Pennsylvania Dams
1,481 dams tracked by the National Inventory of Dams
Total Dams
1,481
High Hazard
780
52.7%
Poor / Unsatisfactory
215
Average Age
80 yrs
Hazard Classification
High780 (52.7%)
Significant310 (20.9%)
Low378 (25.5%)
Condition Assessment
Satisfactory415 (28.0%)
Fair547 (36.9%)
Poor / Unsatisfactory215 (14.5%)
Not Rated304 (20.5%)
Federal
57
State
152
Local
351
Private
911
Tallest Dams
- Harmar Refuse Bank410 ft
- Little Blue Run400 ft
- Cumberland No. 1 Slurry Pond 1380 ft
- Cumberland No. 2 Slurry Pond370 ft
- Bailey Mine Area No. 3 Slurry337 ft
High Hazard Dams
Poor Condition Dams
- Little Pine CreekPoor
- North ForkPoor
- DehartPoor
- Mill RunPoor
- West Newton SludgeUnsatisfactory
All Dams in Pennsylvania
Showing 851–875 of 1,481
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| Maple Creek Slurry Pond 1 Washington County | 120 | 1973 | High | Satisfactory |
| Maple Creek Slurry Pond No 2 - A Washington County | 91 | 1978 | High | Satisfactory |
| Maple Lake Lackawanna County | 23 | 1893 | High | Fair |
| Maple Lake Pike County | 35 | 1972 | High | Fair |
| Maple Lake Sullivan County | 14 | 1954 | High | Fair |
| Marcel Lake Pike County | 23 | 1961 | High | Fair |
| Marquette Lake Lebanon County | 27 | 1943 | High | Poor |
| Marshall Lake Monroe County | 9 | 1904 | High | Unsatisfactory |
| Marshall Lake Allegheny County | 14 | — | Low | Fair |
| Marshall Reservoir No. 2 Washington County | 37 | 1928 | Significant | Satisfactory |
| Marsh Creek Reservoir (Pa-437) Chester County | 90 | 1973 | High | Fair |
| Marsh Run Pond York County | 9 | 1960 | Undetermined | Not Rated |
| Marshwood Lackawanna County | 14 | 1927 | High | Fair |
| Martindale Cambria County | 22 | 1910 | High | Poor |
| Martin (Pa-419) Wayne County | 29 | 1960 | High | Poor |
| Martins Montgomery County | 23 | 1886 | High | Fair |
| Martins Creek (Pa-467) Susquehanna County | 52 | 1967 | High | Fair |
| Martins Creek Ses Ash Basin No 4 Northampton County | 43 | 1989 | Significant | Fair |
| Mathay (Pa-459) Mercer County | 22 | 1962 | High | Fair |
| Mathies Mine Refuse Area Pond #2 Washington County | 300 | 1982 | High | Fair |
| Mathies Sediment Pond No 5 Washington County | 33 | 1982 | Significant | Fair |
| Mauch Chunk Lake (Pa-462) Carbon County | 55 | 1971 | High | Fair |
| Maxwell Locks and Dam Washington County | 56 | 1964 | Significant | Not Available |
| Mcconnell Lake Pike County | 16 | 1957 | Significant | Fair |
| Mcdonaldton Somerset County | 16 | 1911 | Significant | Fair |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.