Drainage Report Block 29002 Lot 45 · This report outlines the results of a hydrologic and...

F:\Jobfile\0303M\_ENG\Hydrology\Drainage Report 6-25-20.doc

Drainage Report

Prepared For

Block 29002 Lot 45

Montgomery Township

Somerset County, New Jersey VCEA Project Number 0303M

July 17, 2018

Revised August 26, 2019

Revised March 13, 2020

Revised April 21, 2020

Revised May 27, 2020

Revised June 10, 2020

Revised June 26, 2020

Prepared For

CC1377, LLC

36 Brower Lane

Hillsborough, New Jersey 08844

Prepared By:

Van Cleef Engineering Associates, LLC

32 Brower Lane

PO Box 5877

Hillsborough, New Jersey 08844

Michael K. Ford, NJ PE No. 34722

pchristopher

MF sig

1

Table of Contents

Title

1.0 Introduction

2.0 Site Description

2.1 Existing Conditions

2.2 Proposed Conditions

3.0 Methodology

4.0 Stormwater Management Objectives

5.0 Stormwater Runoff Control

6.0 Basin Surface Elevation Summary

7.0 Water Quality

8.0 Groundwater Recharge

9.0 Low Impact Development Techniques

10.0 Storm Sewer Design

11.0 Conclusions

12.0 References

Appendix A-Soil Map, CN Values and Time of Concentration

Appendix B-Reservoirs Report

Appendix C-Pre-Development Hydrographs

Appendix D-Post-Development Hydrographs

Appendix E-Water Quality Calculations

Appendix F-Low Impact Development Checklists

Appendix G-Pipe Calculations

Appendix H-Emergency Spillway Design

Appendix I-Recharge Analysis

Appendix J-Drainage Area Maps

2

1.0 Introduction

This report outlines the results of a hydrologic and hydraulic storm water runoff analysis

conducted by Van Cleef Engineering Associates (VCEA) with regard to the proposed

construction on Block 29002 Lot 45 as designated by the Montgomery Township Tax

Maps. The subject property is approximately 5.00 acres and is located along US-206.

The entire subject property lies in the Highway Commercial (HC) District.

This report has been prepared to summarize stormwater analysis design objectives,

methodologies and calculations for the conveyance of stormwater runoff from the

project area under pre and post-development conditions.

2.0 Site Description

2.1 Existing Conditions

The site presently contains a utility building and a parking lot. The rest of the

property is either wooded or covered with grass. A large patch of dirt lies in the

place of a recently demolished building. The entire site is drained by the storm

sewer network running along US-206. The Existing Drainage Area Map indicates

two drainage areas: Drainage Area DA 1 consists of the disturbed area which is

subject to the runoff reduction rates cited in the N.J.A.C. regulations whereas

Drainage Area DA 1A consists of the undisturbed area that will be drained by the

proposed basin under developed conditions and which is not subject to the

aforementioned reduction rates. The difference in elevation between the eastern

and western portions of the lot is greater than 30 feet. See Appendix I for the

Existing Drainage Areas plan. All the soils within the project area belong to

Hydrologic Group C.

2.2 Proposed Conditions

The proposed development of the site includes the construction of two

residential buildings, an appurtenant parking area, a storm sewer system and a

detention basin. The basin will discharge toward the same storm sewer system

running along US-206 as under existing conditions. Furthermore, there will be a

bypass area not drained by the basin which will also be directed toward the

aforementioned storm sewer system. The new buildings will be serviced by

public water and sewer.

3

3.0 Methodology

The assessment of stormwater runoff has been based upon the Soil Conservation

Service Methodology as described in Technical Release No. 55 (TR-55), “Urban

Hydrology for Small Watershed.” Theoretical storms are modeled with the 24-hour SCS

Unit Dimensionless Hydrograph, utilizing a Type III rainfall distribution and recurrence

intervals of 2, 10 and 100 years using Bentley Pond Pack version 8i . The program is

tailored to model the SCS Method for hydrograph generations and to perform interactive

solutions of continuity equation (outflow = inflow +/- storage) with the intermediate

values of the routing curve obtained through linear interpretation.

For Somerset County, New Jersey these 24-hour rainfall amounts are as follows: 2-Year = 3.34 inches 10-Year = 5.01 inches 100-Year = 8.21 inches

Rainfall intensities have been based upon the Somerset County rainfall

intensity/duration curve for all design storms.

The Soil Conservation Service Soil Survey (SCS) for Somerset County was utilized in

order to classify the soils within the watershed. All the soils within the project area

belong to Hydrologic Soil Group C.

Soil Symbol

Soil Name Hydrologic Soil Group

LbtB Lansdowne silt loam, 2 to 6 percent slopes C RoyB Royce silt loam, 2 to 6 percent slopes C

For detailed soils locations please refer to the soils information in the Appendix.

4.0 Stormwater Management Objectives

The primary objective of the Stormwater Management Plan is to provide water quantity

and quality control. The stormwater management is designed to meet all applicable

regulations. This report was prepared following currently accepted engineering

standards, and the measures proposed are designed to meet the requirements of the

Township of Montgomery, Residential Site Improvements Standards (RSIS), the New

Jersey Department of Environmental Protection (NJAC 7:8-5.2), and the Standards for

Soil Erosion and Sediment Control in New Jersey.

4

5.0 Stormwater Runoff Control

Almost all the runoff generated by the project area will be either conveyed to the

detention basin via the pipe network in the southern portion of the site or conveyed to

the existing storm sewer network running along US-206 via the pipe network located in

the Bypass Area within the northern portion of the site. The post construction allowable

peak flow rates for the point of analysis (See Appendix I) were determined by applying

the reductions required by N.J.A.C. 7:8. This project will add a total of 43,752 square

feet (1.01 acres) of impervious coverage to the existing 90,320 square feet (2.07 acres)

of impervious coverage which will result in a total of 134,072 square feet (3.08 acres)

of impervious coverage. The calculations for and results of our analysis can be found in

the tables below.

Project Area Peak Flow Reductions (POA)

Storm

Frequency

Pre-Development

Condition

Peak Flow CFS (EX.

POA – Disturbed

Area To Be

Reduced)

Pre-Development

Condition

Peak Flow CFS

(EX. POA –

Undisturbed

Area)

Allowable Peak

Flow CFS

Post-

Development

Condition Peak

Flow CFS (PR.

POA)

Water Quality 5.24 0.03 N/A 1.88

2 7.40 0.36 7.04*0.50+0.36=

4.06 4.02

10 13.26 0.85

13.26*0.75+0.85=

10.795 10.46

100 25.18 1.90

25.18*0.80+1.90=

22.044 22.03

6.0 Basin Water Surface Elevation Summary A summary of the basin water surface elevations and outflows for the underground basin facility for the 2-, 10-, and 100-year storm events are shown below in the following table.

5

Basin Outflow Water Surface Elevation Summary:

Detention Basin

Storm Event (Year)

Water Surface Elevation (ft) Outflow (cfs)

Water Quality 100.89 0.00 2 102.17 2.03

10 102.99 5.68 100 103.91 11.91

7.0 Water Quality

The total amount of impervious coverage for the proposed site is 3.08 acres. A sand

bottom infiltration basin will be used to treat paved impervious areas. The infiltration

basin has been designed in accordance with the NJDEP BMP Manual which is approved

for 80% TSS removal. See Appendix for soil data and calculations pertaining to water

quality. Below is a summary of the required and provided TSS removal rate by acreage-

removal rate per total acre of land.

Minimum Required TSS Removal for Proposed Impervious

Area Acres Required TSS

Removal

Total Acreage –Removal

Rates

Proposed Impervious 1.01 80% 0.81

Existing Impervious 2.07 80% 1.66

Totals 3.08 2.47

Required TSS Removal Rate (Acreage-Removal Rate/Total Acres): 80%

Proposed TSS Removal for Proposed Impervious

Area Acres Required TSS

Removal

Total Acreage –Removal

Rates

Proposed Impervious 3.08 80% 2.47

Existing Impervious 0.00 80% 0.00

Totals 3.08 2.47

Proposed TSS Removal Rate (Acreage-Removal Rate/Total Acres): 80%

8.0 Groundwater Recharge

The groundwater recharge amount was calculated using the NJDEP GSR-32

Spreadsheet (See Appendix for Spreadsheet Calculations). The infiltration basin will

6

provide groundwater recharge by infiltrating more than 100 percent of the Annual

Recharge Deficit. The total annual recharge of the site under pre-developed conditions

is 135,266 cf. The annual recharge under post-developed conditions is 88,888 cf

resulting in a deficit of 46,378 cf. The annual recharge volume provided by the

infiltration basin is 233,252 cf and thus the groundwater recharge requirement is

fulfilled. The sand filter will drain within 72 hours (see Appendix F). An infiltration rate

of 0.50 in/hr has been used in the calculations as that is fifty percent of the slowest rate

observed.

9.0 Low Impact Development Techniques

According to the NJDEP Stormwater Management Rules at N.J.A.C. 7:8, the

groundwater recharge, stormwater quality, and stormwater quantity standards

established by the rules for major land development projects must be met by

incorporating nine specific nonstructural stormwater management strategies into the

project’s design to the maximum extent practicable.

The Low Impact Development Checklist was completed to demonstrate incorporation of nonstructural stormwater management strategies in the project’s design. The checklist is included in Appendix F.

The following is a summary of the nonstructural stormwater management strategies

incorporated into the site design:

a. Protect areas that provide water quality benefits or areas particularly susceptible

to erosion and sediment loss.

This project was designed in accordance with the Standards for Soil

Erosion and Sediment Control in New Jersey. As part of the proposed

project, a riprap apron has been designed to control erosion at the

outflow point of the storm sewer network.

b. Minimize impervious surfaces and break up or disconnect the flow of runoff over

impervious surfaces:

Impervious coverage for the site has been minimized so that it is

compliant with local regulations.

c. Maximize the protection of natural drainage features and vegetation.

7

This project is a redevelopment of a property that has been previously

disturbed. There are no natural drainage features to protect. There will

be a loss of vegetation which is necessary in order to construct the two

buildings. However, the proposed plantings depicted on the Landscape

Plan will compensate for this loss of vegetation.

d. Minimize the decrease in the “time of concentration” from pre-construction to

post construction. “Time of concentration” is defined as the time it takes for

runoff to travel from the hydraulically most distant point of the drainage area to

the point of interest within a watershed.

The decrease in the time of concentration has been minimized to the

maximum extent possible.

e. Minimize land disturbance including clearing and grading.

Clearing and grading have been minimized to the maximum extent

practicable.

f. Minimize soil compaction.

Soil compaction will be minimized where feasible.

g. Provide low-maintenance landscaping that encourages retention and planting of

native vegetation and minimizes the use of lawns, fertilizers and pesticides.

The landscape design for this project employs the use of native

ornamental, shade, and shrubs on the site. Because native and

adapted trees and shrubs have been chosen for this project, the

landscape will also require less use of fertilizers and pesticides.

h. Provide vegetated open-channel conveyance systems discharging into and

through stable vegetated areas.

Vegetated open-channel conveyance is proposed to collect and direct

the runoff from the basin.

i. Provide other source controls to prevent or minimize the use or exposure of

pollutants at the site in order to prevent or minimize the release of those

8

pollutants into stormwater runoff. Such source controls include, but are not

limited to:

1. Site design features that help to prevent accumulation of trash and debris

in drainage systems.

Proposed inlets on site will comply with the NJPDES storm drain

inlet criteria. Eco-curbs or approved equal, which are catch basin

curb tops, will be provided. They will have debris retention

openings to prevent debris from entering the storm drainage

system.

2. Site design features that help to prevent discharge of trash and debris

from drainage systems.

The outlet structure trash rack will trap the larger debris and

floatables discharged from the site. It is anticipated that no

large floatables will be discharged from the basin as the majority

of impervious pavement surfaces are routed through storm

grates.

3. Site design features that help to prevent and/or contain spills or other

harmful accumulations of pollutants at industrial or commercial

developments; and

This development is neither an industrial development nor a

commercial development.

4. When establishing vegetation after land disturbance, applying fertilizer in

accordance with the requirements established under the Soil Erosion and

Sediment Control Act, NJSA. 4:24-39 et seq., and implementing rules.

