SW3220801_Design Calculations_20231027

ENGINEERING CALCULATIONS
FOR
STONEBOW RETAIL CENTER
UNION COUNTY, NORTH CAROLINA
Beulah Church Road Developers, LLC
5615 Potter Road
Matthews, NC 28104
June 2022
Revised August 2022
Revised March 2023
Revised June 2023
Revised July 2023
Revised August 2023
Revised September 2023
Revised October 2023
LandDesign Project #: 1018342
Calculated By: DMG
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SEAL
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10/25/2023
LandDesign

TABLE OF CONTENTS
• PROJECT NARRATIVE
• USGS MAP
• SOILS MAP
• FLOOD MAP
• DRAINAGE AREA MAPS
• SEDIMENT BASIN CALUCLATIONS
• TEMPORARY SLOPE DRAIN CALCULATIONS
• TEMPORARY DIVERSION DITCH CALCULATIONS
• PRE DEVELOPED CALCULATIONS
• POST DEVELOPED CALCULATIONS
• WATER QUALITY CALCULATIONS
• BMP CALCULATIONS
• BIORETENTION CALCULATION
• BOUYANCY CALCULATIONS
• RIP RAP CALCULATIONS
• STORM DRAINAGE CALCULATIONS
• STORM DRAINAGE CALCULATIONS - 10 YEAR
• SPREAD CALCULATIONS
• OFFSITE DRAINAGE CALCULATIONS

Project Narrative:

Stonebow
LDI Project No. 1018342
Developer:
Beulah Church Road Developers, LLC
5615 Potter Road
Matthews, NC 28104
Project Description:
The following calculations have been performed in support of the construction of Stonebow
Retail Center. The project is zoned B-2 in unincorporated Union County, NC. The
construction will include installation of new buildings, associated utilities, storm drainage,
wet pond, bioretention BMP, and offsite roadway improvements.
Soils Information:
The predominant soils for this site are BdB2 & GsB. The site soils map showing detailed
locations is included. For design purposes, "C" & "D" were used as the hydrologic soil
groups.
Pre-Developed Drainage:
The existing storm water collection system consists of sheet flow, shallow concentrated, and
open channel flow.
Post-Developed Drainage:
The proposed storm water collection system will consist of drainage swales and one wet
pond within the project boundaries. The storm system was designed to detain the 10 and 25
year storm events and to have a minimum of 85% average annual removal for Total
Suspended Solids and 40% average annual removal for Total Phosphorus. Proposed water
quality/channel protection/detention requirements are being met according to the NCDEQ
Requirements.

Stormwater Detention Summary:
Drainage Area: 3.59 acres
Q2 (Pre-Developed): 10.12 cfs
Q,o (Pre-Developed): 18.79 cfs
Q25 (Pre-Developed): 24.33 cfs
Q2 (Post-Developed BMP) Detained Detention Release: 1.37 cfs
Q10 (Post-Developed BMP) Detained Detention Release: 2.78 cfs
Q25 (Post-Developed BMP) Detained Detention Release: 3.37 cfs
Q2 (Post-Developed Undetained Area): 1.10 cfs
Q,o (Post-Developed Undetained Area): 2.17 cfs
Q25 (Post-Developed Undetained Area): 2.87 cfs
Q2 (Post-Developed Total): 1.37 + 1.10 = 2.47 cfs
Q,o (Post-Developed Total): 2.78 + 2.17 = 4.95 cfs
Q25 (Post-Developed Total): 3.37 + 2.87 = 6.24 cfs
Q2 (Post-Developed vs. Pre-Developed): 2.47 cfs < 10.12 cfs
Q,o (Post-Developed vs. Pre-Developed): 4.95 cfs < 18.79 cfs
Q25 (Post-Developed vs. Pre-Developed): 6.24 cfs < 24.33 cfs
Conclusion:
The engineering analysis presented herein this document demonstrates the ability of the
Wet Ponds to meet the design requirements. The calculations show the Wet Pond has
sufficient volume to meet the NCDEQ's requirements for BMPs. Moreover, the routing
calculations show the Wet Pond's ability to detain flows to pre-developed rates.

USGS Map:

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Sources: Esri, HERE,Garmin, Intermap, increment P Corp., GEBCO,
USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance
Survey, Esri Japan, METI, Esri China (Hong Kong), (c)
OpenStreetMap contributors,and the GIS User Community
USGS
2021 USGS

Soils Map:

Hydrologic Soil Group—Union County,North Carolina
a (Stonebow) 7,7-1
527650 527670 527690 527710 527730 527750 52///0 527790 527810 527830 527850 527870 527890
35°1'9"N —- r . J I 35°1'9"N
o ..... . -• 1- - - —-- ' - o
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8 Beulah - . �3
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35°14 N I R 35°14N
527650 527670 527690 527710 527730 527750 527770 527790 527810 527830 527850 527870 527890
3 3
v Map Scale:1:1,210 if printed on A landscape(11"x 8.5")sheet.
Meters
m N 0 15 30 60 90 m
Feet
0 50 100 200 300
Map projection:Web Mercator Corner000rdinates:WG584 Edge tics:UTM Zone 17N WGS84
USDA Natural Resources Web Soil Survey 6/1/2022
aid Conservation Service National Cooperative Soil Survey Page 1 of 4

Hydrologic Soil Group—Union County,North Carolina
(Stonebow)
MAP LEGEND MAP INFORMATION
Area of Interest(AOI) p c The soil surveys that comprise your AOI were mapped at
Area of Interest(AOI) 1:24,000.
0 CID
Soils • D Warning:Soil Map may not be valid at this scale.
Soil Rating Polygons
l A p Not rated or not available Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
n A/D Water Features line placement.The maps do not show the small areas of
Streams and Canals contrasting soils that could have been shown at a more detailed
n B scale.
Transportation
Q B/D
r4-1. Rails Please rely on the bar scale on each map sheet for map
n C measurements.
ti Interstate Highways
n CID US Routes Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
0 D Major Roads Coordinate System: Web Mercator(EPSG:3857)
n Not rated or not available Local Roads
Maps from the Web Soil Survey are based on the Web Mercator
Soil Rating Lines Background projection,which preserves direction and shape but distorts
• • A distance and area.A projection that preserves area,such as the
1111 Aerial Photography Albers equal-area conic projection,should be used if more
• • A/D accurate calculations of distance or area are required.
^r B This product is generated from the USDA-NRCS certified data as
.v B/D of the version date(s)listed below.
• r C Soil Survey Area: Union County, North Carolina
Survey Area Data: Version 22,Jan 21,2022
• • CID
Soil map units are labeled(as space allows)for map scales
• • D 1:50,000 or larger.
• w Not rated or not available Date(s)aerial images were photographed: Oct 28,2018—Oct
Soil Rating Points 30,2018
p A The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
O A/D imagery displayed on these maps.As a result,some minor
• B shifting of map unit boundaries may be evident.
• B/D
USDA Natural Resources Web Soil Survey 6/1/2022
Conservation Service National Cooperative Soil Survey Page 2 of 4

Hydrologic Soil Group—Union County, North Carolina Stonebow
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
BdB2 Badin channery silty C 0.0 0.9%
clay loam,2 to 8
percent slopes,
moderately eroded
GsB Goldston-Badin D 3.4 99.1%
complex,2 to 8
percent slopes
Totals for Area of Interest 3.4 100.0%
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 (ND, 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.
USDA Natural Resources Web Soil Survey 6/1/2022
Conservation Service National Cooperative Soil Survey Page 3 of 4

Hydrologic Soil Group—Union County, North Carolina Stonebow
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff.None Specified
Tie-break Rule: Higher
USDA Natural Resources Web Soil Survey 6/1/2022
Conservation Service National Cooperative Soil Survey Page 4 of 4

Flood Map:

National Flood Hazard Layer FIRMette : FEMA _Legend
80°42'2"W 35°1'19"N SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT
1 _ r
t WitthoZone At Base
Flood Elevation(BFE)
SPECIAL FLOOD With BFE or Depth Zone AE,AO,AH,VE,AR
' HAZARD AREAS Regulatory Floodway
1 • ,
_ • • \ 0.2%Annual Chance Flood Hazard,Areas
�--__� •• 4 of 1%annual chance flood with average
f .I • ra'l depth less than one foot or with drainage
! areas of less than one square mile zonex
•�•• LN'IDv COL TY r� r l , II�''I , Future Conditions 1%Annual
• _ Chance Flood Hazard zonex
• -� (ARPA NET INCiLLTDED) I , I ', %if I,- �" Area with Reduced Flood Risk due to
ps_. _ .
• l%' tII •' OTHER AREAS OF Levee.See Notes.zonex
I y 11,� �__ FLOOD HAZARD ��� Area with Flood Risk due to Leveezone D
NO SCREEN Area of Minimal Flood Hazard zone
r Effective LOMRs
111.• j- ,•5�,� OTHER AREAS Area of Undetermined Flood Hazard zone D
NI
GENERAL ----- Channel,Culvert,or Storm Sewer
STRUCTURES I I I I I I I Levee,Dike,or Floodwal
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111 1 . I1114_110.--- � 20.2 Cross Sections with 1%Annual Chance
tZ•s Water Surface Elevation
s' AREA OF MINIMAL'FLOOD HAZARD 8- - - Coastal Transect
• 4 ii ZX M s13 Base Flood Elevation Line(BFE)
Limit of Study
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li — Coastal Transect Baseline
IyProfile Baseline
II
w 3710449600J FEATURES Hydrographic Feature
Itiitic yS eff. 10/16/2008411
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`� e * r Digital Data Available N
• ' H
• I iii • 1F No Digital Data Available
el° • MAP PANELS Unmapped
r
is • { The pin displayed on the map is an approximate
III point selected by the user and does not represent
I '' �� an authoritative property location.
I
\EL•LAG' CV ..'ESIOE CHt, EL 410 i This map complies with FEMA's standards for the use of
, digital flood maps if it is not void as described below.
(e 1' W INCL EID) i The basemap shown complies with FEMA's basemap
I L • _,A accuracy standards
•' -- ` The flood hazard information is derived directly from the
•.•
authoritative NFHL web services provided by FEMA.This map
•• 4 was exported on 6/13/2022 at 1:52 PM and does not
I.___ '"•4003. reflect changes or amendments subsequent to this date and
time.The NFHL and effective information may change or
L
` become superseded by new data over time.
C, This map image is void if the one or more of the following map
\ ++f , •
I elements do not appear:basemap imagery,flood zone labels,
1 ! to F _ ._I legend,scale bar,map creation date,community identifiers,
80°41'24"W 35°0'S0"N FIRM panel number,and FIRM effective date.Map images for
Feet 1.6 00o unmapped and unmodernized areas cannot be used for
0 250 500 1,000 1,500 2,000 regulatory purposes.
Basemap:USGS National Map:Orthoimagery:Data refreshed October,2020

Drainage Area Maps:

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r/ / ! \ I / I / / / / / / / / 7 // / / / / / P2: 3.55 in arvDDESDry PRD.. 1016342
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/ / / / I 1 / / / QED: / / / / / / / 7 / T: 0.107 hr
/ / / / / / 1 / / / D �447 CON ! /\ / / / / / / / / / / / / ! NO. DESCRIPTION DATE
/ / / 7 \ / / / / / / / / 1 SKETCH PLAN 05.06.2022
/ / / B//ACK/SON 7 / / 1 / ! ! ! Shallow Concentrated Flow:
! / / /l lI I / / / l / // ! ! ,„,,/,/ / / / / / / / L: 222 ft 2 STORMWATER 12.16.2022
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/ / / / / / / / / / / / / / \ / / \ I / \_ V= 3.61 fps 5 LAND DEVELOPMENT 6.16.2023
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DESIGNED BY: CAP
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1 i I I / 1 1 I I I 4 I I I I / ( / / / / / / / / / / / / \ v LEGEND:
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/ EXIST.BOUNDARY LINE •• •■
\ \ /1 / I 1 1 1 I I I I \ \ \ \ I/ / — / / / / / / / / / \ \ EXIST.MINOR CONTOUR 552 — PRE DEVELOPMENT
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SHEET
NUMBER
EXHIBIT

