Reports of mysterious "shade balls" in Los Angeles reservoirs have been bobbing to the surface.
But they're there for a reason. The black, plastic spheres, partially filled with water, that are now in a Los Angeles reservoir by the millions are part of a $34 million project to protect the region's water supply from contaminants and evaporation.
The plan is expected to save the city $250 million, compared with other available plans, according to a press release.
The idea was developed by a former biologist with the Los Angeles Department of Water and Power, who was inspired by the use of similar balls to keep birds from landing in ponds along airplane runways. They cost 36 cents each to make, and they line the surface of three other reservoirs in the Los Angeles area. Ninety-six million of the spheres are floating in the Los Angeles Reservoir alone, according to the release.