Watering the lawn less, taking shorter showers, and switching to a low-flow toilet all conserve water. And they also reduce carbon pollution.

“About 20% of the state of California’s energy use is associated with the water system,” says Frank Loge of the University of California, Davis.

He explains that every step of a water system uses energy: pumping water from lakes and reservoirs, treating it to make it safe to drink, and pumping it into homes and businesses.

Then, if it’s sent down a sink or toilet, it’s usually processed at a wastewater treatment plant, which Loge says takes a tremendous amount of energy.

In Los Angeles, the water department offers rebates on high-efficiency toilets, low-flow sprinkler nozzles, and other water-saving devices.

Loge and his team compared the energy saved from these programs to the results of programs geared specifically towards energy efficiency, such as rebates for efficient appliances.

“Water conservation was highly effective at saving energy,” he says. “It was cost-effective compared to other energy programs.”

And using less energy means emitting less carbon pollution. So investing in water conservation can also help protect the climate.

Reporting credit: Sarah Kennedy/ChavoBart Digital Media