Mcginnis Evaporation dam
Mcginnis Evaporation
Mcginnis Evaporation, located in Sublette, Wyoming, is a privately owned earth dam structure designed by Joseph C. Lord in 1984. This offstream reservoir has a dam height of 24 feet and a length of 456 feet, providing a storage capacity of 64 acre-feet. With a surface area of 5 acres, the dam serves a primary purpose other than flood control or water supply, reflecting its unique role in managing water resources in the region.
Despite its low hazard potential and fair condition assessment, Mcginnis Evaporation poses a high risk due to its location and design characteristics. The dam lacks a spillway and outlet gates, potentially increasing the risk of flooding in the event of heavy rainfall or snowmelt. Regular inspections are conducted every 5 years to ensure the structure's integrity and safety, with the last assessment performed in May 2021.
For water resource and climate enthusiasts, Mcginnis Evaporation presents an intriguing case study in dam design and risk management. Understanding the complexities of this earth dam structure, its purpose, and the challenges it faces in a changing climate can provide valuable insights into the sustainable management of water resources in arid regions like Wyoming.
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 Mcginnis Evaporation -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Green River Near La Barge | 2,000 cfs | → |
| Fontenelle C Nr Herschler Ranch | 104 cfs | → |
| New Fork River Near Big Piney | 1,080 cfs | → |
| Hams Fork Below Pole Creek | 161 cfs | → |
| Green River Below Fontenelle Reservoir | 769 cfs | → |
| Smiths Fork Near Border | 406 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Mcginnis Evaporation.
Boat launches
- Names Hill Boat Launch
- Fontenelle Creek Boat Ramp
- Tail Race Campground Boat Launch
- Weeping Rock Campground Boat Launch
- New Fork Campground Boat Launch
- New Fork Campground Boat Takeout
Campgrounds
- Snyder Guard Station
- Scaler Guard Station
- Names Hill Primitive Camping Area
- Sacajawea
- Middle Piney Lake
- Middle Piney Lake Campground
Fishing spots
Track Mcginnis Evaporation 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 Mcginnis Evaporation
Where does the data for Mcginnis Evaporation 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 Mcginnis Evaporation.