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/ / \ / / m / / / / / I :fNGIN EEP:`�P�
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Z j/ / _ _ A TO BE TREATED BY 1,000 FT OF �� � %. .„,,,,---,
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/ / / / — — \ \` \_ ACRES - /y / SS 1 / ,1 I ` /// aEuw, as«o / �oi25noz3
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/ / / / / / ZONED Rio\ \ / i `
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/ / /
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/ �� � :7;7 i / / / / �^ \� ,S, / — / / / / MATiHEWS,NC 28104
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/ // / // / f� / / / / / / L"DDESION PRC' 1018342
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/ / / / _ REVISION/ISSUANCE
// // // I / / / O QED: < / / / / / / / / / / /
///''' / NO. DESCRIPTION DATE
/ / 1/ / / / / / / / / / I / / / I I 1 SKETCH PLAN 05.06.2022
ARDIA T
/ / / / // // / // / / B.7453. 447
z / / / / / / / / / / / / I 1 I / / 2 STORMWATER 12.18.2022
/ // / // / / // / / / / / / / / / / / / / ' / / / / / I I I 1 3 LAND DEVELOPMENT 1.11.2023
/ / / / / /// / \ / / / / / / / / / / /- / / / // \ 1 1 / / // // / \\ \\ \ \ \ \ -- 4 LAND DEVELOPMENT 3.31.2023
`L 5 LAND DEVELOPMENT 6.16.2023
/ / / / / 6 LAND DEVELOPMENT 8.11.2023
/ / / / / / / // I / / / / / \ \\ \\ \ \ 7 LAND DEVELOPMENT 9.8.2023
/ / / / // / /
/ / / /\\l I / / / /6y'` //i / / / \ \ ZONED.a-ao
arssa / / egK<R/ // \ 8 LAND DEVELOPMENT 10.3.2023
/ / / // / / / / / / /� / / / / / / // R�DaD o=T // / // \\ \� • �\ �\ /
9 LAND DEVELOPMENT 10.10.2023
� � \ 1 / / // // / // / / / / / \ / / / // // // \\ \ \ \\ \ � \__ / /
I / / / / / / I I l / �l I ' / wv \ LEGEND: DESIGNED BY: SB
\ I / / 1 / / I \ 1 / / / DRAWN BY: SB
— \ EXIST.BOUNDARY LINE ■■ ■■ CHECKED BY: FJM
/ 1 I \ I / / / \ / / / \ \ \ EXIST MAJOR CONTOUR 555 DALE NORTH
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PROP.MAJOR CONTOUR ---- 552 ---- ii
CD VERT: NIA
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\ I/ I I / I / / / / / / / / / / / / \ EXIST.PROPERTY LINE ---------- TITLE
\ \ I A/ / I I I I I I I I I \ \ \ / — — — J / / / / / / / / / / / \ \ \ DRAINAGE AREA LIMITS(SED.BASIN) _ SHEET POST DEVELOPMENT
\ / / I I I I� I I I \ \ V I / / / / / / / // / / V A UNDETAINED AREA HATCH P 7 DRAINAGE AREA MAP
�\ A�� / I /I I �� I I\ A \ V II �l / // / / //// ,/ ,/ / / // / \v \V OFFSITE DRAINAGE AREA HATCH LL � SHEET
NUMBER
EXHIBIT

Sediment Basin Calculations:

Sediment Basin Design
Project: Stonebow Computed By: DMG Date: 6/8/2022
Location: Union County,North Carolina Checked By: FJM Revised: 3/31/2023
Developer: Beulah Church Road Developers,LLC
Design Criteria: Settling Efficiency Criteria:
Design Storm 10 yr Design Storm 2 yr
Rational Runoff Coeff. 0.7 Rational Runoff Coeff. 0.6
Intensity 7.55 in/hr (Tc= 5 min.) Intensity 5.90 in/hr (Tc= 5 min.)
Max Bottom Top Surface Side- 10-yr
Basin Drainage Denuded Sediment Basin Area Depth Area Area slope Skimmer Orifice Dewatering Flow
Number Area (Acres) Area (Acres) Volume Sq ft ft. Sq ft Required Size Diameter Time cfs
Required Provided Sq ft (inches) (inches) (days)
SB (PH 1) 3.81 3.81 6,858 52,302 2,789 9 13,723 8,759 3 4.0 2.90 5.38 20.14
SB (PH 2) 3.69 3.69 6,642 52,302 2,789 9 13,723 8,483 3 4.0 2.90 5.38 19.50

SEDIMENT BASIN
Calculate Skimmer Size
Basin Volume in Cubic Feet 32,611 Cu.Ft Skimmer Size 4.0 Inch
Days to Drain* 3 Days Orifice Radius 1.5 Inch[es]
Orifice Diameter 2.9 Inch[es]
*In NC assume 3 days to drain

Temporary Slope Drain Calculations:

SB Slope Drain-1
Project Description
Friction Method Manning
Formula
Solve For Normal Depth
Input Data
Roughness Coefficient 0.024
Channel Slope 0.333 ft/ft
Diameter 10.0 in
Discharge 5.81 cfs
Results
Normal Depth 7.1 in
Flow Area 0.4 ft2
Wetted Perimeter 1.7 ft
Hydraulic Radius 3.0 in
Top Width 0.76 ft
Critical Depth 9.9 in
Percent Full 70.7%
Critical Slope 0.222 ft/ft
Velocity 14.09 ft/s
Velocity Head 3.08 ft
Specific Energy 3.67 ft
Froude Number 3.367
Maximum Discharge 7.37 cfs
Discharge Full 6.85 cfs
Slope Full 0.240 ft/ft
Flow Type Supercritical
GVF Input Data
Downstream Depth 0.0 in
Length 0.0 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.0 in
Profile Description N/A
Profile Headloss 0.00 ft
Average End Depth Over Rise 0.0 %
Normal Depth Over Rise 70.7%
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 7.1 in
Critical Depth 9.9 in
Channel Slope 0.333 ft/ft
Critical Slope 0.222 ft/ft
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
Sediment Basins Temp Pipes.fm8 Center [10.03.00.03]
6/13/2022 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

SB Slope Drain-2
Project Description
Friction Method Manning
Formula
Solve For Normal Depth
Input Data
Roughness Coefficient 0.024
Channel Slope 0.333 ft/ft
Diameter 15.0 in
Discharge 11.15 cfs
Results
Normal Depth 8.0 in
Flow Area 0.7 ft2
Wetted Perimeter 2.0 ft
Hydraulic Radius 3.9 in
Top Width 1.25 ft
Critical Depth 14.5 in
Percent Full 53.1 %
Critical Slope 0.089 ft/ft
Velocity 16.86 ft/s
Velocity Head 4.42 ft
Specific Energy 5.08 ft
Froude Number 4.084
Maximum Discharge 21.72 cfs
Discharge Full 20.19 cfs
Slope Full 0.102 ft/ft
Flow Type Supercritical
GVF Input Data
Downstream Depth 0.0 in
Length 0.0 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.0 in
Profile Description N/A
Profile Headloss 0.00 ft
Average End Depth Over Rise 0.0 %
Normal Depth Over Rise 53.1 %
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 8.0 in
Critical Depth 14.5 in
Channel Slope 0.333 ft/ft
Critical Slope 0.089 ft/ft
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
Sediment Basins Temp Pipes.fm8 Center [10.03.00.03]
6/13/2022 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

Temporary Diversion Ditch Calculations:

DITCH 1
Project Description
Friction Method Manning
Formula
Solve For Normal Depth
Input Data
Roughness Coefficient 0.020
Channel Slope 0.055 ft/ft
Left Side Slope 3.000 H:V
Right Side Slope 3.000 H:V
Bottom Width 2.00 ft
Discharge 5.81 cfs
Results
Normal Depth 3.7 in
Flow Area 0.9 ft2
Wetted Perimeter 3.9 ft
Hydraulic Radius 2.7 in
Top Width 3.84 ft
Critical Depth 6.0 in
Critical Slope 0.009 ft/ft
Velocity 6.49 ft/s
Velocity Head 0.65 ft
Specific Energy 0.96 ft
Froude Number 2.368
Flow Type Supercritical
GVF Input Data
Downstream Depth 0.0 in
Length 0.0 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.0 in
Profile Description N/A
Profile Headloss 0.00 ft
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 3.7 in
Critical Depth 6.0 in
Channel Slope 0.055 ft/ft
Critical Slope 0.009 ft/ft
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
Drainage Ditch Calcs.fm8 Center [10.03.00.03]
6/13/2022 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

6/13/22,3:39 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Ditch 1
Name Ditch 1
Discharge 5.81
Channel Slope 0.055
Channel Bottom Width 2
Left Side Slope 3
Right Side Slope 3
Low Flow Liner
Retardence Class C 6-12 in
Vegetation Type Mix(Sod and Bunch)
Vegetation Density Good 65-79%
Soil Type Clay Loam(CL)
C125
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
C125 Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 2.3 lbs/ft2 1.05 lbs/ft2 2.19 STABLE D
Unvegetated
Underlying Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 2.51 lbs/ft2 0.78 Ibs/ft2 3.22 STABLE D
Substrate
SC150
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
SC150 Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 2 lbs/ft2 1.05 Ibs/ft2 1.9 STABLE D
Unvegetated
Underlying Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 2.18 lbs/ft2 0.78 lbs/ft2 2.8 STABLE D
Substrate
S150
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
S150 Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.8 lbs/ft2 1.05 lbs/ft2 1.71 STABLE D
Unvegetated
Underlying Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.96 Ibs/ft2 0.78 Ibs/ft2 2.52 STABLE D
Substrate
DS150
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
DS150 Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.8 Ibs/ft2 1.05 Ibs/ft2 1.71 STABLE D
Unvegetated
Underlying Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.96 lbs/ft2 0.78 lbs/ft2 2.52 STABLE D
Substrate
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
S75 Unvegetated Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.6 lbs/ft2 1.05 lbs/ft2 1.52 STABLE D
https://ecmds.com/project/152587/channel-analysis/225949/show 1/2

6/13/22,3:39 PM ECMDS 7.0
Underlying Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.74 lbs/ft2 0.78 lbs/ft2 2.24 STABLE D
Substrate
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 4 lbs/ft2 1.05 lbs/ft2 3.81 STABLE --
Vegetation
Underlying Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 0.75 lbs/ft2 0.78 lbs/ft2 0.96 UNSTABLE --
Substrate
DS75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
DS75 Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.6 lbs/ft2 1.05 lbs/ft2 1.52 STABLE D
Unvegetated
Underlying Straight 5.81 cfs 6.48 ft/s 0.31 ft 0.02 1.74 lbs/ft2 0.78 lbs/ft2 2.24 STABLE D
Substrate
https://ecmds.com/project/152587/channel-analysis/225949/show 2/2

DITCH 2
Project Description
Friction Method Manning
Formula
Solve For Normal Depth
Input Data
Roughness Coefficient 0.020
Channel Slope 0.055 ft/ft
Left Side Slope 3.000 H:V
Right Side Slope 3.000 H:V
Bottom Width 2.00 ft
Discharge 11.79 cfs
Results
Normal Depth 5.3 in
Flow Area 1.5 ft2
Wetted Perimeter 4.8 ft
Hydraulic Radius 3.7 in
Top Width 4.67 ft
Critical Depth 8.7 in
Critical Slope 0.008 ft/ft
Velocity 7.94 ft/s
Velocity Head 0.98 ft
Specific Energy 1.43 ft
Froude Number 2.484
Flow Type Supercritical
GVF Input Data
Downstream Depth 0.0 in
Length 0.0 ft
Number Of Steps 0
GVF Output Data
Upstream Depth 0.0 in
Profile Description N/A
Profile Headloss 0.00 ft
Downstream Velocity Infinity ft/s
Upstream Velocity Infinity ft/s
Normal Depth 5.3 in
Critical Depth 8.7 in
Channel Slope 0.055 ft/ft
Critical Slope 0.008 ft/ft
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
Drainage Ditch Calcs.fm8 Center [10.03.00.03]
6/13/2022 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

6/13/22,3:40 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Ditch 2
Name Ditch 2
Discharge 11.79
Channel Slope 0.055
Channel Bottom Width 2
Left Side Slope 3
Right Side Slope 3
Low Flow Liner
Retardence Class C 6-12 in
Vegetation Type Mix(Sod and Bunch)
Vegetation Density Good 65-79%
Soil Type Clay Loam(CL)
C125
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
C125 Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 2.3 lbs/ft2 1.53 lbs/ft2 1.51 STABLE D
Unvegetated
Underlying Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 2.51 lbs/ft2 1.06 lbs/ft2 2.37 STABLE D
Substrate
SC150
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
SC150 Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 2 lbs/ft2 1.53 Ibs/ft2 1.31 STABLE D
Unvegetated
Underlying Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 2.18 lbs/ft2 1.06 lbs/ft2 2.06 STABLE D
Substrate
S150
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
S150 Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.8 lbs/ft2 1.53 lbs/ft2 1.18 STABLE D
Unvegetated
Underlying Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.96 Ibs/ft2 1.06 Ibs/ft2 1.86 STABLE D
Substrate
DS150
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
DS150 Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.8 Ibs/ft2 1.53 Ibs/ft2 1.18 STABLE D
Unvegetated
Underlying Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.96 lbs/ft2 1.06 lbs/ft2 1.86 STABLE D
Substrate
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
S75 Unvegetated Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.6 lbs/ft2 1.53 lbs/ft2 1.05 STABLE D
https://ecmds.com/project/152587/channel-analysis/225951/show 1/2

