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03/27/2007 capacity. The estimated Moderate Intensity alternative-related ADDWF increment of 367,334 gpd (0.367 mgd) is less than the City's purchase option of 1.915 mgd. In recent years, wastewater flow to the SBSA collection system from Redwood City has occasionally exceeded the current peak wet weather flow capacity right (exclusive of Redwood Shores) of 25.9 mgd. Since 1994-95, the City has exceeded its allocated capacity nine times during the winter. Since the SBSA treatment capacity allocation to Redwood City is already being exceeded during wet weather, the current allocation from the SBSA is inadequate to serve the project's projected Moderate Intensity alternative ADDWF increment in addition to existing SBSA commitments. Because the SBSA wet weather treatment capacity allocation to Redwood City is already being exceeded, the Precise Plan Moderate Intensity alternative-related and cumulative impacts on wet weather flow treatment capacity are considered to represent a potentially significant project and cumulative impact. Mitigation 10-2. If the Precise Plan Moderate Intensity alternative is adopted, prior to City approval of any future individual development proposal in the Precise Plan area, if determined necessary by the City Engineer, the City shall purchase from the added SBSA the treatment capacity necessary to accommodate the projected net increase in wastewater generated by the proposed development. Each future individual development's ultimate treatment capacity requirement shall be calculated in the final permitting stage. The project applicant shall reimburse the City for the costs associated with the individual development's fair share of the purchase of this treatment capacity (e.g., the capacity option itself, and associated administrative costs) and implementation of one of the transmission capacity improvement options listed below, the procedural details of which shall be included in a development agreement for the project. In order to mitigate the limited transmission capacity during wet weather from the Precise Plan area to the SBSA treatment plant, implementation of one of the following options would be necessary: (1) Upgrade the influent lifting station at the treatment plant, upgrade the treatment plant itself as necessary, install a new gravity sewer line from the SBSA pump station at Maple Street, and upgrade the pump station at Maple Street; or (2) Replace 21,000 feet of 6-inch, 3,600 feet of 8-inch, and 2,000 feet of 10-inch pipes within the Precise Plan area, and 6,200 feet of 6-inch pipes outside the Plan area, to reduce the wet weather flows. By replacing existing wastewater collection pipes, and thus reducing infiltration and inflow, the increase in ADDWF from Precise Plan-related growth would be mitigated, and the wet weather flow would not increase from Plan-facilitated development. An additional benefit would be the replacement of all substandard 6-inch pipes with City standard 8-inch pipes. Atty/Reso/Reso.1683 22 14769 030707 Muff #613