Sixty Seven dam
Sixty Seven
Sixty Seven is a privately owned irrigation dam located in Sublette, Wyoming, specifically in the city of Big Piney. Constructed in 1942 by David P. Miller, this Earth-type dam stands at a height of 32 feet and has a hydraulic height of 27 feet. It serves the primary purpose of irrigation for the surrounding area, with a storage capacity of 7,090 acre-feet and a normal storage level of 6,087 acre-feet. The dam spans 956 feet in length and has a surface area of 371 acres, drawing water from Spring Creek offstream.
Despite its age, Sixty Seven is regulated and inspected by the State of Wyoming, with the State Engineer's Office overseeing its operation, maintenance, and enforcement. The dam has a spillway width of 10 feet and a maximum discharge of 400 cubic feet per second, with one valve serving as its outlet gate. With a high hazard potential and moderate risk assessment, Sixty Seven poses a significant challenge for risk management and emergency preparedness. The dam's last inspection was conducted in August 2020, highlighting the importance of regular monitoring and maintenance to ensure its safety and efficiency in the face of changing climate conditions.
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 Sixty Seven -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| New Fork River Near Big Piney | 996 cfs | → |
| Green River Near La Barge | 1,420 cfs | → |
| Green River At Warren Bridge | 1,100 cfs | → |
| Fontenelle C Nr Herschler Ranch | 88 cfs | → |
| Pine Creek Above Fremont Lake | 968 cfs | → |
| Smiths Fork Near Border | 359 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Sixty Seven.
Boat launches
- New Fork Campground Boat Launch
- New Fork Campground Boat Takeout
- Fremont Lake Boat Ramp
- Names Hill Boat Launch
- Green River Access Site 1 Boat Ramp
- Green River Access Site 2 Boat Launch
Campgrounds
- Sacajawea
- Snyder Guard Station
- New Fork Campground
- New Fork River
- New Fork Campsite 1
- New Fork Campsite 2
Fishing spots
Paddle runs
Track Sixty Seven 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 Sixty Seven
Where does the data for Sixty Seven 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 Sixty Seven.