The Beth Israel Deaconess Cancer Center and Surgical Pavilion project includes an addition to the existing Beth Israel Deaconess Hospital and a new two-level parking garage. The project has been designed to treat storm water runoff from the garage and building roofs, as well as pavement areas adjacent to the new construction.
The project increased the impervious area at the site by approximately 9,500 square feet.Increasing the impervious area on a site increases the rate and volume of storm water leaving the site if left untreated. The storm water management system for the site includes best management practices that mitigate potential increases in storm water runoff, promotes infiltration of storm water to groundwater, and provides water quality treatment. Water quality treatment was achieved by maximizing infiltration of runoff from newly proposed impervious areas and installing proprietary water quality structures prior to discharge.These best management practices were selected because they efficiently remove storm water pollutants including total suspended solids in sites where space is limited.
In total, there are three storm water management areas (SWMA) that facilitate and promote infiltration. SWMA #1 consists of 30-inch perforated plastic pipes surrounded by crushed stone. SWMA #2 is an above ground infiltration basin, with additional crushed stone below the surface to provide enough volume to hold the stormwater from the garage roof. SWMA #3 consists of 24-inch perforated plastic pipe surrounded by crushed stone.