Lake Jefferson
High HazardUnsatisfactory ConditionEmergency Action Plan: Yes
Location
| State | New York |
| County | Sullivan |
| Nearest City | Jeffersonville |
| River/Stream | East Branch Callicoon Creek |
| Coordinates | 41.77740, -74.92530 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 22 ft |
| Dam Height | 22 ft |
| Dam Length | 220 ft |
| Year Completed | 1927 (99 years old) |
Storage & Hydraulics
| NID Storage | 350 acre-ft |
| Max Storage | 350 acre-ft |
| Normal Storage | 350 acre-ft |
| Surface Area | 30 acres |
| Drainage Area | 30 sq mi |
| Max Discharge | 6,865 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | Barbara A. & Kevin J. Gref |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Unsatisfactory |
| Last Inspection | 06/05/2025 |
| Emergency Action Plan | Yes |