ZB 22 13 2023 03 Drainage Statement

DRAINAGE STATEMENT for Orange Dev, LLC Proposed Popeyes Restaurant & Sonic Restaurant 470 Eagle Rock Avenue (CR 611) Block 153, Lot 38 Township of West Orange Essex County, NJ Prepared by: 1904 Main Street Lake Como, NJ 07719 (732) 974-0198 Matthew J. Bersch, PE NJ Professional Engineer License #54522 October 2022 Last Revised March 2023 DEC# 1021-99-025

TABLE OF CONTENTS Page No. I. Drainage Summary .................................................................................... 3 APPENDIX • Location Map • USGS Map • NRCS Web Soil Survey • Time of Concentration (Tc) Calculations • Runoff Curve Number (CN) Calculations – Existing • Runoff Curve Number (CN) Calculations – Proposed • Hydrograph Summary Reports – Existing and Proposed Conditions 2 yr. 10 yr. & 100 yr. • Multi-Hydrograph Plot – Existing and Proposed Conditions Superimposed 2 yr. 10 yr. & 100 yr. • Stormwater Collection System Calculations (Pipe Sizing) • Drainage & Inlet Area Maps Orange Dev, LLC October 2022 DEC# 1021-99-025 2 Last Revised March 2023

I. Drainage Statement This Drainage Statement has been prepared to define and analyze the stormwater drainage conditions that would occur as a result of the improvements to Block 153, Lot 38, as shown on the Township of West Orange Tax Map Sheet No. 84, located in the Township of West Orange, Essex County, New Jersey. In existing conditions, the subject site consists of 0.94 acres (40,971 SF) and is located at 470 Eagle Rock Avenue. Under existing conditions, the site is developed as a restaurant with associated parking, landscaping and lighting. The existing development has an impervious coverage of 88.3% (36,177 SF) and is located in the B-2 – General Business Zone. The proposed development consists of the demolition of the existing restaurant and the construction of a 2,525 SF Popeyes restaurant with a drive-thru and a 1,616 SF Sonic restaurant with a drive-thru. Additional site amenities include parking, landscaping, lighting and a trash enclosures. As a result of the proposed development, a portion of the previously vacated Fundus Road right-of-way will be incorporated within Lot 38, bringing the total lot area to 1.05 AC (45,713 SF). The proposed development will result in a total impervious coverage of 69.4% (31,732 SF). The stormwater analysis has been conducted to include the vacated Fundus Road right-of-way in both existing and proposed conditions. This results in an existing impervious coverage of approximately 80.5% (36,782 SF). Therefore, the proposed development will result in a decrease in impervious coverage of approximately 11.1% (5,050 SF) and a decrease in motor vehicle surface area of approximately 4,600 SF. In addition, per the Natural Resources Conservation Service Web Soil Survey, a portion of the property is located within unclassified Urban Land soil. To be conservative, the analysis utilized HSG B in existing conditions and HSG D in proposed. Based upon the fact that the proposed improvements will result in more than one (1) acre of land disturbance, this project is classified as a “major development” and is subject to compliance with the Stormwater Regulations set forth in NJAC 7:8. However, the proposed project is reducing motor vehicle surface area and impervious coverage from existing to proposed conditions. As such, per NJAC 7:8-5.5, the project is not required to meet the stormwater runoff quality standards as the

g motor vehicle surface area and impervious coverage from existing to proposed conditions. As such, per NJAC 7:8-5.5, the project is not required to meet the stormwater runoff quality standards as the motor vehicle surface area onsite will not be increased by more than ¼ acre from existing to proposed conditions. As a result, the site has been designed to meet the stormwater runoff quantity and groundwater recharge standards set forth by the Township of West Orange Land Development Ordinance and NJAC 7:8. Per NJAC 7:8- 5.6(b).1, the stormwater runoff quantity requirements are met through demonstration that the 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. Per NJAC 7:8-5.4(b).1.i, the groundwater recharge requirements are met through demonstration that greater than one hundred (100) percent of the average annual pre-construction groundwater recharge volume for the site is being maintained, due to the reduction in impervious coverage as a result of the proposed development. Orange Dev, LLC October 2022 DEC# 1021-99-025 3 Last Revised March 2023

In existing conditions, a majority of the stormwater runoff from the area to be disturbed is conveyed via overland flow to the proposed onsite inlets which connect to the existing stormwater infrastructure within Rosney Terrace. Stormwater runoff from Rosney Terrace ultimately discharges into the existing stormwater infrastructure within Eagle Rock Avenue. The remaining stormwater runoff from the site discharges directly to the existing inlet along Eagle Rock Avenue via overland flow. As such, one point of analysis can be considered for the overall development. Stormwater runoff resulting from the proposed improvements has been designed to maintain existing drainage patterns. Six (6) additional inlets are proposed within the site to assist in collecting stormwater runoff from impervious areas, which are routed via 12” reinforced concrete pipes to the existing inlet within Rosney Terrace. Due to the reduction in impervious coverage, the volume and peak discharge runoff rates for the 2-, 10- & 100-year design storms have been reduced. As such, there shall be no adverse impacts to the properties located upstream and downstream of the site. In conclusion, the proposed project has been designed to ensure safe and efficient control of stormwater runoff in a manner that will not adversely impact the existing drainage patterns or adjacent properties. We anticipate that the subject project will not significantly impact the existing drainage infrastructure located within the existing development or the surrounding area. Orange Dev, LLC October 2022 DEC# 1021-99-025 4 Last Revised March 2023

APPENDIX

LOCATION MAP

Dynamic Engineering Consultants, PC 1904 Main Street Lake Como, NJ 07719 T. 732-974-0198 SITE Location Map www.dynamicec.com Lake Como, NJ • Chester, NJ • Toms River, NJ • Newark, NJ • Newtown, PA • Philadelphia, PA Bethlehem, PA • Allen, TX • Houston, TX • Austin, TX • Delray Beach, FL • Annapolis, MD

USGS MAP

Dynamic Engineering Consultants, PC 1904 Main Street Lake Como, NJ 07719 T. 732-974-0198 SITE USGS Map www.dynamicec.com Lake Como, NJ • Chester, NJ • Toms River, NJ • Newark, NJ • Newtown, PA • Philadelphia, PA Bethlehem, PA • Allen, TX • Houston, TX • Austin, TX • Delray Beach, FL • Annapolis, MD