6/13/22,3:40 PM ECMDS 7.0
Underlying Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.74 lbs/ft2 1.06 lbs/ft2 1.65 STABLE D
Substrate
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 4 lbs/ft2 1.53 lbs/ft2 2.62 STABLE --
Vegetation
Underlying Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 0.75 lbs/ft2 1.06 lbs/ft2 0.71 UNSTABLE --
Substrate
DS75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
DS75 Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.6 lbs/ft2 1.53 lbs/ft2 1.05 STABLE D
Unvegetated
Underlying Straight 11.79 cfs 7.95 ft/s 0.44 ft 0.02 1.74 lbs/ft2 1.06 lbs/ft2 1.65 STABLE D
Substrate
https://ecmds.com/project/152587/channel-analysis/225951/show 2/2

Pre Development Calculations:

PRE _ DEv
SubCat Reach 'on• MI Routing Diagram for 1018342 Stonebow_BMP WETPOND_5.25.23
Prepared by{enter your company name here), Printed 6/12/2023
HydroCAD®10.10-4a s/n 09780 ©2020 HydroCAD Software Solutions LLC

1018342 Stonebow_BMP WETPOND_6.16.23 Type II 24-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 6/15/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1S: PRE-DEV
Runoff = 18.79 cfs @ 12.00 hrs, Volume= 0.972 af, Depth= 2.87"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-yr Rainfall=5.18"
Area (ac) CN Description
* 4.070 78
4.070 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
8.3 Direct Entry,
Subcatchment 1 S: PRE-DEV
Hydrograph
- T - T - 1- -I - 7 - - -I- -I - T - I- - 1 1 - -I - T - T -I- -
21_ T 1 7 - T I 1 1 1 T I ■Runoff
204z 1 118.79 cfs I I 1 1 1 1 1 1 1 1 1 1 1 1 1 r 1 1
19 —
18 1 I 1 1 I 1 1 I I 1 I ITXpe 1�11 2441r
174 — -1- 1 1 I I I I I I I tp= illairitati- y
164 I I I I I I I I I I I I ��J 7r /ICI w1I1n�,n
15 ,- I L - 1- 1 J L 1 J L 1 _Runoff Atea=4;0-70 ale -
144-/ I L - I I H 1_ I_ _I L 1 I H H - I- -I H - H I -
13 _ -1- - I- -I - - 1- -I- -I - 4- -RunoffVolu-me=0.972af
w 12� L II - H -II ��p��n
11� __ 1 1 _ t_ _1_ H f 1 ��nYH ID�Rt =4.OJI -
0 10; -I- - -I - rt - r -I- - fi - I- -I - rt - - I- J-
I -I - - T =B r miIn
I - � - � -I- � - T - I- -I - � - T - I- -I - T - 7�-�Ip -
8 1 T T -1- T T I T T I I -FCN=/lv
7 -/ —
6 I I 1 1 I I I I I I II -
5 - -1 _ 1 1 I I 1 1 I I I I I I II -
44,/ I I I I I I I I I I I I I I I I
3� -I- 1 1 1 1 1 1 1 1 1 1 I_
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND_6.16.23 Type II 24-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 6/15/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1S: PRE-DEV
Runoff = 24.33 cfs @ 12.00 hrs, Volume= 1.268 af, Depth= 3.74"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-yr Rainfall=6.18"
Area (ac) CN Description
* 4.070 78
4.070 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
8.3 Direct Entry,
Subcatchment 1 S: PRE-DEV
Hydrograph
1 1 I 1 I I I I I I I I I I I I I
26� I I I I I I I I I I I I I I I ■Runoff
,I- 1 1 24.33 cfs I k - 1- - 4 i- 1 - -k - I- 1 A - - 1 1 4 1 1 -
24 ' 1 1 1 I I I I 1 1 1 IType 11II 24-hr
22774- 11 - 'I- - t t -I t 11 �Y Yg u—Nra o=`f' "
20 ' 1 1 I I I I I -Rutleff Aker=407O-ac -
187" 1 1 1 I I I I I I I I I I I I I
T 1 1 -r 1- 1 - 1- Runoff-Volum-e=436-8-af -
Iii
16_ -1- L - 1- _I - 1 - L - 1- _1 _ L - I- _1 nl.ic 1DpI
14� 1 1 1 1 1 1 Q 1 p 11
o I I I I
Li12� Tc=8.3 m i n
,_ 1 -k 1 4 -k 1 4 1- 1 1 4 1- �1 p
10� 1 1 1 I 1 I I I I I I CAI=78
8� T I 1 I I 1 1 I I I I I 1 1 1
4- -I t 11 - 1- - I- - - I 1 -
6 -' _ _
4.::-' I +4 1 1 1 1 1 1 1 I
1- 1 I - 1
o=11 / �iiii�i�ii , , /hill/ iiiiiiiiiii 1�1�����//P
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

< 2S 1 1S
POS —DEV UNDE AINED
5 P
WETPON
II
12L
DISCHARGE
(Subca Reach on. MI Routing Diagram for 1018342 Stonebow_BMP WETPOND
Prepared by LandDesign Inc, Printed 10/25/2023
HydroCAD®10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC

1018342 Stonebow_BMP WETPOND Type 1124-hr 10-yr Rainfall=5.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 2S: POST-DEV
Runoff = 20.52 cfs @ 11.95 hrs, Volume= 0.969 af, Depth= 3.24"
Routed to Pond 5P : WETPOND
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-yr Rainfall=5.18"
Area (ac) CN Description
* 1.520 61 GRASS
2.070 98 Paved roads w/curbs & sewers, HSG A
3.590 82 Weighted Average
1.520 42.34% Pervious Area
2.070 57.66% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 107 0.36 Direct Entry, DIRECT
Subcatchment 2S: POST-DEV
Hydrograph
A — - - ■Runoff
22= 20.52 cfs I
20
19
1a L H H H H H rt 1-y iir�fall .1I" _
17 H- H I I —I RurtoffAted=3L5910 �Ic =
16�
15
14?/ o Vfo14 P9• 9 f
12/ n f " -
'Flow -
10= — CEn�iI1
9 � I I —I —I 4 II _� I 4
$� =
54/— -
41/—
3_/ I/
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 10-yr Rainfall=5.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 11S: UNDETAINED
Runoff = 2.17 cfs @ 11.96 hrs, Volume= 0.100 af, Depth= 2.51"
Routed to Link 12L : DISCHARGE
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-yr Rainfall=5.18"
Area (ac) CN Description
0.480 74 >75% Grass cover, Good, HSG C
0.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 11S: UNDETAINED
Hydrograph
0 Runoff
2.17 cfs
Tyie-II-4-hr -
2 / 16-yll- Rainfall=5.18"
Runoff Area=0L480 ac
Runoff Volume=9.100 af
R'unpff Depth=2.51"
o -
LL / —Tc— .0-m its -
61= 4
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 11 24-hr 10-yr Rainfall=5.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 4
Summary for Pond 5P: WETPOND
Inflow Area = 3.590 ac, 57.66% Impervious, Inflow Depth = 3.24" for 10-yr event
Inflow = 20.52 cfs @ 11.95 hrs, Volume= 0.969 af
Outflow = 2.78 cfs @ 12.20 hrs, Volume= 0.963 af, Atten= 86%, Lag= 15.0 min
Primary = 2.78 cfs @ 12.20 hrs, Volume= 0.963 af
Routed to Link 12L : DISCHARGE
Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Peak Elev= 631.38' @ 12.20 hrs Surf.Area= 0.236 ac Storage= 0.474 af
Plug-Flow detention time= 460.3 min calculated for 0.962 af(99% of inflow)
Center-of-Mass det. time= 458.1 min ( 1,268.9 - 810.8 )
Volume Invert Avail.Storage Storage Description
#1 629.00' 1.110 af Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
629.00 0.154 0.000 0.000
629.50 0.179 0.083 0.083
630.00 0.195 0.093 0.177
631.00 0.225 0.210 0.387
632.00 0.253 0.239 0.626
633.00 0.283 0.268 0.894
634.00 0.150 0.216 1.110
Device Routing Invert Outlet Devices
#1 Primary 626.78' 15.0" Round Culvert
L= 87.0' RCP, square edge headwall, Ke= 0.500
Inlet/Outlet Invert= 626.78' / 626.11' S= 0.0077 '/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 630.00' 24.0" W x 3.0" H Vert. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#3 Device 1 629.00' 1.5" Vert. Orifice/Grate -WQ C= 0.600
Limited to weir flow at low heads
#4 Device 1 632.00' 48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600 in 48.0" x 48.0" Grate (100°/0 open area)
Primary OutFlow Max=2.78 cfs @ 12.20 hrs HW=631.38' (Free Discharge)
-1=Culvert (Passes 2.78 cfs of 10.51 cfs potential flow)
-2=Orifice/Grate (Orifice Controls 2.69 cfs @ 5.39 fps)
-3=Orifice/Grate -WQ (Orifice Controls 0.09 cfs @ 7.33 fps)
-4=Orifice/Grate ( Controls 0.00 cfs)

1018342 Stonebow_BMP WETPOND Type 1124-hr 10-yr Rainfall=5.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 5
Pond 5P: WETPOND
Hydrograph
— - - ❑ Inflow
;/ 20.52 cfs - ❑Primary
221 Inflow-Ari --�' . 9d-abC
20Y I- ek C1.�661 361-
19 �
187
17 / I 4 H H H H iota e40.47 f-
16
15 /
14V
13
c 11_
44/ 2.78 cfs
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 11 24-hr 10-yr Rainfall=5.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 6
Summary for Link 12L: DISCHARGE
Inflow Area = 4.070 ac, 50.86% Impervious, Inflow Depth > 3.13" for 10-yr event
Inflow = 4.37 cfs @ 11.99 hrs, Volume= 1.063 af
Primary = 4.37 cfs @ 11.99 hrs, Volume= 1.063 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Link 12L: DISCHARGE
Hydrograph
/ d 47 rf ❑Inflow
❑Primary
4.37 cfs Inflow Area=4.070 ac
4-
3-
o• _
LL 2-
1-
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 2S: POST-DEV
Runoff = 25.99 cfs @ 11.95 hrs, Volume= 1.242 af, Depth= 4.15"
Routed to Pond 5P : WETPOND
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-yr Rainfall=6.18"
Area (ac) CN Description
* 1.520 61 GRASS
2.070 98 Paved roads w/curbs & sewers, HSG A
3.590 82 Weighted Average
1.520 42.34% Pervious Area
2.070 57.66% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 107 0.36 Direct Entry, DIRECT
Subcatchment 2S: POST-DEV
Hydrograph
— 4 -
26/d 25.99 cfs ❑Runoff
Ty lll4lr -
24,
22- / 12 -y�r Rainfall=G.1 "
20- Run-off Area=3L590 ac
18- Runoff V4olume=1.242 af
16 Runoff Depth=4.15" -
14-
- -Flow Leng h 107'
LL 12
10- 1-c= m i n
$_/ I CN=82
z= [ _
0= !(
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment 11S: UNDETAINED
Runoff = 2.87 cfs @ 11.96 hrs, Volume= 0.133 af, Depth= 3.34"
Routed to Link 12L : DISCHARGE
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-yr Rainfall=6.18"
Area (ac) CN Description
0.480 74 >75% Grass cover, Good, HSG C
0.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 11S: UNDETAINED
Hydrograph
_/
❑Runoff
31 2.87 cfs
Tye II 24-hr
2 -ylr Rainfall=6.18"
Runoff Areal=0L480 ac
2- Iuiofjf Volum!=9.1 33 af
R'unpff Depth=3.34"
u_
Tc= .0 m i n
C1=7L4
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 9
Summary for Pond 5P: WETPOND
Inflow Area = 3.590 ac, 57.66% Impervious, Inflow Depth = 4.15" for 25-yr event
Inflow = 25.99 cfs @ 11.95 hrs, Volume= 1.242 af
Outflow = 3.37 cfs @ 12.22 hrs, Volume= 1.236 af, Atten= 87%, Lag= 15.7 min
Primary = 3.37 cfs @ 12.22 hrs, Volume= 1.236 af
Routed to Link 12L : DISCHARGE
Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Peak Elev= 631.97' @ 12.22 hrs Surf.Area= 0.252 ac Storage= 0.618 af
Plug-Flow detention time= 386.0 min calculated for 1.236 af(99% of inflow)
Center-of-Mass det. time= 382.6 min ( 1,186.4 - 803.8 )
Volume Invert Avail.Storage Storage Description
#1 629.00' 1.110 af Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
629.00 0.154 0.000 0.000
629.50 0.179 0.083 0.083
630.00 0.195 0.093 0.177
631.00 0.225 0.210 0.387
632.00 0.253 0.239 0.626
633.00 0.283 0.268 0.894
634.00 0.150 0.216 1.110
Device Routing Invert Outlet Devices
#1 Primary 626.78' 15.0" Round Culvert
L= 87.0' RCP, square edge headwall, Ke= 0.500
Inlet/Outlet Invert= 626.78' / 626.11' S= 0.0077 '/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 630.00' 24.0" W x 3.0" H Vert. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#3 Device 1 629.00' 1.5" Vert. Orifice/Grate -WQ C= 0.600
Limited to weir flow at low heads
#4 Device 1 632.00' 48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600 in 48.0" x 48.0" Grate (100°/0 open area)
Primary OutFlow Max=3.37 cfs @ 12.22 hrs HW=631.97' (Free Discharge)
-1=Culvert (Passes 3.37 cfs of 11.25 cfs potential flow)
-2=Orifice/Grate (Orifice Controls 3.27 cfs @ 6.54 fps)
-3=Orifice/Grate -WQ (Orifice Controls 0.10 cfs @ 8.21 fps)
-4=Orifice/Grate ( Controls 0.00 cfs)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 10
Pond 5P: WETPOND
Hydrograph
_ I— —1 0 Inflow
28-v 25.99 cfs ❑Primary
I flow-Area--�' . d-aC
26�
24 /— 4 4 1- e -k Bbv-6 1 .9
� /
20 I I I -Siorage=0.t-1$-ally
18/ ' t 1-
16� t 1
0 14i / L
LI12_ - fi 1 H fi fi
10=
8 .--/ /4— tI H 4 L
6/ f -I 7 1- I- - T -T -
4 / , 3.37 cfs — — — — — —
2
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by LandDesign Inc Printed 10/25/2023
HydroCAD® 10.20-3c s/n 09780 ©2023 HydroCAD Software Solutions LLC Page 11
Summary for Link 12L: DISCHARGE
Inflow Area = 4.070 ac, 50.86% Impervious, Inflow Depth > 4.04" for 25-yr event
Inflow = 5.63 cfs @ 11.98 hrs, Volume= 1.369 af
Primary = 5.63 cfs @ 11.98 hrs, Volume= 1.369 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Link 12L: DISCHARGE
Hydrograph
I ri F� rf ❑Inflow
6� 5 ❑Primary
.63 cfs
y Infl w Area=4.07 ac
5:/
4
0 3
2
17
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Water Quality Calculations:

