L.A. has turned its water reservoir into a fun ball pit full of plastic balls.
On June 20, Los Angeles Mayor Eric Garcetti attended the release of the last batch of 4-inch black plastic balls, bringing their total to 96 million in the 175-acre reservoir. Located in Sylmar, its capacity reaches 3.3 billion gallons, enough to supply the city with drinking water for three weeks.
The function of the balls is to cover the water reservoir, limiting the amount of sunlight reaching the surface of the water. This keeps the water cooler and reduces evaporation from the reservoir, which also makes it less susceptible to algae, bacteria and chemical reactions that can produce harmful substances and contaminate the drinking water.
The balls cost 36 cents each, and the total comes to $34.5 million. Scientific research on the project has been conducted since 2008, with the result being 85% to 90% less water evaporation. This equals nearly 300 million gallons of water saved per year, which is enough for the needs of 8,100 L.A. residents.