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STORMWATER MANAGEMENT REPORT for 156 East Commodore Boulevard Warehouse Block 2202 Lot 3

JACKSON TOWNSHIP OCEAN COUNTY NEW JERSEY

PREPARED BY:

PROFESSIONAL DESIGN SERVICES, L.L.C. 1245 AIRPORT ROAD SUITE 1 LAKEWOOD, NJ 08701 732-363-0060 PDS Ref. No. 320157

Graham J. Macfarlane, P.E., C. M.E. NJ License No. 37110

December 9, 2025

CONTENTS

I PROJECT DESCRIPTION ..... 1 II EXISTING HYDROLOGY AND SOILS ..... 2 III REGULATORY STANDARDS ..... 3 IV METHODOLOGY ..... 7 V STORMWATER MANAGEMENT PLAN ..... 9

APPENDICES

• A.PRE-DEVELOPED CALCULATIONS
• B.POST-DEVELOPED CALCULATIONS
• C.COLLECTION SYSTEM CALCULATIONS
• D.SOIL EROSION CALCULATIONS
• E.GROUNDWATER MOUNDING

LIST OF FIGURES

1. ROAD MAP
2. TOPOGRAPHIC MAP
3. SOILS MAP

I PROJECT DESCRIPTION

Development of the subject premises known as Block 2202 Lot 3 within Jackson Township, Ocean County, NJ is proposed. The subject parcel encompasses a total land area of approximately 2.2 acres.

It is proposed to develop the site with a new multi-tenant warehouse building in accordance with the Land Use and Development Regulations of Jackson Township. Construction of a Stormwater Management system is proposed for compliance with current regulations of Jackson Township, Ocean County and the Ocean County SCD, as well as the NJ Stormwater Management Rules, NJAC 7:8. This report outlines the methodologies and results for management of the increased stormwater runoff created as a result of the development.

II EXISTING HYDROLOGY & SOILS

The project site lies within the watershed of the South Branch of the Metedeconk River. Figure 2 is a copy of the USGS Quadrangle Topography Map with the site located. The site generally slopes from the west to east. The existing elevations range from about 110 feet above MSL to 120 feet above MSL. Figure 1 is a copy of the site's Location Map. Figure 2 is a copy of the USGS Quadrangle Topography Map with the site located. Development of the site is not restricted by the presence of freshwater wetlands, flood hazard area or Category One Riparian buffers. According to the Ocean County Soil Survey, the following soil types exist on the project site:

Lakewood sand would typically comprised of 90% sand grains. Permeability of the series is rapid, and greater than 2 inches per hour; the series is considered excessively drained. The soil does not retain water for long periods of time. The soil series is not associated with flood plains, and depth to seasonal high water table is typically greater than 6 feet.

Based on the mapping, Berryland Sand is also depicted on site. This soil series is typically poorly drained, and could impose limitations on development based on high water table. However, the site specific soils investigations did not reveal these findings. We would defer to the site specific data and evaluations in lieu of the published data in the Soil Survey.

PDS PROFESSIONAL DESIGN SERVICES, L.L.C. CONSULTING ENGINEERS, LAND SURVEYORS, PLANNERS, ENVIRONMENTAL SCIENTISTS, CONSTRUCTION SERVICES 1245 AIRPORT ROAD, SUITE 1, LAKEWOOD, NEW JERSEY 08701 PHONE 732 363 0060 FAX 732 363 0073 ENGINEERING@PDS-NJ.COM WWW.PDS-NJ.COM NEW JERSEY STATE BOARD OF P.E. & L.S. CERTIFICATE OF AUTHORIZATION NO. 24GA28125400

DCATION MAF FOR BLOCK 2202 LOT 3

TOWNSHIP OF JACKSON OCEAN COUNTY NEW JERSEY

DATE: 08/25/2025

DRAFTED BY: BK DATE: 08/25/2025 PROJECT: 320157

SCALE IN FEET

PROFESSIONAL DESIGN SERVICES, L.L.C.

CONSULTING ENGINEERS, LAND SURVEYORS, PLANNERS, ENVIRONMENTAL SCIENTISTS, CONSTRUCTION SERVICES AIRPORT ROAD, SUITE 1, LAKEWOOD, NEW JERSEY 0870 PHONE 732 363 0060 FAX 732 363 0073 ENGINEERING@PDS-NJ.COM WWW.PDS-NJ.COM NEW JERSEY STATE BOARD OF P.E. & L.S. CERTIFICATE OF AUTHORIZATION NO. 24GA28125400

QUAD MAP

FOR

BLOCK 2202 LOT 3

TOWNSHIP OF JACKSON OCEAN COUNTY NEW JERSEY

DATE: 08/25/2025

DRAFTED BY: BK

PROJECT: 320157

PDS

PROFESSIONAL DESIGN SERVICES, L.L.C. CONSULTING ENGINEERS, LAND SURVEYORS, PLANNERS, ENVIRONMENTAL SCIENTISTS, CONSTRUCTION SERVICES 1245 AIRPORT ROAD, SUITE 1, LAKEWOOD, NEW JERSEY 08701 PHONE 732 363 0060 FAX 732 363 0073 ENGINEERING@PDS-NJ.COM WWW.PDS-NJ.COM NEW JERSEY STATE BOARD OF P.E. & L.S. CERTIFICATE OF AUTHORIZATION NO. 24GA28125400

SOILS MAP

FOR

BLOCK 2202 LOT 3

TOWNSHIP OF JACKSON OCEAN COUNTY NEW JERSEY

DRAFTED BY: BK DATE: 08/25/2025 PROJECT: 320157

DATE: 08/25/2025

Ⅲ

REGULATORY STANDARDS

A. Applicable Regulations

All increased stormwater runoff resulting from the proposed development must be managed both qualitatively and quantitatively in accordance with New Jersey Regulations.

The Flood Hazard Area, Freshwater Wetland Regulations and Residential Site Improvement Standards (RSIS), as administered by the New Jersey Department of Environmental Protection (NJDEP) requires the utilization of best available technology to minimize the amount of stormwater runoff, maintain existing onsite infiltration, simulate natural drainage systems and minimize the discharge of pollutants to ground or surface waters. The overall goal of the post-construction stormwater management system design shall be to meet the erosion control, groundwater recharge, stormwater runoff quantity and quality standards at N.J.A.C. 7:8-5.4 and 5.5.

The stormwater management must be designed to:

1. Reduce flood damage, including damage to life and property;
2. Minimize, to the extent practical, any increase in stormwater runoff from any new development;
3. Reduce soil erosion from any development or construction project;
4. Assure the adequacy of exiting and proposed culverts and bridges, and other in-stream structures;
5. Maintain groundwater recharge;
6. Prevent, to the greatest extent feasible, an increase in nonpoint pollution;
7. Maintain the integrity of stream channels for their biological functions, as well as for drainage;
8. Minimize pollutants in stormwater runoff from new and existing

development in order to restore, enhance and maintain the chemical, physical, and biological integrity of the waters of the State, to protect public health, to safeguard fish and aquatic life and scenic and ecological values and to enhance the domestic, municipal, recreational, industrial and other uses of water; and

9. Protect public safety through the proper design and operation of stormwater management basins.
10. Utilize Green Infrastructure Standards outlined in NJAC 7:8-5.3 to satisfy groundwater recharge and stormwater runoff quality standards.
11. Analysis will utilize the New Jersey Stormwater Best Management Practices (BMP) Manual as guidance. Overall stormwater management shall take into account the following:
1. Existing site conditions, including: environmentally critical areas; wetlands; flood prone areas; slopes; depth to SHWT; soil type; permeability; texture; drainage area and drainage patterns; and the presence of limestone.
2. Designed to minimize maintenance and ensure proper functioning.
3. Designed, constructed and installed to be strong, durable and corrosion resistant.
4. Designed to meet minimum safety standards.

