% 421510.71 10.56 514.50 513.35 517.80 2.05 HDPECB-4 CB-3 0.11 0.95 7.58 0.8 11.3 0.013 3.19% 661511.56 11.40 513.35 511.25 517.40 2.80 HDPECB-3 JB-2 0.12 0.75 7.58 0.7 11.9 0.013 1.94% 231814.66 9.62 511.25 510.80 517.20 4.45 HDPEJB-2 FES-1 0.00 0.60 7.58 0.0 11.9 0.013 1.35% 671812.24 8.38 505.90 505.00 517.90 10.50 HDPEOS FES-0 - - - 4.5 4.5 0.013 1.24% 401811.73 5.91 501.00 500.50 507.00 4.21 RCPPIPESTORM DRAINAGE DESIGN DATACharlotte, NC 282051318-E6 Central AvenueUrban Design PartnersVELOCITY

WATER QUALITY
CALCULATIONS

Waxhaw Wine
JOB NO.:17-035 BY:udp
DATE:12.01.17 P.M.:lbt
REVISED:
INTRODUCTION:
SUMMARY
DRAINAGE AREAS:

Predeveloped Drainage Area 4.48 acres
Postdeveloped Drainage Area 4.48 acres
SOIL TYPES:
Area (ac)Area (%)Soil Type Hydrologic Soil Group
1.20 27%BaC C
2.89 65%ChA C
0.39 9%TbB2 B
Total 4.48 100%91% C 9% B
CURVE NUMBER:
Predeveloped CN
Cover Type Area (ac)%CN Wtd. CN
Woods 2.24 50%64 31.85
Grass 2.24 50%67 33.67
Total 4.48 65.52
Composite CN Use CN =66.00
Postdeveloped CN
Cover Type Area (ac)%CN Wtd. CN
Impervious 1.96 44%98 42.91
Grass 2.52 56%67 37.86
Total 4.48 80.76
Composite CN Use CN =81.00
The development includes three commercial buildings and associated parking lots. All stormwater runoff onsite will be
captured by storm drainage system and routed through drainage pipes to a wet pond. The wet pond treats the 1-inch
water quality volume, controls the 1-year 24-hour volume, and controls the 10- and 25-year peak controls. The wet
pond discharges into an existing stream onsite, which later discharges into Twelvemile Creek. The site is currently
wooded with some open space.
Urban Design Partners
PRELIMINARY CALCULATIONS
Charlotte, NC 28205
1318-E6 Central Avenue
HYDROLOGIC CALCULATIONS
Post-developed
Drainage area (DA)4.48 ac.4.48 ac
Cuve Number (CN)66 81
Time of Concentration 0.50 hr.0.08 hr.
Impervious Percentage 0%44%
WATER QUALITY VOLUME (1")
Volume must be released over a period of 2-5 days
Using the runoff volume calculations in the "Simple Method" :
Rv = 0.05 + .009 (I)
Rv=0.44 in/in
WQv = (Design rainfall) (Rv) (Drainage Area)
WQv = 1" rainfall x Rv in/in x 1/12 in/ft x Da = WQv=0.17 ac-ft
7,225 ft3
0.44 in
CHANNEL PROTECTION VOLUME
Q=(P-0.2S)^2/(P+0.8S)
Q=accumulated runoff volume, inches
P=accumulated rainfall (potential maximum runoff), inches 2.58 in
S=potential maximum soil retention, inches = 1000/CN-10 =2.35 in
CN=SCS curve number
Q=1.00 cfs
Compute Watershed Runoff
CPv=0.37 ac-ft
Channel Protection Volume Release Rate (1yr, 24 hr storm)
1.5 day
36 hour
Release=0.126 cfs
Determine Orifice Size for drawdown
Q= CA x sqrt(2gh) orifice equation
aA= Area of orifice a sqft
t= Time to drawdown 129,600 sec 36 hour
g= Gravity constant 32.2 ft/s^2
h= Change in head 1.00 ft
C= Orifice constant 0.6
Maximum orifice area = 0.0261 sq ft
Maximum orifice size =2.19 in.
Pre-developed
Waxhaw Wine
JOB NO.:17-035 BY:udp
DATE:12.01.17 P.M.:lbt
REVISED:
Existing Impervious
Buildings: 0 sf
Sidewalks: 0 sf
Asphalt/Gravel: 0 sf
Total Impervious Area:0 sf
0.00 ac.
Drainage Area:4.48
Impervious Percentage: 0%
Proposed Impervious
Buildings: 11,330 sf
Concrete: 6,070 sf
Asphalt: 64,086 sf
Future Buildings: 4,000 sf
Total Impervious Area:85,486 sf
1.96 ac.
Drainage Area:4.48
Impervious Percentage: 44%
Urban Design Partners
1318-E6 Central Avenue
Charlotte, NC 28205
IMPERVIOUS CALCULATIONS
Waxhaw WineJOB NO.:17-035BY:udpDATE:12.01.17P.M.:lbtREVISED: WATER QUALITY REQUIREMENTS FOR WET POND #1To meet the Water Quality requirements, the procedure outlined in the "Stormwater Best Management Practices"%published by NCDENR will be used. This guide gives the required pond surface area and storage volumeImp.345678to meet an 85% pollutant removal efficiency. Also, the pond must detain the first 1" of rainfall and release10%0.510.430.370.300.270.25this volume over a period of 2 to 5 days. Calculations for these requirements are as follows:20%0.840.690.610.510.440.4030%1.170.940.840.720.610.56Surface area requirements40%1.511.241.090.910.780.71Drainage area to pond (Da)= 4.48Ac50%1.791.511.311.130.950.87Post-development impervious