Conowingo Dam

This article uses bare URLs, which are uninformative and vulnerable to link rot. Please consider converting them to full citations to ensure the article remains verifiable and maintains a consistent citation style. Several templates and tools are available to assist in formatting, such as reFill (documentation) and Citation bot (documentation). (August 2022) (Learn how and when to remove this message)

Conowingo Dam
Conowingo Dam, aerial view (1936)
Location of Conowingo Dam in Maryland
Official name	Conowingo Hydroelectric Station
Country	United States
Location	Cecil and Harford counties, Maryland
Coordinates	39°39′36″N 76°10′26″W / 39.66000°N 76.17389°W / 39.66000; -76.17389
Status	Operational
Construction began	1926 (completed in 1928)
Opening date	1928
Owner(s)	Susquehanna Electric Company
Dam and spillways
Type of dam	Gravity dam
Impounds	Susquehanna River
Height	94 ft (29 m)
Length	4,648 ft (1,417 m)
Reservoir
Creates	Conowingo Reservoir
Total capacity	310,000 acre⋅ft (0.38 km3)
Active capacity	71,000 acre⋅ft (0.088 km3)
Surface area	9,000 acres (3,600 ha)
Maximum length	14 mi (23 km)
Maximum water depth	105 ft (32 m)
Normal elevation	109.2 ft (33.3 m)
Power Station
Operator(s)	Constellation Energy
Commission date	1928
Type	Run-of-the-river
Turbines	7 x 36 MWe, 4 x 65 MWe
Installed capacity	548 MWe
Website Conowingo Hydroelectric Generating Station

The Conowingo Dam (also Conowingo Hydroelectric Plant, Conowingo Hydroelectric Station) is a large hydroelectric dam in the lower Susquehanna River near the town of Conowingo, Maryland. The medium-height, masonry gravity dam is one of the largest non-federal hydroelectric dams in the U.S., and the largest dam in the state of Maryland.

The dam sits about 9.9 miles (16 km) from the river mouth at the Chesapeake Bay, 5 miles (8 km) south of the Pennsylvania border and 45 miles (72 km) northeast of Baltimore, on the border between Cecil and Harford counties.

The dam supports a 9,000-acre reservoir, which today covers the original town of Conowingo. During dam construction, the town was moved to its present location about 1 mile (1.6 km) northeast of the dam's eastern end. The rising water also would have covered Conowingo Bridge, the original U.S. Route 1 crossing, so it was demolished in 1927. U.S. Route 1 now crosses over the top of the dam.

The Conowingo Reservoir, and the nearby Susquehanna State Park, provide many recreational opportunities.