The applicant intends to apply fertilizer in accordance with the

requirements established under the Soil Erosion and Sediment

Control Act.

10.0 Storm Sewer Design

The stormwater management collection system was designed based upon 25-year

storm return frequency. Manning’s Formula with a Manning’s Coefficient of 0.013 for

9

reinforced concrete pipe was utilized for sizing the stormwater pipes. Weighted “C”

values were computed based upon land use. The time of concentration to the various

inlet drainage areas have been designed with a minimum of 10 minutes, and rainfall

intensities were based on the various times of concentration considering travel time

within the stormwater collection system. Flow rates were computed using the Rational

Method (Q = CIA). Calculations are provided in the Appendix.

11.0 Conclusion

The proposed development will reduce the peak flow rate from the developed area for

the 2, 10, and 100 year storms as required, will meet the required 80% TSS removal

rate for all new impervious surfaces, and meets the recharge requirements. The site

closely mirrors existing condition drainage patterns. Accordingly, the new development

will not negatively impact runoff on-site or downstream. The project has been designed

in accordance with the standards set forth by various regulatory agencies including the

Montgomery Township, the Residential Site Improvement Standards, the New Jersey

Department of Environmental Protection, and the New Jersey Department of Agriculture

for Soil Erosion Control Standards in the State of New Jersey. All engineering

calculations and their associated drainage area maps are incorporated in the appendix

for further review.

12.0 References

1. Urban Hydrology for Small Watersheds, TR-55, USDA Soil Conservation Service, June 1986.

2. NJDEP Stormwater Management Rules, NJAC 7:8, June 20, 2016.

3. NJDEP Stormwater Best Management Practices Manual, February 2016.

4. Standards for Soil Erosion and Sediment Control in New Jersey, New Jersey State

Soil Conservation Committee, January 2014.

5. Web Soil Survey, United States Department of Agriculture, Natural Resource Conservation Service, Version 8, 2008.

6. Montgomery Township Land Use Ordinance.

7. Bentley, StormCAD®, Version 8.11.02.75, 2011.

8. Bently, Pond Pack version 8i, 2012.

Appendix A

Soil Map, CN Values and Time of Concentration

Hyd

rolo

gic

Soi

l Gro

up—

Som

erse

t Cou

nty,

New

Jer

sey

Nat

ural

Res

ourc

esC

onse

rvat

ion

Serv

ice

Web

Soi

l Sur

vey

Nat

iona

l Coo

pera

tive

Soi

l Sur

vey

4/25

/201

8P

age

1 of

3

4472880447291044729404472970447300044730304473060

4472880447291044729404472970447300044730304473060

5297

3052

9760

5297

9052

9820

5298

5052

9880

5299

1052

9940

5299

7053

0000

5297

3052

9760

5297

9052

9820

5298

5052

9880

5299

1052

9940

5299

7053

0000

40° 2

4' 2

7'' N

74° 38' 58'' W40

° 2

4' 2

7'' N

74° 38' 46'' W

40° 2

4' 2

1'' N

74° 38' 58'' W

40° 2

4' 2

1'' N

74° 38' 46'' W

N

Map

pro

ject

ion:

Web

Mer

cato

r C

orne

r coo

rdin

ates

: WGS

84

Edge

tics

: UTM

Zon

e 18

N W

GS84

050

100

200

300Fe

et0

1530

6090M

eter

sM

ap S

cale:

1:1

,330

if p

rinte

d on

A la

ndsc

ape

(11"

x 8

.5")

shee

t.

Soi

l Map

may

not

be

valid

at

this

sca

le.

Hydrologic Soil Group

Map unit symbol Map unit name Rating Acres in AOI Percent of AOI

LbtB Lansdowne silt loam, 2 to 6 percent slopes

C 0.4 7.8%

RoyB Royce silt loam, 2 to 6 percent slopes

C 4.6 92.2%

Totals for Area of Interest 5.0 100.0%

Rating Options

Aggregation Method: Dominant Condition

Component Percent Cutoff: None Specified

Tie-break Rule: Higher

Hydrologic Soil Group—Somerset County, New Jersey

Natural ResourcesConservation Service

Web Soil SurveyNational Cooperative Soil Survey

4/25/2018Page 3 of 3

Project By KH Date 8/21/2019Location Montgomery Township, NJ Checked DateSelect One: UndevelopedArea Name EX. DA 1

1. Runoff Curve NumberNames Cover Description Area Product

Soil Name and Hydrologic Group (appendix A)

(cover type, treatment, and hydrologic condition; percent impervious; unconnected/

connected area ratio) Tab 2-2 Fig 2-3 Fig 2-4

acres miles

% CN x areaC Woods: Good Condition 70 1.62 113.4C Open Space: Good Condition 74 1.38 102.12

Totals 3 215.52CN (weighted) = total product/ total area= 215.52

3 Use CN = 71.8

Worksheet 2: Runoff curve number and runoff

CN

Project By KH Date 8/21/2019Location Montgomery Township, NJ Checked DateSelect One: UndevelopedArea Name EX. DA 1A





acres miles

% CN x areaC Woods: Good Condition 70 0.29 20.3C Open Space: Good Condition 74 0.18 13.32

Totals 0.47 33.62CN (weighted) = total product/ total area= 33.62

0.47 Use CN = 71.5


CN

Project By KH Date 8/21/2019Location Montgomery Township, NJ Checked DateSelect One: UndevelopedArea Name EX. DA 1





acres miles

% CN x areaC Paved Parking Lots, Roofs, Driveways, Etc. 98 2.07 202.86


2.07 Use CN = 98.0


CN

Project By KH Date 8/21/2019Location Montgomery Township, NJ Checked DateSelect One: DevelopedPre DevelopedSelect One: Tc Area Name EX. DA 1

Notes: Space for as many as two segments per flow type can be used for each worksheetInclude a Map, schematic, or description of flow segments

Sheet Flow (Applicable to Tc only) Segment ID A-B

1 Surface Description (table 3-1) Grass2 Mannings Roughness Coeff.,n (table 3-1) 0.243 Flow Length, L (total L < 300 ft) ft 1004 Two-yr 24-hr rainfall, P2 in 3.35 land slope, s ft/ft 0.06756 Tt=(0.007*(nL)^0.8/((P2^0.5)*(s^0.4)) Compute Tt hr 0.14 0.14

Shallow Concentrated Flow Segment ID B-C C-D

7 Surface Description (paved or unpaved) Unpaved Paved8 Flow Length, L ft 96 2129 Watercourse Slope, s ft/ft 0.065 0.04

10 Average velocity, V (figure 3-1) ft/s 4.1 411 Tt = L/(3600*V) Compute Tt hr 0.01 0.01 0.02

Channel Flow Segment ID D-POA

12 Cross sectional flow area, a ft^213 Wetted Perimeter, Pw ft14 Hydraulic Radius, r=a/Pw Compute r ft15 Channel Slope, s ft/ft16 Mannings roughness Coeff., n17 V = 1.49(r^(2/3))*(s^(1/2))/n Compute V ft/s 2 Assumed18 Flow Length, L ft 62819 Tt = L/(3600*V) Compute Tt hr 0.09 0.0920 Water shed or Subarea Tc or Tt (add Tt in steps 6, 11,19) hr 0.25

min 15.15

Worksheet 3: Time of Concentration (Tc) or Travel Time (Tt)

Project By KH Date 8/21/2019Location Montgomery, NJ Checked DateSelect One: DevelopedArea Name Basin DA 1





acres miles

% CN x areaC Open Space: Good Condition 74 0.78 57.72C Woods: Good Condition 70 0.01 0.7


0.79 Use CN = 73.9


CN

Project By KH Date 8/21/2019Location Montgomery, NJ Checked DateSelect One: DevelopedArea Name Basin DA 1





acres miles



2.34 Use CN = 98.000


CN

Project By KH Date 8/21/2019Location Montgomery Township, NJ Checked DateSelect One: Developed DevelopedSelect One: Tc Area Name Basin DA 1

Notes: Space for as many as two segements per flow type can be used for each worksheetInclude a Map, schematic, or description of flow segments


1 Surface Description (table 3-1) Asphalt2 Mannings Roughness Coeff.,n (table 3-1) 0.0113 Flow Length, L (total L < 300 ft) ft 1004 Two-yr 24-hr rainfall, P2 in 3.35 land slope, s ft/ft 0.046 Tt=(0.007*(nL)^0.8/((P2^0.5)*(s^0.4)) Compute Tt hr 0.02 0.02

Shallow Concentrated Flow Segment ID B-C

7 Surface Description (paved or unpaved) Paved8 Flow Length, L ft 1839 Watercourse Slope, s ft/ft 0.046

10 Average velocity, V (figure 3-1) ft/s 4.411 Tt = L/(3600*V) Compute Tt hr 0.01 0.01

Channel Flow Segment ID D-POA


min 7.53


Project By KH Date 8/21/2019Location Montgomery, NJ Checked DateSelect One: DevelopedArea Name Bypass DA 1





acres miles

% CN x areaC Open Space: Good Condition 74 1.34 99.16C Woods: Good Condition 70 0.33 23.1


1.67 Use CN = 73.2


CN

Project By KH Date 8/21/2019Location Montgomery, NJ Checked DateSelect One: DevelopedArea Name Bypass DA 1





acres miles



0.74 Use CN = 98.000


CN

Project By KH Date 8/21/2019Location Montgomery Township, NJ Checked DateSelect One: Developed DevelopedSelect One: Tc Area Name Bypass DA 1

Notes: Space for as many as two segements per flow type can be used for each worksheetInclude a Map, schematic, or description of flow segments


1 Surface Description (table 3-1) Grass2 Mannings Roughness Coeff.,n (table 3-1) 0.243 Flow Length, L (total L < 300 ft) ft 1004 Two-yr 24-hr rainfall, P2 in 3.35 land slope, s ft/ft 0.0386 Tt=(0.007*(nL)^0.8/((P2^0.5)*(s^0.4)) Compute Tt hr 0.18 0.18

Shallow Concentrated Flow Segment ID B-C

7 Surface Description (paved or unpaved) Not Paved8 Flow Length, L ft 509 Watercourse Slope, s ft/ft 0.201

10 Average velocity, V (figure 3-1) ft/s 7.2511 Tt = L/(3600*V) Compute Tt hr 0.01 0.01

Channel Flow Segment ID C-POA


min 18.81


Appendix B

Reservoirs Report

khussari

Typewriter

ROUTING SEQUENCE

Table of Contents

6Elevation-Volume-Flow Table (Pond), 100 yearsProposed Pond

4Outlet Input Data, 2 yearsO.C.S.