<1OS <14S>
POST—DE (MOD C) UND -TAINED
9 P
WETPOND
lir
15L
DISCHARGE
(Subca Reach 'on• MP Routing Diagram for 1018342 StonebowBMP WETPOND
Prepared by{enter your company name here),_Printed 7/18/2023
HydroCAD®10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC

1018342 Stonebow_BMP WETPOND Type 1124-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 10S: POST-DEV (MOD C)
Runoff = 26.90 cfs @ 11.95 hrs, Volume= 1.550 af, Depth= 5.18"
Routed to Pond 9P : WETPOND
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-yr Rainfall=5.18"
Area (ac) CN Description
* 3.590 100 PAVED PARKING
3.590 100.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 107 0.36 Direct Entry, DIRECT
Subcatchment 10S: POST-DEV (MOD C)
Hydrograph
7 T I- 1 - - I- - I- -I T - I- 1 - 7 - r - I- -I 7 I 1
30_ -I 4 I- 1 - T 1 4 4- 1 I 4 - 1 ■Runoff
284/ 1 126.90 cfs I I I I I 1 I 1 1 I 1 1 I
26 1 I I I I 1 I 1 1Typei1 r 244r -
24
22 - I I I I -Rutheff A l=3590�E -
18 1 - 11 1 I Runoff Orume=1-.550 I
-
L 1 _I 4 1 Runoff 11Dppth= .10"
z16: 1
_0 14� F�bw ILe gth- 1 Oru 12 T 1 II I I I I I I I
- - - T - I -1 - 7 - 7 - I-TIC=5�rmin
10�
4- -1- ' -1 - -+ - i- - I- -I -ON- 100
8� 1 I I I I I 1
6 -/ I I I
4
o� ii ioiiiiiiiiiii ii�i� ice//
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 14S: UNDETAINED
Runoff = 2.17 cfs @ 11.96 hrs, Volume= 0.100 af, Depth= 2.51"
Routed to Link 15L : DISCHARGE
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-yr Rainfall=5.18"
Area (ac) CN Description
0.480 74 >75% Grass cover, Good, HSG C
0.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 14S: UNDETAINED
Hydrograph
1 I 1 1 I I 1 1 1 1 I I 1 1 I 1 1 I
I 1 1 I I 1 1 I I I I I I 1 1 ■Runoff
2. cfs 1 I I 1 1 I I I I I
J_ »—I — _L — I— —I — — I_ —I — -i — _L _ I_ Type1l-24-hr
21 1 / 1 I 1 1 '1 1O-yr Rainfall,I=$.18"
I Runoff Area=O'.48110 ac
I I
1 1 Runoff Vlolume=0.100 af
1 I Rjunpff,Depth= .51
o _I_ / . L _ I— — 1 — I— —I - fL_=5.O' min-
`� 1-( 1 1 1 1 1 I 1 1
1 1 1 1 1 CAI=74
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type II 24-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 4
Summary for Pond 9P: WETPOND
Inflow Area = 3.590 ac,100.00% Impervious, Inflow Depth = 5.18" for 10-yr event
Inflow = 26.90 cfs @ 11.95 hrs, Volume= 1.550 af
Outflow = 9.32 cfs @ 12.07 hrs, Volume= 1.550 af, Atten= 65%, Lag= 7.3 min
Primary = 9.32 cfs @ 12.07 hrs, Volume= 1.550 af
Routed to Link 15L : DISCHARGE
Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Peak Elev= 630.52'@ 12.07 hrs Surf.Area= 0.211 ac Storage= 0.283 af
Plug-Flow detention time=(not calculated: outflow precedes inflow)
Center-of-Mass det. time= 5.8 min ( 726.0 - 720.1 )
Volume Invert Avail.Storage Storage Description
#1 629.00' 1.110 af Custom Stage Data (Prismatic)Listed below(Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
629.00 0.154 0.000 0.000
629.50 0.179 0.083 0.083
630.00 0.195 0.093 0.177
631.00 0.225 0.210 0.387
632.00 0.253 0.239 0.626
633.00 0.283 0.268 0.894
634.00 0.150 0.216 1.110
Device Routing Invert Outlet Devices
#1 Primary 626.78' 15.0" Round Culvert
L= 87.0' RCP, square edge headwall, Ke= 0.500
Inlet/ Outlet Invert= 626.78'/626.11' S= 0.0077 '/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 629.00' 1.5" Horiz. Orifice/Grate -WQ C= 0.600
Limited to weir flow at low heads
#3 Device 1 630.00' 2.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
0.5' Crest Height
#4 Device 1 629.00' 48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Primary OutFlow Max=9.29 cfs @ 12.07 hrs HW=630.50' (Free Discharge)
L1=Culvert (Barrel Controls 9.29 cfs @ 7.57 fps)
2=Orifice/Grate -WQ (Passes < 0.07 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 2.48 cfs potential flow)
4=Orifice/Grate (Passes < 94.43 cfs potential flow)

1018342 Stonebow_BMP WETPOND Type 1124-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 5
Pond 9P: WETPOND
Hydrograph
I 1 1 T 1 T 1 I T I
30_ /- 1 -1 I -1 1 1 T T T I I T I 1 — T — —I - ❑ Inflow
1126.90cfs 11 1 1 1 1 1 1 1 1 1 1 1 1 1 ❑Primary
28;:-/_ i I I I I I_ InflowArea=3.5gO ac
I I I I
24� z- 1- - 7 - 1- -1 e 1 T T I T raKTGIIeVV40U1 u
/ k -1- I- -I - 4 - 1- -1 - + - I- -I - + - - - - + - I-
-I -I
22= , _1_ 1 1 I 1 1 I 1 S orage-r . 8 of _
20� , �
18- 1 I I 1 1 I I 1 1 I I I I I
i
"C), 16� 1 I I 1 1 I I 1 1 I I I I I
- /
0 14 A- -1- I- -I - -F - 1- -1 - - I- -I - t - I- -I - t - I- -1 - t - 1- -I -
LL ' I 1 _L - I- -I T I I - T - -1 T 1- -I - T - I _I
12� ,
1 9.32 cfs -
10_ , / 1 I I 1 1 I I 1
8 -/ /- 1 I I I I I I
6y fi O t - - - - - - - t
E
y � � T H - T
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type II 24-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 6
Summary for Link 15L: DISCHARGE
Inflow Area = 4.070 ac, 88.21% Impervious, Inflow Depth = 4.86" for 10-yr event
Inflow = 10.99 cfs @ 11.99 hrs, Volume= 1.650 af
Primary = 10.99 cfs @ 11.99 hrs, Volume= 1.650 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Link 15L: DISCHARGE
Hydrograph
1 1 1 1 1 L 1
I
1 I I I 1 1 1 ■Inflow 1
12- /- 110.99 cfs f l IA I IT T I T 1 IA I I 1 - U Primary
10.99as
11 —1 — 1 - I- -I 1 _ I- -Inflow-Area=4.Q7_0_ c- -
- / e I I I I I I I I I I I I I I I I
10= 1 7 I I T - T T 1 T I i
8- /- - j�� 1 J I 1 T T T 1 T
= i I I I I I 1 1 I
3 6_' /— 1 rt 1— 1 T 1 — T 1 T - -
o -
IT - 1 1 1 1 1 1 1 1
5-'
- i I I I I 1 1 1 1
4 /— 1 rt 1 1 J
1 T 1 T I - -
3- -
1 1 1 1 1 1 1 I I
1111 1 1 1 1 1
2 � rt I I rt 1 T 1 I T I - -
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 10S: POST-DEV (MOD C)
Runoff = 32.09 cfs @ 11.95 hrs, Volume= 1.849 af, Depth= 6.18"
Routed to Pond 9P : WETPOND
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-yr Rainfall=6.18"
Area (ac) CN Description
* 3.590 100 PAVED PARKING
3.590 100.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 107 0.36 Direct Entry, DIRECT
Subcatchment 10S: POST-DEV (MOD C)
Hydrograph
I I I I I I I
1 — T T ■Runoff
34� 13209 cfs I I - rt - fi — 1-
-I — rt - 11 -1- —
32� k I — t — 1— —1 — —[ — t — 17 ype-I1-24-hr —
30: I — - — I- -I - - -. - ��
28� 1- 1245-Y�r /I airrfiaiI � �1_o —
26 , —1— _ 1 — L —I— —I — 1 — 1— uti of Are�1= 590-de —
244/ 1— — L 1 J L 1 1 I L 1 I 1 L 1
22 , 1 - I I I I I Runoof�VoIsumpe�=}1�.849 of
20/ , —1— I I 1 I I 1 '�M"Qfl 11D"IM"'I'* „ —
18
LL 16y 1 FJow 1Lehgt 1 or _
14� 1 ii 1 1 1 1 1 1 1 1 1
I 1 I 1 1 TIIc=-5-O Ir ni n -
124-/
10� � — T — 1— —1 — 7 — T — 1— —1 —O N- 1=ln —
� 1 - rt - '7 — I- -I — I—
8 �
_ / ' — t - 1 -1- —
6y
4 / T 1 1 1
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment 14S: UNDETAINED
Runoff = 2.87 cfs @ 11.96 hrs, Volume= 0.133 af, Depth= 3.34"
Routed to Link 15L : DISCHARGE
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-yr Rainfall=6.18"
Area (ac) CN Description
0.480 74 >75% Grass cover, Good, HSG C
0.480 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 14S: UNDETAINED
Hydrograph
1 1 1I I1 I 1 1 I I 1 1 I 1 1
I I 1 1 I 1 1 — I— CI Runoff
3 zs�cfs 1 1 1 1 1 I I I I I 1 1
1 1 1 1 1 I I I I I 1 Type 1II 24-hr
I11 11 II201
-yr F ainfall,l=0.18"
_ I I ' Runoff Area=O'.480 ac
— —I — — - I- -I - — I— 1 1 —1-
2—/ 1 1 I Runoff Vlolume=0.133 af
y Rjunoff,Dept6=$.34"
1 1 Tc=5.0' min
I1N
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type II 24-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 9
Summary for Pond 9P: WETPOND
Inflow Area = 3.590 ac,100.00°/o Impervious, Inflow Depth = 6.18" for 25-yr event
Inflow = 32.09 cfs @ 11.95 hrs, Volume= 1.849 af
Outflow = 9.92 cfs @ 12.08 hrs, Volume= 1.849 af, Atten= 69%, Lag= 7.9 min
Primary = 9.92 cfs @ 12.08 hrs, Volume= 1.849 af
Routed to Link 15L : DISCHARGE
Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Peak Elev= 630.94'@ 12.08 hrs Surf.Area= 0.223 ac Storage= 0.374 af
Plug-Flow detention time=7.6 min calculated for 1.848 af(100% of inflow)
Center-of-Mass det. time= 7.6 min ( 727.8 - 720.1 )
Volume Invert Avail.Storage Storage Description
#1 629.00' 1.110 af Custom Stage Data (Prismatic)Listed below(Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
629.00 0.154 0.000 0.000
629.50 0.179 0.083 0.083
630.00 0.195 0.093 0.177
631.00 0.225 0.210 0.387
632.00 0.253 0.239 0.626
633.00 0.283 0.268 0.894
634.00 0.150 0.216 1.110
Device Routing Invert Outlet Devices
#1 Primary 626.78' 15.0" Round Culvert
L= 87.0' RCP, square edge headwall, Ke= 0.500
Inlet/ Outlet Invert= 626.78'/626.11' S= 0.0077 '/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 629.00' 1.5" Horiz. Orifice/Grate -WQ C= 0.600
Limited to weir flow at low heads
#3 Device 1 630.00' 2.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
0.5' Crest Height
#4 Device 1 629.00' 48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600 in 48.0" x 48.0" Grate (100% open area)
Primary OutFlow Max=9.91 cfs @ 12.08 hrs HW=630.93' (Free Discharge)
L1=Culvert (Barrel Controls 9.91 cfs @ 8.07 fps)
2=Orifice/Grate -WQ (Passes < 0.08 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 6.55 cfs potential flow)
4=Orifice/Grate (Passes < 107.08 cfs potential flow)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 10
Pond 9P: WETPOND
Hydrograph
I 1 1 - 1 1 I I 1 I
17 -I- 7 - I- -I - 7 - I- -I - T - T -I - T - I- -I - T - I- -I - T - I- -I - ❑ Inflow
/ /- 1132.09 I- 1 rt i- I T I- I T I I /�T.� I 1 CT I T 0 Primary
34� , I1fIow Al ea=3-.J90-a�i
32i-/ ,
- rt - 1- -1 - -r - 1- -1 - t -11 -. -r 1- -11 -.+rt�/-..1-
30 , � 1- -1 - -r - 1- -1 - -r - 1 -1 - t - e-a-KrUelt=3�1.9
28 ,7 -1 HI I 1 126 , - - 1- 1 - H- - - + - H 1 - + - I.
0rage O.
247-! ,
- - 1- -14H1 + H1 + 11 + 1I + I1
22
I- -1 - 4 - I- -I - 4 - I- -1 - + - I- -1 - + - I- -1 - + - I- -1
0 20� ,
318- , z- I_ _1 - -L - I- -I - H - I_ _1 - H - I- -1 - H - I- -1 - H - 1- -1
`L 16 , 1 I _1 H 1 _1 I I + 1 I + I I + 1 -I
14 -/ , I 1 I_ I 1 I I 1 I I 1 I I H I _II -
12; / _ 9.92cfs — _I - 1 - L -I - L - L -I - 1 - I- -I - L - I- -I - 1 - I- L
10� / % I— —I — 1 - L _I - L - L _I - 1 - 1_ _I - I - I_ _I - I - 1_ L _
8/ i z— 711' 1 1 I I I 1 1 1 I I 1 1 1 I I I 1
6� , _� 1 1 1 I I I I I 1 1
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_BMP WETPOND Type 1124-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 7/18/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 11
Summary for Link 15L: DISCHARGE
Inflow Area = 4.070 ac, 88.21% Impervious, Inflow Depth = 5.84" for 25-yr event
Inflow = 12.16 cfs @ 11.99 hrs, Volume= 1.982 af
Primary = 12.16 cfs @ 11.99 hrs, Volume= 1.982 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Link 15L: DISCHARGE
Hydrograph
I I 1 I I I I I I I I
■Inflow `
131„, A_ _ 112.1Bds I_ I— —1 + — I— + 1 1 +r— 1 1 A+7 1 + - ❑Primary
12 / I121�ts InfIowArea=4.Q7_Qalc
= i 1 I I I I I
9 _ _ _I
y 82" / 7— I � f II T 1 T
7� / , 1 4 I— - 1 I 1 1 1
3 - i 1 1 1 1 1
LL 6� A— 1 I I 1
5� / fi -1 — — -1 — t — — — — t — I— —
-
4� / 7—
= i I I 1
3 -/ 7— —1 1
2 -/ k 1- — I— —1
/////
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