B. Design and Performance Standards

1. Erosion Control

The minimum design and performance standards for erosion control are those established under the Soil Erosion and Sediment Control Act, N.J.S.A. 4:24-39 et seq. and implementing rules.

2. Groundwater Recharge

The minimum design and performance standards for groundwater recharge require compliance with either of the following:

• a.Demonstrate through hydrologic and hydraulic analysis that the site and its stormwater management measures maintain 100 percent of the average annual pre-construction groundwater recharge volume for the site.
• b.Demonstrate through hydrologic and hydraulic analysis that the increase of stormwater runoff volume from pre-construction to post-construction for the two-year storm is infiltrated.

3. Runoff Quantity

In order to control stormwater runoff quantity impacts one of the following must be demonstrated:

• a.Demonstrate through hydrologic and hydraulic analysis that for stormwater leaving the site, post-construction runoff hydrographs for the 2, 10 and 100-year storm events do not exceed, at any point in time, the pre-construction runoff hydrographs for the same storm events;
• b.Demonstrate through hydrologic and hydraulic analysis that there is no increase, as compared to the pre-construction condition, in the peak runoff rates of stormwater leaving the site for the 2, 10 and 100-year storm events and that the increase volume or change in timing of stormwater runoff will not increase flood damage at or downstream of the site. This analysis shall include the analysis of impacts of

existing land uses and projected land uses assuming full development under existing zoning and land use ordinances in the drainage area;

• c.Design stormwater management measures so that the post-construction peak runoff rates for the 2, 10 and 100-year storm events are 50, 75 and 80 percent, respectively, of the pre-construction peak runoff rates. The percentages apply only to the post-construction stormwater runoff that is attributable to the portion of the site on which the proposed development or project is to be constructed.
• Water Quality

Stormwater management measures shall be designed to reduce the post-construction load of total suspended solids (TSS) in stormwater runoff generated from the water quality design storm by 95 percent of the anticipated load from the development site expressed as an annual average, since the site is located within the watershed of a Category One Waterway.

Direct run-off from building roof tops is not considered contaminated since it has not contacted the pavement or the ground surface, and is not subject to satisfaction of the TSS removal criteria.

IV METHODOLOGY

The overall design will control stormwater runoff and pollutants closer to their source while providing site design measures that can significantly reduce the overall impact of land development on stormwater runoff as required by the Stormwater Management Rules. The methodology typically used to estimate the stormwater runoff peak flows and volumes for the required storm events is the 24-hour storm using the rainfall distribution recommended by the U.S. Department of Agriculture Soil Conservation Service as defined in Technical Release - 55 (TR-55) dated June 1986. The time of concentrations utilized will be calculated for each contributory area utilizing the TR-55 methodology. For the purpose of calculating runoff coefficients and groundwater recharge, a preconstruction condition of a site or portion thereof are assumed to be in good condition. A runoff coefficient or a groundwater recharge land cover for an existing condition may be used on all or a portion of the site if the hydrologic condition has existed on the site or portion of the site for at least five years without interruption prior to the time of application. The runoff computations shall account for all significant land features and structures, such as ponds, wetlands, depressions, hedgerows, or culverts, that may reduce pre-construction stormwater runoff rates and volumes. In computing stormwater runoff from all design storms, the computations consider the relative stormwater runoff rates and/or volumes of pervious and impervious surfaces separately to accurately compute the rates and volume of stormwater runoff from the site. The water quality design storm is 1.25 inches of rainfall in two hours. Water quality calculations shall take into account the distribution of rain from the water quality design storm, as reflected in the Stormwater Rules. All hydrologic and flood routing computations will utilize the HydroCad Stormwater

Modeling Software. The stormwater drainage collection system will be designed in accordance with RSIS standards. The Rational Formula was used to compute peak runoff rates for design of the proposed internal collection system. A 10 year frequency storm was used for design as required by RSIS and the rainfall intensities were obtained from the NJDEP Rainfall Intensity Curves. The sub-areas tributary to each inlet are shown on the Drainage Area Plans. Soil erosion and sediment controls will also be employed as required by the "Standards for Soil Erosion and Sediment Control in New Jersey."

Copies of the TR-55 hydrologic computations, detention basin routings, and Rational Formula computations are contained within the appendices of this report.

V STORMWATER MANAGEMENT PLAN

Erosion Control

The project complies with the "New Jersey Standards for Soil Erosion and Sediment Control". Certification for the project is required from the Ocean County Soil Conservation District.

Groundwater Recharge

All increased run-off from the 2 year storm event will recharge the groundwater through the stormwater management system. In accordance with the NJ Stormwater Management Rules, NJAC 7:8-5.4, the project shall maintain 100 percent of the average annual pre-construction groundwater recharge volume for the site, or demonstrate that the increase of stormwater run-off from pre-construction to post-construction for the two year storm is infiltrated.

As shown in the flood routings, the site will not produce any additional run-off during the 2 year storm event, and will provide for full recharge from any additional impervious surfaces. All run-off generated will be infiltrated on site through the rain garden/bio-retention facility and small scale infiltration basin. Since the design provides groundwater recharge of increased run-off from the 2 year storm event, the design complies with the applicable standard.

Runoff Quantity

Analysis of pre-developed conditions confirms that run-off from the project site is directed to the east property line.

The stormwater management plan consists of on-site collection system and a series of small-scale infiltration basins (SSIB), both surface and sub-surface. Pre-treatment

forebay is provided for the surface SSIB's to provide water quality and TSS removal in accordance with adopted regulations. The overall system will maintain peak discharge rates to less than those required by State adopted Stormwater Management criteria. The following is a summary of the runoff from the site:

A. Pre-developed Conditions

C. Post-developed Conditions

Post-developed run-off rates are tabulated as follows:

Water Quality and Green Infrastructure

The project will allow for full infiltration from all run-off resulting from the Water Quality Design Storm. Accordingly, the project satisfies the requirement for water quality. The project complies with the applicable standards.

Green Infrastructure is complied with by using small-scale infiltration basins with pre-treatment forebay, and with direct contributory area to any component is limited to 2.5 acres (which is not required to include the component itself), and tabulated as follows:

Maintenance

All components of the stormwater management system will be owned and maintained by the land owner. Refer to the Stormwater System Maintenance Plan for additional information.

Time to Drain

Time to drain for each SSIB is tabulated as follows:

APPENDIX A PRE-DEVELOPED CONDITION CALCULATIONS

Routing Diagram for PRE DEV Prepared by Professional Design Services, Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC

PRE DEV

Prepared by Professional Design Services Printed 12/31/2025

HydroCAD\circledR 10.20-6a s/n 02223\circledC 2024 HydroCAD Software Solutions LLC Page 2

Rainfall Events Listing

• 1 2 YEAR NOAA 24-hr D Default 24.00 1 3.42
• 2 10 YEAR NOAA 24-hr D Default 24.00 1 5.38
• 3 100 YEAR NOAA 24-hr D Default 24.00 1 9.48

Area Listing (all nodes)

Soil Listing (all nodes)

PRE DEV

Prepared by Professional Design Services Printed 12/31/2025

HydroCAD\circledR 10.20-6a s/n 02223\circledC 2024 HydroCAD Software Solutions LLC Page 5

PRE DEV NOAA 24-hr D 2 YEAR Rainfall=3.42" Prepared by Professional Design Services Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 6

Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method

Subcatchment1S: POROUS Runoff Area=1.970 ac 0.00% Impervious Runoff Depth>0.08" Flow Length=430' Tc=19.1 min CN=47 Runoff=0.03 cfs 0.012 af Subcatchment2S: IMPERVIOUS Runoff Area=0.450 ac 66.67% Impervious Runoff Depth>2.84" Flow Length=280' Tc=2.6 min CN=97 Runoff=1.43 cfs 0.106 af Reach 3R: COMPOSITE Inflow=1.43 cfs 0.119 af Outflow=1.43 cfs 0.119 af Total Runoff Area = 2.420 ac Runoff Volume = 0.119 af Average Runoff Depth = 0.59" 87.60% Pervious = 2.120 ac 12.40% Impervious = 0.300 ac

