Water recycling projects in California are nothing new, but continued improvements and investments will be an important feature of water conservation moving forward. Multiple research projects are looking at various aspects of increasing the use of recycled water in agricultural production. As technology continues to advance and water regulation continues to increase, the overall value of recycled water will be further enhanced.
In roughly one year, the North Valley Regional Recycled Water Project went from the construction phase to delivering recycled urban wastewater to farmers in the San Joaquin Valley. The project is a collaborative effort between the Del Puerto Water District, the cities of Modesto and Turlock and other partners. It allows for treated municipal wastewater from Modesto and Turlock to be used for local agricultural irrigation. Recycled water deliveries began in December 2017 and the Del Puerto Water District is expecting to receive 16,500 acre-feet of water this year.
Another recycled water project in Paso Robles is getting closer to completion. According to a California Environmental Quality Act study checklist, once the plant is running at full capacity it will be able to process nearly 1.6 billion gallons a year. The $14.4 million dollar plant will provide treated water to help supplement the agricultural industry’s reliance on groundwater pumping. Construction just passed the halfway point with an expected completion date in January 2019. Recycled water projects like these can create a continuous source of water for farmers, providing a level of stability from year to year.
In looking to other sources of recycled water aside from municipal wastewater, researchers are evaluating the use of oilfield-produced water (OPW) in crop irrigation. A 2015 study from the Pacific Institute illustrated California’s seven major oil-producing counties have the potential to provide a combined 359 million gallons of OPW every day. There is already a substantial number of growers using recycled water, which multiple studies have suggested can result in significant increases to crop yield.
A statewide survey conducted in 2015 found that 30 percent of all recycled water, totaling 216,589 acre-feet, was being used in agricultural irrigation. Estimates also showed that the state could potentially recycle another 1.5 million acre-feet of water annually by 2030. Future demand estimates also illustrate that agricultural reuse could increase more than three times current levels by 2030, furthering the need for continued investment in water recycling projects.