1600 MADISON ST 2016-01-01 MF Import

Section V. Runoff Control BMP's I:xistin� Conditions 1'he site is currently developed with single-iamily residences and a fire station. Drainage is contributory to the drainag� systems in Colby and Madison. The site area is approximately 1.29 acres. Developed Conditions The site will Ue developcd with a new fire station building, a truck display area and a parlcing lot. Drainage from the parking lot (Basin 2D) will be routed to two wet tanks, then an open storm water qualiry area and then to a detention vault located underground, and outletted to the e�cisting storm system in Colby Flowing south. Roof drainage (l3asin 1 D) will be outletted to the storm system in Colby flowing north and then east in Madison. 'I'he runoff outleuing to the north is less then the existing runoff and therefore detention is not required. Water QualitX The volume of the G month storm contributory to tlte water quality system is 2178 cubic feet (See Watenvorks output). 1'herefore 327 cf (15%) needs to be above ground. 'fhe water quality pond provides ll 12 cubic feet of storage. The pond is preceded by 3G" diameter pipe that provides the remainder of the water quality stcrage. The:e are 155 If of 3G", which provides 109G cubic feet of stonge.