In 1977, the City created a new agency to manage its water supply and wastewater treatment and to regulate air quality, noise, and hazardous materials: the Department of Environmental Protection. DEP inherited the infrastructure, responsibilities, and documentation of many predecessor agencies dating back to the 1840s. That documentation comprises the bulk of the DEP archives and is still used in planning capital construction and rehabilitation projects, as well as watershed land management, facilities maintenance, and other operations.