GELSENWASSER AG engages in the supply of water, electricity, and gas. It operates through the following segments: Water, Wastewater, Energy Networks, Energy Sales, and Investments and Others. The Water segment includes the production, sale, transport, and distribution of drinking water. The Wastewater segment is involved in activities of Chemiepark Bitterfeld-Wolfen GmbH. The Energy Networks segment consists of gas and electricity network operations. The Energy Sales segment purchases and trades natural gas, electricity, and heat to household customers, special contract customers, and resellers. The Investments and Others segment refers to holdings in municipal utilities. The company was founded on January 28, 1887 and is headquartered in Gelsenkirchen, Germany.