San Luis Obispo County officials are continuing to explore whether ocean desalination could help provide the region's future water supply. This comes as communities prepare for increased drought pressures and uncertainty over existing water sources.
Engineers presented an update on the county's Desalination Executable Solution and Logistics Plan, or DESAL Plan, during a recent Cambria Community Services District board meeting Thursday.
The county is currently in the planning phase of a multi-decade effort to evaluate whether a regional desalination project could help supplement existing water supplies. The process includes five phases extending through 2045. Officials are now in Phase 2A, which focuses on public outreach, evaluating alternatives, identifying environmental constraints and developing preliminary cost estimates.
Project engineer Anthony Cemo of Carollo Engineers said the study is not intended to identify a preferred project at this stage. Instead, engineers are comparing five potential alternatives located in the Cambria area, the Estero Marine Terminal area, Morro Bay, the South San Luis Obispo County wastewater treatment plant area and Nipomo.
Officials say the effort is being driven less by population growth and more by concerns about long-term water reliability.
“We wanted to explore another supply option, simply because this region has the benefit of having the ocean accessible and not a lot of regions do,” Cemo told board members. “So it's just prudent to investigate desal as well.”
Engineers said the projects would use reverse-osmosis technology to convert seawater into drinking water. They are also evaluating environmental impacts, permitting requirements and infrastructure needs.
One of the larger alternatives under consideration is located in the Morro Bay area. Engineers said that option could potentially take advantage of existing regional water infrastructure and serve multiple agencies.
Board members raised concerns about marine habitat impacts, the challenges of permitting coastal projects and the cost of transporting water to communities such as Cambria.
Preliminary planning-level estimates place the project’s capital costs between roughly $200 million and $600 million, depending on the size and location of a facility. County officials say no decisions have been made about whether to build a desalination project.
San Luis Obispo County is currently accepting public comment through an online survey as part of its community outreach process.
