Los Angeles battles drought by releasing millions of shade balls into reservoir

Shade balls are four-inch diameter plastic spheres coated to block UV light. They are filled with water to weigh them down and are used to protect reservoirs from dust, rain, and birds, while also reducing algae growth. By blocking sunlight, they prevent harmful chemical reactions in the water. In Los Angeles, 96 million shade balls have been deployed, saving an estimated 300 million gallons of water from evaporating annually.

What is the diameter of the inner hollow of the shade balls?

• Four inches

• Eight inches

• Two inches

• Six inches

What is the primary function of the chemical coating on the shade balls?

• To increase their weight

• To make them waterproof

• To enhance their color

• To block ultraviolet light

How do the shade balls help in reducing algae growth?

• By absorbing nutrients

• By blocking sunlight

• By releasing chemicals

• By increasing water temperature

What harmful compound do the shade balls help prevent from forming in the water?

• Chlorine

• Sulfate

• Bromate

• Nitrate

Approximately how much water evaporation do the shade balls prevent annually in LA?

• 100 million gallons

• 200 million gallons

• 400 million gallons

• 300 million gallons