Leonard Thomas Reservoir dam
Leonard Thomas Reservoir
Leonard Thomas Reservoir, also known as Aspen, is a crucial water supply source located in Pitkin, Colorado. Built in 1964, this local government-owned reservoir serves the primary purpose of water supply, with a maximum storage capacity of 13 acre-feet. The dam, constructed with earth and stone core types, stands at a height of 19 feet and a length of 280 feet, providing a structural height of 21 feet.
With a significant hazard potential and a satisfactory condition assessment, Leonard Thomas Reservoir is subject to regular inspections and maintenance to ensure its safety and functionality. The reservoir's spillway type is uncontrolled, with a spillway width of 13 feet. In case of emergencies, the reservoir is equipped with two vertical lift outlet gates to manage water discharge. Overall, Leonard Thomas Reservoir plays a critical role in water resource management in the region, contributing to the local water supply infrastructure.
Situated along Castle Creek-OS, Leonard Thomas Reservoir is regulated by the Colorado Department of Water Resources (DWR) and falls under state jurisdiction for permitting, inspection, and enforcement. The reservoir has a normal storage capacity of 10 acre-feet and a maximum discharge capacity of 207 cubic feet per second. The risk assessment for Leonard Thomas Reservoir is moderate, with measures in place to manage potential risks and ensure the safety of the surrounding community. As a key water resource in the area, Leonard Thomas Reservoir showcases the importance of sustainable water management practices in the face of climate change and increasing water demands.
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 Leonard Thomas Reservoir -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Roaring Fork River Near Aspen | 130 cfs | → |
| Hunter Creek Near Aspen | 8 cfs | → |
| Roaring Fork River Ab Difficult C Nr Aspen | 51 cfs | → |
| Roaring Fork River Ab Lost Man C | · | → |
| Fryingpan River Near Ruedi | 117 cfs | → |
| Fryingpan River At Meredith | 201 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Leonard Thomas Reservoir.
Boat launches
- Wingo Boat Ramp
- Boat Ramp Road Gunnison County
- Homestake Reservoir Boat Ramp Day Use Area
- Turquoise Lake Trail Lake County
- Matchless Boating Site
- Red Rooster Boating Site
Campgrounds
- Silver Bar
- Silver Bar Campground
- Silver Bell
- Silver Bell Campground
- Difficult
- Difficult Campground And Group Campground
Fishing spots
- Lost Man Reservoir
- Ruedi Reservoir
- Grizzly Reservoir
- Fryingpan River
- Emerald Lake (Crested Butte)
- Christine Lake
Track Leonard Thomas Reservoir 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 Leonard Thomas Reservoir
Where does the data for Leonard Thomas Reservoir 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 Significant 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 Leonard Thomas Reservoir.