1Master Network Summary

Subsection: Master Network Summary

Catchments Summary

Peak Flow(ft³/s)

Time to Peak(hours)

HydrographVolume

(ft³)

ReturnEvent

(years)

ScenarioLabel

0.201.35535.0001WQEX. DA 1 PERVIOUS

2.3212.2010,688.00022-YearEX. DA 1 PERVIOUS




0.111.20208.0001WQBASIN DA 1 PERVIOUS

0.8212.153,150.00022-YearBASIN DA 1 PERVIOUS




5.231.107,771.0001WQEX. DA 1 IMPERVIOUS

5.2412.1523,047.00022-YearEX. DA 1 IMPERVIOUS




5.911.108,785.0001WQBASIN DA 1IMPERVIOUS

5.9212.1526,053.00022-YearBASIN DA 1IMPERVIOUS




0.141.40389.0001WQBYPASS DA 1PERVIOUS

1.3212.256,417.00022-YearBYPASS DA 1PERVIOUS




1.871.102,778.0001WQBYPASS DA 1IMPERVIOUS

1.8712.158,239.00022-YearBYPASS DA 1IMPERVIOUS




0.031.3579.0001WQEX. DA 1A PERVIOUS

0.3612.201,647.00022-YearEX. DA 1A PERVIOUS

Page 1 of 727 Siemon Company Drive Suite 200 WWatertown, CT 06795 USA +1-203-755-1666

6/4/2020

Bentley PondPack V8i[08.11.01.56]

Bentley Systems, Inc. Haestad Methods SolutionCenter200527 Basin Design.ppc


Catchments Summary

Peak Flow(ft³/s)

Time to Peak(hours)

HydrographVolume

(ft³)

ReturnEvent

(years)

ScenarioLabel




Node Summary

Peak Flow(ft³/s)

Time to Peak(hours)

HydrographVolume

(ft³)

ReturnEvent

(years)

ScenarioLabel

5.241.108,306.0001WQEX. POA (TO BEREDUCED)

7.4012.1533,735.00022-YearEX. POA (TO BEREDUCED)




1.881.153,167.0001WQPR. POA

4.0212.2034,813.00022-YearPR. POA

10.4612.2564,890.0001010-YearPR. POA

13.1112.2595,200.0002525-YearPR. POA

22.0312.20124,935.000100100-YearPR. POA

0.031.3579.0001WQEX. POA

0.3612.201,647.00022-YearEX. POA

0.8512.203,680.0001010-YearEX. POA

1.2312.205,289.0002525-YearEX. POA

1.9012.208,210.000100100-YearEX. POA

Pond Summary

MaximumPond Storage

(ft³)

MaximumWater

SurfaceElevation

(ft)

Peak Flow(ft³/s)

Time to Peak(hours)

HydrographVolume

(ft³)

ReturnEvent

(years)

ScenarioLabel

(N/A)(N/A)5.951.158,993.0001WQProposedPond (IN)

8,992.000100.890.000.000.0001WQProposedPond (OUT)

(N/A)(N/A)6.7412.1529,202.00022-YearProposedPond (IN)

16,040.000102.172.0312.5020,157.00022-YearProposedPond (OUT)



6/4/2020




Pond Summary

MaximumPond Storage

(ft³)

MaximumWater

SurfaceElevation

(ft)

Peak Flow(ft³/s)

Time to Peak(hours)

HydrographVolume

(ft³)

ReturnEvent

(years)

ScenarioLabel







6/4/2020



Storm Event: Synthetic curve 2YRLabel: O.C.S.

Return Event: 2 yearsSubsection: Outlet Input Data

Requested Pond Water Surface Elevations

ft99.00Minimum (Headwater)

ft0.50Increment (Headwater)

ft104.00Maximum (Headwater)

Outlet Connectivity

E2(ft)

E1(ft)

OutfallDirectionOutlet IDStructure Type

104.00100.90TWForwardOrifice - 1Orifice-Circular

104.00101.90TWForwardWeir - 1Rectangular Weir

(N/A)(N/A)TailwaterTailwater Settings


6/4/2020



Storm Event: Synthetic curve 2YRLabel: O.C.S.

Return Event: 2 yearsSubsection: Outlet Input Data

Structure ID: Orifice - 1Structure Type: Orifice-Circular

1Number of Openings

ft100.90Elevation

in7.5Orifice Diameter

0.60Orifice Coefficient

Structure ID: Weir - 1Structure Type: Rectangular Weir

1Number of Openings

ft101.90Elevation

in13.00Weir Length

(ft^0.5)/s3.00Weir Coefficient

Structure ID: TWStructure Type: TW Setup, DS Channel

Free OutfallTailwater Type

Convergence Tolerances

30Maximum Iterations

ft0.01Tailwater Tolerance(Minimum)

ft0.50Tailwater Tolerance(Maximum)

ft0.01Headwater Tolerance(Minimum)

ft0.50Headwater Tolerance(Maximum)

ft³/s0.001Flow Tolerance (Minimum)

ft³/s10.000Flow Tolerance (Maximum)


6/4/2020



Storm Event: Synthetic curve 100YRLabel: Proposed Pond

Return Event: 100 yearsSubsection: Elevation-Volume-Flow Table (Pond)

Infiltration

No InfiltrationInfiltration Method(Computed)

Initial Conditions

ft99.00Elevation (Water Surface,Initial)

ft³0.000Volume (Initial)

ft³/s0.00Flow (Initial Outlet)

ft³/s0.00Flow (Initial Infiltration)

ft³/s0.00Flow (Initial, Total)

hours0.05Time Increment

2S/t + O(ft³/s)

Flow (Total)(ft³/s)

Infiltration(ft³/s)

Area(ft²)

Storage(ft³)

Outflow(ft³/s)

Elevation(ft)

0.000.000.004,334.000.0000.0099.00

24.690.000.004,555.732,222.2030.0099.50

50.630.000.004,783.004,556.6560.00100.00

77.830.000.005,009.877,004.6550.00100.50

100.510.000.005,195.159,045.5480.00100.90

106.330.030.005,242.009,567.4040.03101.00

136.820.750.005,473.5012,246.0700.75101.50

162.041.220.005,662.3014,473.1231.22101.90

168.541.410.005,710.0015,041.7371.41102.00

203.033.190.006,068.0617,985.7973.19102.50

240.305.720.006,437.0021,111.6075.72103.00

280.638.810.006,974.7224,463.6388.81103.50

324.4712.360.007,534.0028,089.91812.36104.00


6/4/2020



Index

Proposed Pond (Elevation-Volume-Flow Table (Pond), 100 years)...6

P

O.C.S. (Outlet Input Data, 2 years)...4, 5

O

Master Network Summary...1, 2, 3

M


6/4/2020



Storm Event: Synthetic curve 100YRLabel: Proposed Pond (OUT)

Return Event: 100 yearsSubsection: Time vs. Elevation

Time vs. Elevation (ft)

Output Time increment = 0.05 hoursTime on left represents time for first value in each row.

Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Time(hours)

99.0099.0099.0099.0099.000.00

99.0099.0099.0099.0099.000.25

99.0099.0099.0099.0099.000.50

99.0199.0099.0099.0099.000.75

99.0299.0199.0199.0199.011.00

99.0399.0399.0399.0299.021.25

99.0599.0599.0499.0499.041.50

99.0799.0799.0699.0699.051.75

99.1099.0999.0999.0899.082.00

99.1299.1299.1199.1199.102.25

99.1599.1499.1499.1399.132.50

99.1899.1799.1799.1699.162.75

99.2199.2199.2099.1999.193.00

99.2599.2499.2499.2399.223.25

99.2999.2899.2799.2799.263.50

99.3399.3299.3199.3199.303.75

99.3799.3699.3599.3599.344.00

99.4299.4199.4099.3999.384.25

99.4699.4599.4499.4399.434.50

99.5199.5099.4999.4899.474.75

99.5699.5599.5499.5399.525.00

99.6199.6099.5999.5899.575.25

99.6699.6599.6499.6399.625.50

99.7199.7099.6999.6899.675.75

99.7799.7699.7599.7499.726.00

99.8399.8299.8099.7999.786.25

99.8999.8899.8799.8599.846.50

99.9699.9599.9399.9299.906.75

100.03100.02100.0099.9999.977.00

100.11100.09100.08100.06100.057.25

100.19100.17100.16100.14100.127.50

100.27100.26100.24100.22100.217.75

100.37100.35100.33100.31100.298.00

100.47100.45100.43100.41100.398.25

100.58100.56100.53100.51100.498.50

100.70100.68100.65100.63100.608.75

100.83100.81100.78100.75100.739.00

100.97100.95100.92100.89100.869.25

101.11101.08101.06101.03101.009.50

101.22101.20101.18101.16101.139.75

101.33101.31101.29101.27101.2510.00

101.43101.41101.39101.37101.3510.25

101.52101.51101.49101.47101.4510.50


6/5/2020







Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Time(hours)

101.62101.60101.58101.56101.5410.75

101.73101.71101.69101.66101.6411.00

101.89101.85101.82101.79101.7611.25

102.13102.06102.01101.96101.9211.50

102.74102.58102.45102.32102.2211.75

103.87103.70103.47103.20102.9512.00

103.74103.83103.90103.94103.9412.25

103.20103.31103.43103.54103.6512.50

102.77102.84102.92103.01103.1012.75

102.50102.55102.59102.65102.7113.00

102.33102.36102.39102.42102.4613.25

102.20102.23102.25102.27102.3013.50

102.12102.13102.15102.17102.1813.75

102.05102.06102.07102.09102.1014.00

102.00102.01102.02102.03102.0414.25

101.96101.96101.97101.98101.9914.50

101.91101.92101.93101.94101.9514.75

101.87101.88101.89101.90101.9115.00

101.83101.83101.84101.85101.8615.25

101.78101.79101.80101.81101.8215.50

101.73101.74101.75101.76101.7715.75

101.68101.69101.70101.71101.7216.00

101.63101.64101.65101.66101.6716.25

101.58101.59101.60101.61101.6216.50

101.54101.55101.56101.57101.5716.75

101.50101.51101.52101.53101.5317.00

101.46101.47101.48101.49101.4917.25

101.43101.44101.44101.45101.4617.50

101.40101.41101.41101.42101.4217.75

101.37101.38101.38101.39101.3918.00

101.35101.35101.36101.36101.3718.25

101.32101.33101.33101.34101.3418.50

101.31101.31101.31101.32101.3218.75

101.29101.29101.30101.30101.3019.00

101.28101.28101.28101.29101.2919.25

101.27101.27101.27101.27101.2819.50

101.26101.26101.26101.26101.2619.75

101.25101.25101.25101.25101.2520.00

101.24101.24101.24101.24101.2420.25

101.23101.23101.23101.23101.2320.50

101.22101.22101.22101.23101.2320.75

101.21101.22101.22101.22101.2221.00

101.21101.21101.21101.21101.2121.25


6/5/2020







Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Time(hours)

101.20101.20101.20101.21101.2121.50

101.20101.20101.20101.20101.2021.75

101.19101.19101.19101.19101.1922.00

101.18101.19101.19101.19101.1922.25

101.18101.18101.18101.18101.1822.50

101.17101.18101.18101.18101.1822.75

101.17101.17101.17101.17101.1723.00

101.16101.17101.17101.17101.1723.25

101.16101.16101.16101.16101.1623.50

101.15101.16101.16101.16101.1623.75

101.14101.14101.15101.15101.1524.00

101.11101.11101.12101.12101.1324.25

101.08101.08101.09101.09101.1024.50

101.06101.06101.07101.07101.0724.75

101.04101.04101.05101.05101.0525.00

101.03101.03101.03101.04101.0425.25

101.02101.02101.02101.02101.0325.50

101.01101.01101.01101.01101.0225.75

101.00101.01101.01101.01101.0126.00

101.00101.00101.00101.00101.0026.25

100.99101.00101.00101.00101.0026.50

100.99100.99100.99100.99100.9926.75

100.99100.99100.99100.99100.9927.00

100.98100.98100.98100.98100.9927.25

100.98100.98100.98100.98100.9827.50

100.98100.98100.98100.98100.9827.75

100.97100.97100.97100.97100.9728.00

100.97100.97100.97100.97100.9728.25

100.97100.97100.97100.97100.9728.50

100.96100.96100.96100.96100.9728.75

100.96100.96100.96100.96100.9629.00

100.96100.96100.96100.96100.9629.25

100.95100.96100.96100.96100.9629.50

100.95100.95100.95100.95100.9529.75

100.95100.95100.95100.95100.9530.00

100.95100.95100.95100.95100.9530.25

100.95100.95100.95100.95100.9530.50

100.94100.94100.94100.94100.9530.75

100.94100.94100.94100.94100.9431.00

100.94100.94100.94100.94100.9431.25

100.94100.94100.94100.94100.9431.50

100.94100.94100.94100.94100.9431.75

100.93100.93100.94100.94100.9432.00


6/5/2020







Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Elevation(ft)

Time(hours)