BMP Calculations:

Time of Concentration - BMP DA Pre-Developed TOC
Pre Developed Drainage Area
Sheet Flow:
n: 0.15
L: 100 ft
P2: 3.55 in
s: 0.050 ft/ft
T: 0.107 hr
Shallow Concentrated Flow:
L: 222 ft
s: 0.050 ft/ft
Type 2 (1=paved/2= unpaved)
V= 3.61 fps
T= 0.017 hr
Open Channel:
L: 260 ft
V: 5 fps (assumed)
T= 0.014 hr
Total: 0.139 hr
8.3 min

Table 8.03h Roughness Surface description n'
coefficients (Manning's n)
for sheet flow Smooth surface(concrete,asphalt,gravel,or tare 0.011
soil)
Fallow(no residue) 0.05
Cu thy aled soils.
Residue cover 5 20% 0.06
Residue cover>20% ... 0.17
Grass.
Short grass praries 0.15
Dense grasses- 0.24
Bennudagrass 0.41
Range(nutal).. 0.12
Woods:
Light underbrush 0.40
Dense undertnish 0.80
1 The n values we a ccsrposile of 1nfamtefon coupled by Ergmen(1986).
2 Irelades species such as weeping love 'ass,bluegrass,buffalo grass,blue grama
grass,and relive grass mixtures.
3 When scleiivg n,consider corer to a heigrl of about 0.1 It.This is tie only red al
Mr plant cover that vi obstruct sleet Tow.
For sheet flow of less than 300 feet,use Manning's kinematic solution
(Overtop and Mcadews 1976)to compute T.:
Equation 8A3g T = 0.007(nLp"
where:
T.=Travel time(hr)
n =Manning's roughness coefficient(Table l(.03h)
L =flow Iaigth(ft)
P2=2-year,24-hour raintall(n)
s =slope of hydraulic grade line(land slope,f fl)
estimate travel time for the shallow concentrated flow segment.
Open channels
Opal channels arc assumed to begin where surveyed cross section information
has been obtained,where channels arc vis irle on aerial photographs,or where
blue lines(indicating streams) appear on United States (icological Survey
(US( ) quadrangle sheets. Manning's equation or water surface profile
inonnation can be used to estimate average flow velocity. Average flow
velocity is usually determined for bank full elevation.
Manning's equation is:
1.49rt's
Equation 8.03h V=-
n
where
V=average velocity(ft.'s)
r =hydralic radius(ft)and is equal to a+p.
a=cross sectional flow area(ft')
p.=wetted paimeter(ft)
S =slope of hydraulic grade line(land slope:ft'ft)
n = Mannng's roughness coefficient for open channel flow
%tartning's n values for open channel flow can be obtained from standard
textbooks such as Chow(1959)or Linsley et al.(191S2).After average velocity
is computed using equation 8.03h,Tr for the channel segment can be estimated
using equation(.03e.
Reservoirs or lakes
Sometimes it is necessary to estimate the velocity of flow through a reservoir
or lake at the outlet of a watershed.This travel time is normally very small and
an be assumed as zao.

Travel time(T.)is the ratio of flow length to tiow velocity:
Equation 8.03e L
T 3600V
whet,:
Tr=Travel time I hr)
L =flow length lft)
V= average velocity(ft/s)
3600=con version factor from seconds to hours
Time of concentration(TO is the sumofT.values for the various consecutive
flow segments:
Equation 8.031
=T„ +T, +...Tt.
where:
Tc=time of concentration(hr)
m=number of flow segments

BMP STAGE STORAGE CALCULATION
Area Calculation-Forebay
Area Volume (ac-ft) Volume
Contour sq. ft AC Inc Accum. cu. ft
626 694 0.016 _ 0.0000 0.0000 0
627 899 0.021 0.0182 0.0182 794
628 1128 0.026 0.0232 0.0415 1806
628.5 1253 0.029 0.0137 0.0551 2401
629 1382 0.032 0.0151 0.0702 3059
Area Calculation-Main Pond
Area Volume (ac-ft) _ Volume
Contour sq. ft AC Inc Accum. cu. ft
_ 624 2319 0.053 0.0000 0.0000 _ 0
_ 625 2750 0.063 0.0581 0.0581_ 2531
_ 626 3214 0.074 0.0684 0.1265 _ 5510
627 3713 0.085 0.0794 0.2059 8971
628 4247 0.097 0.0913 0.2972 12948
628.5 4527 0.104 0.0503 0.3476 15141
629 5326 0.122 0.0565 0.4041 17602
Volume Calculation-Permanent Pool
Area Volume (ac-ft) Volume
Contour sq. ft AC Inc Accum. cu. ft
624 2319 0.053 0.0000 0.0000 0
625 2750 0.063 0.0581 0.0581 2531
626 3908 0.090 0.0760 0.1341 5844
627 4612 0.106 0.0977 0.2318 10099
628 5375 0.123 0.1145 0.3464 15087
628.5 5780 0.133 0.0640 0.4104 17875
629 6708 0.154 0.0716 0.4820 20995
Ave. Permanent Pool Depth 3.13 TRUE
Volume Calculation-Temp Pool
Area Volume (ac-ft) Volume_
Contour sq. ft AC Inc Accum. cu. ft
629 6708 0.154 0.0000 0.0000 0
629.5 7800 0.179 0.0832 0.0832 3624
630 8476 0.195 0.0934 0.1766 7691
631 9785 0.225 0.2094 0.3860 16814
632 11036 0.253 0.2388 0.6248 27218
633 12344 0.283 0.2682 0.8931 38902
634 13708 0.315 0.2989 1.1920 51922

Project Name: Stonebow
Project Number: 1018342
Design Requirements: 85% TSS, 70% TP
Given Information:
Land Use: Residential
Drainage Area to Facility(Acres): 3.59 Meck. County(Minimum 10 Ac. Less than 10 Ac requires water balance computations)
Impervious Area (Acres): 2.07
Percent Impervious: 57.6%
Soil Type: BdB2, GsB
Soil Group: C, D
Curve Number(CN) Pre: 78
Curve Number(CN) Post: 79
Time of Concentration Pre (hour): 0.139
Time of Concentration Post (hour): 0.083
Design Storm Rainfall Depth (in): 1.0 (Typically 1")
Detention Time (Day): 2 Meck. County:
4 days - 85%TSS &70% TP (Optimal Efficiency)
2 days - 60%TSS &40% TP (Standard Efficiency)
4 days - 85%TSS &0% TP (TSS- Only Efficiency)
NCDENR:
2 - 5 days - 85%TSS &40% TP
Watershed: Mountain and Piedmont(85% TSS)
Efficiency: NCDENR

Wet Pond Design (NCDENR - 2007)
Project Name: Stonebow
Job Number: 1018342
Step 1: Compute the water quality volume (WQV).
WQv (Ft3) = (3630)X(RD)X(Rv)X (AD)
Where:
WQV =Water Quality Volume (Ft3)
AD = Drainage Area to Wet Pond (acres).
Rv= Volumetric Runoff Coefficient= 0.05 + 0.9 (% Impervious)
RD = Design Storm Rainfall Depth (in). Typically 1.0".
Percent Impervious = 58%
AD = 3.59 acres
RD = 1.0 in
Rv = 0.57
WQv = 7,404 Ft6

