Item 2C: Ratification of MWMC Budget

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Metropolitan Wastewater Management Commission Capital Improvements Program 2. Secondary Clarifier Enhancements. This project includes design and construction of baffling, inlet energy dissipation, changing out of the flocculation well, construction of an outboard launder, and retrofitting of the suction header for the existing eight clarifiers. It also includes secondary gates. Enhancing the existing clarifiers will alleviate current operational problems and increase secondary treatment capacity for base and peak flows. Effluent quality and performance reliability will also be improved. 3. 9th and 10th Secondary Clarifiers. These two new secondary clarifiers (9th and 10th) will provide additional secondary treatment and peak flow management. The wet weather secondary capacity is proposed to increase from approximately 100 mgd to 160 mgd. In addition to these projects, the Clarifier Improvements Project includes related equipment replacement of clarifier rake arms, gates, and operating systems, and some major rehabilitation work on the clarifier floors and existing rake mechanisms. The project also includes construction ofthe contractor's courtyard, which will be used to support all projects at the plant, and the construction of a tie-in to the Tertiary Filters (a portion of a future project which will be more efficiently constructed with this project). Budget transfers needed to bundle these work items under one project package were discussed at the Commission's October 20,2005 meeting and approved by the Commission at their December 15; 2005 meeting. Construction is expected to begin in spring 2006 and be completed by spring 2008. Aeration Basin Phase 1 Improvements Design and Construction (formerly South Aeration Basin Improvements) FY 06-07 Capital Budget = $9,779,680 Expected Cash Flow: * FY 06-07 = $579,680 FY 07-08 = $6,200,000 FY 08-09 = $3,000,000 The MWMC NPDES wastewater discharge permit, issued by the DEQ in 2002, now places a limit on the allowable dry weather (May 1 st through October 31 st) discharge of ammonia. In order to meet this limit, the 2004 MWMC Facilities Plan identifies projects to increase the dry weather aeration basin treatment capacity to 65 mgd with respect to ammonia (i.e., with nitrification) and increase the sustained (i.e., on a weekly basis) wet weather treatment capacity to 130 mgd. The first phase of this project includes design and construction to add step feed processing, anoxic selectors, and fine bubble diffusers, and to remove hydraulic restrictions in a portion of both the south and north basins. It also includes primary effluent flow control gates for both north and south basins. Staff will be coordinating funding of system improvements that relate to equipment replacement. During alternative selection and predesign, West Yost Consultants and staff identified a modified Phase 1 project which was different from the Facilities Plan concept, but which had several advantages over the original concept. Instead of modifying four cells of the South Aeration Basin, the new concept entails modifying two cells in the North Aeration Basin and two cells in the South Aeration Basin. This concept allows for greater flexibility with respect to operations and also in timing future enhancements to the remaining basins. Design work is ongoing and expected to be Page 31 PROPOSED FY 06-07 BUDGET AND CIP