Title
Sanitary Sewer Infiltration and Inflow Program
Body
RECOMMENDED ACTION (Motion):
Staff is seeking Commission direction on proceeding with the I/I Program and which fee schedule to propose.
EXECUTIVE SUMMARY:
A Sanitary Sewer Infiltration and Inflow Program is proposed to reduce stormwater from entering the sanitary sewer system. The program requires revisions to City Code and the Sanitary Sewer Design Standards. The program would also create a policy on how to work with private property to reduce infiltration and inflow (I/I). The policy will require private properties to disconnect direct connections of stormwater pipes and repair or replace their sanitary sewer service laterals. Participation will be required either on their own or through a City cost sharing program.
BACKGROUND:
The City's 2014 Sanitary Sewer Master Plan (SSMP) recommended further investigative work to reduce sewer Infiltration and Inflow (I/I) in Oregon City. Over the course of four years, CCTV inspection, smoke testing, and additional flow monitoring were performed for continuation of the study work recommended in the SSMP. The investigations have identified areas of the sanitary sewer collection system that show leakage and excessive flow resulting from I/I. Reducing I/I provides benefits to the public by resolving capacity issues for treatment at the Tri-City Wastewater Treatment Plant.
The City is currently under contract with Murraysmith, Inc. for services related to the City's I/I reduction program. Murraysmith has provided engineering assistance for further interpretation of testing results, assistance with planning further pipe condition assessment efforts, and development of short, medium, and long-term correction capital improvement project programs. Tasks also include developing policy and construction standards for rehabilitation or replacement of private laterals and disconnection of inflow sources such as gutter downspouts and foundation drains.
The I/I policy requir...
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