100.93100.93100.93100.93100.9332.25

100.93100.93100.93100.93100.9332.50

100.93100.93100.93100.93100.9332.75

100.93100.93100.93100.93100.9333.00

100.93100.93100.93100.93100.9333.25

100.93100.93100.93100.93100.9333.50

100.93100.93100.93100.93100.9333.75

100.92100.92100.92100.92100.9234.00

100.92100.92100.92100.92100.9234.25

100.92100.92100.92100.92100.9234.50

100.92100.92100.92100.92100.9234.75

100.92100.92100.92100.92100.9235.00

100.92100.92100.92100.92100.9235.25

100.92100.92100.92100.92100.9235.50

100.92100.92100.92100.92100.9235.75

100.92100.92100.92100.92100.9236.00

100.92100.92100.92100.92100.9236.25

100.92100.92100.92100.92100.9236.50

100.91100.91100.91100.91100.9236.75

100.91100.91100.91100.91100.9137.00

100.91100.91100.91100.91100.9137.25

100.91100.91100.91100.91100.9137.50

100.91100.91100.91100.91100.9137.75

100.91100.91100.91100.91100.9138.00

100.91100.91100.91100.91100.9138.25

100.91100.91100.91100.91100.9138.50

100.91100.91100.91100.91100.9138.75

100.91100.91100.91100.91100.9139.00

100.91100.91100.91100.91100.9139.25

100.91100.91100.91100.91100.9139.50

100.91100.91100.91100.91100.9139.75

100.91100.91100.91100.91100.9140.00

100.91100.91100.91100.91100.9140.25

100.91100.91100.91100.91100.9140.50

100.91100.91100.91100.91100.9140.75

100.91100.91100.91100.91100.9141.00

100.91100.91100.91100.91100.9141.25

100.91100.91100.91100.91100.9141.50

100.91100.91100.91100.91100.9141.75

100.91100.91100.91100.91100.9142.00

100.91100.91100.91100.91100.9142.25

100.91100.91100.91100.91100.9142.50

100.90100.90100.90100.90100.9042.75


6/5/2020



Appendix C

Pre-Development Hydrographs

Tabl

e of

Con

tent

s

17Un

it Hy

drog

raph

Sum

mar

y, 1

00 y

ears

15Un

it Hy

drog

raph

Sum

mar

y, 1

0 ye

ars

13Un

it Hy

drog

raph

Sum

mar

y, 2

yea

rs

EX. D

A 1A

PER

VIOU

S

11Un

it Hy

drog

raph

Sum

mar

y, 1

00 y

ears

9Un

it Hy

drog

raph

Sum

mar

y, 1

0 ye

ars

7Un

it Hy

drog

raph

Sum

mar

y, 2

yea

rs

EX. D

A 1

PERV

IOUS

5Un

it Hy

drog

raph

Sum

mar

y, 1

00 y

ears

3Un

it Hy

drog

raph

Sum

mar

y, 1

0 ye

ars

1Un

it Hy

drog

raph

Sum

mar

y, 2

yea

rs

EX. D

A 1

IMPE

RVIO

USSt

orm

Eve

nt:

Synt

hetic

curv

e 2Y

RLa

bel:

EX.

DA

1 IM

PERV

IOUS

Retu

rn E

vent

: 2

year

sSu

bsec

tion:

Uni

t Hyd

rogr

aph

Sum

mar

y

Synt

hetic

cur

ve2Y

RSt

orm

Eve

nt

year

s2

Retu

rn E

vent

hour

s72

.00

Dura

tion

in3.

3De

pth

hour

s0.

17Ti

me

of C

once

ntra

tion

(Com

posit

e)ft²

90,1

69.2

0Ar

ea (U

ser D

efin

ed)

hour

s0.

02Co

mpu

tatio

nal T

ime

Incr

emen

tho

urs

12.1

3Ti

me

to P

eak

(Com

pute

d)ft³

/s5.

33Fl

ow (P

eak,

Com

pute

d)ho

urs

0.05

Outp

ut In

crem

ent

hour

s12

.15

Tim

e to

Flo

w (P

eak

Inte

rpol

ated

Out

put)

ft³/s

5.24

Flow

(Pea

k In

terp

olat

edOu

tput

)

Dra

inag

e Ar

ea

98.0

0SC

S CN

(Com

posit

e)ft²

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69.2

0Ar

ea (U

ser D

efin

ed)

in0.

2M

axim

um R

eten

tion

(Per

vious

)

in0.

0M

axim

um R

eten

tion

(Per

viou

s, 2

0 pe

rcen

t)

Cum

ulat

ive R

unof

f

in3.

1Cu

mul

ativ

e Ru

noff

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h(P

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us)

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ff Vo

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e (P

ervi

ous)

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rogr

aph

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me

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a un

der H

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grap

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rve)

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,047

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Volu

me

SCS

Uni

t Hyd

rogr

aph

Para

met

ers

hour

s0.

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me

of C

once

ntra

tion

(Com

posit

e)

hour

s0.

02Co

mpu

tatio

nal T

ime

Incr

emen

t

483.

43Un

it Hy

drog

raph

Sha

peFa

ctor

0.75

K Fa

ctor

1.67

0Re

cedi

ng/R

ising

, Tr/

Tpft³

/s14

.07

Unit

peak

, qp

Page

1 o

f 19

27 S

iem

on C

ompa

ny D

rive

Suite

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ater

tow

n, C

T 06

795

USA

+1-

203-

755-

1666

6/2/

2020

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ley

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11.0

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]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

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ter

2005

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asin

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ign.

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m E

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tic cu

rve

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l: E

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turn

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nt:

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ars

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ectio

n: U

nit H

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grap

h Su

mm

ary

SCS

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t Hyd

rogr

aph

Para

met

ers

hour

s0.

11Un

it pe

ak ti

me,

Tp

hour

s0.

44Un

it re

cedi

ng li

mb,

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hour

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tal u

nit t

ime,

Tb

Page

2 o

f 19

27 S

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on C

ompa

ny D

rive

Suite

200

WW

ater

tow

n, C

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795

USA

+1-

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1666

6/2/

2020

Bent

ley

Pond

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1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

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Labe

l: E

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A 1

IMPE

RVIO

USRe

turn

Eve

nt:

10 y

ears

Subs

ectio

n: U

nit H

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grap

h Su

mm

ary

Synt

hetic

cur

ve10

YRSt

orm

Eve

nt

year

s10

Retu

rn E

vent

hour

s72

.00

Dura

tion

in5.

0De

pth

hour

s0.

17Ti

me

of C

once

ntra

tion

(Com

posit

e)ft²

90,1

69.2

0Ar

ea (U

ser D

efin

ed)

hour

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mpu

tatio

nal T

ime

Incr

emen

tho

urs

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me

to P

eak

(Com

pute

d)ft³

/s8.

13Fl

ow (P

eak,

Com

pute

d)ho

urs

0.05

Outp

ut In

crem

ent

hour

s12

.10

Tim

e to

Flo

w (P

eak

Inte

rpol

ated

Out

put)

ft³/s

7.99

Flow

(Pea

k In

terp

olat

edOu

tput

)

Dra

inag

e Ar

ea

98.0

0SC

S CN

(Com

posit

e)ft²

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0Ar

ea (U

ser D

efin

ed)

in0.

2M

axim

um R

eten

tion

(Per

vious

)

in0.

0M

axim

um R

eten

tion

(Per

viou

s, 2

0 pe

rcen

t)

Cum

ulat

ive R

unof

f

in4.

8Cu

mul

ativ

e Ru

noff

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h(P

ervio

us)

ft³35

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.921

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ff Vo

lum

e (P

ervi

ous)

Hyd

rogr

aph

Volu

me

(Are

a un

der H

ydro

grap

h cu

rve)

ft³35

,791

.000

Volu

me

SCS

Uni

t Hyd

rogr

aph

Para

met

ers

hour

s0.

17Ti

me

of C

once

ntra

tion

(Com

posit

e)

hour

s0.

02Co

mpu

tatio

nal T

ime

Incr

emen

t

483.

43Un

it Hy

drog

raph

Sha

peFa

ctor

0.75

K Fa

ctor

1.67

0Re

cedi

ng/R

ising

, Tr/

Tpft³

/s14

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Unit

peak

, qp

Page

3 o

f 19

27 S

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ompa

ny D

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ater

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+1-

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6/2/

2020

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ley

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ds S

olut

ion

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ter

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m E

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: Sy

nthe

tic cu

rve

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l: E

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IMPE

RVIO

USRe

turn

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nt:

10 y

ears

Subs

ectio

n: U

nit H

ydro

grap

h Su

mm

ary

SCS

Uni

t Hyd

rogr

aph

Para

met

ers

hour

s0.

11Un

it pe

ak ti

me,

Tp

hour

s0.

44Un

it re

cedi

ng li

mb,

Tr

hour

s0.

56To

tal u

nit t

ime,

Tb

Page

4 o

f 19

27 S

iem

on C

ompa

ny D

rive

Suite

200

WW

ater

tow

n, C

T 06

795

USA

+1-

203-

755-

1666

6/2/

2020

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

100Y

RLa

bel:

EX.

DA

1 IM

PERV

IOUS

Retu

rn E

vent

: 10

0 ye

ars

Subs

ectio

n: U

nit H

ydro

grap

h Su

mm

ary

Synt

hetic

cur

ve10

0YR

Stor

m E

vent

year

s10

0Re

turn

Eve

ntho

urs

72.0

0Du

ratio

nin

8.2

Dept

h

hour

s0.

17Ti

me

of C

once

ntra

tion

(Com

posit

e)ft²

90,1

69.2

0Ar

ea (U

ser D

efin

ed)

hour

s0.

02Co

mpu

tatio

nal T

ime

Incr

emen

tho

urs

12.1

3Ti

me

to P

eak

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pute

d)ft³

/s13

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k, C

ompu

ted)

hour

s0.

05Ou

tput

Incr

emen

t

hour

s12

.10

Tim

e to

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w (P

eak

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rpol

ated

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put)

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ow (P

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ated

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Dra

inag

e Ar

ea

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S CN

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posit

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ea (U

ser D

efin

ed)

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eten

tion

(Per

vious

)

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um R

eten

tion

(Per

viou

s, 2

0 pe

rcen

t)

Cum

ulat

ive R

unof

f

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0Cu

mul

ativ

e Ru

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rve)

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posit

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mpu

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nal T

ime

Incr

emen

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it Hy

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ctor

0.75

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Unit

peak

, qp

Page

5 o

f 19

27 S

iem

on C

ompa

ny D

rive

Suite

200

WW

ater

tow

n, C

T 06

795

USA

+1-

203-

755-

1666

6/2/

2020

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

100Y

RLa

bel:

EX.

DA

1 IM

PERV

IOUS

Retu

rn E

vent

: 10

0 ye

ars

Subs

ectio

n: U

nit H

ydro

grap

h Su

mm

ary

SCS

Uni

t Hyd

rogr

aph

Para

met

ers

hour

s0.

11Un

it pe

ak ti

me,

Tp

hour

s0.

44Un

it re

cedi

ng li

mb,

Tr

hour

s0.

56To

tal u

nit t

ime,

Tb

Page

6 o

f 19

27 S

iem

on C

ompa

ny D

rive

Suite

200

WW

ater

tow

n, C

T 06

795

USA

+1-

203-

755-

1666

6/2/

2020

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

2YR

Labe

l: E

X. D

A 1

PERV

IOUS

Retu

rn E

vent

: 2

year

sSu

bsec

tion:

Uni

t Hyd

rogr

aph

Sum

mar

y

Synt

hetic

cur

ve2Y

RSt

orm

Eve

nt

year

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rn E

vent

hour

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.00

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tion

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3De

pth

hour

s0.

25Ti

me

of C

once

ntra

tion

(Com

posit

e)ft²

130,

680.

00Ar

ea (U

ser D

efin

ed)

hour

s0.

03Co

mpu

tatio

nal T

ime

Incr

emen

tho

urs

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2Ti

me

to P

eak

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pute

d)ft³

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pute

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urs

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ut In

crem

ent

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e to

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w (P

eak

Inte

rpol

ated

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put)

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k In

terp

olat

edOu

tput

)

Dra

inag

e Ar

ea

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0SC

S CN

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posit

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ea (U

ser D

efin

ed)

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axim

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eten

tion

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vious

)

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eten

tion

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viou

s, 2

0 pe

rcen

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Cum

ulat

ive R

unof

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mul

ativ

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it Hy

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Unit

peak

, qp

Page

7 o

f 19

27 S

iem

on C

ompa

ny D

rive

Suite

200

WW

ater

tow

n, C

T 06

795

USA

+1-

203-

755-

1666

6/2/

2020

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

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Labe

l: E

X. D

A 1

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IOUS

Retu

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vent

: 2

year

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tion:

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mar

y

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t Hyd

rogr

aph

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met

ers

hour

s0.

