Granby Dike 1 dam
Granby Dike 1
Granby Dike 1, located in Grand County, Colorado, is a federally owned earth dam that serves multiple purposes, including hydroelectric power generation and irrigation. Completed in 1950, this impressive structure stands at a height of 98 feet and spans a length of 2170 feet, with a maximum storage capacity of 539,760 acre-feet. The dam is situated on the Colorado River and is regulated by the Bureau of Reclamation, with regular inspections and enforcement measures in place to ensure its safety and functionality.
With a high hazard potential and a very high risk assessment rating, Granby Dike 1 is a critical piece of infrastructure that requires careful monitoring and management. The dam features a controlled spillway with a width of 40 feet and has a maximum discharge capacity of 12,000 cubic feet per second. In the event of an emergency, it is essential to have an Emergency Action Plan (EAP) in place, although specific details about its preparation and guidelines adherence are not available at this time. Overall, Granby Dike 1 is a key component of the water resource system in Colorado, playing a vital role in water storage, flood control, and power generation in the region.
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 Granby Dike 1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Colorado River Below Lake Granby | 103 cfs | → |
| Colorado River Near Granby | 77 cfs | → |
| Willow Creek Below Willow Creek Reservoir | 7 cfs | → |
| Colorado River Bl Shadow Mountain Reservoir | 233 cfs | → |
| Colorado River At Windy Gap | 149 cfs | → |
| Grand Lake Outlet Blw Chipmunk Ln At Grand Lk | 212 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Granby Dike 1.
Boat launches
- Cr 6 Grand County
- Us 34 Grand County
- Willow Creek Boating Site
- Grand County
- Hilltop Boating Site
- Boat Launch Grand Lake
Campgrounds
Fishing spots
- Granby Lake
- Willow Creek Fishing Site
- Shadow Mountain Reservoir
- Monarch Lake
- Watanga Lake - Ipwa
- Long Lake (Hell Canyon) - Ipwa
Paddle runs
- Headwaters To Ends 0.5 Miles Away From Trail Ridge Road
- Headwaters To Ends 0.5 Miles Upstream From End Of County Hwy 115
- Begins 0.5 Miles Upstream From End Of County Hwy 115 To Eastern Boundary Of Rocky Mountain National Park
- 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
- Begins 0.5 Miles Upstream From End Of Fern Lake Road To Eastern Boundary Of Rocky Mountain National Park
Track Granby Dike 1 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 Granby Dike 1
Where does the data for Granby Dike 1 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 Granby Dike 1.