It is very dry in California. It does not rain for a long time. California tries to save water.
People make many black balls. The black balls save water. People move the balls into water. The balls stay on the surface of the water. The balls stop the sun. They also stop aquatic plants and birds.
One ball costs 36 cents. The balls work for 20 years. They save 1.1 million cubic meters of water every year.
Difficult words: surface (top), aquatic (water), cost (to have a price).
