Long Hollow Dam
Maryland — Washington County — Potomac River-TR
Location
| State | Maryland |
| County | Washington |
| River | Potomac River-TR |
| Coordinates | 39.62609, -78.29366 |
Physical Characteristics
| NID Height | 25 ft |
| Dam Height | 25 ft |
| Dam Length | 200 ft |
| NID Storage | 16 acre-ft |
| Max Storage | 16 acre-ft |
| Surface Area | 4 acres |
Safety Classification
| Hazard Potential | Low |
| Condition Assessment | Poor |
| EAP Status | No |
| Last Inspection | May 10, 2016 |
| Inspection Frequency | — |
Dam Information
| Year Completed | 1940 |
| Primary Purpose | Recreation |
| Dam Type | Other |
| Owner Type | State |
| Owner | MD DNR-Public Lands, Engineering & Constr-Western |
| Other Name | Polly'S Pond, Poly Ponds |
Location Map
About This Dam Record
Dam safety data is maintained by the Army Corps of Engineers National Inventory of Dams (NID). High-hazard dams are those where failure could cause loss of life or major property damage downstream.