Manteca may spend $1.2 million to secure long-term savings to reduce future cost burdens for wastewater ratepayers.
Municipal staff is preparing a recommendation that the City Council trigger the alternate bid for the massive Woodward Avenue infrastructure project that would essentially bury much of the 2.5-mile long major sewer trunk line being installed even deeper to avoid the need for maintaining and powering three sewer lift stations in the future.
Such a move would allow the city to retrieve the $1.2 million upfront cost over 20 years and then avoid at least twice that amount in operating costs over the 50 years-plus minimum life expectancy of the sewer pipe.
The base bid called for the sewer line to gradually move closer to the surface until it was five feet below when it reached Main Street from the west along the Woodward Avenue corridor. By going with the alternative option that was bid out at the same time, the line would be deeper at Main Street - 15 feet to be exact. That would tie in with a line that was buried more than 10 years ago beneath the intersection to provide future sewer service to the Woodward Park neighborhoods. It means after the pipeline is completed, the sewer lift station on the northwest corner of Woodward Park would no longer be needed.
Public Works Director Mark Houghton noted the project - and bid - was purposely formulated so that when the project neared Airport Way there could be an assessment of how effective the contractor had been working in the varied soil along Woodward Avenue that runs the gamut from clay to sandy loam. The line already in place will still be used.
Clovis-based Floyd Johnston Construction - if the council concurs - would have $1.2 million added to the original contract of $9 million to pursue the deeper gravity flow. Houghton expects the investment to be recouped in reduced electricity and lift station-related costs over the next 20 years.
Funds for the work will be borrowed from growth fee accounts and repaid with interest from connection fees paid by future development along the 2.5-mile corridor that stretches from Main Street to McKinley Avenue. There are 1,500 building lots already approved along the corridor.
Houghton noted the overall project is designed to put storm drains a main sewer line, wider street, turn lanes, and landscaping in place all in one fell swoop to avoid going back repeatedly and making cuts into the asphalt.