Pure Water Soquel Project to Focus on Obtaining Treated Water for Proposed Advanced Water Purification Facility
At its March 7th meeting the Soquel Creek Water District Board of Directors voted to remove the option of using untreated wastewater as a source for its Pure Water Soquel project, and also identified additional possible sites for locating the proposed advanced water purification facility to be considered.
This means the alternative to use raw wastewater will no longer be considered as part of the project definition currently being analyzed in the upcoming environmental impact report (EIR). Instead, the project will focus on obtaining secondary or tertiary treated water from the City of Santa Cruz which will then undergo additional purification at the proposed facility. A draft memorandum of understanding with the City of Santa Cruz for secondary treated water is anticipated to be brought to the District Board for consideration in early April.
Pure Water Soquel is a groundwater replenishment project that could add purified water to the local underground water basin - the area's sole source of water, which is suffering from severe overdrafting. Adding water via recharge wells will replenish the basin, restore protective groundwater levels, and prevent seawater intrusion/contamination from moving farther inland. Use of the already-cleaned recycled water from the Santa Cruz Wastewater Treatment Facility (SC WWTF) is an example of the beneficial reuse of treated secondary disinfected effluent that is otherwise discharged out to the Pacific Ocean. It's estimated that up to 25% of the treated wastewater that is being put into the ocean can be captured and beneficially reused for groundwater replenishment.
"We're pleased to be able to move forward with taking the use of untreated wastewater off the table, allowing us to carefully consider a smaller facility that will be able to purify water to high-quality water standards - while also evaluating additional options for where this smaller facility could be sited," said Board President Tom LaHue.
In addition to exploring an advanced purification facility site next to its headquarters office and the PG&E substation in Soquel, the District Board approved at its Tuesday night meeting to include the Santa Cruz Wastewater Treatment Facility as a possible water purification site in its environmental review and directed staff to further explore the merits of a few other sites that the District recently re-evaluated.
There are a number of advantages to utilizing secondary/tertiary-treated water, instead of raw wastewater. Purifying secondary effluent requires a smaller footprint, uses significantly less energy, and costs less than a facility that would treat raw wastewater. All of these advantages support the Board's decision to move toward an advanced water purification facility that utilizes treated/recycled water instead of untreated wastewater.