Blue Plains Wastewater Treatment Plant, District of Columbia

The Blue Plains Wastewater Treatment Plant is the main sewage treatment plant for Washington DC. It is operated by DC Water, which claims that is the largest advanced wastewater treatment plant in the world. This may be because it has secondary treatment system that substantially reduces its nitrogen output, in order to help preserve the water quality of Chesapeake Bay, located downstream. The plant also uses thermal hydrolysis to treat its sewage sludge, at a scale beyond other plants, and uses some of this dried sludge to generate electricity for the plant. It is located at DC’s southernmost point on the Potomac. It opened on 1937, and now handles up to 300 million gallons of waste per day, serving more than 1.6 million customers in DC and its suburbs.