percentage = 44%60%2.091.771.491.311.121.03Average pool depth = 3ft70%2.512.091.801.561.341.17Designed permanent pool elevation = 50580%2.922.412.071.821.621.4090%3.252.642.312.001.841.59From table 1 in the BMP guidelines the required Surface Area to Drainage Area100%3.552.792.522.342.041.75Ratio (SA/DA) for a permanent pool depth of3 ft =1.62Required surface area = SA/DA / 100 x Drainage area=0.072Ac =3,155sfSurface area of pond at permanent pool elevation = 0.241Ac =10,519sf1" rainfall requirementsUsing the runoff volume calculations in the "Simple Method" : Rv = 0.05 + .009 (I)Rv=0.444in/inVolume = (Design rainfall) (Rv) (Drainage Area)Volume = 1" rainfall x Rv in/in x 1/12 in/ft x Da = 0.166ac-ft7,225ft3This volume must be released over a period of 2-5 daysFlow Calculations:Drainage Area: 4.48Ac.Runoff Coefficient:0.62-yr Intensity:5.93in/hr50-yr Intensity:8.95in/hr2-yr Flow:15.95cfs50-yr Flow:24.07cfs10-yr Intensity:7.58in/hr100-yr Intensity:9.46in/hr10-yr Flow:20.39cfs100-yr Flow:25.44cfsUrban Design Partners1318-E6 Central AvenueCharlotte, NC 28205WATER QUALITY DESIGNPERMANENT POOL DEPTH
Waxhaw WineJOB NO.:17-035BY:udpDATE:12.01.17P.M.:lbtREVISED: Urban Design Partners1318-E6 Central AvenueCharlotte, NC 28205WATER QUALITY DESIGNWATER QUALITY BASIN MODELWater Quality Basin Storage VolumesForebay WeirElevation Forebay Main Pool Total Area Total Area Forebay Main Pool Total Volume VolumeElevation = 504.5(msl) Area (sf) Area (sf) (sf) (ac) Volume (cu-ft) Volume (cu-ft) (cu-ft) (ac-ft)Q=3.33lh^3/2501 0 5,579 5,5790.128 0 0 0 0.000Q=2 yr. storm runoff15.95cfs502 1,330 6,521 7,8510.180 0 6,038 6,038 0.153l=weir lengthlft503 1,788 7,488 9,2760.213 1,552 13,030 14,582 0.349h=elevation over weir1.00ft504 2,272 8,480 10,7520.247 3,575 21,001 24,576 0.579l=Q/(3.33 x l^3/2)5052,78210,51913,3010.3056,09530,47336,5680.854Weir Length550616,6380.38251,492 1.19750719,0010.43669,281 1.60550821,4210.49289,459 2.068Average Depth Calculation50923,8970.549112,084 2.58824,054 cf8,986 sf509ft3ftTemporary Pool Elevation (Interpolation)Sediment StorageDetermination of High Water ElevationElevSediment Storage Depth (ft) 1 Q=3.33lh^3/2506Forebay Sediment Vol (cu-ft) 1,552ElevMain Pool Sediment Vol (cu-ft) 6,038 Q= 50 yr. runoff20.39cfs507l= weir length7.64ftTemp. Storage Elev: 0.57 ft. above perm. pool elev.Forebay equals19%h= ht. over weir h ftTemp. Pool Elev:505.57h= (Q/3.33 x l)^2/30.86ftTemp. Pool SA:15,615sfStorage Volume (ac-ft) Storage Area (sf)0.343 16,638*Note: Volume of permanent pool excludes submerged portion of shelfVolume @ Permanent Pool:Perimeter of Perm. Pool @ Bottom:Surface Area of Perm. Pool @ Bottom:Average Depth:of main pool volume0.166 15,6150.751 19,001
Waxhaw WineJOB NO.:17-035BY:udpDATE:12.01.17P.M.:lbtREVISED: Urban Design Partners1318-E6 Central AvenueCharlotte, NC 28205WATER QUALITY DESIGNDetermination of Emergency Spillway Size:Determination of Orifice size for 2-5 day drawdownElevation = 508.0a= 2A x sqrt(h) *Falling head equationQ=3.33lh^3/2Ct(sqrt(2g))a= Area of orificea sqftQ= 100 yr. runoff25.44cfst= Time to drawdown 172,800 sec 2 day min.l= weir length l ftA= Average pond surface area 14,458 sfh= ht. over weir1.00ftg= Gravity constant 32.2 ft/s^2l= Q/(3.33 x l^3/2)h= Change in head0.10 ftLength8ftC= Orifice constant0.6Maximum orifice area = 0.0110 sq ftMaximum orifice size =1.42in.(2 day drawdown)Determination of Emergency Drain 24-hr drawdowna= 2A x sqrt(h) *Falling head equationCt(sqrt(2g))a= Area of orificea sqftt= Time to drawdown 86,400 sec 24-hrA= Average pond surface area 13,301 sfg= Gravity constant 32.2 ft/s^2h= Change in head0.57 ftC= Orifice constant0.6Minimum orifice area = 0.0482 sq ftMinimum orifice size =2.97in.Water SurfacePrePostRoutedElevation1-year1.5010.610.57yes505.75Drawdown time120hr2-year2.7014.491.29yes505.9410-year6.8625.634.52yes506.5525-year9.8232.647.07yes506.9150-year12.3238.2812.04yes507.16100-year15.0844.2819.43no507.35Top of dam elevation: 509.00Emergency Spillway Elevation: 508.00Temporary Pool Elevation: 505.09Drawdown time48hrPermanent Pool Elevation: 505.00Peak Flow (cfs)Peak Flow Controlled?

