Duncan dam
Duncan
Duncan is a privately owned Earth dam located in Sheridan, Wyoming, along the Jennings Gulch river. Built in 1939 by designer Paul F. Anderson, this dam stands at a height of 33 feet and has a reservoir storage capacity of 59 acre-feet. Despite its low hazard potential, recent inspections have rated its condition as poor, highlighting the need for maintenance and potential repairs to ensure its long-term safety and functionality.
Situated in a picturesque setting with a surface area of 5 acres, Duncan serves as a vital water resource for the surrounding area. The dam's primary purpose, categorized as 'Other', underscores its importance in managing water flow and storage. Although currently in a state of disrepair, Duncan's historical significance and contribution to the local ecosystem make it a valuable asset that warrants attention and preservation efforts.
With Liz Cheney representing Congressional District 00, Wyoming, where Duncan is located, there is a clear opportunity for advocacy and support for the dam's restoration and upkeep. As water resource and climate enthusiasts, it is crucial to recognize the role of structures like Duncan in sustainable water management and to advocate for the necessary resources and interventions to safeguard these critical assets for future generations.
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 Duncan -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Piney Creek At Kearny | 113 cfs | → |
| Rock Creek Near Buffalo | 70 cfs | → |
| South Piney Creek At Willow Park | 0 cfs | → |
| Goose Creek Near Acme | 123 cfs | → |
| Tongue River At Monarch | 383 cfs | → |
| Prairie Dog Creek Near Acme | 19 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Duncan.
Campgrounds
- Washington Park - Sheridan
- Little Goose Campground
- Sheridan Koa
- Big Goose Campground
- Ranger Creek - Tongue
- Cross Creek Campground
Fishing spots
- Sheridan Fairgrounds Pond
- Lake Desmet
- Healy Lake
- Tie Hack Reservoir
- Upper Paintrock Fishing Site
- Tongue River Fishing Site
Paddle runs
- Bridge At Tongue River Canyon To Burgess Picnic Grounds
- Sf Tongue- Johnson Creek To Confluence With Nf Tongue
- White Creek
- Dry Medicine Lodge Creek
- Nf Tongue From Burgess Picnic Ground To Pole Creek
More reservoirs
Track Duncan 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 Duncan
Where does the data for Duncan 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 Duncan.