Title 22 Filters 1, 5, and 10 Rehabilitation and Replacement Project

Request for Bids
West Basin Municipal Water District (West Basin) is accepting bids for the Title 22 Filters 1, 5, and 10 Rehabilitation and Replacement Project (CIP-10073). The solicitation phase will begin on April 13, 2026, and the bid opening is scheduled for May 7, 2026, pending any unforeseen delays. The Project is part of West Basin's current CIP program and has been approved by the Board of Directors to proceed with solicitation for bids.

West Basin Municipal Water District’s (West Basin) Edward C. Little Water Recycling Facility (ECLWRF) processes secondary effluent into four types of recycled water, including Title 22 recycled water. Title 22 water is disinfected tertiary recycled water used for irrigation and as source water for three (3) satellite treatment plants that serve refinery customers. At ECLWRF, Title 22 water is produced through clarification, filtration, and disinfection, then pumped from on‑site product water storage tanks into the recycled water distribution system through 48‑inch and 42‑inch pipelines. The distribution system is designed as a closed system with no intermediate storage outside of the treatment plants.

Currently, there are fourteen (14) monomedia gravity filters using anthracite coal, referred to as Title 22 Filters. The Title 22 Filters operate 24 hours per day, 7 days per week, providing tertiary-treated recycled water critical to West Basin's commercial and irrigation applications, satellite treatment plants, and refinery customers. The ECLWRF was originally placed into operation in the mid-1990s and has undergone significant additions and modifications since its inception, and these changes will likely continue. Filters 1 through 10, referred to as Train 1, were built during ECLWRF's initial construction phases, while Filters 11 through 14, referred to as Train 2, were added (converted) to Title 22 production after initially serving as a pretreatment process for other recycled water products (Barrier water/ Boiler Feed).

Several filters have required repairs over the years due to media loss into the underdrain, filtrate collection gullet, and backwash supply piping. Filters 8 and 9 were repaired in 2019, followed by Filter 2 in 2020 due to similar failures. Media loss affects water quality, facility operations, and production capacity. In 2025, Filters 3, 4, and 6 were repaired, along with structural repairs to the north wall of Filters 7 and 8. The scope of work for Filters 1, 5, and 10 includes, but is not limited to, the following:

• Removal of existing underdrain panels, laterals, and support channels, including hardware and gaskets for underdrain laterals.
• Removal of filter media in the basin, including in the floor, gullet, headers, backwash piping, and air headers.
• Installation of concrete end plugs to support underdrain laterals and gaskets.
• Installation of a gasket seal around the perimeter of the gullet.
• Installation of new underdrain laterals, including hardware and gaskets.
• Installation of new filter media, including backwash and skimming.
• Modify existing air metering tubes for flexible connection to each of the new underdrain laterals.
• Leveling of underdrain laterals along filter floor.
• Repair the concrete surface of the interior and exterior of the backwash troughs using cementitious mortar.