ROUTING
CALCULATIONS

1
Pre-developed
2
Post-Developed
3
Wet Pond
Routing Diagram for 17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Subcat Reach Pond Link

1-INCH (WQV)
ROUTING

Type II 24-hr 1-inch Rainfall=1.00"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 1: Pre-developed
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 1-inch Rainfall=1.00"
Area (ac) CN Description
* 4.480 66
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry, assumed pre Tc
Subcatchment 1: Pre-developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)1
0
Type II 24-hr
1-inch Rainfall=1.00"
Runoff Area=4.480 ac
Runoff Volume=0.000 af
Runoff Depth=0.00"
Tc=30.0 min
CN=66
0.00 cfs
Type II 24-hr 1-inch Rainfall=1.00"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 2: Post-Developed
Runoff = 0.52 cfs @ 12.00 hrs, Volume= 0.037 af, Depth= 0.10"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 1-inch Rainfall=1.00"
Area (ac) CN Description
* 4.480 81
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post Tc
Subcatchment 2: Post-Developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Type II 24-hr
1-inch Rainfall=1.00"
Runoff Area=4.480 ac
Runoff Volume=0.037 af
Runoff Depth=0.10"
Tc=5.0 min
CN=81
0.52 cfs
Type II 24-hr 1-inch Rainfall=1.00"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 3: Wet Pond
Inflow Area = 4.480 ac, 0.00% Impervious, Inflow Depth = 0.10" for 1-inch event
Inflow = 0.52 cfs @ 12.00 hrs, Volume= 0.037 af
Outflow = 0.01 cfs @ 24.06 hrs, Volume= 0.034 af, Atten= 98%, Lag= 724.1 min
Primary = 0.01 cfs @ 24.06 hrs, Volume= 0.034 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Starting Elev= 505.00' Surf.Area= 13,301 sf Storage= 37,319 cf
Peak Elev= 505.09' @ 24.06 hrs Surf.Area= 13,616 sf Storage= 38,589 cf (1,270 cf above start)
Flood Elev= 509.00' Surf.Area= 23,897 sf Storage= 112,978 cf (75,659 cf above start)
Plug-Flow detention time= (not calculated: initial storage exceeds outflow)
Center-of-Mass det. time= 1,821.0 min ( 2,759.0 - 938.0 )
Volume Invert Avail.Storage Storage Description
#1 501.00' 112,978 cf Wet Pond (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
501.00 5,579 0 0
502.00 7,851 6,715 6,715
503.00 9,276 8,564 15,279
504.00 10,752 10,014 25,293
505.00 13,301 12,027 37,319
506.00 16,638 14,970 52,289
507.00 19,001 17,820 70,108
508.00 21,421 20,211 90,319
509.00 23,897 22,659 112,978
Device Routing Invert Outlet Devices
#1 Primary 501.00'18.0" Round Outlet Pipe L= 52.9' Ke= 0.500
Inlet / Outlet Invert= 501.00' / 500.50' S= 0.0095 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 505.00'1.5" Vert. Low Flow Orifice C= 0.600
#3 Device 1 505.50'Weir Wall, Cv= 3.33 (C= 4.16)
Elev. (feet) 505.50 507.00 507.00
Width (feet) 1.00 1.00 0.00
#4 Device 1 507.00'3.0" x 3.0" Horiz. Grate Top X 16.00 columns
X 16 rows C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Limited to weir flow at low heads
#5 Secondary 508.00'20.0' long x 10.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Type II 24-hr 1-inch Rainfall=1.00"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Primary OutFlow Max=0.01 cfs @ 24.06 hrs HW=505.09' (Free Discharge)
1=Outlet Pipe (Passes 0.01 cfs of 15.56 cfs potential flow)
2=Low Flow Orifice (Orifice Controls 0.01 cfs @ 1.05 fps)
3=Weir Wall ( Controls 0.00 cfs)
4=Grate Top ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge)
5=Emergency Spillway ( Controls 0.00 cfs)
Pond 3: Wet Pond
Inflow
Outflow
Primary
Secondary
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Inflow Area=4.480 ac
Peak Elev=505.09'
Storage=38,589 cf
0.52 cfs
0.01 cfs
0.01 cfs
0.00 cfs
Type II 24-hr 1-inch Rainfall=1.00"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Hydrograph for Pond 3: Wet Pond
Time
(hours)
Inflow
(cfs)
Storage
(cubic-feet)
Elevation
(feet)
Outflow
(cfs)
Primary
(cfs)
Secondary
(cfs)
0.00 0.00 37,319 505.00 0.00 0.00 0.00
4.00 0.00 37,319 505.00 0.00 0.00 0.00
8.00 0.00 37,319 505.00 0.00 0.00 0.00
12.00 0.51 37,441 505.01 0.00 0.00 0.00
16.00 0.03 38,236 505.07 0.01 0.01 0.00
20.00 0.02 38,470 505.09 0.01 0.01 0.00
24.00 0.02 38,589 505.09 0.01 0.01 0.00
28.00 0.00 38,461 505.08 0.01 0.01 0.00
32.00 0.00 38,345 505.08 0.01 0.01 0.00
36.00 0.00 38,240 505.07 0.01 0.01 0.00
40.00 0.00 38,147 505.06 0.01 0.01 0.00
44.00 0.00 38,063 505.06 0.01 0.01 0.00
48.00 0.00 37,987 505.05 0.00 0.00 0.00
52.00 0.00 37,920 505.04 0.00 0.00 0.00
56.00 0.00 37,859 505.04 0.00 0.00 0.00
60.00 0.00 37,804 505.04 0.00 0.00 0.00
64.00 0.00 37,755 505.03 0.00 0.00 0.00
68.00 0.00 37,710 505.03 0.00 0.00 0.00
72.00 0.00 37,671 505.03 0.00 0.00 0.00
76.00 0.00 37,635 505.02 0.00 0.00 0.00
80.00 0.00 37,603 505.02 0.00 0.00 0.00
84.00 0.00 37,574 505.02 0.00 0.00 0.00
88.00 0.00 37,548 505.02 0.00 0.00 0.00
92.00 0.00 37,525 505.02 0.00 0.00 0.00
96.00 0.00 37,504 505.01 0.00 0.00 0.00
100.00 0.00 37,485 505.01 0.00 0.00 0.00
104.00 0.00 37,468 505.01 0.00 0.00 0.00
108.00 0.00 37,453 505.01 0.00 0.00 0.00
112.00 0.00 37,440 505.01 0.00 0.00 0.00
116.00 0.00 37,427 505.01 0.00 0.00 0.00
120.00 0.00 37,416 505.01 0.00 0.00 0.00
1-inch (WQv)
Drawdown: 48 hr

