 It promulgates and enforces the plumbing code for its jurisdiction as well as reviews and approves contract plans for extensions of water and sewer mains.The agency operates 3 reservoirs (plus shared access to a fourth reservoir), 2 drinking water filtration plants, and 6 wastewater treatment plants.It also collects wastewater which is treated at the Blue Plains Advanced Wastewater Treatment Plant (operated by DC Water) in Washington, D.C.