Summary for Subcatchment 1S: POROUS

Runoff = 0.03 cfs @ 14.19 hrs, Volume= 0.012 af, Depth> 0.08" Routed to Reach 3R : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

1.080 30 Woods, Good, HSG A

0.110 39 >75% Grass cover, Good, HSG A

0.780 72 Dirt roads, HSG A

1.970 47 Weighted Average

1.970 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

2.5 140 0.0350 0.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps

1.6 190 0.0150 1.97 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps

19.1 430 Total

15.0 100 0.0450 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.42"

Subcatchment 1S: POROUS

Summary for Subcatchment 2S: IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 1.43 cfs @ 12.10 hrs, Volume= 0.106 af, Depth> 2.84" Routed to Reach 3R : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

0.150 96 Gravel surface, HSG A

0.300 98 Paved parking, HSG A

0.450 97 Weighted Average

0.150 33.33% Pervious Area

0.300 66.67% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

1.4 180 0.0110 2.13 Shallow Concentrated Flow, Paved Kv= 20.3 fps

2.6 280 Total

1.2 100 0.0200 1.42 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

Subcatchment 2S: IMPERVIOUS

Summary for Reach 3R: COMPOSITE

[40] Hint: Not Described (Outflow=Inflow)

Inflow Area = 2.420 ac, 12.40% Impervious, Inflow Depth > 0.59" for 2 YEAR event Inflow = 1.43 cfs @ 12.10 hrs, Volume= 0.119 af Outflow = 1.43 cfs @ 12.10 hrs, Volume= 0.119 af, Atten=0%, Lag=0.0 min

Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs

Reach 3R: COMPOSITE

PRE DEV NOAA 24-hr D 10 YEAR Rainfall=5.38" Prepared by Professional Design Services Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 10

Prepared by Professional Design Services HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Printed 12/31/2025 Page 10 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: POROUS Flow Length=430' Tc=19.1 min CN=47 Runoff=0.40 cfs 0.092 af Subcatchment2S: IMPERVIOUS Flow Length=280' Tc=2.6 min CN=97 Runoff=2.28 cfs 0.172 af Reach 3R: COMPOSITE Total Runoff Area = 2.420 ac Runoff Volume = 0.264 af Average Runoff Depth = 1.31' 87.60% Pervious = 2.120 ac 12.40% Impervious = 0.300 ac

Summary for Subcatchment 1S: POROUS

Runoff = 0.40 cfs @ 12.53 hrs, Volume= 0.092 af, Depth> 0.56" Routed to Reach 3R : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

1.080 30 Woods, Good, HSG A

0.110 39 >75% Grass cover, Good, HSG A

0.780 72 Dirt roads, HSG A

1.970 47 Weighted Average

1.970 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

2.5 140 0.0350 0.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps

1.6 190 0.0150 1.97 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps

19.1 430 Total

15.0 100 0.0450 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.42"

Subcatchment 1S: POROUS

Summary for Subcatchment 2S: IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 2.28 cfs @ 12.10 hrs, Volume= 0.172 af, Depth> 4.59" Routed to Reach 3R : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

0.150 96 Gravel surface, HSG A

0.300 98 Paved parking, HSG A

0.450 97 Weighted Average

0.150 33.33% Pervious Area

0.300 66.67% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

1.4 180 0.0110 2.13 Shallow Concentrated Flow, Paved Kv= 20.3 fps

2.6 280 Total

1.2 100 0.0200 1.42 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

Subcatchment 2S: IMPERVIOUS

Summary for Reach 3R: COMPOSITE

[40] Hint: Not Described (Outflow=Inflow)

Inflow Area = 2.420 ac, 12.40% Impervious, Inflow Depth > 1.31" for 10 YEAR event Inflow = 2.32 cfs @ 12.10 hrs, Volume= 0.264 af Outflow = 2.32 cfs @ 12.10 hrs, Volume= 0.264 af, Atten=0%, Lag=0.0 min

Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs

Reach 3R: COMPOSITE

PRE DEV NOAA 24-hr D 100 YEAR Rainfall=9.48" Prepared by Professional Design Services Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 14

Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: POROUS Flow Length=430' Tc=19.1 min CN=47 Runoff=2.68 cfs 0.406 af Subcatchment2S: IMPERVIOUS Flow Length=280' Tc=2.6 min CN=97 Runoff=4.05 cfs 0.309 af Reach 3R: COMPOSITE

Subcatchment1S: POROUS Runoff Area=1.970 ac 0.00% Impervious Runoff Depth>2.47" Flow Length=430' Tc=19.1 min CN=47 Runoff=2.68 cfs 0.406 af Subcatchment2S: IMPERVIOUS Runoff Area=0.450 ac 66.67% Impervious Runoff Depth>8.24" Flow Length=280' Tc=2.6 min CN=97 Runoff=4.05 cfs 0.309 af Reach 3R: COMPOSITE Inflow=5.23 cfs 0.715 af Outflow=5.23 cfs 0.715 af Total Runoff Area = 2.420 ac Runoff Volume = 0.715 af Average Runoff Depth = 3.55" 87.60% Pervious = 2.120 ac 12.40% Impervious = 0.300 ac

Summary for Subcatchment 1S: POROUS

Runoff = 2.68 cfs @ 12.35 hrs, Volume= 0.406 af, Depth> 2.47" Routed to Reach 3R : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 100 YEAR Rainfall=9.48"

Area (ac) CN Description

1.080 30 Woods, Good, HSG A

0.110 39 >75% Grass cover, Good, HSG A

0.780 72 Dirt roads, HSG A

1.970 47 Weighted Average

1.970 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

2.5 140 0.0350 0.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps

1.6 190 0.0150 1.97 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps

19.1 430 Total

15.0 100 0.0450 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.42"

Subcatchment 1S: POROUS

Summary for Subcatchment 2S: IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 4.05 cfs @ 12.10 hrs, Volume= 0.309 af, Depth> 8.24" Routed to Reach 3R : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 100 YEAR Rainfall=9.48"

Area (ac) CN Description

0.150 96 Gravel surface, HSG A

0.300 98 Paved parking, HSG A

0.450 97 Weighted Average

0.150 33.33% Pervious Area

0.300 66.67% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

1.4 180 0.0110 2.13 Shallow Concentrated Flow, Paved Kv= 20.3 fps

2.6 280 Total

1.2 100 0.0200 1.42 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

Subcatchment 2S: IMPERVIOUS

Summary for Reach 3R: COMPOSITE

[40] Hint: Not Described (Outflow=Inflow)

Inflow Area = 2.420 ac, 12.40% Impervious, Inflow Depth > 3.55" for 100 YEAR event Inflow = 5.23 cfs @ 12.11 hrs, Volume= 0.715 af Outflow = 5.23 cfs @ 12.11 hrs, Volume= 0.715 af, Atten=0%, Lag=0.0 min

Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs

Reach 3R: COMPOSITE

APPENDIX B POST-DEVELOPED CONDITION CALCULATIONS

Routing Diagram for POST DEV Prepared by Professional Design Services, Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC

POST DEV

Prepared by Professional Design Services Printed 12/31/2025

HydroCAD\circledR 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 2

Rainfall Events Listing

Rainfall Events Listing

• 1 2 YEAR NOAA 24-hr D Default 24.00 1 3.42
• 2 10 YEAR NOAA 24-hr D Default 24.00 1 5.38
• 3 25 year NOAA 24-hr D Default 24.00 1 6.68
• 4 100 YEAR NOAA 24-hr D Default 24.00 1 9.48

Area Listing (all nodes)

Soil Listing (all nodes)

