2026 02 12 Crestmont CC and Eagle Rock Ave Stormwater Management Report

Based on "Standards for Soil Erosion and Sediment Control in New Jersey," dated 2014 TABLE 12-1 ALLOWABLE VELOCITIES FOR VARIOUS SOILS SOIL TEXTURE ALLOWABLE VELOCITY (ft./sec.) 1. Sand 1.8 2. Sandy Loam 2.5 3. Silt loam (also high lime clay), loam 3.0 4. Sandy clay loam 3.5 5. Clay loam 4.0 6. Clay, fine gravel, gradded loam to gravel 5.0 7. Cobbles 5.5 8. Shale (non-weathered) 6.0 Soil type where outfall is located = 2 (Note: Select number designating soil texture above) allowable velocity = 2.5 ft/sec v (velocity) = 1.68 ft/sec Rip Rap Apron required? 0 (1 = yes, 0 = no) Given: Do (max inside height) = 1.25 feet Wo (max inside width) = 1.25 feet Q (discharge) = 2.04 cfs (25 year storm) *q (unit discharge, = Q/Wo) = 1.7 cfs / foot ** Tw (tail water) = 1.8 feet * for the conduit design storm or the 25 year storm, whichever is greater ** for areas where Tw cannot be computed, use Tw = 0.2 Do. For discharge into detention basins, Tw shall equal the 2 year storm elevation in the basin. Riprap Apron Dimensions I. The length of the apron, L (in feet), shall be determined from the formula: q La = (1.8 1/ 2 ) + 7Do Tw < ½ Do La = 0 feet Do q La = 3 1 Tw > ½ Do La = 5 feet Do2 II. Where there is no well-defined channel immediately downstream of the apron, the width, W, of the

½ Do La = 5 feet Do2 II. Where there is no well-defined channel immediately downstream of the apron, the width, W, of the outlet end of the apron shall be as follows: For tailwater elevation greater than or equal to the elevation of the center of the pipe, W = 3Wo + 0.4 La W= 6 feet For tailwater elevation less than the elevation of the center of the pipe, W = 3W o + L a W= 0 feet Where La is the length of the apron determined from the formula and Wo is the culvert width. Project: FES1-2 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 1 of 2