Twin Lakes Dam
Twin Lakes
Twin Lakes, located in Vilas County, Wisconsin, is a public utility hydroelectric facility with a primary purpose of flood risk reduction and hydroelectric power generation. The dam, completed in 1908, is a gravity structure measuring 10 feet in height and 157 feet in length, with a NID storage capacity of 93,526 acre-feet. The dam is equipped with a controlled spillway and a Tainter (radial) outlet gate to manage water flow and ensure safety.
Managed by the Federal Energy Regulatory Commission, Twin Lakes has a low hazard potential and a very high risk assessment rating due to its critical role in flood control and power generation. Although the condition assessment is not available, regular inspections are conducted every three years to ensure the dam's structural integrity and operational efficiency. The emergency action plan (EAP) for the dam was last revised in December 2018 to meet guidelines and enhance emergency preparedness.
With its picturesque location in Eagle River and important role in water resource management, Twin Lakes is a vital asset for the surrounding community and ecosystem. Climate and water resource enthusiasts can appreciate the engineering and environmental significance of this historic dam, which continues to play a crucial role in safeguarding the local area from flooding and providing clean energy through hydroelectric power generation.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Twin Lakes -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Muskellunge Ck-Muskellunge L Otl-Nr Eagle River | 2 cfs | → |
| Muskellunge Creek Near St. Germain | 9 cfs | → |
| Cisco Branch Ontonagon R At Cisco Lake Outlet | 1 cfs | → |
| Allequash Creek Site 3 Near Boulder Junction | 4 cfs | → |
| Wisconsin River @ Rainbow Lake Nr Lake Tomahawk | 413 cfs | → |
| Stevenson Creek At Cth M Nr Boulder Junction | 2 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Twin Lakes .
Boat launches
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Campgrounds
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Fishing spots
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River runs
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About Twin Lakes
Where does the data for Twin Lakes come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the Low hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card below for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.