Los Angeles County officials have been dumping hollow black polyethylene balls — aka “shade balls” — into city reservoirs to prevent the water from evaporating.
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Los Angeles mayor Eric Garcetti has said that these balls will protect water quality by "preventing sunlight-triggered chemical reactions, deterring birds and other wildlife, and protecting water from rain and wind-blown dust."
The balls cost $0.36 a pop* and are designed to cover a large percentage of the water's surface, acting as a nice shade to help with evaporation and prevent algae formation.
Plus, it's really fun to watch them roll down that ramp and into the water.
