In Lancaster County, Pennsylvania (PA). The map on this page is placed at the coordinates EIA files for the plant, which locate the site rather than any individual unit.

How big is Muddy Run?

1 GW of nameplate capacity across 8 units, as of the EIA-860M release for 2026-07.

EIA-860M names Constellation Power, Inc as the reporting entity. That is the operator of record on the survey, which is not always the ultimate owner.

Is this the same as Muddy Run LLC?

Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — Constellation Power, Inc here — not the project company that holds the asset. Project companies are commonly registered as an LLC carrying the plant's name, so a search for "Muddy Run LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.

Is Muddy Run still running?

EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.

Muddy Run

Muddy Run is a 1 GW pumped storage hydro plant in Lancaster County, Pennsylvania, operated by Constellation Power, Inc. EIA-860M lists 8 generating units here, inside PJM. Its units entered service between 1967 and 1968.

As of 2026-07 (inventory dated 2026-07-31) · EIA-860M Preliminary Monthly Electric Generator Inventory · eia.gov/…/july_generator2026.xlsx · eia.gov/…/eia860m

Nameplate capacity: 1,072 MW; 1,058 MW net summer
Generating units: 8
In service: 1967–1968
EIA plant ID: 3164

Where it is

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County: Lancaster County, Pennsylvania
Coordinates: 39.8076, -76.2993
Balancing authority: PJM
Sector: IPP Non-CHP

Units, technology and status

Operator of record: Constellation Power, Inc
Primary energy source: Pumped storage
Technologies: Hydroelectric Pumped Storage
Status: Operating

Every plant Constellation Power, Inc reports to EIA →

Muddy Run: FAQ

Where is Muddy Run?: In Lancaster County, Pennsylvania (PA). The map on this page is placed at the coordinates EIA files for the plant, which locate the site rather than any individual unit.
How big is Muddy Run?: 1 GW of nameplate capacity across 8 units, as of the EIA-860M release for 2026-07.
Who owns Muddy Run?: EIA-860M names Constellation Power, Inc as the reporting entity. That is the operator of record on the survey, which is not always the ultimate owner.
Is this the same as Muddy Run LLC?: Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — Constellation Power, Inc here — not the project company that holds the asset. Project companies are commonly registered as an LLC carrying the plant's name, so a search for "Muddy Run LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.
Is Muddy Run still running?: EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.