POST DEV

Prepared by Professional Design Services Printed 12/31/2025

HydroCAD\circledR 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 5

POST DEV NOAA 24-hr D 2 YEAR Rainfall=3.42" Prepared by Professional Design Services Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 6

Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method

Subcatchment1S: POROUS

Subcatchment1S: POROUS Runoff Area=0.570 ac 0.00% Impervious Runoff Depth>0.00" Flow Length=310' Tc=12.9 min CN=39 Runoff=0.00 cfs 0.000 af

Runoff Area=0.720 ac 100.00% Impervious Runoff Depth>2.91"

Subcatchment2S: IMPERVIOUS

Runoff Area=0.720 ac 100.00% Impervious Runoff Depth>2.91" Flow Length=310' Tc=13.1 min CN=98 Runoff=1.36 cfs 0.175 af

Subcatchment5S: IMPERVIOUS Runoff Area=0.270 ac 100.00% Impervious Runoff Depth>2.92" Flow Length=180' Slope=0.0100'/' Tc=1.6 min CN=98 Runoff=0.93 cfs 0.066 af

Subcatchment6S: POROUS

Subcatchment6S: POROUS Runoff Area=0.190 ac 0.00% Impervious Runoff Depth>0.00"

Flow Length=250' Tc=12.4 min CN=39 Runoff=0.00 cfs 0.000 af

Subcatchment8S: PROP WAREHOUSE Runoff Area=0.460 ac 100.00% Impervious Runoff Depth>2.92" Flow Length=280' Slope=0.0100'/' Tc=2.6 min CN=98 Runoff=1.48 cfs 0.112 af

Runoff Area=0.060 ac 0.00% Impervious Runoff Depth>0.00" Tc=2.0 min CN=39 Runoff=0.00 cfs 0.000 af

Subcatchment10S: BY-PASS POROUS

Runoff Area=0.070 ac 100.00% Impervious Runoff Depth>2.92" Tc=2.0 min CN=98 Runoff=0.24 cfs 0.017 af

Subcatchment11S: BY-PASS

Inflow=0.24 cfs 0.040 af

Outflow=0.24 cfs 0.040 af

Reach 10: COMPOSITE

Pond 3P: SSIB #1 SURFACE BASIN Peak Elevation=111.65' Storage=3,983 cfs Inflow=1.36 cfs 0.175 af Discarded=0.09 cfs 0.081 af Primary=0.19 cfs 0.023 af Outflow=0.28 cfs 0.104 af

Pond 8P: SSIB #2 UNDERGROUND Peak Elev=108.37' Storage=0.025 af Inflow=0.93 cfs 0.066 af

Discarded=0.09 cfs 0.065 af Primary=0.00 cfs 0.000 af Outflow=0.09 cfs 0.065 af

Pond 9P: SSIB #3 UNDERGROUND Peak Elev=111.92' Storage=0.047 af Inflow=1.48 cfs 0.112 af Discarded=0.12 cfs 0.102 af Primary=0.00 cfs 0.000 af Outflow=0.12 cfs 0.102 af

Total Runoff Area = 2.340 ac Runoff Volume = 0.369 af Average Runoff Depth = 1.89" 35.04% Pervious = 0.820 ac 64.96% Impervious = 1.520 ac

Summary for Subcatchment 1S: POROUS

[73] Warning: Peak may fall outside time span

Runoff = 0.00 cfs @ 20.00 hrs, Volume= 0.000 af, Depth> 0.00" Routed to Pond 3P : SSIB #1 SURFACE BASIN

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

0.570 39 >75% Grass cover, Good, HSG A

0.570 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.7 100 0.0300 0.14 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps

0.3 50 0.0350 2.81

0.9 160 3.00 Direct Entry, PIPE FLOW

12.9 310 Total

Subcatchment 1S: POROUS

Summary for Subcatchment 2S: IMPERVIOUS

Runoff = 1.36 cfs @ 12.22 hrs, Volume= 0.175 af, Depth> 2.91" Routed to Pond 3P : SSIB #1 SURFACE BASIN

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

0.720 98 Paved parking, HSG A

0.720 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.7 100 0.0300 0.14 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps

0.5 50 0.0110 1.57

0.9 160 3.00 Direct Entry, PIPE FLOW

13.1 310 Total

Subcatchment 2S: IMPERVIOUS

Summary for Subcatchment 5S: IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 0.93 cfs @ 12.08 hrs, Volume= 0.066 af, Depth> 2.92" Routed to Pond 8P : SSIB #2 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

0.270 98 Roofs, HSG A

0.270 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

0.9 50 0.0100 0.94 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

0.7 130 3.00 Direct Entry, PIPE FLOW

1.6 180 Total

Subcatchment 5S: IMPERVIOUS

Summary for Subcatchment 6S: POROUS

[73] Warning: Peak may fall outside time span

Runoff = 0.00 cfs @ 20.00 hrs, Volume= 0.000 af, Depth> 0.00" Routed to Pond 8P : SSIB #2 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

0.190 39 >75% Grass cover, Good, HSG A

0.190 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.3 90 0.0270 0.13 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Paved Kv= 20.3 fps

1.1 160 0.0150 2.49

12.4 250 Total

Subcatchment 6S: POROUS

Summary for Subcatchment 8S: PROP WAREHOUSE BLDG

[49] Hint: Tc<2dt may require smaller dt

Runoff = 1.48 cfs @ 12.10 hrs, Volume= 0.112 af, Depth> 2.92" Routed to Pond 9P : SSIB #3 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

0.460 98 Roofs, HSG A

0.460 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

1.5 100 0.0100 1.08 Sheet Flow,

0.3 40 0.0100 2.03 Smooth surfaces n= 0.011 P2= 3.42"

0.8 140 3.00 Shallow Concentrated Flow, Paved Kv= 20.3 fps

Direct Entry, PIPE FLOW

2.6 280 Total

Subcatchment 8S: PROP WAREHOUSE BLDG

Summary for Subcatchment 10S: BY-PASS POROUS

[49] Hint: Tc<2dt may require smaller dt

[73] Warning: Peak may fall outside time span

Runoff = 0.00 cfs @ 20.00 hrs, Volume= 0.000 af, Depth> 0.00" Routed to Reach 10 : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Subcatchment 10S: BY-PASS POROUS

Summary for Subcatchment 11S: BY-PASS IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 0.24 cfs @ 12.09 hrs, Volume= 0.017 af, Depth> 2.92" Routed to Reach 10 : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2 YEAR Rainfall=3.42"

Area (ac) CN Description

0.070 98 Paved parking, HSG A

0.070 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec)

Direct Entry,

Subcatchment 11S: BY-PASS IMPERVIOUS

Summary for Reach 10: COMPOSITE

[40] Hint: Not Described (Outflow=Inflow)

Inflow Area = 2.340 ac, 64.96% Impervious, Inflow Depth > 0.21" for 2 YEAR event Inflow = 0.24 cfs @ 12.09 hrs, Volume= 0.040 af Outflow = 0.24 cfs @ 12.09 hrs, Volume= 0.040 af, Atten=0%, Lag=0.0 min

Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs

Reach 10: COMPOSITE

Summary for Pond 3P: SSIB #1 SURFACE BASIN

[82] Warning: Early inflow requires earlier time span

Inflow Area = 1.290 ac, 55.81% Impervious, Inflow Depth > 1.63" for 2 YEAR event Inflow = 1.36 cfs @ 12.22 hrs, Volume= 0.175 af Outflow = 0.28 cfs @ 13.18 hrs, Volume= 0.104 af, Atten= 79%, Lag= 57.6 min Discarded = 0.09 cfs @ 13.18 hrs, Volume= 0.081 af Primary = 0.19 cfs @ 13.18 hrs, Volume= 0.023 af Routed to Reach 10 : COMPOSITE Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 111.65' @ 13.18 hrs Surf.Area= 2,939 sf Storage= 3,983 cf Plug-Flow detention time= 167.6 min calculated for 0.104 af (59% of inflow) Center-of-Mass det. time= 81.6 min ( 831.1 - 749.5 )

