Carlsbad Municipal Water District (MWD) is a subsidiary district of the City of Carlsbad and delivers water and recycled water to its service area. Carlsbad MWD's extensive recycled water system distributes recycled water that provides over 20 percent of Carlsbad MWD’s total water needs. Carlsbad MWD owns the Carlsbad Water Recycling Facility (WRF), which treats secondary effluent from the Encina Water Pollution Control Facility. Carlsbad MWD also purchases recycled water from Vallecitos Water District. The Carlsbad WRF has a current capacity of 7 million gallons per day (MGD) with near-term expansion potential to 8 MGD.

The City of Escondido owns and operates the Hale Avenue Resource Recovery Facility (HARRF) that produces recycled water for local distribution. The City of Escondido produces and sells recycled water to its customers primarily for irrigation purposes, and also wholesales recycled water to Rincon del Diablo MWD. The HARRF currently produces up to 9 MGD of recycled water for use in the City of Escondido and Rincon del Diablo MWD's service areas. Through the short-term, a 9 MGD expansion of tertiary treatment system at the HARRF is anticipated.

The City of Oceanside owns and operates two wastewater treatment plants (WWTPs): La Salina WWTP and San Luis Rey Water Reclamation Facility (SLRWRF). Currently, recycled water from the SLRWRF serves the City’s Municipal Golf Course, Goat Hill Golf Course, SoCal soccer complex, Caltrans irrigation along Hwy 76 and I-5, and Whelan Lake, all within the City of Oceanside. The SLRWRF provides secondary treatment for most of the wastewater generated within the City of Oceanside's service area. The secondary treatment capacity of the existing SLRWRF is 13.5 MGD, while the tertiary capacity is 3.0 MGD, along with a 2.0MG reservoir for recycled water on-site storage. An Advanced Water Purification Facility (AWPF) is currently being constructed through the City’s Pure Water Oceanside program for Indirect Potable Reuse (IPR) via groundwater augmentation of the City’s Mission Basin. Water from the Tertiary facilities will be blended with up to 1.5MGD from the AWPF plant to provide high quality, low-TDS recycled water to the Morro Hills agricultural customers and others in the City’s planned Upper System.

Leucadia WWD wholesales recycled water to the City of Carlsbad for use on the south golf course at the Omni La Costa Resort and Spa. Leucadia WWD owns and operates the Gafner WRF, which has a 1 MGD capacity to treat water to tertiary levels. Secondary effluent is provided to the Gafner WRF from the Encina WPCF. Tertiary-treated recycled water from the Gafner WRF is supplied directly to the Omni La Costa Resort and Spa via a distribution system owned and maintained by Leucadia WWD.

Olivenhain MWD currently supplies recycled water to two separate portions of its service area. In the southeastern portion of the service area, wastewater is collected and treated to tertiary levels at the 4S Ranch WRF, which is a 2 MGD capacity water reclamation facility. The 4S Ranch WRF provides recycled water for non-potable irrigation. To meet recycled water demands in the southern portion of Olivenhain MWD's service area, Olivenhain MWD also purchases additional recycled water from the City of San Diego and the Rancho Santa Fe Community Services District (CSD). In the northwestern portion of its service area, Olivenhain MWD purchases recycled water from Vallecitos WD's Meadowlark WRF and San Elijo JPA's San Elijo WRF.

Rincon del Diablo MWD provides recycled water to its customers through a purchase agreement with the City of Escondido. Recycled water provided by the Rincon del Diablo MWD is produced at HARRF and used for landscape irrigation and industrial purposes. The Harmony Grove WRP is a 0.2 MGD tertiary plant providing wastewater and recycled water services for 750 new homes planned as part of the Harmony Grove Village development project within the Rincon del Diablo MWD service area. The WRP is owned and operated by Rincon del Diablo MWD to treat wastewater and produce recycled water for irrigation uses within the Harmony Grove Village development.

San Elijo JPA owns and operates the San Elijo WRF and approximately 19 miles of recycled water distribution pipelines and two covered reservoirs. San Elijo JPA is responsible for collecting, treating, and disposing of wastewater within its service area that includes the City of Solana Beach, portions of the City of Encinitas, portions of the community of Rancho Santa Fe, and the City of Del Mar. San Elijo WRF is a tertiary treatment facility that has a design capacity of 5.5 MGD through secondary treatment and a tertiary treatment capacity of 3 MGD. In 2013, San Elijo JPA added an AWT facility at San Elijo WRF that provides highly treated recycled water using microfiltration and reverse osmosis processes.

Santa Fe ID's service area covers portions of the City of Solana Beach and portions of the communities of Rancho Santa Fe and Fairbanks Ranch. Santa Fe ID serves water and recycled water to its customers. Wastewater services within Santa Fe ID's service area are provided by San Elijo JPA, and three separate Community Service Districts (Rancho Santa Fe CSD, Fairbanks Ranch CSD, and Whispering Palms CSD). Santa Fe ID purchases its recycled water supply from the San Elijo JPA.

Vallecitos WD provides water, wastewater, and reclamation services to San Marcos, the community of Lake San Marcos, parts of the cities of Carlsbad, Escondido and Vista, and other unincorporated areas in north San Diego County, but does not currently retail recycled water to any customers. Wastewater flows from the Vallecitos WD service area are treated at the Encina WPCF. Vallecitos WD owns and operates the 5 MGD Meadowlark WRF and wholesales recycled water to other agencies (Carlsbad MWD and Olivenhain MWD). Wastewater flows currently limit production of recycled water to just under 4 MGD on an average daily basis.