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it pe

ak ti

me,

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hour

s0.

67Un

it re

cedi

ng li

mb,

Tr

hour

s0.

84To

tal u

nit t

ime,

Tb

Page

8 o

f 19

27 S

iem

on C

ompa

ny D

rive

Suite

200

WW

ater

tow

n, C

T 06

795

USA

+1-

203-

755-

1666

6/2/

2020

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

10YR

Labe

l: E

X. D

A 1

PERV

IOUS

Retu

rn E

vent

: 10

yea

rsSu

bsec

tion:

Uni

t Hyd

rogr

aph

Sum

mar

y

Synt

hetic

cur

ve10

YRSt

orm

Eve

nt

year

s10

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rn E

vent

hour

s72

.00

Dura

tion

in5.

0De

pth

hour

s0.

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me

of C

once

ntra

tion

(Com

posit

e)ft²

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680.

00Ar

ea (U

ser D

efin

ed)

hour

s0.

03Co

mpu

tatio

nal T

ime

Incr

emen

tho

urs

12.1

9Ti

me

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eak

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pute

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pute

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urs

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ut In

crem

ent

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Tim

e to

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eak

Inte

rpol

ated

Out

put)

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k In

terp

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edOu

tput

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Dra

inag

e Ar

ea

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S CN

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ser D

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vious

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viou

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rcen

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ulat

ive R

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mul

ativ

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posit

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483.

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it Hy

drog

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peFa

ctor

0.75

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ctor

1.67

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cedi

ng/R

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, Tr/

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/s13

.46

Unit

peak

, qp

Page

9 o

f 19

27 S

iem

on C

ompa

ny D

rive

Suite

200

WW

ater

tow

n, C

T 06

795

USA

+1-

203-

755-

1666

6/2/

2020

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

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l: E

X. D

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IOUS

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vent

: 10

yea

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bsec

tion:

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mar

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rogr

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met

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hour

s0.

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it pe

ak ti

me,

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hour

s0.

67Un

it re

cedi

ng li

mb,

Tr

hour

s0.

84To

tal u

nit t

ime,

Tb

Page

10

of 1

927

Sie

mon

Com

pany

Driv

e Su

ite 2

00 W

Wat

erto

wn,

CT

0679

5 U

SA +

1-20

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2/20

20

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

ign.

ppc

Stor

m E

vent

: Sy

nthe

tic cu

rve

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DA

1 PE

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Eve

nt:

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mpu

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nal T

ime

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emen

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me

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pute

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viou

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ulat

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peak

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Page

11

of 1

927

Sie

mon

Com

pany

Driv

e Su

ite 2

00 W

Wat

erto

wn,

CT

0679

5 U

SA +

1-20

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5-16

666/

2/20

20

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

Des

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vent

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ak ti

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cedi

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mb,

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hour

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84To

tal u

nit t

ime,

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Page

12

of 1

927

Sie

mon

Com

pany

Driv

e Su

ite 2

00 W

Wat

erto

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CT

0679

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SA +

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5-16

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20

Bent

ley

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Pack

V8i

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11.0

1.56

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ntle

y Sy

stem

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c. H

aest

ad M

etho

ds S

olut

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2005

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asin

Des

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vent

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vent

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tion

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posit

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ser D

efin

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mpu

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nal T

ime

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emen

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me

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k In

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tput

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viou

s, 2

0 pe

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11Un

it pe

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Page

13

of 1

927

Sie

mon

Com

pany

Driv

e Su

ite 2

00 W

Wat

erto

wn,

CT

0679

5 U

SA +

1-20

3-75

5-16

666/

2/20

20

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

s, In

c. H

aest

ad M

etho

ds S

olut

ion

Cen

ter

2005

27 B

asin

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vent

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ak ti

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hour

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it re

cedi

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mb,

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hour

s0.

84To

tal u

nit t

ime,

Tb

Page

14

of 1

927

Sie

mon

Com

pany

Driv

e Su

ite 2

00 W

Wat

erto

wn,

CT

0679

5 U

SA +

1-20

3-75

5-16

666/

2/20

20

Bent

ley

Pond

Pack

V8i

[08.

11.0

1.56

]Be

ntle

y Sy

stem

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c. H

aest

ad M

etho

ds S

olut

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Cen

ter

2005

27 B

asin

Des

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vent

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posit

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ser D

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Appendix D

Post-Development Hydrographs

Table of Contents

39Unit Hydrograph Summary, 100 years





BYPASS DA 1 PERVIOUS






BYPASS DA 1 IMPERVIOUS






BASIN DA 1 PERVIOUS






BASIN DA 1 IMPERVIOUS

Storm Event: Synthetic curve 1YRLabel: BASIN DA 1 IMPERVIOUS

Return Event: 1 yearsSubsection: Unit Hydrograph Summary

Synthetic curve1YR

Storm Event

years1Return Event

hours72.00Duration

in1.3Depth

hours0.17Time of Concentration(Composite)

ft²101,930.40Area (User Defined)

hours0.02Computational TimeIncrement

hours1.13Time to Peak (Computed)

ft³/s6.07Flow (Peak, Computed)

hours0.05Output Increment

hours1.10Time to Flow (PeakInterpolated Output)

ft³/s5.91Flow (Peak InterpolatedOutput)

Drainage Area

98.00SCS CN (Composite)


in0.2Maximum Retention(Pervious)

in0.0Maximum Retention(Pervious, 20 percent)

Cumulative Runoff

in1.0Cumulative Runoff Depth(Pervious)

ft³8,787.864Runoff Volume (Pervious)

Hydrograph Volume (Area under Hydrograph curve)

ft³8,785.000Volume

SCS Unit Hydrograph Parameters



483.43Unit Hydrograph ShapeFactor

0.75K Factor

1.670Receding/Rising, Tr/Tp

ft³/s15.91Unit peak, qp


6/4/2020






hours0.11Unit peak time, Tp

hours0.44Unit receding limb, Tr

hours0.56Total unit time, Tb


6/4/2020





Synthetic curve2YR

Storm Event

years2Return Event

hours72.00Duration

in3.3Depth









Drainage Area





Cumulative Runoff




ft³26,053.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve10YR

Storm Event

years10Return Event

hours72.00Duration

in5.0Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020





Synthetic curve25YR

Storm Event

years25Return Event

hours24.00Duration

in6.2Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020





Synthetic curve100YR

Storm Event

years100Return Event

hours72.00Duration

in8.2Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020



Storm Event: Synthetic curve 1YRLabel: BASIN DA 1 PERVIOUS


Synthetic curve1YR

Storm Event

years1Return Event

hours72.00Duration

in1.3Depth









Drainage Area





Cumulative Runoff


ft³207.961Runoff Volume (Pervious)


ft³208.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve2YR

Storm Event

years2Return Event

hours72.00Duration

in3.3Depth









Drainage Area





Cumulative Runoff




ft³3,150.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve10YR

Storm Event

years10Return Event

hours72.00Duration

in5.0Depth









Drainage Area





Cumulative Runoff




ft³6,756.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve25YR

Storm Event

years25Return Event

hours24.00Duration

in6.2Depth









Drainage Area





Cumulative Runoff




ft³9,577.000Volume





0.75K Factor




6/4/2020










6/4/2020






Storm Event


hours72.00Duration

in8.2Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020



Storm Event: Synthetic curve 1YRLabel: BYPASS DA 1 IMPERVIOUS


Synthetic curve1YR

Storm Event

years1Return Event

hours72.00Duration

in1.3Depth









Drainage Area





Cumulative Runoff




ft³2,778.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve2YR

Storm Event

years2Return Event

hours72.00Duration

in3.3Depth









Drainage Area





Cumulative Runoff




ft³8,239.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve10YR

Storm Event

years10Return Event

hours72.00Duration

in5.0Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020





Synthetic curve25YR

Storm Event

years25Return Event

hours24.00Duration

in6.2Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020






Storm Event


hours72.00Duration

in8.2Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020



Storm Event: Synthetic curve 1YRLabel: BYPASS DA 1 PERVIOUS


Synthetic curve1YR

Storm Event

years1Return Event

hours72.00Duration

in1.3Depth









Drainage Area





Cumulative Runoff


ft³388.876Runoff Volume (Pervious)


ft³389.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve2YR

Storm Event

years2Return Event

hours72.00Duration

in3.3Depth









Drainage Area





Cumulative Runoff




ft³6,417.000Volume





0.75K Factor




6/4/2020










6/4/2020





Synthetic curve10YR

Storm Event

years10Return Event

hours72.00Duration

in5.0Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020





Synthetic curve25YR

Storm Event

years25Return Event

hours24.00Duration

in6.2Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020






Storm Event


hours72.00Duration

in8.2Depth









Drainage Area





Cumulative Runoff









0.75K Factor




6/4/2020










6/4/2020



Index

BYPASS DA 1 PERVIOUS (Unit Hydrograph Summary, 25 years)...37, 38





BYPASS DA 1 IMPERVIOUS (Unit Hydrograph Summary, 25 years)...27, 28





BASIN DA 1 PERVIOUS (Unit Hydrograph Summary, 25 years)...17, 18





BASIN DA 1 IMPERVIOUS (Unit Hydrograph Summary, 25 years)...7, 8





B


6/4/2020



Appendix E

Water Quality Calculations

Water Quality Calculation Sheet

Basin Drain Time

Slowest Permeability Rate Recorded (SL 1 and 2 Basin Flood) – 1.00 in/hrDesign Permeability Rate – 0.50 in/hrDepth to infiltrate – 1.90 ft = 22.8 inches

22.8 in / 0.50 in per hr = 45.6 hr

Seasonal High Water ClearanceSL #2 – Elevation 104.5Soil Lot Bottom (No Mottles or Water) – Elevation 94.50Basin Bottom Elevation – 99.00Bottom of 6” Sand Layer – 98.50Separation Groundwater and bottom of bmp = 6.00 ft


Catchments SummaryPeak Flow

(ft³/s)Time to Peak

(hours)Hydrograph

Volume(ft³)

ReturnEvent

(years)

ScenarioLabel

5.911.108,785.0001wqBASIN DA 1IMPERVIOUS

0.111.20208.0001wqBASIN DA 1 PERVIOUS1.871.102,778.0001wqBYPASS DA 1

IMPERVIOUS0.141.40389.0001wqBYPASS DA 1

PERVIOUS5.231.107,771.0001wqEX. DA 1 IMPERVIOUS0.201.35535.0001wqEX. DA 1 PERVIOUS0.031.3579.0001wqEX. DA 1A PERVIOUS

Node SummaryPeak Flow

(ft³/s)Time to Peak

(hours)Hydrograph

Volume(ft³)

ReturnEvent

(years)

ScenarioLabel

0.031.3579.0001wqEX. POA5.241.108,306.0001wqEX. POA (TO BE

REDUCED)1.881.153,167.0001wqPR. POA

Pond SummaryMaximum

Pond Storage(ft³)

MaximumWater

SurfaceElevation

(ft)

Peak Flow(ft³/s)

Time to Peak(hours)

HydrographVolume

(ft³)

ReturnEvent

(years)

ScenarioLabel

(N/A)(N/A)5.951.158,993.0001wqProposedPond (IN)

8,992.000100.890.000.000.0001wqProposedPond (OUT)


6/2/2020



F:\Jobfile\0303M\2019 Project\ENG\COR\Applications\P&F Major Site Plan & Bulk Variance\Soil\2b-Soil Log 1-MKF-kp-4-14-2020.doc

FORM 2-B SOIL LOGS AND INTERPRETATIONSomerset County/Montgomery Township

Applicant's Name CC1377, LLC Block 29002 Lot 45Describe in accordance with 7:9A-5.3 (inches top-bottom) all profile pits

Log ID = SL#1 Date: 4/6/20Depth(inches)Top-Bottom

Munsell Color Name and Symbol; Estimated Textural Class; Estimated Volume % CoarseFragment, If Present; Structure; Moist or Dry Consistence; Mottling - Abundance, Size andContrast, If Present

0 - 8” 5YR 4/3 Loam; Granular, Friable

8 - 70” 5YR 4/4 Loam; Subangular Blocky, Friable

70 - 102” 5YR 4/4 Shale & Rounded Cobbles; 15% Loam

102 - 120” 5YR 4/4 Fractured Shale; 10% Loam

No Mottles

No Water

No Machine Refusal

Depth in Inches:1st Seepage NoneInfiltration None24 Hour Static NoneSHWT Date:Highest Mottling NoneNon-soil 102”

Soil Limiting Zones: Depths as Indicated (In Inches):Fractured Rock Substratum (top) 102”Massive Rock Substratum (top)Excessively Coarse Horizon (top to bottom)Excessively Coarse Substratum (top)Hydraulically Restrictive Horizon (top to bottom)Hydraulically Restrictive Substratum (top)Perched Zone of Saturation (top to bottom)Regional Zone of Saturation – (top)Soil Suitability Class (from table 10.1) IIScType of Field (from table 10.1) SRE

I hereby certify that the information furnished on Form 2B of this application is true and accurate. I am aware that falsification of data is a violation of theWater Pollution Control Act (N.J.S.A.58:10a-1 et seq.) and is subject to penalties as prescribed in N.J.A.C.7:14-8. I further certify that all borings andexcavations on this lot have been properly backfilled for safety purposes.

