Cottonwood Creek Middle dam
Cottonwood Creek Middle
Cottonwood Creek Middle, also known as Cottonwood Detention Dam #2, is a crucial water resource infrastructure located in Boise, Idaho. Built in 1961, the dam serves the primary purpose of flood risk reduction along the Cottonwood Creek and Boise River. With a dam height of 20.4 feet and a hydraulic height of 15.4 feet, it plays a significant role in managing water flow and protecting the surrounding area from potential flood events.
Managed by the local government and regulated by the Idaho Department of Water Resources, Cottonwood Creek Middle has a fair condition assessment and a significant hazard potential. Despite its age, the dam continues to operate effectively, with regular inspections conducted to ensure its structural integrity and functionality. The dam's storage capacity of 40 acre-feet and drainage area of 16.6 square miles make it a critical component of the region's water management infrastructure, with a moderate risk assessment rating of 3.
Overall, Cottonwood Creek Middle stands as a vital piece of infrastructure in the region, providing essential flood risk reduction measures and safeguarding communities along the Cottonwood Creek and Boise River. Its strategic location and design exemplify the importance of water resource management in mitigating the impact of extreme weather events and climate change on local ecosystems and populations.
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 Cottonwood Creek Middle -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Cottonwood Creek Bel Fivemile Cr Nr Boise Id | 1 cfs | → |
| Boise River At Glenwood Bridge Nr Boise Id | 672 cfs | → |
| Boise River South Channel At Eagle Id | 437 cfs | → |
| Dry Creek Nr Eagle Id | 0 cfs | → |
| Eagle Drain At Eagle | 30 cfs | → |
| Mores Creek Ab Robie Creek Nr Arrowrock Dam Id | 61 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Cottonwood Creek Middle.
Boat launches
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Campgrounds
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Fishing spots
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River runs
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More reservoirs
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About Cottonwood Creek Middle
Where does the data for Cottonwood Creek Middle 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 below 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.
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.