T. Howard Duckett Reservoir

T. Howard Duckett Reservoir is an impoundment on the Patuxent River in Montgomery County, Maryland, created to supply drinking water and to provide flood control and recreational opportunities for the Washington metropolitan area. The reservoir, operated by the Washington Suburban Sanitary Commission (WSSC), lies near the border with Howard County, Maryland and serves suburbs such as Rockville, Maryland, Gaithersburg, Maryland, and Bethesda, Maryland. The site is situated within a landscape influenced by regional transportation corridors including Interstate 270 (Maryland), hydrological networks tied to the Chesapeake Bay, and land-use patterns shaped by Montgomery County Public Schools and local planning authorities.

Description and Location

The impoundment occupies a valley on the Patuxent River downstream of the confluence with several tributaries and is adjacent to communities like Clarksburg, Maryland and Poolesville, Maryland. The reservoir covers roughly 540 acres and is bounded by WSSC lands, county parks, and private parcels associated with developments in Germantown, Maryland. Topographically it sits within the Atlantic Coastal Plain transition to the Piedmont and is accessible from regional routes including Maryland Route 28 and Maryland Route 108. Nearby federal and state entities with jurisdictional interest include the Maryland Department of the Environment, National Park Service, and the Maryland Department of Natural Resources.

History and Construction

Planning for the reservoir began amid mid-20th-century water-resource development trends that included projects like the Conowingo Dam and the expansion of the Washington Suburban Sanitary Commission system. The project was authorized and constructed by WSSC during a period of suburban expansion in Montgomery County, Maryland influenced by post-war population growth and infrastructure programs associated with the Federal-Aid Highway Act of 1956. Engineering and construction firms contracted for design and earthworks had professional ties to the American Society of Civil Engineers standards of the era. The dam and impoundment were completed to provide a reliable potable supply for the growing Washington, D.C. metropolitan population and to augment storage capacity alongside facilities such as the Triadelphia Reservoir and Little Seneca Lake.

Hydrology and Water Supply

Hydrologically, the reservoir impounds flows of the Patuxent River within the Chesapeake Bay watershed and functions as a source for WSSC water production, treatment, and distribution to service areas in Prince George's County, Maryland and Montgomery County, Maryland. Its catchment receives surface runoff modulated by land uses in sub-watersheds draining through areas influenced by agriculture in Maryland, suburban impervious cover, and forested parcels on properties held by entities such as The Nature Conservancy and local land trusts. Water quality is monitored in the context of Clean Water Act obligations overseen by the Environmental Protection Agency regional office and the Maryland Department of the Environment, addressing nutrients, sediments, and emerging contaminants similar to monitoring at reservoirs like Loch Raven Reservoir and Gunpowder Falls State Park. Operational strategies include seasonal storage management, coordination with downstream flow requirements, and treatment at WSSC facilities comparable to practices at the Patuxent Water Filtration Plant.

Ecology and Recreation

Ecologically, the impounded area supports mixed riparian woodlands, wetland mosaics, and fish communities typical of mid-Atlantic reservoirs, including species with ranges overlapping those in Patuxent Research Refuge and Black Hill Regional Park. Avifauna observed in the vicinity include migratory bald eagles and waterfowl tied to the Atlantic Flyway, while aquatic assemblages mirror those documented in studies by the Maryland Department of Natural Resources. Recreational uses are regulated by WSSC and local authorities and include boating, angling, and limited shore access, with nearby trail networks connecting to county parks and regional greenways such as planning initiatives endorsed by Rails-to-Trails Conservancy and Montgomery Parks. Conservation efforts engage stakeholders including local land trusts in Maryland, community associations, and environmental NGOs to balance recreation with habitat protection.

Infrastructure and Management

The dam, spillway, access roads, and water-treatment interconnections are maintained by the Washington Suburban Sanitary Commission under regulatory oversight from the Maryland Department of the Environment and safety standards advocated by organizations like the Federal Emergency Management Agency for dam safety. Asset management integrates hydrologic modeling, routine inspections aligned with American Water Works Association guidelines, and emergency action planning coordinated with Montgomery County, Maryland emergency services and Howard County, Maryland counterparts. Long-term management priorities reflect regional planning documents such as the Montgomery County Master Plan and water supply studies that consider climate variability, population forecasts from the U.S. Census Bureau, and cross-jurisdictional collaboration with utilities serving the Washington metropolitan area.

Category:Reservoirs in Maryland Category:Montgomery County, Maryland