Los Angeles has been blackballed.
The city has completed a program of covering open-air reservoirs with floating "shade balls" to protect water quality.
City officials this week dumped the last 20,000 of 96 million black balls into the Los Angeles Reservoir in Sylmar, 40 kilometres northwest of downtown.
The 10-centimetre-diameter plastic balls block sunlight from penetrating the 175-acre surface of the reservoir.
That prevents chemical reactions that can cause algae blooms and other problems, allowing the Department of Water and Power to meet U.S. Environmental Protection Agency water-quality requirements.
They have the added perk of aiding with the ravages of the drought, and are expected to keep about 1 billion litres annually from evaporating.
"In the midst of California's historic drought, it takes bold ingenuity to maximize my goals for water conservation," Mayor Eric Garcetti said in a statement, noting that the effort is "emblematic of the kind of the creative thinking we need to meet those challenges."
The 36-cent balls also will help prevent evaporation of 1 billion litres of water annually from the 12.5-billion-litre reservoir, the DWP said.
The city began using shade balls in 2008, and they now also cover the Upper Stone, Elysian and Ivanhoe reservoirs.
LA just completed a project at the LA Reservoir to save 300 million gallons of water by deploying shade balls on its surface, saving our city over $250 million dollars while keeping our water clean & safe.
Posted by Mayor Eric Garcetti on Monday, August 10, 2015
