Bismark Lake dam
Bismark Lake
Located in the picturesque NORBECK WILDLIFE PRESERVE in Custer, South Dakota, Bismark Lake is a serene body of water fed by BISMARK CREEK. Managed by the USDA Forest Service, this Federal-owned recreational spot offers a tranquil escape for nature enthusiasts and climate advocates alike. The Earth-type dam, completed in 1937, stands at 38 feet high and stores 626 acre-feet of water for fish and wildlife purposes, as well as recreational activities.
With a maximum storage capacity of 626 acre-feet and a normal storage level of 297 acre-feet, Bismark Lake is a vital resource for the surrounding ecosystem. The dam's spillway, uncontrolled with a width of 30 feet, ensures the safe release of excess water during periods of high discharge, with a maximum capacity of 2087 cubic feet per second. Despite being rated as having a high hazard potential, the dam's condition remains unassessed as of the last inspection in 2019, presenting a moderate risk that requires ongoing monitoring and management measures.
As a key site for outdoor recreation and conservation efforts, Bismark Lake serves as a valuable asset in the preservation of South Dakota's water resources and natural environment. Its significance extends beyond its physical structure, embodying a harmonious balance between human enjoyment and ecological stewardship in the face of climate challenges.
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 Bismark Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Grace Coolidge Cr Nr Game Lodge Nr Custer Sd | 0 cfs | → |
| French Cr Above Fairburn Sd | 2 cfs | → |
| Battle Cr Near Keystone Sd | 1 cfs | → |
| Beaver Creek Near Pringle | 5 cfs | → |
| Battle Cr At Hermosa Sd | 3 cfs | → |
| Spring Cr Near Keystone Sd | 1 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Bismark Lake.
Boat launches
- Bismark Lake Road Custer County
- Calvert Road Pennington County
- Sheridan Lake Road 16451, Rapid City
- Pennington County
- Fsr 450 Pennington County
- Jenney Gulch Picnic Area Fishing Access
Campgrounds
- Bismarck Lake
- Bismark Lake Campground
- Stockade Lake N - Custer State Park
- Stockade Lake North Campground
- Stockade Lake Campground South
- Stockade Lake S - Custer State Park
Track Bismark Lake 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 Bismark Lake
Where does the data for Bismark Lake 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 Bismark Lake.