1-YEAR
ROUTING

Type II 24-hr 1-yr Rainfall=2.95"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 1: Pre-developed
Runoff = 1.50 cfs @ 12.30 hrs, Volume= 0.195 af, Depth= 0.52"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 1-yr Rainfall=2.95"
Area (ac) CN Description
* 4.480 66
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry, assumed pre Tc
Subcatchment 1: Pre-developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)1
0
Type II 24-hr
1-yr Rainfall=2.95"
Runoff Area=4.480 ac
Runoff Volume=0.195 af
Runoff Depth=0.52"
Tc=30.0 min
CN=66
1.50 cfs
Type II 24-hr 1-yr Rainfall=2.95"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 2: Post-Developed
Runoff = 10.61 cfs @ 11.96 hrs, Volume= 0.476 af, Depth= 1.28"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 1-yr Rainfall=2.95"
Area (ac) CN Description
* 4.480 81
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post Tc
Subcatchment 2: Post-Developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)11
10
9
8
7
6
5
4
3
2
1
0
Type II 24-hr
1-yr Rainfall=2.95"
Runoff Area=4.480 ac
Runoff Volume=0.476 af
Runoff Depth=1.28"
Tc=5.0 min
CN=81
10.61 cfs
Type II 24-hr 1-yr Rainfall=2.95"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 3: Wet Pond
Inflow Area = 4.480 ac, 0.00% Impervious, Inflow Depth = 1.28" for 1-yr event
Inflow = 10.61 cfs @ 11.96 hrs, Volume= 0.476 af
Outflow = 0.57 cfs @ 13.03 hrs, Volume= 0.462 af, Atten= 95%, Lag= 64.0 min
Primary = 0.57 cfs @ 13.03 hrs, Volume= 0.462 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Starting Elev= 505.00' Surf.Area= 13,301 sf Storage= 37,319 cf
Peak Elev= 505.75' @ 13.03 hrs Surf.Area= 15,804 sf Storage= 48,237 cf (10,918 cf above start)
Flood Elev= 509.00' Surf.Area= 23,897 sf Storage= 112,978 cf (75,659 cf above start)
Plug-Flow detention time= (not calculated: initial storage exceeds outflow)
Center-of-Mass det. time= 1,006.8 min ( 1,846.3 - 839.5 )
Volume Invert Avail.Storage Storage Description
#1 501.00' 112,978 cf Wet Pond (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
501.00 5,579 0 0
502.00 7,851 6,715 6,715
503.00 9,276 8,564 15,279
504.00 10,752 10,014 25,293
505.00 13,301 12,027 37,319
506.00 16,638 14,970 52,289
507.00 19,001 17,820 70,108
508.00 21,421 20,211 90,319
509.00 23,897 22,659 112,978
Device Routing Invert Outlet Devices
#1 Primary 501.00'18.0" Round Outlet Pipe L= 52.9' Ke= 0.500
Inlet / Outlet Invert= 501.00' / 500.50' S= 0.0095 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 505.00'1.5" Vert. Low Flow Orifice C= 0.600
#3 Device 1 505.50'Weir Wall, Cv= 3.33 (C= 4.16)
Elev. (feet) 505.50 507.00 507.00
Width (feet) 1.00 1.00 0.00
#4 Device 1 507.00'3.0" x 3.0" Horiz. Grate Top X 16.00 columns
X 16 rows C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Limited to weir flow at low heads
#5 Secondary 508.00'20.0' long x 10.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Type II 24-hr 1-yr Rainfall=2.95"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Primary OutFlow Max=0.57 cfs @ 13.03 hrs HW=505.75' (Free Discharge)
1=Outlet Pipe (Passes 0.57 cfs of 17.02 cfs potential flow)
2=Low Flow Orifice (Orifice Controls 0.05 cfs @ 3.99 fps)
3=Weir Wall (Weir Controls 0.52 cfs @ 2.08 fps)
4=Grate Top ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge)
5=Emergency Spillway ( Controls 0.00 cfs)
Pond 3: Wet Pond
Inflow
Outflow
Primary
Secondary
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)11
10
9
8
7
6
5
4
3
2
1
0
Inflow Area=4.480 ac
Peak Elev=505.75'
Storage=48,237 cf
10.61 cfs
0.57 cfs
0.57 cfs
0.00 cfs
Type II 24-hr 1-yr Rainfall=2.95"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Hydrograph for Pond 3: Wet Pond
Time
(hours)
Inflow
(cfs)
Storage
(cubic-feet)
Elevation
(feet)
Outflow
(cfs)
Primary
(cfs)
Secondary
(cfs)
0.00 0.00 37,319 505.00 0.00 0.00 0.00
4.00 0.00 37,319 505.00 0.00 0.00 0.00
8.00 0.00 37,319 505.00 0.00 0.00 0.00
12.00 9.27 44,776 505.53 0.07 0.07 0.00
16.00 0.23 46,979 505.67 0.34 0.34 0.00
20.00 0.13 45,942 505.60 0.19 0.19 0.00
24.00 0.11 45,493 505.57 0.13 0.13 0.00
28.00 0.00 44,440 505.50 0.04 0.04 0.00
32.00 0.00 43,885 505.47 0.04 0.04 0.00
36.00 0.00 43,357 505.43 0.04 0.04 0.00
40.00 0.00 42,854 505.40 0.03 0.03 0.00
44.00 0.00 42,375 505.36 0.03 0.03 0.00
48.00 0.00 41,922 505.33 0.03 0.03 0.00
52.00 0.00 41,493 505.30 0.03 0.03 0.00
56.00 0.00 41,091 505.27 0.03 0.03 0.00
60.00 0.00 40,713 505.25 0.03 0.03 0.00
64.00 0.00 40,361 505.22 0.02 0.02 0.00
68.00 0.00 40,037 505.20 0.02 0.02 0.00
72.00 0.00 39,738 505.18 0.02 0.02 0.00
76.00 0.00 39,464 505.16 0.02 0.02 0.00
80.00 0.00 39,219 505.14 0.02 0.02 0.00
84.00 0.00 39,005 505.12 0.01 0.01 0.00
88.00 0.00 38,819 505.11 0.01 0.01 0.00
92.00 0.00 38,657 505.10 0.01 0.01 0.00
96.00 0.00 38,516 505.09 0.01 0.01 0.00
100.00 0.00 38,393 505.08 0.01 0.01 0.00
104.00 0.00 38,284 505.07 0.01 0.01 0.00
108.00 0.00 38,186 505.06 0.01 0.01 0.00
112.00 0.00 38,098 505.06 0.01 0.01 0.00
116.00 0.00 38,019 505.05 0.01 0.01 0.00
120.00 0.00 37,948 505.05 0.00 0.00 0.00
1-year 24-hour
Drawdown: 120 hr

