Zimmerman Lake dam
Zimmerman Lake
Zimmerman Lake in Larimer County, Colorado, is a state-regulated earth dam built in 1913 for the primary purpose of creating a fish and wildlife pond. The dam stands at a height of 10 feet and has a length of 600 feet, with a storage capacity of 238 acre-feet. The lake covers an area of 20 acres and is fed by the Joe Wright Creek. Despite its low hazard potential, the dam's condition was assessed as unsatisfactory during the last inspection in July 2013.
Located just 42 miles from Fort Collins, Zimmerman Lake offers a serene setting for outdoor enthusiasts and nature lovers. Its controlled spillway, with a width of 11 feet, helps manage the lake's water levels, while the moderate risk assessment rating indicates a need for ongoing monitoring and risk management measures. The dam is subject to state regulation, permitting, inspection, and enforcement by the Colorado Division of Water Resources, ensuring the safety and integrity of the structure for both recreational and environmental purposes.
With its picturesque surroundings and crucial role in supporting local wildlife, Zimmerman Lake serves as a vital water resource in the region. Whether it's for fishing, wildlife observation, or simply enjoying the beauty of the outdoors, this historic lake continues to be a cherished destination for those passionate about water resources and climate conservation 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 Zimmerman Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Joe Wright Creek Above Joe Wright Reservoir | 3 cfs | → |
| Joe Wright Creek Below Joe Wright Reservoir | 30 cfs | → |
| Michigan River Near Cameron Pass | 8 cfs | → |
| Grand River Ditch At La Poudre Pass | 118 cfs | → |
| Colorado R Below Baker Gulch | 192 cfs | → |
| Illinois Creek Near Rand | 63 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Zimmerman Lake.
Boat launches
- Chambers Lake Boating Site
- Hilltop Boating Site
- Boat Launch Grand Lake
- Grand County
- Dowdy Drive 2, Larimer County
- Nowata Drive 597, Larimer County
Campgrounds
- The Crags - State Forest State Park
- Chambers Lake
- Chambers Lake Campground
- Grandview Campground
- Bockman - State Forest State Park
- Long Draw Campground
Fishing spots
- Zimmerman Lake
- Joe Wright Reservoir
- Joe Wright Fishing Site
- Trap Lake
- Chambers Lake
- Barnes Meadow Reservoir
Paddle runs
- Big South
- Begins 0.5 Miles Away From Trail Ridge Road To Ends Where River Segment Exits Rocky Mountain National Park
- Headwaters To Ends 0.5 Miles Upstream From End Of Fern Lake Road
- Spencer Heights
- Headwaters To Fan Lake
- Headwaters To Boundary Of Rocky Mountain National Park
More reservoirs
Track Zimmerman Lake 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 Zimmerman Lake
Where does the data for Zimmerman Lake 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 Zimmerman Lake.