Accomplishing Dual Objectives: Controlling CSO Discharges While Rebuilding Infrastructure.

Port Huron, Michigan began implementation of its CSO control program in 1997. As of 2012, the City had completed over 95% of the total program, with 32 of 33 projects completed or under construction, and with $171 million in expenditures. After considering both end of pipe controls and sewer separation, the City opted for separation. This decision was based on both the lower cost of the separation alternative and the additional benefits that would be realized in the replacement of severely deteriorated municipal infrastructure. This paper will evaluate the effectiveness of this approach to CSO control. The paper includes a discussion of the work included in the program, amount of infrastructure replacement accomplished, particular issues addressed in design to provide service to properties, implementation approaches to address private inflow sources, total costs and sources of funds, and cost savings versus an end of pipe approach. The analysis relies on original planning documents, updated planning and design documents, implementation cost data and finance data. The paper examines work included in the program, the overall impact on the condition of the City's infrastructure, and an assessment of the cost savings realized through the use of this dual purpose approach.