Discarded OutFlow Max=0.09 cfs @ 13.18 hrs HW=111.65' (Free Discharge) 1=Exfiltration (Controls 0.09 cfs)

Primary OutFlow Max=0.19 cfs @ 13.18 hrs HW=111.65' (Free Discharge) 2=Orifice/Grate (Orifice Controls 0.19 cfs @ 1.25 fps) 3=Orifice/Grate (Controls 0.00 cfs)

Pond 3P: SSIB #1 SURFACE BASIN

Stage-Discharge for Pond 3P: SSIB #1 SURFACE BASIN

Stage-Area-Storage for Pond 3P: SSIB #1 SURFACE BASIN

Summary for Pond 8P: SSIB #2 UNDERGROUND

[82] Warning: Early inflow requires earlier time span

Inflow Area = 0.460 ac, 58.70% Impervious, Inflow Depth > 1.71" for 2 YEAR event Inflow = 0.93 cfs @ 12.08 hrs, Volume= 0.066 af Outflow = 0.09 cfs @ 12.99 hrs, Volume= 0.065 af, Atten= 91%, Lag= 54.4 min Discarded = 0.09 cfs @ 12.99 hrs, Volume= 0.065 af Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routed to Reach 10: COMPOSITE Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 108.37' @ 12.99 hrs Surf.Area= 0.064 ac Storage= 0.025 af Plug-Flow detention time= 100.6 min calculated for 0.065 af (99% of inflow) Center-of-Mass det. time= 98.8 min (834.8 - 736.1)

0.105 af Total Available Storage

Storage Group A created with Chamber Wizard

Pond 8P: SSIB #2 UNDERGROUND - Chamber Wizard Field A

Chamber Model = ADS N-12 24" (ADS N-12® Pipe) Inside= 23.8"W x 23.8"H => 3.10 sf x 20.00'L = 62.0 cf Outside= 28.0"W x 28.0"H => 3.92 sf x 20.00'L = 78.4 cf 28.0" Wide + 13.4" Spacing = 41.4" C-C Row Spacing 3 Chambers/Row x 20.00' Long +2.33' Header x 2 = 64.67' Row Length +10.0" End Stone x 2 = 66.33' Base Length 12 Rows x 28.0" Wide + 13.4" Spacing x 11 + 10.0" Side Stone x 2 = 41.95' Base Width 4.0" Stone Base + 28.0" Chamber Height + 4.0" Stone Cover = 3.00' Field Height 36 Chambers x 62.0 cf + 40.28' Header x 3.10 sf x 2 = 2,481.8 cf Chamber Storage 36 Chambers x 78.4 cf + 40.28' Header x 3.92 sf x 2 = 3,137.9 cf Displacement 8,348.3 cf Field - 3,137.9 cf Chambers = 5,210.4 cf Stone x 40.0% Voids = 2,084.2 cf Stone Storage Chamber Storage + Stone Storage = 4,565.9 cf = 0.105 af Overall Storage Efficiency = 54.7% Overall System Size = 66.33' x 41.95' x 3.00'

36 Chambers 309.2 cy Field 193.0 cy Stone

0101010101010101010

Pond 8P: SSIB #2 UNDERGROUND

Stage-Discharge for Pond 8P: SSIB #2 UNDERGROUND

Stage-Area-Storage for Pond 8P: SSIB #2 UNDERGROUND

Summary for Pond 9P: SSIB #3 UNDERGROUND

[82] Warning: Early inflow requires earlier time span

Inflow Area = 0.460 ac, 100.00% Impervious, Inflow Depth > 2.92" for 2 YEAR event Inflow = 1.48 cfs @ 12.10 hrs, Volume= 0.112 af Outflow = 0.12 cfs @ 13.25 hrs, Volume= 0.102 af, Atten= 92%, Lag= 69.2 min Discarded = 0.12 cfs @ 13.25 hrs, Volume= 0.102 af Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routed to Reach 10: COMPOSITE Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 111.92' @ 13.25 hrs Surf.Area= 0.085 ac Storage= 0.047 af Plug-Flow detention time= 144.1 min calculated for 0.101 af (91% of inflow) Center-of-Mass det. time= 111.3 min (848.5 - 737.2)

0.139 af Total Available Storage

Storage Group A created with Chamber Wizard

Pond 9P: SSIB #3 UNDERGROUND - Chamber Wizard Field A

Chamber Model = ADS N-12 24" (ADS N-12® Pipe) Inside= 23.8"W x 23.8"H => 3.10 sf x 20.00'L = 62.0 cf Outside= 28.0"W x 28.0"H => 3.92 sf x 20.00'L = 78.4 cf 28.0" Wide + 13.4" Spacing = 41.4" C-C Row Spacing 3 Chambers/Row x 20.00' Long +2.33' Header x 2 = 64.67' Row Length +10.0" End Stone x 2 = 66.33' Base Length 16 Rows x 28.0" Wide + 13.4" Spacing x 15 + 10.0" Side Stone x 2 = 55.75' Base Width 4.0" Stone Base + 28.0" Chamber Height + 4.0" Stone Cover = 3.00' Field Height 48 Chambers x 62.0 cf + 54.08' Header x 3.10 sf x 2 = 3,311.3 cf Chamber Storage 48 Chambers x 78.4 cf + 54.08' Header x 3.92 sf x 2 = 4,186.8 cf Displacement 11,094.6 cf Field - 4,186.8 cf Chambers = 6,907.8 cf Stone x 40.0% Voids = 2,763.1 cf Stone Storage Chamber Storage + Stone Storage = 6,074.4 cf = 0.139 af Overall Storage Efficiency = 54.8% Overall System Size = 66.33' x 55.75' x 3.00'

48 Chambers 410.9 cy Field 255.8 cy Stone

101010

Pond 9P: SSIB #3 UNDERGROUND

Stage-Discharge for Pond 9P: SSIB #3 UNDERGROUND

Stage-Area-Storage for Pond 9P: SSIB #3 UNDERGROUND

POST DEV NOAA 24-hr D 10 YEAR Rainfall=5.38" Prepared by Professional Design Services Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 29

Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method

Subcatchment1S: POROUS

Subcatchment1S: POROUS Runoff Area=0.570 ac 0.00% Impervious Runoff Depth>0.21" Flow Length=310' Tc=12.9 min CN=39 Runoff=0.03 cfs 0.010 af

Subcatchment2S: IMPERVIOUS

Subcatchment2S: IMPERVIOUS Runoff Area=0.720 ac 100.00% Impervious Runoff Depth>4.66" Flow Length=310' Tc=13.1 min CN=98 Runoff=2.16 cfs 0.280 af

Subcatchment5S: IMPERVIOUS Runoff Area=0.270 ac 100.00% Impervious Runoff Depth>4.66" Flow Length=180' Slope=0.0100'/' Tc=1.6 min CN=98 Runoff=1.48 cfs 0.105 af

Runoff Area=0.190 ac 0.00% Impervious Runoff Depth>0.22" Flow Length=250' Tc=12.4 min CN=39 Runoff=0.01 cfs 0.003 af

Subcatchment6S: POROUS

Subcatchment8S: PROP WAREHOUSE Runoff Area=0.460 ac 100.00% Impervious Runoff Depth>4.66" Flow Length=280' Slope=0.0100'/' Tc=2.6 min CN=98 Runoff=2.35 cfs 0.179 af

Subcatchment10S: BY-PASSPOROUS Runoff Area=0.060 ac 0.00% Impervious Runoff Depth>0.22" Tc=2.0 min CN=39 Runoff=0.00 cfs 0.001 af

Runoff Area=0.070 ac 100.00% Impervious Runoff Depth>4.66" Tc=2.0 min CN=98 Runoff=0.37 cfs 0.027 af