Signature of Site Evaluator Kyle J. Paterson Date: 4/6/2020

Signature of Professional Engineer Date: 4/8/2020 Michael K. Ford, NJ PE License No. 34722

F:\Jobfile\0303M\2019 Project\ENG\COR\Applications\P&F Major Site Plan & Bulk Variance\Soil\3g-Basin Soil Log1-MKF-kp-4-14-2020.doc

Form 3g - Basin Flood Data SheetSomerset County/Montgomery Township

Applicant's Name CC1377, LLC Block 29002 Lot 45

Description of Pit in Which Test was Conducted: 1 Date Tested: 4/6/20

SL#1 - 90”

BASIN FLOOD ID #: SL#1 AREA OF PIT: 50 sq. ft.

Description of Rock Substratum within Test Zone:

ROCK TYPE: Fractured ; FORMATION: Brunswick ; AVERAGE FRACTURE SPACING: 1” +/-

Type of Fractures (check appropriate category):

open (wide), clean – width of openings (mm)

open (wide), infilled with fines – width of openings (mm) 1 tight (closed)

Orientation of Fractures:

horizontal (parallel to pit bottom) or nearly so inclined vertical (parallel to sides of pit) or nearly so

Hardness of Rock: rippable with hand tools not rippable with hand tools, rippable by machine

*Time/Date of first basin flooding: 9:40am – 4/6/20 Volume of water added (gallons) 400

RESULT OF FIRST BASIN FLOODING:

basin drained within 24 hours – indicate time/date 10:55am – 4/6/20

basin not drained within 24 hours – indicate time/date

*Time/Date of second basin flooding: 11:01am – 4/6/20 Volume of water added (gallons): 400

RESULT OF SECOND BASIN FLOODING:

basin drained within 24 hours – indicate time/date 1:51pm – 4/6/20


First filling drained in 95 minutes; Second filling drained in 110 minutes

I hereby certify that the information furnished on this form is true and accurate. I am aware that falsification of data is a violation of theWater Pollution Control Act (N.J.S.A. 58:10A-1 et seq.) and is subject to penalties as prescribed in N.J.A.C. 7:14-8.



F:\Jobfile\0303M\2019 Project\ENG\COR\Applications\P&F Major Site Plan & Bulk Variance\Soil\2b-Soil Log 2-MKF-kp-4-14-2020.doc

FORM 2-B SOIL LOGS AND INTERPRETATIONSomerset County/Montgomery Township

Applicant's Name CC1377, LLC Block 29002 Lot 45Describe in accordance with 7:9A-5.3 (inches top-bottom) all profile pits

Log ID = SL#2 Date: 4/6/20Depth(inches)Top-Bottom

Munsell Color Name and Symbol; Estimated Textural Class; Estimated Volume % CoarseFragment, If Present; Structure; Moist or Dry Consistence; Mottling - Abundance, Size andContrast, If Present

0 - 8” 5YR 4/3 Loam; Granular, Friable

8 - 66” 5YR 4/4 Loam; Subangular Blocky, Friable

66 - 120” 5YR 4/4 Fractured Shale; 15% Loam

No Mottles

No Water

No Machine Refusal

Depth in Inches:1st Seepage NoneInfiltration None24 Hour Static NoneSHWT Date:Highest Mottling NoneNon-soil 66”

Soil Limiting Zones: Depths as Indicated (In Inches):Fractured Rock Substratum (top) 66”Massive Rock Substratum (top)Excessively Coarse Horizon (top to bottom)Excessively Coarse Substratum (top)Hydraulically Restrictive Horizon (top to bottom)Hydraulically Restrictive Substratum (top)Perched Zone of Saturation (top to bottom)Regional Zone of Saturation – (top)Soil Suitability Class (from table 10.1) IISType of Field (from table 10.1) SRE

I hereby certify that the information furnished on Form 2B of this application is true and accurate. I am aware that falsification of data is a violation of theWater Pollution Control Act (N.J.S.A.58:10a-1 et seq.) and is subject to penalties as prescribed in N.J.A.C.7:14-8. I further certify that all borings andexcavations on this lot have been properly backfilled for safety purposes.



F:\Jobfile\0303M\2019 Project\ENG\COR\Applications\P&F Major Site Plan & Bulk Variance\Soil\3g-Basin Soil Log2-MKF-kp-4-14-2020.doc

Form 3g - Basin Flood Data SheetSomerset County/Montgomery Township

Applicant's Name CC1377, LLC Block 29002 Lot 45

Description of Pit in Which Test was Conducted: 2 Date Tested: 4/6/20

SL#2 - 96”

BASIN FLOOD ID #: SL#2 AREA OF PIT: 50 sq. ft.

Description of Rock Substratum within Test Zone:

ROCK TYPE: Fractured ; FORMATION: Brunswick ; AVERAGE FRACTURE SPACING: 1” +/-

Type of Fractures (check appropriate category):

open (wide), clean – width of openings (mm)

open (wide), infilled with fines – width of openings (mm) 1 tight (closed)

Orientation of Fractures:

horizontal (parallel to pit bottom) or nearly so inclined vertical (parallel to sides of pit) or nearly so

Hardness of Rock: rippable with hand tools not rippable with hand tools, rippable by machine

*Time/Date of first basin flooding: 9:05am – 4/6/20 Volume of water added (gallons) 400

RESULT OF FIRST BASIN FLOODING:



*Time/Date of second basin flooding: 9:50am – 4/6/20 Volume of water added (gallons): 400

RESULT OF SECOND BASIN FLOODING:



First filling drained in 15 minutes; Second filling drained in 16 minutes

I hereby certify that the information furnished on this form is true and accurate. I am aware that falsification of data is a violation of theWater Pollution Control Act (N.J.S.A. 58:10A-1 et seq.) and is subject to penalties as prescribed in N.J.A.C. 7:14-8.



use consistent units (e.g. feet & days or inches & hours) Conversion TableInput Values inch/hour feet/day

1.0000 R Recharge (infiltration) rate (feet/day) 0.67 1.330.150 Sy Specific yield, Sy (dimensionless, between 0 and 1)

1.00 K Horizontal hydraulic conductivity, Kh (feet/day)* 2.00 4.0054.500 x 1/2 length of basin (x direction, in feet)21.500 y 1/2 width of basin (y direction, in feet) hours days

0.050 t duration of infiltration period (days) 36 1.5010.000 hi(0) initial thickness of saturated zone (feet)

10.333 h(max) maximum thickness of saturated zone (beneath center of basin at end of infiltration period)0.333 Δh(max) maximum groundwater mounding (beneath center of basin at end of infiltration period)

Ground-waterMounding, infeet

Distance fromcenter of basinin x direction, infeet

0.333 00.333 200.333 400.329 500.001 600.000 700.000 800.000 900.000 1000.000 120

Disclaimer

This spreadsheet solving the Hantush (1967) equation for ground-water mounding beneath an infiltrationbasin is made available to the general public as a convenience for those wishing to replicate valuesdocumented in the USGS Scientific Investigations Report 2010-5102 "Groundwater mounding beneathhypothetical stormwater infiltration basins" or to calculate values based on user-specified site conditions. Anychanges made to the spreadsheet (other than values identified as user-specified) after transmission from theUSGS could have unintended, undesirable consequences. These consequences could include, but may not belimited to: erroneous output, numerical instabilities, and violations of underlying assumptions that areinherent in results presented in the accompanying USGS published report. The USGS assumes noresponsibility for the consequences of any changes made to the spreadsheet. If changes are made to thespreadsheet, the user is responsible for documenting the changes and justifying the results and conclusions.

This spreadsheet will calculate the height of a groundwater mound beneath a stormwater infiltration basin. More information can be found in the U.S. Geological SurveyScientific Investigations Report 2010-5102 "Simulation of groundwater mounding beneath hypothetical stormwater infiltration basins".

The user must specify infiltration rate (R), specific yield (Sy), horizontal hydraulic conductivity (Kh), basin dimensions (x, y), duration of infiltration period (t), and the initialthickness of the saturated zone (hi(0), height of the water table if the bottom of the aquifer is the datum). For a square basin the half width equals the half length (x = y).For a rectangular basin, if the user wants the water-table changes perpendicular to the long side, specify x as the short dimension and y as the long dimension. Conversely,if the user wants the values perpendicular to the short side, specify y as the short dimension, x as the long dimension. All distances are from the center of the basin. Userscan change the distances from the center of the basin at which water-table aquifer thickness are calculated.Cells highlighted in yellow are values that can be changed by the user. Cells highlighted in red are output values based on user-specified inputs. The user MUST click theblue "Re-Calculate Now" button each time ANY of the user-specified inputs are changed otherwise necessary iterations to converge on the correct solution will not be doneand values shown will be incorrect. Use consistent units for all input values (for example, feet and days)

In the report accompanying this spreadsheet(USGS SIR 2010-5102), vertical soil permeability(ft/d) is assumed to be one-tenth horizontalhydraulic conductivity (ft/d).

Re-Calculate Now

-0.050

0.000

0.050

0.100

0.150

0.200

0.250

0.300

0.350

0.400

0 20 40 60 80 100 120 140

Groundwater Mounding, in feet

Appendix F

Low Impact Development Checklists

NJD

EP

No

nst

ruct

ura

l S

trat

egie

s P

oin

ts S

yste

m (

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uar

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te:

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pu

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ly

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ject

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13,

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r:

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tes:

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p 1

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de

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ic M

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ify

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in A

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a:

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%):

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tal %

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a:

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par

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us

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56%

%

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over

age

with

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all D

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with

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New Jersey Stormwater BMP Manual . Appendix A: Low Impact Development Checklist . Final Draft . December 2003

F:\Jobfile\0303M\_ENG\Hydrology\Low Impact Development Checklist-180717.doc

Low Impact Development Checklist A checklist for identifying nonstructural stormwater management

Strategies incorporated into proposed land development

Municipality: Montgomery Township

County: Somerset Date: August 22, 2019

Review board or agency: Montgomery Township Planning Board and the Somerset

County Planning Board.

Proposed land development name: Preliminary & Final Site Plan

Lot(s): 45 Block(s): 29002

Project or application number: 0303M

Applicant’s name: CC1377, LLC

Applicant’s address: 36 Brower Lane, Hillsborough, NJ 08844

Telephone: 908-359-3276 Fax: 908-359-3998

Email address: [email protected]

Designer’s name: Michael K. Ford, P.E. c/o Van Cleef Engineering Associates

Designer’s address: 32 Brower Lane, PO Box 5877, Hillsborough, NJ 08844

Telephone: 908-359-8291 Fax: 908-359-1580

Email address: [email protected]



Part 1: Description of Nonstructural Approach to Site Design

In narrative form, provide an overall description of the nonstructural stormwater management

approach and strategies incorporated into the proposed site’s design. Attach additional pages as

necessary. Details of each nonstructural strategy are provided in Part 3 below.

Multiple low impact development BMPs have been used in the design of the proposed site plan.

