Swanson dam
Swanson
The Swanson, Holm & Hemmah Group, also known as the Ernst Dam, is a privately owned structure located in Welch, Minnesota along the Cannon River. Built in 1959 by the USDA NRCS, this Earth-type dam stands at 30 feet tall and spans 421 feet in length. Its primary purpose is flood risk reduction, with a storage capacity of 23.4 acre-feet and a drainage area of 0.3 square miles.
Despite its low hazard potential, the Ernst Dam is currently in poor condition and last underwent inspection in April 2018. The dam has uncontrolled spillways and outlet gates, posing a moderate risk that necessitates regular inspections every 8 years. The State of Minnesota, through the MNDNR EWR agency, regulates and enforces the dam's operations to ensure public safety and environmental protection.
For water resource and climate enthusiasts, the Ernst Dam serves as a prime example of the critical infrastructure that plays a vital role in managing water resources and mitigating flood risks. Its location in Goodhue County highlights the importance of maintaining and improving dam structures to safeguard communities and ecosystems from potential hazards. As efforts to address climate change intensify, the resilience and effectiveness of structures like the Ernst Dam will be crucial in adapting to changing weather patterns and ensuring sustainable water management practices in the future.
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 Swanson -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Cannon River At Welch | 522 cfs | → |
| Vermillion River Near Empire | 49 cfs | → |
| Mississippi River At Red Wing | 18,800 cfs | → |
| Mississippi River Below L&D #2 At Hastings | 16,500 cfs | → |
| Mississippi River At Prescott | 20,600 cfs | → |
| Kinnickinnic River Near River Falls | 102 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Swanson.
Boat launches
- Mill Towns State Trail Dakota County
- Scout Ridge Road Goodhue County
- Gerlach Way Dakota County
- County Road 68 Goodhue County
- 190th Street Way Goodhue County
- Dakota County
Track Swanson 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 Swanson
Where does the data for Swanson 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 Swanson.