Long Lake
Long Lake is a gravity dam located in Washburn County, Wisconsin, built in 1913. It carries a High hazard potential classification and has a fair condition assessment.
About Long Lake
The primary purpose of Long Lake is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Washburn County (local government). It impounds the Brill near Brill.
The dam stands 15 feet tall and stretches 575 feet across, creates a reservoir covering 3,290 acres, has a maximum storage capacity of 35,000 acre-feet, and collects water from a drainage area of 82 square miles. Completed in 1913, the structure is over a century 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 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 05/07/2020.
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 Wisconsin 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 | Wisconsin |
| County | Washburn |
| Nearest City | Brill |
| River/Stream | Brill |
| Coordinates | 45.66801, -91.68066 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 15 ft |
| Dam Height | 15 ft |
| Dam Length | 575 ft |
| Year Completed | 1913 (113 years old) |
Storage & Hydraulics
| NID Storage | 35,000 acre-ft |
| Max Storage | 35,000 acre-ft |
| Normal Storage | 15,000 acre-ft |
| Surface Area | 3,290 acres |
| Drainage Area | 82 sq mi |
| Max Discharge | 2,660 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Recreation |
| Owner | Washburn County |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 05/07/2020 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | WI00325 |
| Federal ID | WI00325 |
| More Info | State Dam Safety Program |