2-YEAR
ROUTING

Type II 24-hr 2-yr Rainfall=3.55"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 1: Pre-developed
Runoff = 2.70 cfs @ 12.29 hrs, Volume= 0.309 af, Depth= 0.83"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 2-yr Rainfall=3.55"
Area (ac) CN Description
* 4.480 66
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry, assumed pre Tc
Subcatchment 1: Pre-developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)3
2
1
0
Type II 24-hr
2-yr Rainfall=3.55"
Runoff Area=4.480 ac
Runoff Volume=0.309 af
Runoff Depth=0.83"
Tc=30.0 min
CN=66
2.70 cfs
Type II 24-hr 2-yr Rainfall=3.55"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 2: Post-Developed
Runoff = 14.49 cfs @ 11.96 hrs, Volume= 0.653 af, Depth= 1.75"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 2-yr Rainfall=3.55"
Area (ac) CN Description
* 4.480 81
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post Tc
Subcatchment 2: Post-Developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Type II 24-hr
2-yr Rainfall=3.55"
Runoff Area=4.480 ac
Runoff Volume=0.653 af
Runoff Depth=1.75"
Tc=5.0 min
CN=81
14.49 cfs
Type II 24-hr 2-yr Rainfall=3.55"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 3: Wet Pond
Inflow Area = 4.480 ac, 0.00% Impervious, Inflow Depth = 1.75" for 2-yr event
Inflow = 14.49 cfs @ 11.96 hrs, Volume= 0.653 af
Outflow = 1.29 cfs @ 12.47 hrs, Volume= 0.638 af, Atten= 91%, Lag= 30.4 min
Primary = 1.29 cfs @ 12.47 hrs, Volume= 0.638 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Starting Elev= 505.00' Surf.Area= 13,301 sf Storage= 37,319 cf
Peak Elev= 505.94' @ 12.47 hrs Surf.Area= 16,452 sf Storage= 51,368 cf (14,049 cf above start)
Flood Elev= 509.00' Surf.Area= 23,897 sf Storage= 112,978 cf (75,659 cf above start)
Plug-Flow detention time= (not calculated: initial storage exceeds outflow)
Center-of-Mass det. time= 760.4 min ( 1,590.7 - 830.3 )
Volume Invert Avail.Storage Storage Description
#1 501.00' 112,978 cf Wet Pond (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
501.00 5,579 0 0
502.00 7,851 6,715 6,715
503.00 9,276 8,564 15,279
504.00 10,752 10,014 25,293
505.00 13,301 12,027 37,319
506.00 16,638 14,970 52,289
507.00 19,001 17,820 70,108
508.00 21,421 20,211 90,319
509.00 23,897 22,659 112,978
Device Routing Invert Outlet Devices
#1 Primary 501.00'18.0" Round Outlet Pipe L= 52.9' Ke= 0.500
Inlet / Outlet Invert= 501.00' / 500.50' S= 0.0095 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 505.00'1.5" Vert. Low Flow Orifice C= 0.600
#3 Device 1 505.50'Weir Wall, Cv= 3.33 (C= 4.16)
Elev. (feet) 505.50 507.00 507.00
Width (feet) 1.00 1.00 0.00
#4 Device 1 507.00'3.0" x 3.0" Horiz. Grate Top X 16.00 columns
X 16 rows C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Limited to weir flow at low heads
#5 Secondary 508.00'20.0' long x 10.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Type II 24-hr 2-yr Rainfall=3.55"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Primary OutFlow Max=1.29 cfs @ 12.47 hrs HW=505.94' (Free Discharge)
1=Outlet Pipe (Passes 1.29 cfs of 17.43 cfs potential flow)
2=Low Flow Orifice (Orifice Controls 0.06 cfs @ 4.52 fps)
3=Weir Wall (Weir Controls 1.23 cfs @ 2.77 fps)
4=Grate Top ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge)
5=Emergency Spillway ( Controls 0.00 cfs)
Pond 3: Wet Pond
Inflow
Outflow
Primary
Secondary
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Inflow Area=4.480 ac
Peak Elev=505.94'
Storage=51,368 cf
14.49 cfs
1.29 cfs
1.29 cfs
0.00 cfs

