Crystal dam
Crystal
Crystal is a private dam located in Boulder, Colorado, along the St. Vrain Creek. Built in 1881, this earth dam stands at a height of 11 feet and has a length of 1140 feet, providing a storage capacity of 290 acre-feet. While its primary purpose is for recreation, Crystal also serves functions such as fire protection, irrigation, and stock or small fish pond support.
Maintained by the Colorado Department of Water Resources, Crystal is regulated and inspected regularly to ensure its structural integrity and safety. With a low hazard potential and a satisfactory condition assessment, this dam poses a moderate risk, reflecting the importance of ongoing risk management measures. In the event of an emergency, the dam is equipped with an uncontrolled spillway and has designated emergency contacts updated periodically.
For water resource and climate enthusiasts, Crystal presents an intriguing case study of a historic dam that continues to play a vital role in the local water infrastructure. From its construction in the late 19th century to its modern-day management practices, this dam offers insights into the intersection of water management, recreation, and environmental stewardship in the region. As the climate changes and water resources become increasingly important, understanding the maintenance and regulation of structures like Crystal is crucial for ensuring the safety and sustainability of our water systems.
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 Crystal -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| St. Vrain Creek At Lyons | 114 cfs | → |
| Left Hand Creek At Hover Road Near Longmont | 1 cfs | → |
| St. Vrain Creek Below Longmont | -999,999 cfs | → |
| St Vrain Cr Blw Boulder Cr At Hwy 119 Nr Longmont | 71 cfs | → |
| Boulder Creek At Mouth | 4 cfs | → |
| Big Thompson River At Loveland | 73 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Crystal.
Boat launches
- Lagerman Trail Boulder County
- Boat Ramp Larimer County
- Miramonte Road Boulder County
- Standley Lake Trail Westminster
- Brighton
- Adams County
Campgrounds
- Boulder County Fairground
- Carter Lake - South Side Campgrounds
- Union Reservoir
- Meadow Park
- North Pine Campground
- Carter Lake - North Side Campgrounds
Fishing spots
Track Crystal 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 Crystal
Where does the data for Crystal 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 Crystal.