12 2026 02 12 Crestmont CC Stormwater Management Report

Riprap Median Stone Diameter The median stone diameter, D50, in feet, shall be determined from the formula: 0 . 016 1 . 33 Where q = Q/Do D 50 = q For Horizontal Apron: T w D50 = 0.02 ft OR D50 = 0.3 inches Use Min. D50 = 3.0 inches Note: For discharge into Detention Basins, analyze the hydraulic characteristics of the basin for the design storm to determine the combination of conduit discharge and tailwater that results in the largest required D50 stone size. Riprap Lining Thickness The thickness of riprap lining shall meet at least one of the following criteria: 1. A thickness of at least three times the D50 size if a filter layer is not used. t= 0.8 inches 2. A thickness of at least two times the D50 size if a filter layer is used. t= 0.5 inches *Minimum required thickness is 6 inches. Use Min. t = 6.0 inches For tailwater elevation greater than or equal to the elevation of the center of the pipe La = 6 W= 6 For tailwater elevation less than the elevation of the center of the pipe La = 0 W= 0 Project: HW1-1 RIP RAP APRON DESIGN 300 Kimball

HW1-1 RIP RAP APRON DESIGN 300 Kimball Drive Parsippany, NJ WEST ORANGE NEW JERSEY P: 973.560.4900 F: 973.560.4901 Project No. Date: By: Ckd: Sheet. No. NJ Certificate of Authorization No: 24GA27996400 101049802 10/17/2025 TEG MJV 2 of 2