Step 2: Determine Surface Area Requirements.
Average Permanent Pool Depth = 3.3 Feet
Percent Impervious = 58%
SA/ DA Ratio = 2.06
Required Surface Area = 3,221 Ft2
Step 3: Preliminary Temporary Water Quality Drawdown Calculations
Pond Height above Orifice = 629.86 feet
Orifice Invert Elevation = 629.00 feet
Pond Surface Area at Height Above Orifice = 8,476 square feet
Pond Surface Area at Orifice Invert Elevation = 6,708 square feet
Orifice Diameter(D) = 1.50 inches = 0.13 feet
Orifice Area (a) = 0.0123 square feet
Average Surface Area (A) = 7,592 square feet
Gravitational Constatnt(g) = 32.2 ft/sec2
Head (H) = 0.80 feet
Discharge Coefficient (C) = 0.6
Time (t) = 229,481 seconds = 2.66 days
Note:
The above calculation is based on the Bernoulli Equation where:
-2 x A
t = :xax (2g)0 x(0 - H05)
Step 4: Compute Site Hydraulic Input Parameters.
Condition Area (Ac) CN Tc (hours)
Pre-developed- Pond Area 3.59 78 0.139
Post-developed - Pond Area 3.59 79 0.083
Results
Condition Q1-year Q10-year Q25-year Q50-year
Pre-developed N/A 18.79 24.33 28.82
Post-developed N/A 4.95 6.24 14.97

Bioretention Calculations:

Project Name: Stonebow
Project Number: 1018342
Design Requirements: 85% TSS Removal
Given Information:
Land Use: Commercial
Drainage Area to Facility(Acres): 0.09 Meck. County(Maximum 10 Ac and 5 Ac per inflow location)
Impervious Area (Acres): 0.07
Percent Impervious: 77.8%
Soil Type: Urban
Soil Group: C
Curve Number(CN) Pre: 78
Curve Number(CN) Post: 98
Time of Concentration Pre (hour): 0.083
Time of Concentration Post(hour): 0.083
Design Storm Rainfall Depth (in): 1.0 (Typically 1")
Detention Time (Day): 0.50 Meck. County:
1.3 days - 85% TSS & 70% TP (Optimal Efficiency)
1 day-85%TSS &60%TP (Standard Efficiency)
NCDENR:
0.5 days
Mimimum Media Depth (Feet): 2
Water Quality Depth (Feet): 1 Meck. County& NCDENR (Maximum of 1 foot)
Coefficient of Permeability for the Filter Media: 0.25 inches/hour
Watershed: Central Catawba- 85% TSS Only
Efficiency: Standard Efficiency

Bioretention (NCDENR - 2007)
Project Name: Stonebow
Job Number: 1018342
Step 1: Compute the water quality volume (WQV).
WQv (Ft3) = (3630)X(RD)X(Rv)X (AD)
Where:
WQV = Water Quality Volume (Ft3)
AD = Drainage Area to Wet Pond (acres).
Rv= Volumetric Runoff Coefficient= 0.05 + 0.9 (% Impervious)
RD = Design Storm Rainfall Depth (in). Typically 1.0".
Percent Impervious = 78%
AD = 0.09 acres
RD = 1.0 in
Rv = 0.75
WQv = 245 Ft'

Step 2: Determine Surface Area Requirements.
Water Quality Depth (Max.: 1 foot) = 1 Foot
Required Surface Area = 245 Ft2
Step 3: Determine Soil Media Types and Depths
Soil Media Type
Target Pollutant: Nitrogen
Percent Sand: 85% - 88%
Percent Organic Matter: 3% - 5%
Percent Fines: 12%
Media Infiltration Rate: 1 in/hr
Soil Media Depth
Type of Plantings: Shrubs and Trees
Media Depth: 3 Feet (Min. 2', Max. 4')
Step 4: Compute Site Hydraulic Input Parameters.
Condition Area (Ac) CN Tc (hours)
Pre-developed 0.09 78 0.083
Post-developed 0.09 98 0.083
Results
Condition Q1-year Q10-year Q25-year Q50-year
Pre-developed
Post-developed

Step 5: Calculate Surface Area and Underdrain Requirements
Where:
ha = Average Head (Ft)
hMaxFlter= Maximum Head on the Filter Bed (Ft) (Maximum of 1.0 Ft)
Af= Surface Area of Bioretention (Ft2)
dF = Depth of Filter Bed (Ft) (Minimum of 2.0 Ft)
k = Coefficient of Permeability for the Sand Filter Bed = 0.5 Ft/day
Drawdown = WQv/(48 Hours x 3,600 sec/hr) (Ft3/Sec).
W Qv= 245 Ft'
Required Af= 245 Ft`
Provided Af= 446 Ft`
Drawdown 0.001 Ft3/Sec
Number of Underdrain Rows Required = 1 (Maximum Spacing = 10 Ft)
Total Length of Underdrain = 36 Ft
Number of Underdrain Perforations = 276 Holes
50% of Perforations = 138 Holes
Area of One Perforation = 0.00077 Ft2
Capacity of One Hole = 0.0069 Ft3/Sec
Total Capacity of Perforations = 0.95 Ft3/Sec
Check:
0.95 Ft3/Sec > 0.001 Ft3/Sec :. GOOD
Capacity of 6" PVC Underdrain at 0.50% Slope = 0.39 Ft3/Sec
Assume 50% Clogging = 0.20 Ft3/Sec
Check:
0.20 Ft3/Sec > 0.001 Ft3/Sec :. GOOD

1S 2S
PRE-DEV POS -DEV
5P
BIORETENTION
Subcat Reach on. Link Routing Diagram for 1018342 Stonebow_Bioretention-COPY
--N__ Prepared by{enter your company name here}, Printed 3/31/2023
HydroCAD®10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC

1018342 Stonebow_Bioretention-COPY Type II 24-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1 S: PRE-DEV
Runoff = 0.46 cfs @ 11.96 hrs, Volume= 0.021 af, Depth= 2.87"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-yr Rainfall=5.18"
Area (ac) CN Description
* 0.090 78
0.090 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 1S: PRE-DEV
Hydrograph
1 1 -k t 0.5 0 Runoff
—
0.48 0.46 cfs 0.46 7 I
—[ 1`ype l 14 .
—
0.44
0042 - / I ± I -1 c yi*IRa fall=5 1 tr
0.3
0.36 I 4 - - A Ru r1-off Ate-a=0-090 ale
0.34
^ °03 ur�ofLVolum-!=0/.0 1 of,
o.2s — Depth= 8r"
3 0.26 L
0 0.24 = / TCi—V.rimiit
0.2 c 7i
0.18
0.16 t 1 1
0.14
0.12 / —
0.08
1— 1 —
0.04 -
0.02
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_Bioretention-COPY Type II 24-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 2S: POST-DEV
Runoff = 0.67 cfs @ 11.95 hrs, Volume= 0.037 af, Depth= 4.94"
Routed to Pond 5P : BIORETENTION
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-yr Rainfall=5.18"
Area (ac) CN Description
* 0.090 98 PAVED PARKING
0.090 100.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 107 0.36 Direct Entry, DIRECT
Subcatchment 2S: POST-DEV
/� Hydrograph
0.75J ❑Runoff
0.71/ 0.67 cfs 1
T 0.65 _ �pe�i 4-111
0.6V 1 1 1 1 1 1(=yr-Aaithair= 1 67
0.55/0.5� + ]— —1 4 RtttloffArea=01090 at
0.45/ 1 1 1 f1 u r�of 1(p1tm! ,=t.0 7
0.4 —1 R t�n9f 1Dept =49 "
0 0.35� b
Flow w h
LL 0.3� 1 L A 11 _ .0 or
0.25/
0.2:/ -h 1 1 -C I=08
0.15: _ I
0.1/
0.05� '� I
5 10 1 5 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_Bioretention-COPY Type 11 24-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 4
Summary for Pond 5P: BIORETENTION
Inflow Area = 0.090 ac,100.00% Impervious, Inflow Depth = 4.94" for 10-yr event
Inflow = 0.67 cfs @ 11.95 hrs, Volume= 0.037 af
Outflow = 0.38 cfs @ 12.04 hrs, Volume= 0.032 af, Atten= 43%, Lag= 5.3 min
Primary = 0.38 cfs @ 12.04 hrs, Volume= 0.032 af
Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Peak Elev= 644.60' @ 12.04 hrs Surf.Area= 517 sf Storage= 679 cf
Plug-Flow detention time= 570.9 min calculated for 0.032 af(87% of inflow)
Center-of-Mass det. time= 509.4 min ( 1,251.8 - 742.4 )
Volume Invert Avail.Storage Storage Description
#1 643.00' 895 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
643.00 334 0 0
644.00 446 390 390
645.00 564 505 895
Device Routing Invert Outlet Devices
#1 Primary 639.00' 18.0" Round Culvert
L= 48.3' RCP, square edge headwall, Ke= 0.500
Inlet/Outlet Invert= 639.00' /637.00' S= 0.0414 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 643.00' Special & User-Defined
Head (feet) 0.00 1.00 2.00 3.00
Disch. (cfs) 0.000 0.001 0.002 0.002
#3 Device 1 644.10' 4.0" x 4.0" Horiz. Orifice/Grate C= 0.600
Limited to weir flow at low heads
Primary OutFlow Max=0.38 cfs @ 12.04 hrs HW=644.59' (Free Discharge)
4-1=Culvert (Passes 0.38 cfs of 18.73 cfs potential flow)
12=Special & User-Defined (Custom Controls 0.00 cfs)
3=Orifice/Grate (Orifice Controls 0.38 cfs @ 3.38 fps)

1018342 Stonebow_Bioretention-COPY Type II 24-hr 10-yr Rainfall=5.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 5
Pond 5P: BIORETENTION
Hydrograph
0.75 / - 1 1 —
- 0.67 cfs ❑❑P ilmary
0.7/ / I I 1 Ir4lbvS) kre = d9d
0.65/ /
0.6V / lie- IvV 661
0.55V / —L rt 1 1 -I rt fi 1- 1 Sti rigs 67J�cf
0.5/
0.45/ / 11 4 1 1 1 - I— - -
o.a� 0.38 cfs 1 T
0 0.35/
II 0.3/ 1— 1 1 -1 H H H1 1 —[ +
: j17' H
.254/0.2
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_Bioretention-COPY Type II 24-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1 S: PRE-DEV
Runoff = 0.60 cfs @ 11.96 hrs, Volume= 0.028 af, Depth= 3.74"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-yr Rainfall=6.18"
Area (ac) CN Description
* 0.090 78
0.090 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 1S: PRE-DEV
Hydrograph
A—
0.65—' 0.60 cfs 0 Runoff
0.6�
0.45 / —h Ru o'■ AFea=0 090 ac
04 ur1of!FVprttmor-9-.028
0.35 Rr?ff Depth9 7tr
LL 0.3� Tc= .0 m i n
0.25 / C N=
0.2 Iv
0.151/
0.1 1/
0.05-
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_Bioretention-COPY Type II 24-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 2S: POST-DEV
Runoff = 0.80 cfs @ 11.95 hrs, Volume= 0.045 af, Depth= 5.94"
Routed to Pond 5P : BIORETENTION
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-yr Rainfall=6.18"
Area (ac) CN Description
* 0.090 98 PAVED PARKING
0.090 100.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 107 0.36 Direct Entry, DIRECT
Subcatchment 2S: POST-DEV
Hydrograph
L 1_ H- T
❑Runoff
008V 0.80 cfs r T T T
0.75V_
0.7 H- T H- 1 H- fi fi2v-y�- R�air�fa�ll=6t.1
0.65/ —1 Iu fl
H H- uff Al ea=0- 0910 ale
0.55V 14 I I - u VP m� 1 O 5 f
0.5. Depth n
0.45VH T-H H -H _ r I
E 0.4. Flow Lengt=h 0
0.35/L_ I I H- T L I I I H- H L I I Tb .011 Orr
0.3V
T T 1 T 7 T T 1 —ta=cit
0.15y/_ IrtT � I I rtfir
0.1 I -I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

1018342 Stonebow_Bioretention-COPY Type 1124-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 8
Summary for Pond 5P: BIORETENTION
Inflow Area = 0.090 ac,100.00% Impervious, Inflow Depth = 5.94" for 25-yr event
Inflow = 0.80 cfs @ 11.95 hrs, Volume= 0.045 af
Outflow = 0.43 cfs @ 12.04 hrs, Volume= 0.040 af, Atten= 46%, Lag= 5.6 min
Primary = 0.43 cfs @ 12.04 hrs, Volume= 0.040 af
Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs
Peak Elev= 644.74' @ 12.04 hrs Surf.Area= 533 sf Storage= 752 cf
Plug-Flow detention time= 481.7 min calculated for 0.040 af(89% of inflow)
Center-of-Mass det. time= 425.3 min ( 1,164.9 - 739.6 )
Volume Invert Avail.Storage Storage Description
#1 643.00' 895 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
643.00 334 0 0
644.00 446 390 390
645.00 564 505 895
Device Routing Invert Outlet Devices
#1 Primary 639.00' 18.0" Round Culvert
L= 48.3' RCP, square edge headwall, Ke= 0.500
Inlet/Outlet Invert= 639.00' /637.00' S= 0.0414 '/' Cc= 0.900
n= 0.013, Flow Area= 1.77 sf
#2 Device 1 643.00' Special & User-Defined
Head (feet) 0.00 1.00 2.00 3.00
Disch. (cfs) 0.000 0.001 0.002 0.002
#3 Device 1 644.10' 4.0" x 4.0" Horiz. Orifice/Grate C= 0.600
Limited to weir flow at low heads
Primary OutFlow Max=0.43 cfs @ 12.04 hrs HW=644.73' (Free Discharge)
4-1=Culvert (Passes 0.43 cfs of 19.00 cfs potential flow)
12=Special & User-Defined (Custom Controls 0.00 cfs)
3=Orifice/Grate (Orifice Controls 0.43 cfs @ 3.84 fps)

