Domestic wastewater includes black water, or wastewater from toilets, and gray water, which is wastewater from all sources except toilets. Black water and gray water have different characteristics, but both contain pollutants and disease-causing agents that require monitoring. Nondomestic wastewater is generated by offices, businesses, department stores, restaurants, schools, hospitals, farms, manufacturers, and other commercial, industrial, and institutional entities. Storm water is a nonresidential source and carries trash and other pollutants from streets, as well as pesticides and fertilizers from yards and fields.