Subcatchment11S: BY-PASS

Inflow=1.00 cfs 0.149 af Outflow=1.00 cfs 0.149 af

Reach 10: COMPOSITE

Pond 3P: SSIB #1 SURFACE BASIN Peak Elev= $ 112.02' $ Storage=5,118 cf Inflow= $ 2.16 $ cfs 0.290 af Discarded=0.10 cfs 0.089 af Primary=0.95 cfs 0.120 af Outflow=1.05 cfs 0.209 af

Pond 8P: SSIB #2 UNDERGROUND Peak Elev=108.89' Storage=0.047 af Inflow=1.48 cfs 0.108 af

Discarded=0.10 cfs 0.088 af Primary=0.00 cfs 0.000 af Outflow=0.10 cfs 0.088 af

Pond 9P: SSIB #3 UNDERGROUND Peak Elev=112.59' Storage=0.087 af Inflow=2.35 cfs 0.179 af Discarded=0.14 cfs 0.127 af Primary=0.00 cfs 0.000 af Outflow=0.14 cfs 0.127 af

Total Runoff Area = 2.340 ac Runoff Volume = 0.605 af Average Runoff Depth = 3.10" 35.04% Pervious = 0.820 ac 64.96% Impervious = 1.520 ac

Summary for Subcatchment 1S: POROUS

Runoff = 0.03 cfs @ 13.03 hrs, Volume= 0.010 af, Depth> 0.21" Routed to Pond 3P : SSIB #1 SURFACE BASIN

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

0.570 39 >75% Grass cover, Good, HSG A

0.570 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.7 100 0.0300 0.14 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42"

0.3 50 0.0350 2.81 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps

0.9 160 3.00 Direct Entry, PIPE FLOW

12.9 310 Total

Subcatchment 1S: POROUS

Summary for Subcatchment 2S: IMPERVIOUS

Runoff = 2.16 cfs @ 12.22 hrs, Volume=

Runoff = 2.16 cfs @ 12.22 hrs, Volume= Routed to Pond 3P : SSIB #1 SURFACE BASIN 0.280 af, Depth> 4.66"

0.280 af, Depth> 4.66"

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

0.720 98 Paved parking, HSG A

0.720 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.7 100 0.0300 0.14 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps

0.5 50 0.0110 1.57

0.9 160 3.00 Direct Entry, PIPE FLOW

13.1 310 Total

Subcatchment 2S: IMPERVIOUS

Summary for Subcatchment 5S: IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 1.48 cfs @ 12.08 hrs, Volume= 0.105 af, Depth> 4.66" Routed to Pond 8P : SSIB #2 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

0.270 98 Roofs, HSG A

0.270 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

0.9 50 0.0100 0.94 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

0.7 130 3.00 Direct Entry, PIPE FLOW

1.6 180 Total

Subcatchment 5S: IMPERVIOUS

Summary for Subcatchment 6S: POROUS

Runoff = 0.01 cfs @ 13.01 hrs, Volume= 0.003 af, Depth> 0.22" Routed to Pond 8P : SSIB #2 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

0.190 39 >75% Grass cover, Good, HSG A

0.190 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.3 90 0.0270 0.13 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42"

1.1 160 0.0150 2.49 Shallow Concentrated Flow, Paved Kv= 20.3 fps

12.4 250 Total

Subcatchment 6S: POROUS

Summary for Subcatchment 8S: PROP WAREHOUSE BLDG

[49] Hint: Tc<2dt may require smaller dt

Runoff = 2.35 cfs @ 12.10 hrs, Volume= 0.179 af, Depth> 4.66" Routed to Pond 9P : SSIB #3 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

0.460 98 Roofs, HSG A

0.460 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

1.5 100 0.0100 1.08 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

0.3 40 0.0100 2.03 Shallow Concentrated Flow, Paved Kv= 20.3 fps

0.8 140 3.00 Direct Entry, PIPE FLOW

2.6 280 Total

Subcatchment 8S: PROP WAREHOUSE BLDG

Summary for Subcatchment 10S: BY-PASS POROUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 0.00 cfs @ 12.50 hrs, Volume= 0.001 af, Depth> 0.22" Routed to Reach 10 : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Subcatchment 10S: BY-PASS POROUS

Summary for Subcatchment 11S: BY-PASS IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 0.37 cfs @ 12.09 hrs, Volume= 0.027 af, Depth> 4.66" Routed to Reach 10 : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10 YEAR Rainfall=5.38"

Area (ac) CN Description

0.070 98 Paved parking, HSG A

0.070 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec)

Direct Entry,

Subcatchment 11S: BY-PASS IMPERVIOUS

Summary for Reach 10: COMPOSITE

[40] Hint: Not Described (Outflow=Inflow)

Inflow Area = 2.340 ac, 64.96% Impervious, Inflow Depth > 0.76" for 10 YEAR event Inflow = 1.00 cfs @ 12.65 hrs, Volume= 0.149 af Outflow = 1.00 cfs @ 12.65 hrs, Volume= 0.149 af, Atten=0%, Lag=0.0 min

Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs

Reach 10: COMPOSITE

Summary for Pond 3P: SSIB #1 SURFACE BASIN

[82] Warning: Early inflow requires earlier time span

Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 112.02' @ 12.67 hrs Surf.Area= 3,217 sf Storage= 5,118 cf

Plug-Flow detention time = 129.4 min calculated for 0.208 af (72% of inflow) Center-of-Mass det. time = 59.2 min (812.0 - 752.7)

Discarded OutFlow Max=0.10 cfs @ 12.67 hrs HW=112.02' (Free Discharge) 1=Exfiltration (Controls 0.10 cfs)

Primary OutFlow Max=0.95 cfs @ 12.67 hrs HW=112.02' (Free Discharge) 2=Orifice/Grate (Orifice Controls 0.95 cfs @ 2.84 fps) 3=Orifice/Grate (Controls 0.00 cfs)

Pond 3P: SSIB #1 SURFACE BASIN

Stage-Discharge for Pond 3P: SSIB #1 SURFACE BASIN

Stage-Area-Storage for Pond 3P: SSIB #1 SURFACE BASIN

Summary for Pond 8P: SSIB #2 UNDERGROUND

[82] Warning: Early inflow requires earlier time span

Inflow Area = 0.460 ac, 58.70% Impervious, Inflow Depth > 2.83" for 10 YEAR event Inflow = 1.48 cfs @ 12.08 hrs, Volume= 0.108 af Outflow = 0.10 cfs @ 13.45 hrs, Volume= 0.088 af, Atten= 93%, Lag= 82.1 min Discarded = 0.10 cfs @ 13.45 hrs, Volume= 0.088 af Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routed to Reach 10: COMPOSITE Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 108.89' @ 13.45 hrs Surf.Area= 0.064 ac Storage= 0.047 af Plug-Flow detention time= 160.2 min calculated for 0.088 af (81% of inflow) Center-of-Mass det. time= 102.6 min (841.8 - 739.2)

0.105 af Total Available Storage

Storage Group A created with Chamber Wizard

Pond 8P: SSIB #2 UNDERGROUND - Chamber Wizard Field A

Chamber Model = ADS N-12 24" (ADS N-12® Pipe) Inside= 23.8"W x 23.8"H => 3.10 sf x 20.00'L = 62.0 cf Outside= 28.0"W x 28.0"H => 3.92 sf x 20.00'L = 78.4 cf 28.0" Wide + 13.4" Spacing = 41.4" C-C Row Spacing 3 Chambers/Row x 20.00' Long +2.33' Header x 2 = 64.67' Row Length +10.0" End Stone x 2 = 66.33' Base Length 12 Rows x 28.0" Wide + 13.4" Spacing x 11 + 10.0" Side Stone x 2 = 41.95' Base Width 4.0" Stone Base + 28.0" Chamber Height + 4.0" Stone Cover = 3.00' Field Height 36 Chambers x 62.0 cf + 40.28' Header x 3.10 sf x 2 = 2,481.8 cf Chamber Storage 36 Chambers x 78.4 cf + 40.28' Header x 3.92 sf x 2 = 3,137.9 cf Displacement 8,348.3 cf Field - 3,137.9 cf Chambers = 5,210.4 cf Stone x 40.0% Voids = 2,084.2 cf Stone Storage Chamber Storage + Stone Storage = 4,565.9 cf = 0.105 af Overall Storage Efficiency = 54.7% Overall System Size = 66.33' x 41.95' x 3.00'

