J_2024 05 09_West Orange Stormwater Management Plan

Stormwater Management Plan Revision 0 Hydrology and Hydraulics Each bioretention basin will have its own outlet control structure (Refer to Table 2.6) that discharge into a subsurface pipe network that will ultimately drain to Outfall O-1B, located in Mount Pleasant Avenue. Table 2.5: Bioretention Basin Control Devices Outlet Control Structure Name CS-01 CS-02 CS-03 CS-04 CS-05 2.4 Control Device Outlets (1) – 2.5” circular orifice @ 596.00’ (1) – 12.0”W x 2.5”H rectangular orifice @ 600.50’ (1) – 48.0”W x 48.0”L overflow orifice @ 602.40’ (1) – 12” diameter RCP (SD-21) @ 591.57’ (1) – 2.5” circular orifice @ 598.00’ (1) – 36.0”W x 2.5”H rectangular orifice @ 601.10’ (1) – 48.0”W x 48.0”L overflow orifice @ 601.40 (1) – 12” diameter RCP (SD-22) @ 590.35’ (1) – 2.5” circular orifice @ 594.00’ (1) – 2.5”W x 2.5”H rectangular orifice @ 598.50’ (1) – 48.0”W x 48.0”L overflow orifice @ 601.15‘ (1) – 15” diameter RCP (SD-23) @ 588.19’ (1) – 2.5” circular orifice @ 594.70’ (1) – 2.5”W x 2.5”H rectangular orifice @ 598.30’ (1) – 48.0”W x 48.0”L overflow orifice @ 599.65‘ (1) – 15” diameter RCP (SD-24) @ 586.53’ (1) – 2.5” circular orifice @ 593.80’ (1) – 12.0”W x 2.5”H rectangular orifice @ 598.20’ (1) – 48.0”W x 48.0”L overflow orifice @ 599.65‘ (1) – 18” diameter RCP (SD-25) @ 584.63’ Results The post-developed watersheds PO-DA A and PO-DA M, which discharge into the existing onsite stormwater pipe network that drains to the AquaShield, will be a reduction in size from the pre-developed watersheds PO-DA 6 and PO-DA 8, thus providing no adverse impact to the original AquaShield design or outfall. As summarized in Section 2.3, a series of bioretention basins with underdrains will be constructed to address the water quantity for the peak discharge for the newly developed areas associated with the substation expansion, specifically post-developed watersheds PO-DA C, PO-DA E, PO-DA G, PO-DA I, and PO-DA J. Flow rate calculations were completed using HydroCAD software. Refer to Appendix B for the calculations. Public Service Electric & Gas Company 2-6 Burns & McDonnell