Landscape and soil disturbance has been minimized by maintaining a significant difference in

elevation between the eastern and western portions of the property with the help of a retaining

wall. The open spaces on-site will provide low maintenance landscaping and will minimize the

use of fertilizers and pesticides.



Part 2: Review of Local Stormwater Management Regulations

Title and date of stormwater management regulations used in development design:

Montgomery Township Stormwater Ordinance

Do regulations include nonstructural requirements? Yes: X No:

If yes, briefly describe: A total of nine (9) strategies are to be used to meet the groundwater

recharge stormwater quality and stormwater quantity requirements prior to utilizing structural

stormwater management measures. These nine strategies are listed in the Drainage Report

List LID-BMPs prohibited by local regulations: ______________________________

Pre-design meeting held? Yes: Date: No: X

Meeting held with:

Pre-design site walk held? Yes: Date: No: X

Site walk held with:

Other agencies with stormwater review jurisdiction:

Name: Somerset-Union Soil Conservation District________________________

________________________________ ________________________

Required approval: Certification __________________

Name: Somerset County Planning Board

Required approval: Conditional Approval

Name:



Part 3: Nonstructural Strategies and LID-BMPs in Design

3.1 Vegetation and Landscaping

Effective management of both existing and proposed site vegetation can reduce a development’s adverse

impacts on groundwater recharges and runoff quality and quantity. This section of the checklist helps

identify the vegetation and landscaping strategies and nonstructural LID-BPMs that have been

incorporated into the proposed development’s design to help maintain existing recharge rates and/or

minimize or prevent increases in runoff quantity and pollutant loading.

A. Has an inventory of existing site vegetation been performed? Yes: X No:

If yes, was this inventory a factor in the site’s layout and design? Yes: X No:

B. Does the site design utilize any of the following nonstructural LID-BPMs?

Preservation of natural areas? Yes: X No: If Yes, specify % of site: 2.3%

Native ground cover? Yes: No: X If Yes, specify % of site: ___

Vegetated buffers? Yes: No: X If Yes, specify % of site: ___

C. Do the land development regulations require these nonstructural LID-BMPs?

Preservation of natural areas? Yes: No: X If Yes, specify % of site: __

Native ground cover? Yes: No: X If Yes, specify % of site:

Vegetated buffers? Yes: No: X If Yes, specify % of site:

D. If vegetated filter strips or buffers are utilized, specify their functions:

Reduce runoff volume increases through lower runoff coefficient: Yes: No: X

Reduce runoff pollutant loads through runoff treatment: Yes: No: X

Maintain groundwater recharge by preserving natural areas: Yes: X No:



3.2 Minimize Land Disturbance

Minimizing land disturbance is a nonstructural LID-BMP that can be applied during both the development’s

construction and post-construction phases. This section of the checklist helps identify those land disturbance

strategies and nonstructural LID-BMP’s that have been incorporated into the proposed development’s design to

minimize land disturbance and the resultant change in the site’s hydrologic character.

A. Have inventories of existing site soils and slopes been performed? Yes: X No:

If yes, were these inventories factors in the site’s layout and design? Yes: X No:

B. Does the development’s design utilize any of the following nonstructural LID-BPMs?

Restrict permanent site disturbance by land owners? Yes: No: X

If yes, how:

Restrict temporary site disturbance during construction? Yes: X No:

If yes, how: Site disturbance during construction will be minimized by using current soil erosion

and sediment control practices.

Consider soils and slopes in selecting disturbance limits? Yes: No: X

If yes, how:

C. Specify percentage of site to be cleared: NA_________ Regraded: 97.7

D. Specify percentage of cleared areas done so for buildings: NA

For driveways and parking: NA For roadways: NA

E. What design criteria and/or site changes would be required to reduce the percentages in C and D above?

The site plan has been designed to limit development to eastern portion of site. There are no other changes

that could reduce the percentages.



F. Specify site’s hydrologic soil group (HSG) percentages:

HSG A: HSG B: HSG C: 100 HSG D:

G. Specify percentage of each HSG that will be permanently disturbed:

HSG A: HSG B: HSG C: 97.7 HSG D:

H. Locating site disturbance within areas with less permeable soils (HSG C and D) and minimizing disturbance

within areas with greater permeable soils (HGS A and B) can help maintain groundwater recharge rates and

reduce runoff volume increases. In light of the HSG percentages in F and G above, what other practical

measures if any can be taken to achieve this?

NA: 100% Type C Soil in area of disturbance

I. Does the site include Karst topography? Yes: No: X

If yes, discuss measures taken to limit Karst impacts:

_________________



3.3 Impervious Area Management

New impervious surfaces at a development site can have the greatest adverse effect on groundwater

recharge and stormwater quality and quantity. This section of the checklist helps identify those

nonstructural strategies and LID-BPMs that have been incorporated into a proposed development’s design

to comprehensively manage the extent and impacts of new impervious surfaces.

A. Specify impervious cover at site: Existing: 41.2% Proposed: 60.1%

B. Specify maximum site impervious coverage allowed by regulations: 70%

C. Compare proposed street cartway widths with those required by regulations:

Type of Street Proposed Cartway

Width (feet)

Required Cartway

Width (feet)

Residential access-low intensity

Residential access-medium intensity

Residential access-high intensity with parking 24’ 24’

Residential access-high intensity without

parking

Neighborhood

Minor collector-low intensity without parking

Minor collector-with one parking lane

Minor collector-with two parking lanes

Minor collector-without parking

Major collector

D. Compare proposed parking space dimensions with those required by regulations:

Proposed: 9 x 18 Regulations: 9 x 18

E. Compare proposed number of parking spaces with those required by regulations:

Proposed: 229 Regulations: 225



F. Specify percentage of total site impervious cover created by buildings: 37.9

By driveways and parking: 62.1 By roadways: N/A

G. What design criteria and/or site changes would be required to reduce the percentages in F above?

Reduce the number of parking spaces by two. The cartway widths and the remaining parking spaces are

based on the Residential Site Improvement Standards and are required for the residential use proposed.

____________

H. Specify percentage of total impervious area that will be unconnected:

Total site: 0 Buildings: 0 Driveways and parking: 0 Roads: 0

I. Specify percentage of total impervious area that will be porous:

Total site: 0 Buildings: 0 Driveways and parking: 0 Roads:

J. Specify percentage of total building roof area that will be vegetated: 0

K. Specify percentage of total parking area located beneath buildings: 0

L. Specify percentage of total parking located within multi-level parking deck: 0



3.4 Time of Concentration Modifications

Decreasing a site’s time of concentration (Tc) can lead directly to increased site runoff rates which, in turn,

can create new and/or aggravate existing erosion and flooding problems downstream. This section of the

checklist helps identify those nonstructural strategies and LID-BMPs that have been incorporated into the

proposed development’s design to effectively minimize such Tc decreases.

When reviewing Tc modification strategies, it is important to remember that a drainage area’s Tc should

reflect the general conditions throughout the area. As a result, Tc modifications must generally be applied

throughout a drainage area, not just along a specific Tc route.

A. Specify percentage of site’s total stormwater conveyance system length that will be:

Storm sewer: 100 Vegetated swale: 0 Natural channel: NA

Stormwater management facility: Other:

Note: The total length of the stormwater conveyance systems should be measured from the site’s

downstream property line to the downstream limit of sheet flow at the system’s headwaters.

B. What design criteria and/or site changes would be required to reduce the storm sewer percentages and

increase the vegetated swale and natural channel percentages in A above?

In order to provide swales the limit of disturbance would be increased

C. In conveyance system subareas that have overland or sheet flow over impervious surfaces or turf

grass, what practical and effective site changes can be made to:

Decrease overland flow slope: NA ____________

Increase overland flow roughness: NA



3.5 Preventative Source Controls

The most effective way to address water quality concerns is by pollution prevention. This section of the

checklist helps identify those nonstructural strategies and LID-BMPs that have been incorporated into the

proposed development’s design to reduce the exposure of pollutants to prevent their release into the

stormwater runoff.

A. Trash Receptacles

Specify the number of trash receptacles provided: Two (2) trash enclosures are proposed

Specify the spacing between the trash receptacles: 649 ft

Compare trash receptacles proposed with those required by regulations:

Proposed: 2 Regulations: NA

B. Pet Waste Stations

Specify the number of pet waste stations provided: NA

Specify the spacing between the pet waste stations: NA

Compare pet waste stations proposed with those required by regulations:

Proposed: Regulations:

C. Inlets, Trash Racks and Other Devices that Prevent Discharge of Large Trash and Debris

Specify percentage of total inlets that comply with the NJPDES storm drain inlet criteria: 100

D. Maintenance

Specify the frequency of the following maintenance activities:

Street sweeping: Proposed: Private Regulations:

Litter collection: Proposed: Private Regulations:

Identify other stormwater management measures on the site that prevent discharge of large trash and

debris:

Regular property care by owner.



E. Prevention and Containment of Spills

Identify locations where pollutants are located on the site and the features that prevent these pollutants

from being exposed to stormwater runoff:

Pollutant: NA-None Location:

Feature utilized to prevent pollutant exposure, harmful accumulation or contain spills:

Pollutant: NA Location:









Part 4: Compliance with Nonstructural Requirements

of NJDEP Stormwater Management Rules

1. Based upon the checklist responses above, indicate which nonstructural strategies have been

incorporated into proposed development’s design in accordance with NJAC 7:8-5.3(b):

No. Nonstructural strategy Yes No

1 Protect areas that provide water quality benefits or areas particularly

susceptible to erosion and sediment loss.

X

2 Minimize impervious surfaces and break up or disconnect the flow of

runoff over impervious surfaces.

X

3 Maximize the protection of natural drainage features and vegetation.

X

4 Minimize the decrease in the pre-construction time of concentration

X

5 Minimize land disturbance including clearing and grading.

X

6 Minimize soil compaction.

X

7 Provide low maintenance landscaping that encourages retention and

planting of native vegetation and minimizes the use of lawns, fertilizers

and pesticides.

X

8 Provide vegetated open-channel conveyance systems discharge into and

through stable vegetated areas.

X

9 Provide preventative source controls.

X

2. For those strategies that have not been incorporated into the proposed development’s design, provide

engineering, environmental and/or safety reasons. Attached additional pages as necessary.

See Stormwater Management Report for further discussion of Low Impact Development Techniques.

Appendix G

Pipe Calculations

Block 29002 Lot 45Montgomery Township0303M6/25/20

INLET DRAINAGE AREACOMPOSITE "C" CALCULATIONS

DRAINAGE AREA

Catch Basin I.D. AREA (SF) IMP. O.S. Composite "C" AREA (Ac.)

