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ARDEN HILLS CITY COUNCIL - JULY 10, 2006 3 . at that time. He noted if they waited another year, the property value would probably go up agam. Councilmember Holden stated she was not ever sure what was included in the appraisal last year. She stated she disagreed with Councilmember Larson and did not believe last year's appraisal was equal to this appraisal. 6. PUBLIC HEARINGS None. 7. NEW BUSINESS A. Inflow/Infiltration Update Ms. Giga stated the City of Arden Hills was notified by the Metropolitan Council that there is a significant inflow and infiltration (1&1) problem in the City. 1&1 is clear water that makes its way into the sanitary sewer system. Arden Hills' sanitary sewer system flows into a system owned and operated by the Met Council, which ultimately reaches a wastewater treatment plant. She further defined 1&1 by stating infiltration is a result of groundwater entering the sanitary sewer system via cracks in the sewer pipes, leaky joints, or deteriorated manholes. The main source of inflow is stormwater that enters the sanitary system from rain leaders, sump pump discharges or . foundation drains, none of which are supposed to be connected to sanitary sewer lines. Based on current data, the City could face a $500,500 surcharge with Met Council if 1&1 is not reduced. This charge would be paid over five years, starting in 2007. The surcharge would be retrievable if the City spends any money to reduce 1&1. The City could receive a surcharge adjustment by submitting an application for credit for work to be done in 2007. She indicated staff has begun some background work to determine necessary improvements. O&M feels that leaking manholes are a major source ofI&1. Crews have spent time this spring inspecting manholes, filling out manhole reports on the existing conditions and noting needed improvements. City staff has discussed repair methods, and it is anticipated that manhole repairs will begin shortly. Repair work will include placing new seals on the manholes and raising the elevation as needed to prevent water from getting in. She stated staff is also gathering information from past O&M procedures and projects that could be used as to assist in 1&1 reduction as well. Sump pumps have been a common source ofI&I in other cities. When Arden Hills replaced the residential water meters in 1999-2000, sump pumps were also inspected. However, staff is not confident that these inspections were successful in disconnecting all of the sump pumps from the sanitary sewer system. . She stated staff will focus first on repairing/sealing manholes to determine if this is, in fact, the main source of 1&1. If this does not show a reduction in 1&1, staff will continue to evaluate other