Through flushing toilets and running faucets, the city of Modesto produces millions of gallons of wastewater a day, just a stone’s throw from some of the driest agricultural areas in the state.
In a few years, that wastewater — treated and disinfected — could flow to farms in the Del Puerto Water District, in what would be the largest urban-to-agriculture water recycling project in the state.
Even during the drought, around 240,000 Modesto residents produce a steady stream of water — in the form of sewage.
“Water is water,” says Will Wong, engineering division manager for the city of Modesto. “As long as it’s wet, it’s water and it’s valuable.”
The city’s wastewater treatment plant is undergoing a $150 million upgrade to meet new water quality requirements. Currently, most of its wastewater is discharged into the San Joaquin River, and to protect the river, the city is being required to meet higher, “tertiary,” standards.
In what’s called the North Valley Regional Recycled Water Program, the Del Puerto Water District would construct a six-mile, $100 million pipeline to carry the wastewater from the city to the Delta Mendota Canal. From there, it would go to the district’s farms.
The water would be expensive for farmers, four to five times normal prices, but Hansen says that’s the cost of reliability. Growers like Jim Jasper are more than willing to pay.
“When something like this comes up, you don’t have to think about it twice,” says Jasper, who owns Stewart & Jasper Orchards.
Other agricultural areas are taking notice, as they face their own drought shortfalls.
“There’s absolutely more potential for recycled water use in California,” says Heather Cooley of the Pacific Institute, a non-profit water think tank in Oakland. According to her analysis, California could be using two to three times more recycled water for many purposes, including urban landscape and golf course irrigation.
“You need to understand where that water would have gone,” Cooley says. “Is it providing important environmental flows? Is it providing water to a downstream community such that if you’re recycling it, there’s no longer water for that community?”
Two agricultural water districts are protesting the North Valley Regional Recycled Water Program, saying it could harm the area.
Westlands Water District, the largest irrigation district in the country, is challenging the project for its possible effects on the San Joaquin River.
The river is used so heavily by the region that it runs completely dry in some years. As a result, minimal standards have been put in place to ensure enough water is flowing to protect water quality and the endangered salmon that use the river. When those standards aren’t met, water pumping to local irrigation districts must be slowed down.
Wastewater from Modesto and Turlock makes up only a tiny fraction of the overall flow of the San Joaquin River, but Westlands would rather see it go into the river, instead of being recycled, to help meet water quality standards.
Officials with the Turlock Irrigation District say they’d rather see the wastewater used to replenish local groundwater, and to combat overpumping in the area. The City of Turlock relies on groundwater for its water supply, and after it’s treated, it’s discharged into the San Joaquin River.