Seattle Public Utilities and King County join efforts in reducing sewer overflow

Seattle Public Utilities (SPU) and King County currently manage more than 125 combined sewer overflow facilities.  Since SPU’s combined sewers are connected to King County’s large-capacity conveyance facilities, the existing and proposed CSO controls considered by either agency can have impacts reaching into both systems. 

In an effort to coordinate CSO reduction activities, SPU has recently initiated a joint project with King County to develop a system-wide MIKE URBAN model of the King County trunk network which serves as the backbone of the City of Seattle system. The objective is a better understanding of both agencies’ system operations aimed at CSO reduction as mandated by their state and federal regulators. The integrated model will facilitate a shared understanding and technical analysis of the system, an integrated evaluation of the impacts of proposed projects, and a determination of the benefits and return on investment for both agencies.