Mayor Eric Garcetti released the final 20,000 balls onto the surface of the Los Angeles Reservoir earlier this week as part of a $34.5m project to protect the city’s water.

The Los Angeles Department of Water and Power (LADWP) used 96 million ‘shade balls’ – small, black, floating plastic balls – to prevent 85-90% of surface water evaporation.

The shade balls also help protect the water quality by preventing contamination from sunlight-triggered chemical reactions and wind-blown sand and dust.

The infrastructure investment is thought to represent $250m in savings for the city, preventing the loss of more than 300 million gallons of water each year.

Historic drought

Mayor Garcetti said: “In the midst of California’s historic drought, it takes bold ingenuity to maximize my goals for water conservation. This effort by LADWP is emblematic of the kind of creative thinking we need to meet those challenges.”

California’s historic drought has led to mandatory water restrictions in the state, with Governor Jerry Brown ordering businesses and residents to cut water use by 25% in April. Agriculture is responsible for around 80% of the state’s water use, but farmers have been spared so far from mandatory water reduction.

Garcetti said: “We’ve led the charge to cut our city’s water usage by 13%, and today we complete an infrastructure investment that saves our ratepayers millions and protects a vital source of drinking water for years to come.”

The shade balls on the 3.3bn gallon reservoir help the state meet federal water quality requirements, with a further $100m ultraviolet water treatment facility under construction to help prevent further water contamination.

LADWP general manager Marice Edwards said the shade balls project showed how “engineering meets common sense.”

Edwards said: “Shade balls are an affordable and effective way to comply with regulations and helps us continue to deliver the best drinking water to our customers.”

City councilmember Mitchell Englander said: “As the drought continues, it has never been more important to focus on innovative ways to maintain the highest quality drinking water for our 4 million residents.”


The state of California has imposed fines for residents wasting water as part of a major campaign to cut water use. Water-wasters can expect fines of up to $500 a day.

Major Silicon Valley firms have been forced to look into new water saving measures due to the colossal water-use of data centres.

In recent months local residents across the state have taken up a vigilante campaign to ‘drought-shame’ water wasting celebrities in wealthy areas such as Beverly Hills, where homes can be seen with immaculate lawns and private golf courses.

Overall the State Water Resources Control Board reported in June water consumption had fallen 27%, meeting the Governor’s conservation targets.

Matt Field

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