Onondaga Dam
Onondaga Dam is an earth dam located in Onondaga County, New York, built in 1949. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Onondaga Dam
The primary purpose of Onondaga Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Nys Dec Division Of Water (state). It impounds the Onondaga Creek near Onondaga Nation.
The dam stands 67 feet tall and stretches 2,050 feet across, creates a reservoir covering 2,500 acres, has a maximum storage capacity of 48,400 acre-feet, and collects water from a drainage area of 68 square miles. Completed in 1949, the structure is well-established, with more than 75 years of service.
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 10/23/2023.
At 67 feet, this dam is taller than 96% of all dams in the United States.
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 New York 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 | New York |
| County | Onondaga |
| Nearest City | Onondaga Nation |
| River/Stream | Onondaga Creek |
| Coordinates | 42.93111, -76.17528 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 67 ft |
| Dam Height | 67 ft |
| Dam Length | 2,050 ft |
| Year Completed | 1949 (77 years old) |
Storage & Hydraulics
| NID Storage | 48,400 acre-ft |
| Max Storage | 48,400 acre-ft |
| Surface Area | 2,500 acres |
| Drainage Area | 68 sq mi |
| Max Discharge | 82,350 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | NYS DEC DIVISION OF WATER |
| Owner Type | State |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 10/23/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | NY00794 |
| Federal ID | NY00794 |
| More Info | State Dam Safety Program |