An environmental scientist providing clean water to the city of Philadelphia explains how water is used to fight fires and to provide water for our homes, parks, and swimming pools. He shows us that river water provided by rain and runoff from farms is dirty and needs to be purified before human beings can use it. In a visit to the Fairmount Water Works he explains the mechanics of how water is brought to plants, purified and sent on to our homes and factories. The program closes with reasons for all of us to care for the health of our rivers.