12 2026 02 12 Crestmont CC Stormwater Management Report

EXECUTIVE SUMMARY The proposed stormwater management and conveyance systems for the proposed Crestmont Country Club & Eagle Rock Ave Improvements project have been designed in accordance with the New Jersey Department of Environmental Protection stormwater rules (NJAC 7:8), and the Township of West Orange stormwater regulations. The proposed development includes the construction of: • Installation of a new traffic signal at Eagle Rock Avenue & Oval Road intersection; • Widening along Eagle Rock Avenue to support the new lane geometry required at the new signal; • Re-alignment of the Crestmont egress driveway to connect into the new intersection; and, • Onsite improvements to both increase the number of parking spaces and re-design the parking around the new egress driveway. The proposed development disturbs more than one acre of land; therefore, this project is considered a “major development” from a stormwater management perspective, and the proposed design is required to address stormwater quantity, quality, and groundwater recharge requirements. The proposed stormwater management system consists of the following: • A subsurface conveyance system consisting of inlets, manholes, and pipes to convey stormwater runoff from the 25-year design storm event; • 2 small-scale bioretention basins; and, • 1 porous asphalt pavement system. By using the stormwater management measures identified above and reviewing the results of the detailed calculations provided in this report, the stormwater management design is in accordance with the Township of West Orange and NJDEP stormwater rules, regulations, and ordinance requirements in effect at the time of the preparation of this report. 1.0 INTRODUCTION This report addresses the engineering design of the stormwater conveyance and management system for proposed improvements within Eagle Rock Avenue and Crestmont Country Club in West Orange, New Jersey. The proposed stormwater management system is designed in accordance with: • New Jersey Department of Environmental Protection (NJDEP) stormwater rules (NJAC 7:8), last amended July 17, 2023; 1