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Regular City Council Meeting Monday, April 14, 2008 Page 15 City Engineer Debra Bloom introduced Chuck Janski, P. E. Project Manager with Bonestroo who provided a presentation on 2007 Infiltration/Inflow Program within the City of Roseville. By way of background information for the public, Ms. Bloom noted that wastewa- ter collected in the Roseville sanitary sewer system flowed into main sewer lines owned and operated by the Metropolitan Council, who collected and treated wastewater from the seven county metropolitan area, with UI (inflow and infiltra- tion) consisting of clear water that made its way into the sanitary sewer system, mixing with wastewater already in the pipes, increasing the amount needing treatment. Mr. Janski reviewed various statistics of the system; lateral connections to MCES interceptor lines; monitoring by MCES of wastewater through eight flow meters; attempts to identify sources of inflow and infiltration with the intent to rehabilitate and reduce UI. Mr. Janski presented various "metersheds" or areas of study, their typical flow and data analysis; impact of significant rainfall events on the sanitary sewer system; and potential sources for stormwater. Mr. Janski advised that work completed to-date was the first step in the evaluation process to provide further guidance for subsequent investigation efforts; and out- lined proposed priorities or next steps, including temporary flow metering; cali- bration of lift stations 4, 5, 9, and 13 to supplement temporary metering data; ini- tiative private property source inspections (sump pumps and service line televis- ing; and public and private testing and flow rates (i.e., private sump tests; com- mercial roof drains); internal televising to document pipe conditions for future re- habilitation planning; all as indicated by available budget funds. Discussion among Councilmembers, Mr. Janski and Ms. Bloom included sources of inflow (i.e., manholes -City and MCES); smoke testing; 2008 workplan priori- ties recommended by staff, funded through the MCES surcharge reimbursement program; current work to determine sources (i.e., televising and flow metering; in- house manhole inspection program to determine any degradation and installation of seals); and clarification for the public on the City's $2.5 million annual cost to treat sanitary sewer inflow; cost to the City in exceeding allowable UI with an an- nual surcharge representing $82,538 to the City beginning in 2008 for such ex- cesses; and the need to solve that inflow of clear water represented by this five- year program. Councilmember Roe further clarified that the treatment is not a reimbursable cost; and that part of the problem was that MCES didn't have sufficient money to con- tinue treatment; without major expansion of their treatment facilities and addi- tional costs to taxpayers.