10-YEAR
ROUTING

Type II 24-hr 10-yr Rainfall=5.19"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 1: Pre-developed
Runoff = 6.86 cfs @ 12.26 hrs, Volume= 0.694 af, Depth= 1.86"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 10-yr Rainfall=5.19"
Area (ac) CN Description
* 4.480 66
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry, assumed pre Tc
Subcatchment 1: Pre-developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)7
6
5
4
3
2
1
0
Type II 24-hr
10-yr Rainfall=5.19"
Runoff Area=4.480 ac
Runoff Volume=0.694 af
Runoff Depth=1.86"
Tc=30.0 min
CN=66
6.86 cfs
Type II 24-hr 10-yr Rainfall=5.19"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 2: Post-Developed
Runoff = 25.63 cfs @ 11.96 hrs, Volume= 1.177 af, Depth= 3.15"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 10-yr Rainfall=5.19"
Area (ac) CN Description
* 4.480 81
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post Tc
Subcatchment 2: Post-Developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Type II 24-hr
10-yr Rainfall=5.19"
Runoff Area=4.480 ac
Runoff Volume=1.177 af
Runoff Depth=3.15"
Tc=5.0 min
CN=81
25.63 cfs
Type II 24-hr 10-yr Rainfall=5.19"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 3: Wet Pond
Inflow Area = 4.480 ac, 0.00% Impervious, Inflow Depth = 3.15" for 10-yr event
Inflow = 25.63 cfs @ 11.96 hrs, Volume= 1.177 af
Outflow = 4.52 cfs @ 12.13 hrs, Volume= 1.162 af, Atten= 82%, Lag= 9.9 min
Primary = 4.52 cfs @ 12.13 hrs, Volume= 1.162 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Starting Elev= 505.00' Surf.Area= 13,301 sf Storage= 37,319 cf
Peak Elev= 506.55' @ 12.13 hrs Surf.Area= 17,927 sf Storage= 61,715 cf (24,396 cf above start)
Flood Elev= 509.00' Surf.Area= 23,897 sf Storage= 112,978 cf (75,659 cf above start)
Plug-Flow detention time= 1,793.2 min calculated for 0.306 af (26% of inflow)
Center-of-Mass det. time= 460.4 min ( 1,273.9 - 813.5 )
Volume Invert Avail.Storage Storage Description
#1 501.00' 112,978 cf Wet Pond (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
501.00 5,579 0 0
502.00 7,851 6,715 6,715
503.00 9,276 8,564 15,279
504.00 10,752 10,014 25,293
505.00 13,301 12,027 37,319
506.00 16,638 14,970 52,289
507.00 19,001 17,820 70,108
508.00 21,421 20,211 90,319
509.00 23,897 22,659 112,978
Device Routing Invert Outlet Devices
#1 Primary 501.00'18.0" Round Outlet Pipe L= 52.9' Ke= 0.500
Inlet / Outlet Invert= 501.00' / 500.50' S= 0.0095 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 505.00'1.5" Vert. Low Flow Orifice C= 0.600
#3 Device 1 505.50'Weir Wall, Cv= 3.33 (C= 4.16)
Elev. (feet) 505.50 507.00 507.00
Width (feet) 1.00 1.00 0.00
#4 Device 1 507.00'3.0" x 3.0" Horiz. Grate Top X 16.00 columns
X 16 rows C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Limited to weir flow at low heads
#5 Secondary 508.00'20.0' long x 10.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Type II 24-hr 10-yr Rainfall=5.19"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Primary OutFlow Max=4.52 cfs @ 12.13 hrs HW=506.55' (Free Discharge)
1=Outlet Pipe (Passes 4.52 cfs of 18.63 cfs potential flow)
2=Low Flow Orifice (Orifice Controls 0.07 cfs @ 5.86 fps)
3=Weir Wall (Weir Controls 4.45 cfs @ 4.26 fps)
4=Grate Top ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge)
5=Emergency Spillway ( Controls 0.00 cfs)
Pond 3: Wet Pond
Inflow
Outflow
Primary
Secondary
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Inflow Area=4.480 ac
Peak Elev=506.55'
Storage=61,715 cf
25.63 cfs
4.52 cfs
4.52 cfs
0.00 cfs

