Lake Nessmuk (pa-601)
Lake Nessmuk (pa-601) is an earth dam located in Tioga County, Pennsylvania, built in 1968. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Lake Nessmuk (pa-601)
The primary purpose of Lake Nessmuk (pa-601) is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Pa Fish & Boat Commission (state). It impounds the Morris Branch Marsh Creek.
The dam stands 52 feet tall and stretches 870 feet across, creates a reservoir covering 60 acres, has a maximum storage capacity of 1,453 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1968, the structure is well into its service life at over 50 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 04/16/2020.
At 52 feet, this dam is taller than 93% of dams nationwide.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Pennsylvania dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Pennsylvania |
| County | Tioga |
| River/Stream | Morris Branch Marsh Creek |
| Coordinates | 41.73250, -77.29306 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 52 ft |
| Dam Height | 52 ft |
| Dam Length | 870 ft |
| Year Completed | 1968 (58 years old) |
Storage & Hydraulics
| NID Storage | 1,453 acre-ft |
| Max Storage | 1,453 acre-ft |
| Normal Storage | 572 acre-ft |
| Surface Area | 60 acres |
| Drainage Area | 1 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | PA FISH & BOAT COMMISSION |
| Owner Type | State |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 04/16/2020 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | PA00032 |
| Federal ID | PA00032 |
| More Info | State Dam Safety Program |