Lower Lake Nemahbin is a gravity dam located in Waukesha County, Wisconsin, built in 1934. It carries a Low hazard potential classification and has a fair condition assessment.
Dam profile
NID height · 8 ft8 ft tall and 200 ft long. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic concrete gravity section and the water level is illustrative.
About Lower Lake Nemahbin
The primary purpose of Lower Lake Nemahbin is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Village of Summit (local government). It impounds the Bark near Dousman.
The dam stands 8 feet tall and stretches 200 feet across, creates a reservoir covering 268 acres, has a maximum storage capacity of 1,880 acre-feet, and collects water from a drainage area of 54 square miles. Completed in 1934, the structure is well-established, with more than 75 years of service.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. The most recent inspection on record was 08/05/2009. That was over 17 years ago.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Wisconsin |
| County | Waukesha |
| Nearest City | Dousman |
| River/Stream | Bark |
| Coordinates | 43.05616, -88.44216 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 8 ft |
| Dam Height | 8 ft |
| Dam Length | 200 ft |
| Year Completed | 1934 (92 years old) |
Storage & Hydraulics
| NID Storage | 1,880 acre-ft |
| Max Storage | 1,880 acre-ft |
| Normal Storage | 270 acre-ft |
| Surface Area | 268 acres |
| Drainage Area | 54 sq mi |
| Max Discharge | 1,050 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | Village of Summit |
| Owner Type | Local Government |
| Hazard Classification | Low |
| Condition Assessment | Fair |
| Last Inspection | 08/05/2009 |
| Emergency Action Plan | No |
Identifiers
| NID ID | WI01120 |
| Federal ID | WI01120 |
| More Info | State Dam Safety Program |