Prairie Du Sac dam
Prairie Du Sac
Prairie Du Sac, located in Sauk County, Wisconsin, is home to a historic hydroelectric dam on the Wisconsin River. Built in 1914 by MEAD & SEASTONE, this gravity dam stands at a height of 50 feet and has a hydraulic height of 38 feet. With a storage capacity of 193,200 acre-feet and a normal storage level of 119,950 acre-feet, the dam serves as a vital source of hydroelectric power in the region.
Managed by a public utility, Prairie Du Sac dam is regulated by the Federal Energy Regulatory Commission (FERC) and is used primarily for hydroelectric purposes. The dam has a controlled spillway with a width of 820 feet and is equipped with 41 Tainter (radial) outlet gates. With a high hazard potential and very high risk assessment rating, the dam plays a crucial role in water resource management and climate resilience efforts in the area.
Despite its age, Prairie Du Sac dam remains a key infrastructure asset, providing essential flood control, water storage, and renewable energy generation capabilities. As climate change continues to impact water resources, the dam's strategic location and design make it a critical component of the region's adaptive capacity and sustainable development goals, ensuring the resilience of local communities in the face of a changing climate.
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.
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 Prairie Du Sac -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Black Earth Creek At Black Earth | 51 cfs | → |
| Baraboo River Near Baraboo | 385 cfs | → |
| Brewery Creek-Upstream Site-At Cross Plains | 2 cfs | → |
| Pheasant Branch At Airport Road Nr Middleton | 2 cfs | → |
| Pheasant Branch At Middleton | 3 cfs | → |
| Spring Creek Near Waunakee | 8 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Prairie Du Sac .
Boat launches
- Vfw Drive 490, Village Of Prairie Du Sac
- Wisconsin River -- Sauk City - Access Off Water Street
- Wisconsin River -- Access At Sauk City Off Hwy 12
- Lake Wisconsin -- Access - Summer Oaks Resort Off Highway 78
- Fish Lake County Park Boat Ramp
- Lake Wisconsin -- Access - Lake Drive Off Highway 188
Campgrounds
- Vfw Campground
- Cedar Hills Campground
- Devil’S Lake State Park Campgrounds
- Springfield Hill Dca
- Eastern Lodi Marsh Dca
- Andersen Preserve Dca
Paddle runs
- Honey Creek (County Road Y On The Southern Bank) To The State Route 130 Highway Bridge Crossing At Lone Rock
- Lone Rock To The Confluence Of The Green And Wisconsin Rivers
More reservoirs
Track Prairie Du Sac in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Prairie Du Sac
Where does the data for Prairie Du Sac 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 High 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 above 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.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Prairie Du Sac .