1018342 Stonebow_Bioretention-COPY Type II 24-hr 25-yr Rainfall=6.18"
Prepared by {enter your company name here} Printed 3/31/2023
HydroCAD® 10.10-7a s/n 11406 ©2021 HydroCAD Software Solutions LLC Page 9
Pond 5P: BIORETENTION
Hydrograph
L I _[ L A ❑ Inflow
A 0.80 cfS 1 1 1 1 1 ❑Primary
0.85
o 8 I r�fl A -eTa= 69� arc
0.75k z— 7 T 17 171 71 7 7 Fie k-_El vc644i
0.7� z-
0.65 / rt 1 1 11 rt 1- 1 Sttrrg 'ir.5�Z f
0.6/ z
0.55 ' 1 - rt fi fi
w 0.5:
; 0.45� o.43cfs � fi
0 0.4: '0.35iv z- 1 —[ 1—
0.3 /0.25 1 1 ii
0.15i
0.057 /////
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Buoyancy Calculations:

Bouyancy Calculations- BMP
Volume of Water Displaced (Structure):
Structure Dimensions:
Inner Length = 4 Feet
Inner Width = 4 Feet
Thickness = 0.58 Feet
Height = 4 Feet
Volume = 107 Cubic Feet
Specific Weight of Water= 62.4 Pounds per Cubic Foot
Weight of Displaced Volume = 6,646 Pounds
Volume of Water Displaced (Base):
Structure Dimensions:
Flange = 1.92 Feet
Length = 9 Feet
Width = 9 Feet
Height = 2.5 Feet
Volume = 203 Cubic Feet
Specific Weight of Water= 62.4 Pounds per Cubic Foot
Weight of Displaced Volume = 12,636 Pounds
Total Weight of Displaced Volume = 19,282 Pounds

Concrete Volume of Structure:
Concrete Volume:
Inner Length = 4 Feet
Inner Width = 4 Feet
Thickness = 0.58 Feet
Height = 4 Feet
Volume = 43 Cubic Feet
Specific Weight of Concrete = 150 Pounds per Cubic Foot
Weight of Concrete = 6,375 Pounds
Volume of Concrete Required (Base):
Concrete Volume:
Flange = 1.92 Feet
Length = 9 Feet
Width = 9 Feet
Height = 2.5 Feet
Volume = 203 Cubic Feet
Specific Weight of Concrete = 150 Pounds per Cubic Foot
Weight of Concrete = 30,375 Pounds
Total Weight of Concrete = 36,750 Pounds
Factor of Safety (Minimum = 1) = 1.91

Rip Rap Calculations:

PIPE OUTLET TO FLAT AREA WITH NO DEFINED CHANNEL:
3 Do
La=APRON LENGTH,(FEET)
D =OUTLET PIPE DIAMETER,(INCHES)
ds-MEDIAN STONE SIZE,(FEET) III III MI m
W = Do + La _ ... ... . .. . N
OUTLET 1 2 MIN 90 I I CO i
co•
Z
PIPE 1 I 1 //
DIAMETER,D I I e 3 0
80 I O .0
— m
La ��'( i l l%/ ,A z O
_ TAILWATER < 0.5 Do Va: 70 4 l'/ /r C
-`'� �=-�� PERMANENT GEOTEXTILE FABRIC 0II
OIWA� 3 r
D = 2TIMESTHED50 OF Pe 60 ao�!ia'iiaor�,o -1 -1
STONE DIAMETER BUT NOT LESS ,c�► / II ■' a/ya I .1..
THAN 6-INCHES �G -�- : I . , II
��' 50 II :: :: a' i ik0-a; • * O
■III■1■� •/ ' �
mo::II:I: % _ao - / ta A 4 m
30 a, 4( iiiii ANM% O 0 n
! /,� a,1 I , o m
C
20 a= �F , asi w -
C% i-s"n•i■ n1I —�'' 3 -I 0 m
//■�i111:iI/ IIII�I M'• W —
' 2 "'/immill .ilne'■1■ /'III!I V 1 // • U. 0 N
La=10' I A IIII•III—%r■III■1■ i■MI II I / 'a//. W Z
IIIIIIrs� ■ /IMSIII' I I • O- N `�
.Miles ■W4IIr4 rn //
■--I WA Ir i a In O
IIIIIII— ■IIIn■ —LA■I I//, /AI/i1 IL
IIIIIIII— ■IIIn■ O -- I S.`.I I/I%Co— A
0 nn�1II� ■inn■ i 0 /`,`'°`, /r�OAir u I /%'1 2 p C
1111•11I MMIIMIi //��_a�=� a cv // iiln bill a I N p
- -
IIIIIIII� %1� �� "A IMI1 I --
1111IIll aI-/-/--- ■MIIIII ��1 I
3 m
RECOMMENDED
ECOBMN ENDED MIN IIIIIIII�_ ' �1�'= y� '■IIII I --I m m
_ IIIIIII• J , ■ II r
CLASS B RIP RAP �/ , ' /1 G
m
III 11 z
0
3 5 10 20 50 100 200 500 1000
91
Q=8.55CFS C
r
r
DISCHARGE, FT3/SEC

PIPE OUTLET TO FLAT AREA WITH NO DEFINED CHANNEL:
3 Do
A L APRON LENGTH,(FEET)
1 T - D,=OUTLET PIPE DIAMETER,(INCHES) 0
d =MEDIAN STONE SIZE,(FEET) RI
50
y
w = oo + Lo
OUTLET ' 2 MIN 90 I co Z
PIPE 1 // AO
DIAMETER,Do I a/ II 0
_ a � 80 i
,A// I/II0
wAR0.5 . . 70 fAf4
� '��� C
II
PERMANENT GEOTEXTILE FABP,IC es.,
D = 2 TIMES THE D5D 0* P` 60 b4 i hM'O> I'll
STONE DIAMETER BUT NOT LESS / ! M —
THAN 6-INCHES ��G� /� /�� - /ILI�III r xj
`���v 50 �6 co-�N a * 0
40 JJ.. , m m.,ii RI tJ1
�' 737030 n��\ �'� . 0 Z Pa CI ni" Tel
1111
Iz
r.
20 — i --,P�' III 3 W — O y
La=8' 10 %%i __ 1M% .#0 I U Z a
LL
1 aM p/ IMW/r/ai ■I re
O o Z
tip` a' MI A
= o`ti a' �i i�iii�in�ii to p
�i---/M//AMIIM■I
"— b aM/_/1'LrMnM■I o 0
'\'b Adraar I MIN II a
d iiis�� 1��0 1•N 1 m
RECOMMENDED MIN / a'1"/"" I_■II■I'll m r
CLASSN / � i 0C
CLASS B RIP RAP G
z
0
5 10 20 50 100 200 500 1000
Q=0.87 CFS C
r
r
DISCHARGE, FT3/SEC

Storm Drainage Calculations:

Storm Sewer Tabulation Page 1
Station Len Drng Area Rnoff Area x C Tc Rain Total Cap Vel Pipe Invert Elev HGL Elev Grnd/Rim Elev Line ID
coeff (I) flow full
Line To !nor Total Inv* Total Inlet Syst Size Slope Dn Up Dn Up Dn Up
Line
(ft) (ac) (ac) (C) (min) (min) (in/hr) (cfs) (cfs) (ft/s) (in) (%) (ft) (ft) (ft) (ft) (ft) (ft)
1 End 21.253 0.00 2.94 0.00 0.00 2.49 0.0 8.0 6.3 15.61 16.99 6.33 24 0.56 629.00 629.12 630.42 630.63 631.25 634.04 STMH-2-FES-1
2 1 38.555 0.51 2.41 0.90 0.46 2.17 5.0 7.9 6.3 13.63 43.86 5.34 24 3.76 629.32 630.77 631.15 632.10 634.04 644.13 CI-3-STMH-2
3 2 40.613 0.00 1.66 0.00 0.00 1.49 0.0 7.8 6.3 9.43 25.63 6.45 18 5.96 630.97 633.39 632.10 634.58 644.13 644.81 STMH-10-CI-3
4 3 51.625 0.14 1.57 0.90 0.13 1.41 5.0 7.7 6.3 8.96 10.54 6.41 18 1.01 637.08 637.60 638.14 638.76 644.81 645.07 CI-12-STMH-10
5 4 61.514 0.06 1.30 0.90 0.05 1.17 5.0 7.5 6.4 7.47 10.54 5.94 18 1.01 637.80 638.42 638.76 639.48 645.07 645.98 CI-15-CI-12
6 5 100.235 0.04 1.24 0.90 0.04 1.12 5.0 7.1 6.5 7.21 7.42 4.79 18 0.50 638.62 639.12 639.81 640.31 645.98 647.19 CI-16-CI-15
7 6 89.552 0.05 1.20 0.90 0.05 1.08 5.0 6.8 6.6 7.08 7.44 4.15 18 0.50 639.32 639.77 640.78 641.11 647.19 651.08 CI-17-CI-16
8 7 35.760 0.08 1.15 0.90 0.07 1.04 5.0 6.6 6.6 6.82 8.01 3.86 18 0.58 639.98 640.19 641.53 641.67 651.08 646.75 DI-18-01-17
9 8 57.550 0.12 0.99 0.90 0.11 0.89 5.0 6.3 6.7 5.92 7.41 3.35 18 0.50 640.39 640.67 642.02 642.17 646.75 646.75 DI-19-01-18
10 9 67.253 0.06 0.87 0.90 0.06 0.78 5.0 6.0 6.7 5.28 7.46 3.32 18 0.50 640.87 641.20 642.26 642.38 646.75 646.75 DI-20-01-19
11 10 57.571 0.13 0.57 0.90 0.12 0.51 5.0 5.7 6.8 3.49 4.50 2.91 15 0.49 641.40 641.68 642.67 642.82 646.75 646.75 DI-21 -01-20
12 11 90.269 0.12 0.44 0.90 0.11 0.39 5.0 5.2 7.0 2.74 4.57 3.14 15 0.50 641.88 642.33 642.89 643.06 646.75 646.75 DI-22-01-21
13 12 38.269 0.31 0.31 0.90 0.28 0.28 5.0 5.0 7.0 1.99 4.54 3.17 15 0.50 642.53 642.72 643.24 643.30 646.75 645.75 DI-23-01-22
14 4 103.848 0.02 0.13 0.90 0.02 0.12 5.0 5.1 7.0 0.82 11.99 1.84 15 3.45 637.80 641.38 638.76 641.73 645.07 646.50 CI-13-CI-12
15 14 22.341 0.08 0.08 0.90 0.07 0.07 5.0 5.0 7.0 0.51 10.22 3.41 15 2.51 641.83 642.39 642.02 642.67 646.50 646.50 CI-14-CI-13
16 14 42.454 0.03 0.03 0.90 0.03 0.03 0.1 0.1 7.0 0.19 6.42 2.06 15 0.99 641.58 642.00 641.73 642.17 646.50 643.92 AD-24-CI-13
17 10 38.749 0.24 0.24 0.90 0.22 0.22 0.1 0.1 7.0 1.52 13.12 2.33 15 4.13 641.40 643.00 642.67 643.49 646.75 652.99 CI-25-01-20
18 8 40.058 0.08 0.08 0.90 0.07 0.07 0.1 0.1 7.0 0.51 21.05 1.36 18 4.02 640.39 642.00 642.02 642.26 646.75 652.45 CI-24-01-18
19 3 48.353 0.09 0.09 0.90 0.08 0.08 5.0 5.0 7.0 0.57 15.10 3.30 18 2.07 637.00 638.00 637.20 638.28 644.81 644.10 BR-11 -STMH-10
20 2 48.965 0.19 0.24 0.90 0.17 0.22 5.0 5.6 6.9 1.48 13.34 4.12 18 1.61 632.61 633.40 632.95 633.86 644.13 645.00 CI-4-01-3
21 20 68.756 0.05 0.05 0.90 0.05 0.05 5.0 5.0 7.0 0.32 14.98 1.86 18 2.04 633.60 635.00 633.86 635.21 645.00 645.00 CI-5-CI-4
22 1 92.444 0.09 0.53 0.90 0.08 0.33 5.0 5.3 7.0 2.26 18.54 2.48 18 3.12 629.32 632.20 631.15 632.77 634.04 638.53 CI-6-STMH-2
Project File: 1018342_Storm.stm Number of lines:27 Run Date: 9/8/2023
NOTES:Intensity=84.35/(Inlet time+15.10)^0.83; Return period=Yrs. 10 ; c=cir e=ellip b=box
Storm Sewers v2022.00