36 Chambers 309.2 cy Field 193.0 cy Stone

010101

Pond 8P: SSIB #2 UNDERGROUND

Stage-Discharge for Pond 8P: SSIB #2 UNDERGROUND

Stage-Area-Storage for Pond 8P: SSIB #2 UNDERGROUND

Summary for Pond 9P: SSIB #3 UNDERGROUND

[82] Warning: Early inflow requires earlier time span

Inflow Area = 0.460 ac,100.00% Impervious, Inflow Depth > 4.66" for 10 YEAR event Inflow = 2.35 cfs @ 12.10 hrs, Volume= 0.179 af Outflow = 0.14 cfs @ 13.59 hrs, Volume= 0.127 af, Atten= 94%, Lag= 89.8 min Discarded = 0.14 cfs @ 13.59 hrs, Volume= 0.127 af Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routed to Reach 10 : COMPOSITE Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 112.59' @ 13.59 hrs Surf.Area= 0.085 ac Storage= 0.087 af Plug-Flow detention time= 170.1 min calculated for 0.127 af (71% of inflow) Center-of-Mass det. time= 99.5 min ( 833.8 - 734.2 )

0.139 af Total Available Storage

Storage Group A created with Chamber Wizard

Pond 9P: SSIB #3 UNDERGROUND - Chamber Wizard Field A

Chamber Model = ADS N-12 24" (ADS N-12® Pipe) Inside= 23.8"W x 23.8"H => 3.10 sf x 20.00"L = 62.0 cf Outside= 28.0"W x 28.0"H => 3.92 sf x 20.00"L = 78.4 cf 28.0" Wide + 13.4" Spacing = 41.4" C-C Row Spacing 3 Chambers/Row x 20.00' Long +2.33' Header x 2 = 64.67' Row Length +10.0" End Stone x 2 = 66.33' Base Length 16 Rows x 28.0" Wide + 13.4" Spacing x 15 + 10.0" Side Stone x 2 = 55.75' Base Width 4.0" Stone Base + 28.0" Chamber Height + 4.0" Stone Cover = 3.00' Field Height 48 Chambers x 62.0 cf + 54.08' Header x 3.10 sf x 2 = 3,311.3 cf Chamber Storage 48 Chambers x 78.4 cf + 54.08' Header x 3.92 sf x 2 = 4,186.8 cf Displacement 11,094.6 cf Field - 4,186.8 cf Chambers = 6,907.8 cf Stone x 40.0% Voids = 2,763.1 cf Stone Storage Chamber Storage + Stone Storage = 6,074.4 cf = 0.139 af Overall Storage Efficiency = 54.8% Overall System Size = 66.33' x 55.75' x 3.00'

48 Chambers 410.9 cy Field 255.8 cy Stone

101010

Pond 9P: SSIB #3 UNDERGROUND

Stage-Discharge for Pond 9P: SSIB #3 UNDERGROUND

Stage-Area-Storage for Pond 9P: SSIB #3 UNDERGROUND

POST DEV NOAA 24-hr D 25 year Rainfall=6.68" Prepared by Professional Design Services Printed 12/31/2025 HydroCAD® 10.20-6a s/n 02223 © 2024 HydroCAD Software Solutions LLC Page 52

Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method

Subcatchment1S: POROUS

Subcatchment1S: POROUS Runoff Area=0.570 ac 0.00% Impervious Runoff Depth>0.53" Flow Length=310' Tc=12.9 min CN=39 Runoff=0.11 cfs 0.025 af

Subcatchment2S: IMPERVIOUS

Subcatchment2S: IMPERVIOUS Runoff Area=0.720 ac 100.00% Impervious Runoff Depth>5.81" Flow Length=310' Tc=13.1 min CN=98 Runoff=2.68 cfs 0.349 af

Subcatchment5S: IMPERVIOUS Runoff Area=0.270 ac 100.00% Impervious Runoff Depth>5.82" Flow Length=180' Slope=0.0100'/' Tc=1.6 min CN=98 Runoff=1.84 cfs 0.131 af

Runoff Area=0.190 ac 0.00% Impervious Runoff Depth>0.53"

Subcatchment6S: POROUS

Flow Length=250' Tc=12.4 min CN=39 Runoff=0.04 cfs 0.008 af

Subcatchment8S: PROP WAREHOUSE Runoff Area=0.460 ac 100.00% Impervious Runoff Depth>5.82" Flow Length=280' Slope=0.0100'/' Tc=2.6 min CN=98 Runoff=2.92 cfs 0.223 af

Subcatchment10S: BY-PASS POROUS Runoff Area=0.060 ac 0.00% Impervious Runoff Depth>0.54" Tc=2.0 min CN=39 Runoff=0.02 cfs 0.003 af

Subcatchment11S: BY-PASS Runoff Area=0.070 ac 100.00% Impervious Runoff Depth>5.82" Tc=2.0 min CN=98 Runoff=0.46 cfs 0.034 af

Inflow=1.47 cfs 0.252 af

Outflow=1.47 cfs 0.252 af

Reach 10: COMPOSITE

Pond 3P: SSIB #1 SURFACE BASIN Peak Elev= $ 112.33' $ Storage= $ 6,132 $ cf Inflow= $ 2.75 $ cfs 0.374 af Discarded= $ 0.11 $ cfs 0.093 af Primary= $ 1.30 $ cfs 0.199 af Outflow= $ 1.41 $ cfs 0.291 af

Pond 8P: SSIB #2 UNDERGROUND Peak Elev=109.14' Storage=0.059 af Inflow=1.84 cfs 0.139 af

Discarded=0.11 cfs 0.096 af Primary=0.12 cfs 0.012 af Outflow=0.22 cfs 0.108 af

Pond 9P: SSIB #3 UNDERGROUND Peak Elev=113.06' Storage=0.114 af Inflow=2.92 cfs 0.223 af Discarded=0.15 cfs 0.141 af Primary=0.05 cfs 0.004 af Outflow=0.21 cfs 0.146 af

Total Runoff Area = 2.340 ac Runoff Volume = 0.773 af Average Runoff Depth = 3.97" 35.04% Pervious = 0.820 ac 64.96% Impervious = 1.520 ac

Summary for Subcatchment 1S: POROUS

Runoff = 0.11 cfs @ 12.55 hrs, Volume=

Runoff = 0.11 cfs @ 12.55 hrs, Volume= Routed to Pond 3P : SSIB #1 SURFACE BASIN 0.025 af, Depth> 0.53"

0.025 af, Depth> 0.53"

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 25 year Rainfall=6.68"

Area (ac) CN Description

0.570 39 >75% Grass cover, Good, HSG A

0.570 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.7 100 0.0300 0.14 Sheet Flow, Grass: Dense n=0.240 P2=3.42"

0.3 50 0.0350 2.81 Shallow Concentrated Flow, Grassed Waterway Kv=15.0 fps

0.9 160 3.00 Direct Entry, PIPE FLOW

12.9 310 Total

Subcatchment 1S: POROUS

Summary for Subcatchment 2S: IMPERVIOUS

Runoff = 2.68 cfs @ 12.22 hrs, Volume= 0.349 af, Depth> 5.81" Routed to Pond 3P : SSIB #1 SURFACE BASIN

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 25 year Rainfall=6.68"

Area (ac) CN Description

0.720 98 Paved parking, HSG A

0.720 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.7 100 0.0300 0.14 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps

