OCEANSIDE — The City Council gave the green light to city Water Utilities staff to apply for a WaterSMART grant to fund 25 percent of a $62.9 million indirect potable water project on Dec. 21. The federal grant is specially for such projects, and can award $15.7 million to the city project design and build. Ratepayer revenues, and developer contributions will fund the rest of project costs.
Potable reuse water is highly treated, and can be used just like other potable water sources. The city currently purchases most potable water, and treats some local groundwater at the Mission Basin Groundwater Purification Facility.
The planned project will recharge the Mission Basin groundwater basin, with purified recycled water from the San Luis Rey Water Reclamation Facility through injection wells or spreading basins.
A highly scientific process will use microfiltration/ultrafiltration, reverse osmosis, free chlorination, oxidation process with ultraviolet irradiation/chlorina, and advanced oxidation with ultraviolet irradiation/chlorine disinfection.
Furthermore the process extracts only what it injects, with no impact on groundwater levels.
“The expansion will fund the replenishment of the aquifer at a rate of 3 million gallons/day,” Cari Dale, city water utilities director, said. “This is currently not existing.”
There is also capacity to increase the replenishment rate to 5 million gallon/day in the future.
The project build would include a new pump station, three new injection wells and four monitoring wells. The goal is for construction to be completed by 2022.
“It will provide increased reliability to our local water supplies,” Dale said.
The project timeline sets environmental compliances to be completed by September 2018. Construction follows with the design of pipeline and wells finished by March 2018, final design completed by September 2019, and a project contractor selected by March 2020.
Building is expected to take from April 2020 to September 2022. The city will be notified of grant results in June 2017. The hope is to receive funds, but regardless of the outcome the project will move forward. The city currently delivered 23,613 acre-feet of potable water. Of that amount 20,400 acre-feet is purchased water, and 3,213 acre-feet is treated groundwater.
By 2020 purchased potable water is expected to increase to 24,728 acre-feet, and potable groundwater to 3,300 acre-feet. Once the project build is completed in 2022, 3,300 acre-feet of potable reuse water will be added to the city water supply.