Located on the east shore of the lower Susquehanna River in Dunmore Township, the site derives its name from the original Muddy Run, a small tributary of the Susquehanna River that ran through the valley. In 1967 it was flooded to create a 985-acre-storage reservoir, owned and operated by the Philadelphia Electric Company (PECO). The IBA also includes a 100-acre recreational lake, 500-acre park, and an additional 1,900 acres of old fields, woodlands, cultivated fields and plantings by the Pennsylvania Game Commission and Natural Resources Conservation Services - all created as mitigation for the hydroelectric project. A one-mile stretch of continuous woodlands borders the river adjacenet to the site.

Directions: From Lancaster, south on Rt. 222 to Rt 272, to right on Rt. 372, to park.

For conservation plan, click here

For fact sheet, click here

The boundaries of this IBA were slightly expanded in 2013 to fully include forested areas that ranked in the top 10% of forest blocks in BCR 29 (Piedmont).

Ornithological Summary

250 species of birds have been identified at Muddy Run since 1973. There are several features that make this area unique. Among them are (1) the stretch of river that remains ice-free because of turbulance created by the Muddy Run Power Plant; (2) the heavily wooded river hills; (3) the fluctuating levels of the pumped-storage reservoir; and (4) the old-field habitat found in the project area. Nesting Orchard Orioles and Northern Orioles have been recorded from May through August, and Cedar Waxwings in all seasons. Blue Grosbeaks are recorded breeders. The wooded areas of Muddy Run offer 23 species of warblers.

Conservation Issues

Conservation concerns include spraying herbicides and perticides. Warm season grasses are cut before June, which disprupts or destroys ground-nesting bird species.

There is currently a citizens's advisory committee organized by Muddy Run's owner, Philadelphia Electric Company. Delayed mowing and elimination or reduction of herbicides and pesticides would improve the overall breeding ecology of this site.

Land Use

Hydroelectric Project owned and operated by Philadelphia Electric Company.

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