Report 4 13 2026

​ENSURPLAN, INC.​ ​ ww.Ensurplan.​​net​ w ​ ivil Engineers & Land Surveyors C Ph: (732) 469-0400​ ​Certificate of Authorization 24GA27997700​ ​STORMWATER DRAINAGE REPORT​ ​04/13/26​ ​Minor Subdivision 15 Ridgeway Ave West Orange, NJ​ ​Design Discussion​ ​(continued)​ ​ he below grade infiltration basin has been sized as required to restrict the volumes of the​ T ​design storms and provide the necessary reductions in rate. It is also required that the designed​ ​pond volume can drain within 72 hours via infiltration.​ ​The maximum storage for the projected 100 year storm is 3,667 cf.​ ​Time to empty: (3,667 cf max / (125.5’ x 12.75’) sf flat bottom) x 12”/ft / 0.5”/hr = 55 hrs​ ​The maximum volume within the pond 4,026 cf.​ ​Time to empty: (4,026 cf max / (125.5’ x 12.75’) sf flat bottom) x 12”/ft / 0.5”/hr = 60 hrs​ ​ he infiltration rate utilized in the design analysis is 0.5”/hour which is half of the infiltration rate​ T ​measured of 1.00”/hr at the soil log situated within the infiltration bed.​ ​7​ ​Mailing Address: Post Office Box 4304, Warren, NJ 07059​