CSO Diversion Chamber and Outfall Rehabilitation - Phase 1

Project Description: Pittsburgh Water is requesting Proposals for Design Services for the Combined Sewer Overflow (CSO) Diversion Chamber and Outfall Rehabilitation Project – Phase 1 which focuses on the rehabilitation of combined sewer outfalls. Existing combined sewer outfalls convey wastewater and stormwater flows to the nearest receiving water body during wet weather events in which the sewer capacity is exceeded. Recent inspections of Pittsburgh Water’s thirty-five (35) solely owned CSO Outfall structures have identified several locations exhibiting signs of deterioration and failure. Of these, nine (9) outfalls have been prioritized for detailed evaluation and design for rehabilitation measures with the goal of developing plans to address the identified deficiencies. Pittsburgh Water seeks to rehabilitate these outfalls to restore safe and effective discharge conditions, reduce erosion and sedimentation, and improve long-term performance of the collection system. In addition to physical rehabilitation, the project will evaluate the feasibility of separating portions of the existing combined sewer system. If technically and economically feasible, the goal would be to eliminate the combined sewer overflow and establish a dedicated storm only outfall to the receiving water body.