25-YEAR
ROUTING

Type II 24-hr 25-yr Rainfall=6.20"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 1: Pre-developed
Runoff = 9.82 cfs @ 12.25 hrs, Volume= 0.967 af, Depth= 2.59"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 25-yr Rainfall=6.20"
Area (ac) CN Description
* 4.480 66
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry, assumed pre Tc
Subcatchment 1: Pre-developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)10
9
8
7
6
5
4
3
2
1
0
Type II 24-hr
25-yr Rainfall=6.20"
Runoff Area=4.480 ac
Runoff Volume=0.967 af
Runoff Depth=2.59"
Tc=30.0 min
CN=66
9.82 cfs
Type II 24-hr 25-yr Rainfall=6.20"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 2: Post-Developed
Runoff = 32.64 cfs @ 11.96 hrs, Volume= 1.518 af, Depth= 4.07"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 25-yr Rainfall=6.20"
Area (ac) CN Description
* 4.480 81
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post Tc
Subcatchment 2: Post-Developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Type II 24-hr
25-yr Rainfall=6.20"
Runoff Area=4.480 ac
Runoff Volume=1.518 af
Runoff Depth=4.07"
Tc=5.0 min
CN=81
32.64 cfs
Type II 24-hr 25-yr Rainfall=6.20"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 3: Wet Pond
Inflow Area = 4.480 ac, 0.00% Impervious, Inflow Depth = 4.07" for 25-yr event
Inflow = 32.64 cfs @ 11.96 hrs, Volume= 1.518 af
Outflow = 7.07 cfs @ 12.10 hrs, Volume= 1.503 af, Atten= 78%, Lag= 8.5 min
Primary = 7.07 cfs @ 12.10 hrs, Volume= 1.503 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Starting Elev= 505.00' Surf.Area= 13,301 sf Storage= 37,319 cf
Peak Elev= 506.91' @ 12.10 hrs Surf.Area= 18,795 sf Storage= 68,460 cf (31,141 cf above start)
Flood Elev= 509.00' Surf.Area= 23,897 sf Storage= 112,978 cf (75,659 cf above start)
Plug-Flow detention time= 1,031.9 min calculated for 0.646 af (43% of inflow)
Center-of-Mass det. time= 374.8 min ( 1,181.1 - 806.3 )
Volume Invert Avail.Storage Storage Description
#1 501.00' 112,978 cf Wet Pond (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
501.00 5,579 0 0
502.00 7,851 6,715 6,715
503.00 9,276 8,564 15,279
504.00 10,752 10,014 25,293
505.00 13,301 12,027 37,319
506.00 16,638 14,970 52,289
507.00 19,001 17,820 70,108
508.00 21,421 20,211 90,319
509.00 23,897 22,659 112,978
Device Routing Invert Outlet Devices
#1 Primary 501.00'18.0" Round Outlet Pipe L= 52.9' Ke= 0.500
Inlet / Outlet Invert= 501.00' / 500.50' S= 0.0095 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 505.00'1.5" Vert. Low Flow Orifice C= 0.600
#3 Device 1 505.50'Weir Wall, Cv= 3.33 (C= 4.16)
Elev. (feet) 505.50 507.00 507.00
Width (feet) 1.00 1.00 0.00
#4 Device 1 507.00'3.0" x 3.0" Horiz. Grate Top X 16.00 columns
X 16 rows C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Limited to weir flow at low heads
#5 Secondary 508.00'20.0' long x 10.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Type II 24-hr 25-yr Rainfall=6.20"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Primary OutFlow Max=7.07 cfs @ 12.10 hrs HW=506.91' (Free Discharge)
1=Outlet Pipe (Passes 7.07 cfs of 19.33 cfs potential flow)
2=Low Flow Orifice (Orifice Controls 0.08 cfs @ 6.55 fps)
3=Weir Wall (Weir Controls 6.99 cfs @ 4.95 fps)
4=Grate Top ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge)
5=Emergency Spillway ( Controls 0.00 cfs)
Pond 3: Wet Pond
Inflow
Outflow
Primary
Secondary
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Inflow Area=4.480 ac
Peak Elev=506.91'
Storage=68,460 cf
32.64 cfs
7.07 cfs
7.07 cfs
0.00 cfs

50-YEAR
ROUTING

Type II 24-hr 50-yr Rainfall=7.01"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 1: Pre-developed
Runoff = 12.32 cfs @ 12.25 hrs, Volume= 1.199 af, Depth= 3.21"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 50-yr Rainfall=7.01"
Area (ac) CN Description
* 4.480 66
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry, assumed pre Tc
Subcatchment 1: Pre-developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)13
12
11
10
9
8
7
6
5
4
3
2
1
0
Type II 24-hr
50-yr Rainfall=7.01"
Runoff Area=4.480 ac
Runoff Volume=1.199 af
Runoff Depth=3.21"
Tc=30.0 min
CN=66
12.32 cfs
Type II 24-hr 50-yr Rainfall=7.01"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 2: Post-Developed
Runoff = 38.28 cfs @ 11.96 hrs, Volume= 1.797 af, Depth= 4.81"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 50-yr Rainfall=7.01"
Area (ac) CN Description
* 4.480 81
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post Tc
Subcatchment 2: Post-Developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Type II 24-hr
50-yr Rainfall=7.01"
Runoff Area=4.480 ac
Runoff Volume=1.797 af
Runoff Depth=4.81"
Tc=5.0 min
CN=81
38.28 cfs
Type II 24-hr 50-yr Rainfall=7.01"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 3: Wet Pond
Inflow Area = 4.480 ac, 0.00% Impervious, Inflow Depth = 4.81" for 50-yr event
Inflow = 38.28 cfs @ 11.96 hrs, Volume= 1.797 af
Outflow = 12.04 cfs @ 12.07 hrs, Volume= 1.782 af, Atten= 69%, Lag= 6.8 min
Primary = 12.04 cfs @ 12.07 hrs, Volume= 1.782 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Starting Elev= 505.00' Surf.Area= 13,301 sf Storage= 37,319 cf
Peak Elev= 507.16' @ 12.07 hrs Surf.Area= 19,386 sf Storage= 73,162 cf (35,843 cf above start)
Flood Elev= 509.00' Surf.Area= 23,897 sf Storage= 112,978 cf (75,659 cf above start)
Plug-Flow detention time= 790.0 min calculated for 0.925 af (51% of inflow)
Center-of-Mass det. time= 327.7 min ( 1,129.1 - 801.5 )
Volume Invert Avail.Storage Storage Description
#1 501.00' 112,978 cf Wet Pond (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
501.00 5,579 0 0
502.00 7,851 6,715 6,715
503.00 9,276 8,564 15,279
504.00 10,752 10,014 25,293
505.00 13,301 12,027 37,319
506.00 16,638 14,970 52,289
507.00 19,001 17,820 70,108
508.00 21,421 20,211 90,319
509.00 23,897 22,659 112,978
Device Routing Invert Outlet Devices
#1 Primary 501.00'18.0" Round Outlet Pipe L= 52.9' Ke= 0.500
Inlet / Outlet Invert= 501.00' / 500.50' S= 0.0095 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 505.00'1.5" Vert. Low Flow Orifice C= 0.600
#3 Device 1 505.50'Weir Wall, Cv= 3.33 (C= 4.16)
Elev. (feet) 505.50 507.00 507.00
Width (feet) 1.00 1.00 0.00
#4 Device 1 507.00'3.0" x 3.0" Horiz. Grate Top X 16.00 columns
X 16 rows C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Limited to weir flow at low heads
#5 Secondary 508.00'20.0' long x 10.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Type II 24-hr 50-yr Rainfall=7.01"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Primary OutFlow Max=11.99 cfs @ 12.07 hrs HW=507.16' (Free Discharge)
1=Outlet Pipe (Passes 11.99 cfs of 19.79 cfs potential flow)
2=Low Flow Orifice (Orifice Controls 0.09 cfs @ 6.97 fps)
3=Weir Wall (Orifice Controls 8.62 cfs @ 5.75 fps)
4=Grate Top (Weir Controls 3.28 cfs @ 1.30 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge)
5=Emergency Spillway ( Controls 0.00 cfs)
Pond 3: Wet Pond
Inflow
Outflow
Primary
Secondary
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Inflow Area=4.480 ac
Peak Elev=507.16'
Storage=73,162 cf
38.28 cfs
12.04 cfs
12.04 cfs
0.00 cfs

