Green lawns, old appliances and leaky pipes all consume significant amounts of California’s water, and researchers have calculated in a new study that the state could reduce water use by more than 30% in cities and suburbs by investing in measures to use water more efficiently.

The study by the Pacific Institute, a water think tank in Oakland, also found big untapped potential for urban areas to reduce strains on overused rivers and aquifers by investing in local projects to recycle more wastewater and capture more stormwater.