District backs out of California’s GRIP water-reuse project

One of the three main partners in a US$ 210 million indirect potable water-reuse scheme in California’s San Gabriel Valley has walked away from the project.

The board of the Upper San Gabriel Valley Municipal Water District (MWD) voted 4-0 on 1 March 2011 to remove itself from the Groundwater Reliability Improvement Program (GRIP) citing the lack of sound financing.

The GRIP project aimed to use membrane filtration to treat wastewater from the San Jose Creek Water Reclamation Plant operated by Sanitation Districts of Los Angeles County (SDLAC) to drinking-level standards, in a similar project to the Groundwater Replenishment facility in Orange County. The process would use micro/ultrafiltration, reverse osmosis, advanced oxidation, ultraviolet disinfection, decarbonation and lime addition.

The treated recycled water would then be conveyed via a pump station and conveyance pipeline to replenishment facilities constructed to enable recharging of water basins in the vicinity of the Santa Fe dam and recharge basins along the San Gabriel river.

MWD general manager Shane Chapman is quoted in the San Gabriel Valley Tribune as saying, “We are wary of jumping into a US$ 250 million project without sound financing in place.” Instead, Chapman and board members said they could find less expensive water sources, including increasing stormwater collection or improving conservation efforts.

The San Gabriel Valley Water Association (SGVWA), which represents water suppliers in the region, said that the amount of stormwater available for capture was often minimal and varied widely from year to year, and that it was impractical to assume conservation efforts would provide sufficient water.

The SGVWA board “feels strongly that a continued investment in a recycled-water recharge program is not only worthwhile but is critical to the (Central) Basin’s future water supply reliability,” board president Barbara Carrera wrote in a letter to the MWD board.

SGVA and SDLAC are reported to be continuing with the project, only at half the size. The original two-phase project would have provided a total of 46,000 AFY (56.7 million m³/year) of new water.