0.5 50 0.0110 1.57

0.9 160 3.00 Direct Entry, PIPE FLOW

13.1 310 Total

Subcatchment 2S: IMPERVIOUS

Summary for Subcatchment 5S: IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 1.84 cfs @ 12.08 hrs, Volume= 0.131 af, Depth> 5.82" Routed to Pond 8P : SSIB #2 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 25 year Rainfall=6.68"

Area (ac) CN Description

0.270 98 Roofs, HSG A

0.270 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

0.9 50 0.0100 0.94 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

0.7 130 3.00 Direct Entry, PIPE FLOW

1.6 180 Total

Subcatchment 5S: IMPERVIOUS

Summary for Subcatchment 6S: POROUS

Runoff = 0.04 cfs @ 12.46 hrs, Volume= 0.008 af, Depth> 0.53" Routed to Pond 8P : SSIB #2 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 25 year Rainfall=6.68"

Area (ac) CN Description

0.190 39 >75% Grass cover, Good, HSG A

0.190 100.00% Pervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

11.3 90 0.0270 0.13 Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Paved Kv= 20.3 fps

1.1 160 0.0150 2.49

12.4 250 Total

Subcatchment 6S: POROUS

Summary for Subcatchment 8S: PROP WAREHOUSE BLDG

[49] Hint: Tc<2dt may require smaller dt

Runoff = 2.92 cfs @ 12.10 hrs, Volume= 0.223 af, Depth> 5.82" Routed to Pond 9P : SSIB #3 UNDERGROUND

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 25 year Rainfall=6.68"

Area (ac) CN Description

0.460 98 Roofs, HSG A

0.460 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description

1.5 100 0.0100 1.08 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"

0.3 40 0.0100 2.03 Shallow Concentrated Flow, Paved Kv= 20.3 fps

0.8 140 3.00 Direct Entry, PIPE FLOW

2.6 280 Total

Subcatchment 8S: PROP WAREHOUSE BLDG

Summary for Subcatchment 10S: BY-PASS POROUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 0.02 cfs @ 12.12 hrs, Volume= 0.003 af, Depth> 0.54" Routed to Reach 10 : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 25 year Rainfall=6.68"

Subcatchment 10S: BY-PASS POROUS

Summary for Subcatchment 11S: BY-PASS IMPERVIOUS

[49] Hint: Tc<2dt may require smaller dt

Runoff = 0.46 cfs @ 12.09 hrs, Volume= 0.034 af, Depth> 5.82" Routed to Reach 10 : COMPOSITE

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 25 year Rainfall=6.68"

Area (ac) CN Description

0.070 98 Paved parking, HSG A

0.070 100.00% Impervious Area

Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec)

Direct Entry,

Subcatchment 11S: BY-PASS IMPERVIOUS

Summary for Reach 10: COMPOSITE

[40] Hint: Not Described (Outflow=Inflow)

Inflow Area = 2.340 ac, 64.96% Impervious, Inflow Depth > 1.29" for 25 year event Inflow = 1.47 cfs @ 12.68 hrs, Volume= 0.252 af Outflow = 1.47 cfs @ 12.68 hrs, Volume= 0.252 af, Atten=0%, Lag=0.0 min

Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs

Reach 10: COMPOSITE

Summary for Pond 3P: SSIB #1 SURFACE BASIN

[82] Warning: Early inflow requires earlier time span

Inflow Area = 1.290 ac, 55.81% Impervious, Inflow Depth > 3.48" for 25 year event Inflow = 2.75 cfs @ 12.23 hrs, Volume= 0.374 af Outflow = 1.41 cfs @ 12.65 hrs, Volume= 0.291 af, Atten=49%, Lag=25.4 min Discarded = 0.11 cfs @ 12.65 hrs, Volume= 0.093 af Primary = 1.30 cfs @ 12.65 hrs, Volume= 0.199 af Routed to Reach 10 : COMPOSITE Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 112.33' @ 12.65 hrs Surf.Area= 3,460 sf Storage= 6,132 cf Plug-Flow detention time= 120.4 min calculated for 0.290 af (78% of inflow) Center-of-Mass det. time= 58.6 min ( 813.8 - 755.2 )

Discarded OutFlow Max=0.11 cfs @ 12.65 hrs HW=112.32' (Free Discharge) 1=Exfiltration (Controls 0.11 cfs)

Primary OutFlow Max=1.30 cfs @ 12.65 hrs HW=112.32' (Free Discharge) 2=Orifice/Grate (Orifice Controls 1.30 cfs @ 3.90 fps) 3=Orifice/Grate (Controls 0.00 cfs)

Pond 3P: SSIB #1 SURFACE BASIN

Stage-Discharge for Pond 3P: SSIB #1 SURFACE BASIN

Stage-Area-Storage for Pond 3P: SSIB #1 SURFACE BASIN

Summary for Pond 8P: SSIB #2 UNDERGROUND

[82] Warning: Early inflow requires earlier time span

Inflow Area = 0.460 ac, 58.70% Impervious, Inflow Depth > 3.64" for 25 year event Inflow = 1.84 cfs @ 12.08 hrs, Volume= 0.139 af Outflow = 0.22 cfs @ 12.88 hrs, Volume= 0.108 af, Atten= 88%, Lag= 47.6 min Discarded = 0.11 cfs @ 12.88 hrs, Volume= 0.096 af Primary = 0.12 cfs @ 12.88 hrs, Volume= 0.012 af Routed to Reach 10 : COMPOSITE Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 109.14' @ 12.88 hrs Surf.Area= 0.064 ac Storage= 0.059 af Plug-Flow detention time= 151.0 min calculated for 0.108 af (77% of inflow) Center-of-Mass det. time= 86.4 min ( 828.2 - 741.8 )

0.105 af Total Available Storage

Storage Group A created with Chamber Wizard

Discarded OutFlow Max=0.11 cfs @ 12.88 hrs HW=109.14' (Free Discharge) 1=Exfiltration (Controls 0.11 cfs)

Primary OutFlow Max=0.12 cfs @ 12.88 hrs HW=109.14' (Free Discharge) 2=Orifice/Grate (Orifice Controls 0.12 cfs @ 1.21 fps)

Pond 8P: SSIB #2 UNDERGROUND - Chamber Wizard Field A

Chamber Model = ADS N-12 24" (ADS N-12® Pipe) Inside= 23.8"W x 23.8"H => 3.10 sf x 20.00'L = 62.0 cf Outside= 28.0"W x 28.0"H => 3.92 sf x 20.00'L = 78.4 cf 28.0" Wide + 13.4" Spacing = 41.4" C-C Row Spacing 3 Chambers/Row x 20.00' Long +2.33' Header x 2 = 64.67' Row Length +10.0" End Stone x 2 = 66.33' Base Length 12 Rows x 28.0" Wide + 13.4" Spacing x 11 + 10.0" Side Stone x 2 = 41.95' Base Width 4.0" Stone Base + 28.0" Chamber Height + 4.0" Stone Cover = 3.00' Field Height 36 Chambers x 62.0 cf + 40.28' Header x 3.10 sf x 2 = 2,481.8 cf Chamber Storage 36 Chambers x 78.4 cf + 40.28' Header x 3.92 sf x 2 = 3,137.9 cf Displacement 8,348.3 cf Field - 3,137.9 cf Chambers = 5,210.4 cf Stone x 40.0% Voids = 2,084.2 cf Stone Storage Chamber Storage + Stone Storage = 4,565.9 cf = 0.105 af Overall Storage Efficiency = 54.7% Overall System Size = 66.33' x 41.95' x 3.00'

36 Chambers 309.2 cy Field 193.0 cy Stone

0101010101010101010

Pond 8P: SSIB #2 UNDERGROUND

Stage-Discharge for Pond 8P: SSIB #2 UNDERGROUND

Stage-Area-Storage for Pond 8P: SSIB #2 UNDERGROUND