0.99 0.51

DA-1 CB-1 2,966 1,717 1,249 0.79 0.07DA-2 CB-2 2,166 1,236 930 0.78 0.05

DA-3 CB-3 38,553 34,892 3,661 0.94 0.89DA-4 CB-4 14,052 9,573 4,479 0.84 0.32DA-5 CB-5 13,418 10,640 2,778 0.89 0.31DA-6 CB-6 14,829 13,462 1,367 0.95 0.34DA-7 CB-7 2,589 2,137 452 0.91 0.06DA-8 CB-8 13,466 10,326 3,140 0.88 0.31DA-9 CB-9 10,087 9,463 624 0.96 0.23DA-10 CB-10 7,737 4,202 3,535 0.77 0.18DA-11 CB-11 3,866 3,456 410 0.94 0.09DA-12 CB-12 2,153 1,309 844 0.80 0.05DA-13 CB-13 2,771 1,860 911 0.83 0.06DA-14 CB-14 19,485 286 19,199 0.52 0.45DA-15 CB-15 12,173 169 12,004 0.52 0.28DA-16 CB-16 2,967 0 2,967 0.51 0.07DA-16A CB-16A 2,389 0 2,389 0.51 0.05DA-17 CB-17 8,305 4,847 3,458 0.79 0.19DA-18 CB-18 2,786 0 2,786 0.51 0.06DA-19 CB-19 433 0 433 0.51 0.01DA-20 CB-20 1,799 0 1,799 0.51 0.04DA-21 CB-21 25,249 24,130 1,119 0.97 0.58DA-22 CB-22 2,677 957 1,720 0.68 0.06DA-23 CB-23 2,534 1,188 1,346 0.74 0.06

PIPE CALCULATIONS

Start Node Stop Node Invert (Start) (ft) Invert (Stop) (ft) Length (ft) System Intensity (in/h) System CA (acres) Upstream Inlet Area (acres) Upstream Inlet C Slope (%) Manning's n Diameter (in) Flow (cfs) Capacity (Full Flow) (cfs) Velocity (ft/s) HGL (In) (ft) HGL (Out) (ft)STORM MH-2 EX. L.I. 96.20 94.59 26 6.22 1.34 (N/A) (N/A) 6.2 0.013 24 16.59 56.29 15.58 97.67 95.48

CB-15 CB-16 118.25 113.62 185 6.52 0.43 0.28 0.52 2.5 0.013 15 2.82 10.21 7.11 118.92 114.07CB-1 CB-2 118.76 118.10 66 6.60 0.06 0.07 0.79 1.0 0.013 15 0.37 6.46 2.85 119 118.31CB-2 CB-3 118.00 111.63 157 6.52 0.09 0.05 0.78 4.1 0.013 15 0.62 13.02 5.45 118.31 112.63CB-14 CB-15 121.38 118.35 121 6.58 0.28 0.45 0.52 2.5 0.013 15 1.88 10.23 6.36 121.93 118.92CB-13 CB-14 121.92 121.48 17 6.60 0.05 0.06 0.83 2.5 0.013 15 0.33 10.21 3.82 122.14 121.93CB-3 CB-5 111.53 104.73 170 6.43 1.20 0.89 0.94 4.0 0.013 15 7.77 12.91 11.01 112.63 105.84CB-4 CB-3 112.29 111.63 66 6.60 0.27 0.32 0.84 1.0 0.013 15 1.79 6.46 4.5 112.82 112.63CB-22 CB-23 110.81 110.67 28 6.60 0.04 0.06 0.68 0.5 0.013 15 0.27 4.57 2.04 111.01 110.98CB-23 CB-17 110.57 110.20 74 6.55 0.09 0.06 0.74 0.5 0.013 15 0.56 4.57 2.53 110.98 110.97CB-18 CB-19 107.51 105.95 52 6.32 0.76 0.06 0.51 3.0 0.013 15 4.82 11.19 8.78 108.4 106.53CB-19 CB-20 105.85 102.71 78 6.30 0.76 0.01 0.51 4.0 0.013 15 4.84 12.91 9.77 106.74 103.24CB-17 CB-18 110.10 107.61 83 6.35 0.73 0.19 0.79 3.0 0.013 15 4.65 11.19 8.69 110.97 108.17CB-20 CB-21 102.61 100.35 57 6.27 0.78 0.04 0.51 4.0 0.013 15 4.95 12.91 9.83 103.51 101.38CB-5 CB-7 104.63 103.51 34 6.38 1.80 0.31 0.89 3.3 0.013 15 11.56 11.72 10.89 105.84 104.56CB-6 CB-5 105.39 104.73 66 6.60 0.32 0.34 0.95 1.0 0.013 15 2.15 6.46 4.73 105.97 105.84CB-21 STORM MH-2 100.25 96.30 112 6.25 1.34 0.58 0.97 3.5 0.013 15 8.48 12.13 10.69 101.38 97.67CB-7 CB-8 103.26 100.40 141 6.36 1.85 0.06 0.91 2.0 0.013 18 11.89 14.96 9.39 104.56 101.41CB-8 CB-10 99.90 99.71 38 6.31 2.35 0.31 0.88 0.5 0.013 24 14.94 15.71 5.69 101.42 101.11CB-9 CB-8 101.31 100.65 66 6.60 0.22 0.23 0.96 1.0 0.013 15 1.47 6.46 4.26 101.78 101.42CB-10 STORM MH-1 99.61 99.45 27 6.29 2.49 0.18 0.77 0.6 0.013 24 15.76 17.52 6.31 101.11 100.99CB-12 STORM MH-1 99.70 99.45 18 6.56 0.12 0.05 0.80 1.4 0.013 15 0.82 7.64 0.67 100.99 100.99

STORM MH-1 HW-1 99.45 99.00 74 6.28 2.61 (N/A) (N/A) 0.6 0.013 24 16.52 17.64 6.38 100.99 100.47CB-11 CB-12 99.84 99.70 27 6.60 0.08 0.09 0.94 0.5 0.013 15 0.56 4.57 2.53 100.99 100.99OCS STORM MH-2 98.33 97.35 39 6.60 0.00 (N/A) (N/A) 2.5 0.013 18 8.16 16.65 9.38 99.44 98.13

CB-16 CB-16A 113.52 111.41 105 6.43 0.47 0.07 0.51 2.0 0.013 15 3.02 9.16 6.69 114.22 112.13CB-16A CB-17 111.41 110.2 61 6.38 0.49 0.05 0.51 2 0.013 15 3.16 9.11 6.75 112.13 110.97

khussari

Text Box

Conduit Table

Roof Drain Sizing Sheet Roof Drain Sizing

Building Number Roof Area (SQ. FT.) Size (Inches) Slope (Inch/Foot)

1 24,129 12 1/8

2 24,148 12 1/8

Please note that all roof drains have been sized per the 2015 National Standard Plumbing Code Chapter 13 Section 13.1.10.1 Primary Roof Drainage. See Table 13.6.2 Part 1 enclosed in this appendix. A rainfall rate of five inches per hour was utilized per NJAC 5:23-3.15(b)11.ii, which states that “rainfall rates shall be applied so that the applicable rainfall rate for Burlington and Ocean Counties and all counties south shall be six inches per hour and for Mercer and Monmouth Counties and all counties north, the applicable rainfall rate shall be five inches per hour.” This site is located north of Mercer and Monmouth Counties.

http://epubs.iapmo.org/NSPC/2015/mobile/index.html#p=340

2 of 3 4/11/2019, 12:22 PM

Tailwater > .5 Do (2)

RIPRAP APRON DATA SHEETPROJECT NAME: 1377 US-206 Job #: 0303M

STORM FREQENCIES: 25-Year DATE: 4/21/2020

BY: KH

OUTLET YEAR Q PIPE PIPE TAILWATER La W (beg) W (end) d50

STRUCT. STORM (cfs) HEIGHT (in) WIDTH (in) (ft) (ft) (ft) (ft) (in)

HW-1 25 16.27 24 24 2.72 17.3 6.0 12.9 1.1

Page 1

Appendix H

Emergency Spillway Design

1377 US-206, Montgomery NJ 08558

Project: 1377 US-206 Date: 08/23/19Location: Montgomery Township, Somerset County By: KH

Emergency Spillway

Basin 1

Emergency Spillway - NJDEP Criteria

Peak 100 Year Inflow to Basin = 18.82 cfs

100 Year Inflow Plus 50% = 28.23 cfs

Emergency Spillway = 70.00 LF Broad Crested Weir at Elev = 103.95

Weir Equation: Q = CLH^1.5

Solving for H: = (Q/CL)^0.67

Where: Q = 28.23 cfs L = 70.00 feet C = 2.70 ( Discharge Coefficient ) H = Hydraulic Head over Spillway

Hydraulic Head H = 0.28 ft

Velocity Over Spillway : V = Q/A

Where: Q = 28.23 cfs A = L x H = 19.58 sf

Velocity V= 1.44 fps

Emergency Water Surface Elevation = 103.95 + H = 104.23

Top of Berm = 104.23 + 1 ft (Freeboard)= 105.23

Set Top of Berm Elevation = 105.30

F:\Jobfile\1231H.01\ENG\Hydro\Drainage Report 10-1-18.doc

Appendix I

Recharge Analysis

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over

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Annu

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)

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Land

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es)

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over

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ccup

ied

by B

MP

are

igno

red

in th

ese

calc

ulat

ions

. Res

ults

are

Clim

atic

Fac

tor

C-fa

ctor

1.50

no u

nits

%R

unof

fR

echa

rged

58.2

%%

sens

etiv

e to

dBM

P, m

ake

sure

dBM

P se

lect

ed is

sm

all e

noug

h fo

r BM

P to

em

pty

in le

ss th

an 3

day

s. F

or la

nd

Aver

age

Annu

al P

Pavg

46.0

in%

Rai

nfal

lR

echa

rged

45.4

%%

Segm

ent L

ocat

ion

of B

MP

if yo

u se

lect

"im

perv

ious

are

as" R

WC

will

be m

inim

al b

ut n

ot z

ero

as d

eter

min

ed b

y

Rec

harg

e R

equi

rem

ent

over

Imp.

Are

adr

4.1

inth

e so

il ty

pe a

nd a

sha

llow

root

zon

e fo

r thi

s La

nd C

over

allo

win

g co

nsid

erat

ion

of la

tera

l flo

w a

nd o

ther

loss

es.

How

to s

olve

for d

iffer

ent r

echa

rge

volu

mes

:By

defa

ult t

he s

prea

dshe

et a

ssig

ns th

e va

lues

of t

otal

def

icit

rech

arge

vol

ume

"Vde

f" an

d to

tal p

ropo

sed

impe

rvio

us a

rea

"Aim

p" fr

om th

e "A

nnua

l Rec

harg

e" s

heet

to "V

def"

and

"Aim

p" o

n th

is p

age.

Thi

s al

low

s so

lutio

n fo

r a s

ingl

e BM

P to

han

dle

the

entir

e re

char

ge re

quire

men

t ass

umin

g th

e ru

noff

from

ent

ire im

perv

ious

are

a is

ava

ilabl

e to

the

BMP.

To s

olve

for a

sm

alle

r BM

P or

a L

ID-IM

P to

rech

arge

onl

y pa

rt of

the

rech

arge

requ

irem

ent,

set V

def t

o yo

ur ta

rget

val

ue a

nd A

imp

to im

perv

ious

are

a di

rect

ly c

onne

cted

to y

our i

nfilt

ratio

n fa

cilit

y an

d th

en s

olve

for A

BMP

ordB

MP.

To

go b

ack

to th

e de

faul

t con

figur

atio

n cl

ik th

e "D

efau

lt Vd

ef &

Aim

p" b

utto

n.

10/0

5/17

00

F:\Jobfile\1231H.01\ENG\Hydro\Drainage Report 10-1-18.doc

Appendix J

Drainage Area Maps

Land Surveying Professional Planning Landscape Architecture

Engineering Associates, LLC

FILE No. 3476-L

Consulting Civil, Environmental & Municipal Engineering

Van Cleef

F:\JOBFILE\0303M\_ENG\DWG\EXISTING DA.DWG

ONE

WAY

D

D

S S

D

FL 1SL1

SL 2

FL 2

FL 3

FL 4

FIRE LANEFIRE LANE

FIRE LANE

SHEET FLOW

100 FT. @4.0%

T

c

PATH (TYP) CHANNEL FLOW

881 FT

SHALLOW

CONCENTRATED FLOW

183 FT. @4.6%

SHEET FLOW

100 FT. @3.8%

SHALLOW CONCENTRATED FLOW

50 FT. @20.1%

CHANNEL FLOW

712 FT



FILE No. 3476-L


Van Cleef

F:\JOBFILE\0303M\_ENG\DWG\PROPOSED DA.DWG

ONE

WAY

D

D

S S

S

D

FL 1SL1

SL 2

FL 2

FL 3

FL 4

FIRE LANEFIRE LANE

FIRE LANE

DA-4

0.32

DA-15

0.28

DA-23

0.06

DA-21

0.58

DA-16

0.07

DA-1

0.07

DA-14

0.45

DA-13

0.06

DA-17

0.19

DA-3

0.89

DA-2

0.05

DA-5

0.31

DA-7

0.06

DA-6

0.34

DA-9

0.23

DA-8

0.31

DA-11

0.09

DA-12

0.05

DA-10

0.18

DA-22

0.06

DA-18

0.06

DA-19

0.01

DA-20

0.04

DA-16A

0.05



FILE No. 3476-L


Van Cleef

F:\JOBFILE\0303M\_ENG\DWG\PROPOSED DA.DWG

Drainage Report Block 29002 Lot 45 · This report outlines the results of a hydrologic and...

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