Clearwater Program & Developers Flow Credit Bank

Washington Suburban Sanitary Commission (WSSC) entered into a Consent Decree in 2005, which mandated sewer system enhancements to eliminate Sanitary Sewer Overflows (SSO’s) and free up capacity in hydraulically challenged basins. As the sewer rehabilitation work continues, WSSC is now addressing the introduction of Inflow/Infiltration (I/I) from private property sources through the WSSC Clearwater Program. WSSC has modified their procedures to allow developers to complete sewer rehabilitation in lieu of capacity enhancement projects and is building a Flow Credit Bank process to allow future development to move forward in sewer basins that have hydraulic capacity constraints by using available credits. WSSC is also conducting a Clearwater Pilot Program intended to identify and quantify sources of I/I from private property as well as reductions through private side rehabilitation work. The work presented in this paper will describe each of the facets related to the WSSC Clearwater Program.