Lake Ilo Dam
Lake Ilo Dam is an earth dam located in Dunn County, North Dakota, built in 1937. It carries a High hazard potential classification and has a fair condition assessment.
About Lake Ilo Dam
The primary purpose of Lake Ilo Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Us Fish And Wildlife Service (federal). It impounds the Spring Creek near Dunn Center, Nd.
The dam stands 51 feet tall and stretches 1,715 feet across, creates a reservoir covering 990 acres, has a maximum storage capacity of 31,326 acre-feet, and collects water from a drainage area of 129 square miles. Completed in 1937, 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 fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 09/27/2017. That was 8 years ago, which is on the longer end for a high-hazard structure.
At 51 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 North Dakota 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 | North Dakota |
| County | Dunn |
| Nearest City | Dunn Center, Nd |
| River/Stream | Spring Creek |
| Coordinates | 47.34833, -102.64722 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 51 ft |
| Dam Height | 38 ft |
| Dam Length | 1,715 ft |
| Year Completed | 1937 (89 years old) |
Storage & Hydraulics
| NID Storage | 31,326 acre-ft |
| Max Storage | 31,326 acre-ft |
| Normal Storage | 5,147 acre-ft |
| Surface Area | 990 acres |
| Drainage Area | 129 sq mi |
| Max Discharge | 30,716 cfs |
Ownership & Safety
| Purpose | Recreation |
| Owner | US FISH AND WILDLIFE SERVICE |
| Owner Type | Federal |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 09/27/2017 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | ND00321 |
| Federal ID | ND00321 |
| More Info | State Dam Safety Program |