Delton dam
Delton
Delton, also known as Mirror Lake, is a gravity dam located in Lake Delton, Wisconsin, with a primary purpose of recreation. Completed in 1931, this structure boasts a height of 19 feet and a hydraulic height of 14 feet, with a storage capacity of 1280 acre-feet. The dam spans 150 feet in length and is situated on Dell Creek, serving as a controlled spillway with a width of 127 feet.
Despite its age, Delton remains in fair condition with a low hazard potential, as indicated by a recent assessment in October 2020. The dam has a very high risk assessment rating of 1, highlighting the importance of ongoing monitoring and maintenance. While it is not under the jurisdiction of the US Army Corps of Engineers, the Wisconsin Department of Natural Resources regulates, inspects, and enforces compliance with state permitting requirements to ensure the safety and integrity of the structure for both recreational and environmental purposes. Overall, Delton stands as a significant water resource in the area, contributing to the local landscape and providing opportunities for outdoor activities.
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 Delton -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Wisconsin River Near Wisconsin Dells | 9,040 cfs | → |
| Baraboo River Near Baraboo | 385 cfs | → |
| Lemonweir River At New Lisbon | 326 cfs | → |
| Black Earth Creek At Black Earth | 51 cfs | → |
| Brewery Creek-Upstream Site-At Cross Plains | 2 cfs | → |
| Yellow River At Necedah | 253 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Delton.
Boat launches
- Lake Delton -- Canyon Drive
- Lake Blass -- Access
- Mirror Lake -- State Park - E Side Of Lake
- Dam Road 11, Lake Delton
- County Highway A Lake Delton
- Newport Park
Campgrounds
- Cliffwood Campground
- Sandstone Ridge Campground
- Bluewater Bay Campground
- Mirror Lake State Park
- American Resport And Campground
- Dell Boo Campground
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 Delton 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 Delton
Where does the data for Delton 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 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 Delton.