Storm Sewer Tabulation Page 2
Station Len Drng Area Rnoff Area x C Tc Rain Total Cap Vel Pipe Invert Elev HGL Elev Grnd/Rim Elev Line ID
coeff (I) flow full
Line To Incr Total Inv* Total Inlet Syst Size Slope Dn Up Dn Up Dn Up
Line
(ft) (ac) (ac) (C) (min) (min) (in/hr) (cfs) (cfs) (ft/s) (in) (%) (ft) (ft) (ft) (ft) (ft) (ft)
23 22 25.508 0.06 0.44 0.90 0.05 0.24 5.0 5.2 7.0 1.70 10.60 3.90 18 1.02 632.40 632.66 632.81 633.15 638.53 638.37 CI-7-CI-6
24 23 45.131 0.38 0.38 0.50 0.19 0.19 5.0 5.0 7.0 1.34 19.14 4.70 18 3.32 633.50 635.00 633.77 635.43 638.37 639.18 CI-9-CI-7
25 End 26.135 0.06 0.24 0.90 0.05 0.22 0.1 0.8 7.0 1.52 4.55 3.35 15 0.50 628.00 628.13 628.49 628.63 0.00 630.45 CI-27-FES-26
26 25 102.568 0.00 0.18 0.00 0.00 0.16 0.0 0.1 7.0 1.14 8.12 2.58 15 1.58 628.13 629.75 628.72 630.17 630.45 632.57 OFFSET CI-28-
27 26 5.066 0.18 0.18 0.90 0.16 0.16 0.1 0.1 7.0 1.14 18.59 3.15 15 8.29 629.75 630.17 630.17 630.59 632.57 632.36 OFFSET CI-28
Project File: 1018342_Storm.stm Number of lines:27 Run Date: 9/8/2023
NOTES:Intensity=84.35/(Inlet time+15.10)^0.83; Return period=Yrs. 10 ; c=cir e=ellip b=box
Storm Sewers v2022.00

Spread Calculations:

INLET CAPACITY CHART
1
DATE: 9/8/2023
PN:101832 REVISIONS:
TWL
CI:Single Curb Inlet Maximum Allowable Spread:6 Ft
DCI:Double Curb Inlet
Tiiiiiii :Siiii7;.60ii.iiii..i4):i4iiiii .iL&,iiiiiiiiiiiiiiiiiiiiiiitfiiii6iiit.,--1 4 iiiilli-
:::::::i:::i:i: :::i:•:: :::i:•:: ::::::,.....:•:•::_:•:.,,...,•••:..••,,•,:•::.::::::::::::::::::::::::::iii:i:i: ::::::::::::::::::,,,•::„,::,:,. , ,
f,or concrete curn.ana gutter.
Inlet _ Drainage Runoff Surface Q(cfs) i : iMH. . iH; Bypass
Type I. No. Area(ac) C Sub. Total Slope(%) K Spread Intercept Q To Inlet#
CI i 3 i 0.51 i 0.70 i 1.43 1.43 1 LP i LP i 5.03 i 1.43 i 0.00 i -
• r r -, J r 1 2- : 4 I •
CI j 12 i 0.14 i 0.70 : 0.39 0.39 1 LP i LP i 2.13 : 0.39 i 0.00 : -
• r r i J r 1 2- i 4 A •
CI i 15 i 0.06 i 0.70 : 0.17 0.17 1 1.50 i 21.0 i 2.41 : 0.17 i 0.00 i 12
I' r i J r 1 -L : 4 1 •
[ CI j 16 i 0.04 i 0.70 j 0.11 0.11 i 4.30 i 29.0 i 1.70 : 0.11 0.00 i 13
i- + ± : 4 1 •
CI i 17 i 0.05 i 0.70 i 0.14 0.42 i 1.30 i 19.00 : 3.49 : 0.42 i 0.00 i 16
• r r 1 I r 1 : 4 1 •
CI i 13 i 0.02 i 0.70 : 0.06 0.06 1 2.10 i 23.5 i 1.50 1 0.06 i 0.00 i 3
• r r -, I r 1 � 1 4 A •
CI i 14 ; 0.08 i 0.70 : 0.22 0.22 i 1.00 i 19.0 i 2.89 : 0.22 i 0.00 i 13
• r r 1 2 r 1 ÷ T 4 1 •
CI j 25 i 0.24 : 0.70 1 0.67 0.69 1 0.50 i 9.00 : 5.03 1 0.41 i 0.28 i 24
• I' r 4 J r 1 -L 1 4 1 •
CI ; 24 i 0.08 i 0.70 1 0.22 0.22 1 0.50 i 9.0 i 3.29 : 0.20 i 0.02 i 17
• r r 1 1
L r 1 : 4 1
CI i 4 i 0.19 i 0.70 1 0.53 0.53 1 LP i LP 2.60 : 0.53 i 0.00 i 5
• r r 1 I r 1 : 4 I
CI i 5 i 0.05 i 0.70 : 0.14 0.14 1 LP i LP i 1.07 : 0.14 i 0.00 : 4
• r r 1 J r 1 2- T 4 1
CI i 6 i 0.09 i 0.70 : 0.25 0.25 i 6.30 i 32.0 i 2.14 : 0.25 i 0.00 i 28
• r r 1 2 r 1 ÷ T 4 1
CI i 7 i 0.06 : 0.70 1 0.17 0.37 i 3.70 i 26.0 : 2.73 1 0.37 i 0.00 i 28
• r r 4 .1 L r 4 -I- f 1
1
CI i 9 i 0.38 i 0.70 1 1.06 1.06 1 3.30 i 26.0 i 4.15 : 0.86 i 0.20 i 7
• r r 1 1 L r 1 : 4 1
CI i 27 i 0.06 i 0.70 : 0.17 0.17 1 1.70 i 21.0 i 2.35 : 0.17 i 0.00 i -
• r r -, J L I 2- : 4 A
CI j 28 i 0.18 i 0.70 : 0.50 0.50 i 2.60 i 23.5 i 3.28 : 0.50 i 0.00 i 27
• r r i J r 1 2- i 4 A
• r:
. :
F • . _L
! 1 i
. .
i J.-'
r F 1• i 1 i 1 i
. . , .
• 4 t I 1-' ! i•
;. ,
r' r i 4 r 1' ÷ ; . 1 I •
.
• r' r' 4 4
1. 4 -:- t 4 i
1
i .,.
,. ! .
i 1
r F' 1 1 i . 1
.
: r i 1 • i r I i
• r' r' ;
r I
I
,,-. i i 1
• r .
, .1 ,: I ÷. t I ,
.,_ I .
r'
• r' 4- ,r' i 1 t
. i t • i
• i r 1 i
. .; . I
; - 1
F'• : i
2
r' ' i 1•
.
1.
r' r i 1 r 4 i i
.,: 1. t I ,
• r' r' -: 1 4• I
. ; ;
r F' I [ 1 ! 41 I
,-' ' i
r' i 1 1 i
• F i
• r'
,.. ; -i .r 4 i
! i
.
J i 2 i 1 •
r' 1t
4.
:- r' 4 J
I J
t i i
I
r r 1 : ; I- 1 ; 4'
: i
r
1
:- 1 I : :
:- i• -; ; 1
. :

Offsite Drainage Calculations:

Storm Drainage Curb (CI-9):

Cross Section for CURB (CI-9)
Project Description
Solve For Spread
Input Data
Channel Slope 0.043 ft/ft
Discharge 1.08 cfs
Gutter Width 2.0 ft
Gutter Cross Slope 0.020 ft/ft
Road Cross Slope 0.020 ft/ft
Spread 5.2 ft
Roughness Coefficient 0.013
C7
1.3 in
5.2 ft
DA(CI-9):
AREA(AC.) C I(in/hr)
IMPERVIOUS 0.24 0.90 4
NONIMPERVIOUS 0.24 0.22
WEIGHTED C= 0.56 v:1
Q(cfs)= 1.08 H:1
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
OFFSITE DRAINAGE CALCS.fm8 Center [10.03.00.03]
8/7/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

Storm Drainage Curb (CI-17):

Cross Section for CURB (CI-17)
Project Description
Solve For Spread
Input Data
Channel Slope 0.027 ft/ft
Discharge 0.18 cfs
Gutter Width 2.0 ft
Gutter Cross Slope 0.020 ft/ft
Road Cross Slope 0.020 ft/ft
Spread 2.9 ft
Roughness Coefficient 0.013
C7
0.7in
2.B ft
DA(CI-17):
AREA C I (in/hr)
IMPERVIOUS 0.05 0.90 4
NONIMPERVIOUS 0.00 0.22
WEIGHTED C= 0.90 v:1
H:1
Q(cfs) = 0.18
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
OFFSITE DRAINAGE CALCS.fm8 Center [10.03.00.03]
9/14/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

Storm Drainage Curb (CI-24):

Cross Section for CURB (CI-24)
Project Description
Solve For Spread
Input Data
Channel Slope 0.010 ft/ft
Discharge 0.26 cfs
Gutter Width 2.0 ft
Gutter Cross Slope 0.020 ft/ft
Road Cross Slope 0.020 ft/ft
Spread 4.0 ft
Roughness Coefficient 0.013
C7
1.0 in
4. ft
DA(CI-24):
AREA C I (in/hr)
IMPERVIOUS 0.07 0.90 4
NONIMPERVIOUS 0.01 0.22 v. 1
WEIGHTED C= 0.82 H. 1
Q(cfs)= 0.26
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
OFFSITE DRAINAGE CALCS.fm8 Center [10.03.00.03]
8/7/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

Storm Drainage Curb (CI-25):

Cross Section for CURB (CI-25)
Project Description
Solve For Spread
Input Data
Channel Slope 0.010 ft/ft
Discharge 0.70 cfs
Gutter Width 2.0 ft
Gutter Cross Slope 0.020 ft/ft
Road Cross Slope 0.020 ft/ft
Spread 5.8 ft
Roughness Coefficient 0.013
C7
1.4 in
5.8 ft
DA(CI-25):
AREA C I (in/hi-)
IMPERVIOUS 0.18 0.90 4
NONIMPERVIOUS 0.06 0.22 'r': 1N
WEIGHTED C= 0.73 H: 1
Q(cfs) = 0.70
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
OFFSITE DRAINAGE CALCS.fm8 Center [10.03.00.03]
8/7/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

Storm Drainage Curb (CI-27):

Cross Section for CURB (CI-27)
Project Description
Solve For Spread
Input Data
Channel Slope 0.030 ft/ft
Discharge 0.22 cfs
Gutter Width 2.0 ft
Gutter Cross Slope 0.020 ft/ft
Road Cross Slope 0.020 ft/ft
Spread 3.1 ft
Roughness Coefficient 0.013
C7
0.7 in
3.1 ft
DA(CI-27):
AREA C I(in/hr)
IMPERVIOUS 0.06 0.90 4 v: 1
NONIMPERVIOUS 0.00 0.22 H:
WEIGHTED C= 0.90
Q(cfs)= 0.22
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
OFFSITE DRAINAGE CALCS.fm8 Center [10.03.00.03]
8/7/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]

Storm Drainage Curb (OFFSET CI-28):

Cross Section for CURB (OFFSET CI-28)
Project Description
Solve For Spread
Input Data
Channel Slope 0.030 ft/ft
Discharge 0.65 cfs
Gutter Width 2.0 ft
Gutter Cross Slope 0.020 ft/ft
Road Cross Slope 0.020 ft/ft
Spread 4.6 ft
Roughness Coefficient 0.013
C7
1.1 in
4.5 ft
DA(OFFSET CI-28):
AREA C I(in/hr)
IMPERVIOUS 0.18 0.90 4
NONIMPERVIOUS 0.00 0.22 v: 1
WEIGHTED C= 0.90 H:1
Q(cfs)= 0.65
Bentley Systems,Inc. Haestad Methods Solution FlowMaster
OFFSITE DRAINAGE CALCS.fm8 Center [10.03.00.03]
8/7/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown,CT 06795 USA [phone]