City of Oceanside IPR Project Presented at WRC March Meeting

Cari Dale, the City of Oceanside’s Water Utilities Director, came to the March meeting of the Water Reliability Coalition to give a presentation on her city’s Indirect Potable Reuse (IPR) project. 

Like all of San Diego County, the City of Oceanside imports the majority of its water. 

To help boost its local water supply, the City conducted two extensive studies on IPR. The first one, in February 2014, established the feasibility of IPR. The second, in December 2016, covered preliminary design, permitting and more. 

The City determined that the benefits of IPR include increased local water supplies, improved groundwater basin reliability, a decreased need to import water and improved groundwater quality. 

Here’s how IPR would work in Oceanside: 

Wastewater enters the San Luis Rey WRF for treatment. From there, it would pass through the Advanced Water Purification process and be deposited in injection wells (near-term) and spreading basins (long-term).  

The Advanced Water Purification process includes microfiltration, reverse osmosis and ultraviolet light and advanced oxidation. 

When the water is needed, it would be processed through the Mission Basin Groundwater Purification Facility to drinking water quality standards and distributed for use. 

The Mission Basin facility has a capacity of 6.4 million gallons per day. However, the basin levels have been decreasing and there is a need for groundwater recharge. 

The Mission Basin Aquifer was modeled to show the direction of water flow. Injection sites were chosen based on modeling, aquifer characteristics and location of existing wells. Injected water would stay underground for six months until extraction. 

Phase 1 of the project includes injection wells and is expected to be complete in 2022. Phase 2, which includes percolation ponds, is scheduled for 2028. 

To see Cari's presentation, click here.

The WRC thanks Cari Dale for a very informative and useful presentation! 

Jonathan Heller