100-YEAR
ROUTING

Type II 24-hr 100-yr Rainfall=7.87"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 1: Pre-developed
Runoff = 15.08 cfs @ 12.24 hrs, Volume= 1.456 af, Depth= 3.90"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 100-yr Rainfall=7.87"
Area (ac) CN Description
* 4.480 66
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry, assumed pre Tc
Subcatchment 1: Pre-developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Type II 24-hr
100-yr Rainfall=7.87"
Runoff Area=4.480 ac
Runoff Volume=1.456 af
Runoff Depth=3.90"
Tc=30.0 min
CN=66
15.08 cfs
Type II 24-hr 100-yr Rainfall=7.87"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Subcatchment 2: Post-Developed
Runoff = 44.28 cfs @ 11.96 hrs, Volume= 2.098 af, Depth= 5.62"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Type II 24-hr 100-yr Rainfall=7.87"
Area (ac) CN Description
* 4.480 81
4.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post Tc
Subcatchment 2: Post-Developed
Runoff
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Type II 24-hr
100-yr Rainfall=7.87"
Runoff Area=4.480 ac
Runoff Volume=2.098 af
Runoff Depth=5.62"
Tc=5.0 min
CN=81
44.28 cfs
Type II 24-hr 100-yr Rainfall=7.87"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 3: Wet Pond
Inflow Area = 4.480 ac, 0.00% Impervious, Inflow Depth = 5.62" for 100-yr event
Inflow = 44.28 cfs @ 11.96 hrs, Volume= 2.098 af
Outflow = 19.43 cfs @ 12.05 hrs, Volume= 2.083 af, Atten= 56%, Lag= 5.6 min
Primary = 19.43 cfs @ 12.05 hrs, Volume= 2.083 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Starting Elev= 505.00' Surf.Area= 13,301 sf Storage= 37,319 cf
Peak Elev= 507.35' @ 12.05 hrs Surf.Area= 19,841 sf Storage= 76,846 cf (39,527 cf above start)
Flood Elev= 509.00' Surf.Area= 23,897 sf Storage= 112,978 cf (75,659 cf above start)
Plug-Flow detention time= 642.3 min calculated for 1.226 af (58% of inflow)
Center-of-Mass det. time= 289.3 min ( 1,086.4 - 797.1 )
Volume Invert Avail.Storage Storage Description
#1 501.00' 112,978 cf Wet Pond (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
501.00 5,579 0 0
502.00 7,851 6,715 6,715
503.00 9,276 8,564 15,279
504.00 10,752 10,014 25,293
505.00 13,301 12,027 37,319
506.00 16,638 14,970 52,289
507.00 19,001 17,820 70,108
508.00 21,421 20,211 90,319
509.00 23,897 22,659 112,978
Device Routing Invert Outlet Devices
#1 Primary 501.00'18.0" Round Outlet Pipe L= 52.9' Ke= 0.500
Inlet / Outlet Invert= 501.00' / 500.50' S= 0.0095 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 505.00'1.5" Vert. Low Flow Orifice C= 0.600
#3 Device 1 505.50'Weir Wall, Cv= 3.33 (C= 4.16)
Elev. (feet) 505.50 507.00 507.00
Width (feet) 1.00 1.00 0.00
#4 Device 1 507.00'3.0" x 3.0" Horiz. Grate Top X 16.00 columns
X 16 rows C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Limited to weir flow at low heads
#5 Secondary 508.00'20.0' long x 10.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Type II 24-hr 100-yr Rainfall=7.87"17-035 Wet Pond
Prepared by Urban Design Partners
HydroCAD® 10.00-20 s/n 09103 © 2017 HydroCAD Software Solutions LLC
Primary OutFlow Max=20.13 cfs @ 12.05 hrs HW=507.34' (Free Discharge)
1=Outlet Pipe (Inlet Controls 20.13 cfs @ 11.39 fps)
2=Low Flow Orifice (Passes < 0.09 cfs potential flow)
3=Weir Wall (Passes < 9.59 cfs potential flow)
4=Grate Top (Passes < 10.58 cfs potential flow)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=505.00' (Free Discharge)
5=Emergency Spillway ( Controls 0.00 cfs)
Pond 3: Wet Pond
Inflow
Outflow
Primary
Secondary
Hydrograph
Time (hours)
12011511010510095908580757065605550454035302520151050Flow (cfs)45
40
35
30
25
20
15
10
5
0
Inflow Area=4.480 ac
Peak Elev=507.35'
Storage=76,846 cf
44.28 cfs
19.43 cfs
19.43 cfs
0.00 cfs