Manufacturing of water pumps, vacuum pumps, valves, environmental protection equipment, dredging machinery, low-voltage complete equipment, marine equipment, marine auxiliary machinery, electric motors, reducers and accessories, and rollers; design, manufacturing, and installation of mobile pump stations, floating pump stations, prefabricated pump stations, cable-stayed pump stations, and gate pumps; installation of mechanical and electrical equipment; design and construction of wastewater treatment plants; construction of water diversion projects; construction of river, lake, and seawater treatment; production and sales of hydraulic metal structure products; sales of municipal engineering vehicles and water engineering vehicles; export business of self-produced products and technologies, and import business of required machinery, spare parts, raw materials, and technologies, except for goods and technologies restricted or prohibited by the state.