Three Mile dam
Three Mile
Located in Jackson County, Colorado, Three Mile is a privately owned dam that serves multiple purposes including irrigation, fire protection, stock water, and small fish pond maintenance. Built in 1934, this earth dam stands at a height of 16 feet and spans 346 feet in length, with a storage capacity of 64 acre-feet. Three Mile Creek is the primary source of water for this dam, with a maximum discharge capacity of 137 cubic feet per second.
Managed by the Colorado Division of Water Resources, Three Mile is classified as a low hazard dam with fair condition assessment. The dam has a controlled spillway width of 10 feet and is subject to regular inspections, with the last one conducted in October 2016. Despite being privately owned, the state regulatory agency oversees permitting, inspection, and enforcement to ensure the safety and integrity of the structure.
Water resource and climate enthusiasts will appreciate Three Mile's contribution to local irrigation and ecosystem maintenance in the region. With a moderate risk assessment rating, efforts to enhance risk management measures and emergency preparedness are ongoing to ensure the continued operation and safety of this vital water resource infrastructure in Colorado.
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 Three Mile -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| North Platte River Near Northgate | 366 cfs | → |
| Michigan River At Walden | 39 cfs | → |
| Encampment River Ab Hog Park Cr | 298 cfs | → |
| Laramie R Bl Pioneer Canal Nr Woods Landing | 1,010 cfs | → |
| Pioneer Canal Near Woods | 174 cfs | → |
| South Brush Creek Near Saratoga | 18 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Three Mile.
Boat launches
- Cowdrey Lake Rec Site Boat Ramp
- Cowdrey Lake Rec Site Boat Dock
- Bennett Creek Campground Boat Ramp
- Blm 3404 Carbon County
- Teal Lake Boating Site
- Tombstone Nature Trail Routt County
Campgrounds
- Six Mile Campground
- Six Mile
- Big Creek Lakes
- Big Creek Lakes Campground
- Cowdrey Lake Rec Site
- Pelton Creek Campground
Fishing spots
- Big Creek Lakes Day Use Area
- Big Creek Lake(Lower)
- Cowdrey Lake
- Big Creek Lake(Upper)
- Lake John
- North Platte River
Paddle runs
- South Sec Line, Sec 2, T11n, R80w To Co/Wy Stateline
- Northgate Canyon
- Big Creek
- Co/Wy Stateline To Douglas Creek
More reservoirs
Track Three Mile 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 Three Mile
Where does the data for Three Mile 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 Three Mile.