Cottonwood (Drewsey) dam
Cottonwood (Drewsey)
Cottonwood (Drewsey) is a vital water resource infrastructure located in Harney County, Oregon, specifically designed for irrigation purposes along Cottonwood Creek. Built in 1967, this dam has a structural height of 83 feet and a storage capacity of 4500 acre-feet, serving a drainage area of 34.3 square miles. With a significant hazard potential, the dam's primary purpose is to provide water for agricultural activities in the region, making it a crucial asset for local government operations.
Managed by the Natural Resources Conservation Service, Cottonwood (Drewsey) features an uncontrolled spillway type with a maximum discharge capacity of 1450 cubic feet per second. Despite being rated as "Not Rated" in terms of condition assessment, the dam undergoes regular inspections every three years to ensure its structural integrity and safety. In the event of emergencies, the dam's emergency action plan readiness and risk management measures play a pivotal role in mitigating potential risks and safeguarding the surrounding areas from inundation.
The dam's location in Drewsey, Oregon, underlines its importance in water resource management within the region, with oversight provided by the Oregon Water Resources Department. With its moderate risk assessment rating of 3, Cottonwood (Drewsey) signifies the delicate balance between water supply for irrigation and the potential hazards associated with dam infrastructure. As a key component of the local water supply system, this dam serves as a critical link in ensuring sustainable water access for agricultural activities in the area.
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 Cottonwood (Drewsey) -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| North Fork Malheur River At Beulah Or | 1 cfs | → |
| Malheur R Be Warmsprings Res Nr Riverside Or | 0 cfs | → |
| John Day R At Blue Mtn Hot Spgs Nr Prairie City | 32 cfs | → |
| John Day River Near John Day | 68 cfs | → |
| Malheur River Below Nevada Dam Near Vale Or | 23 cfs | → |
| Owyhee River Below Owyhee Dam Or | 158 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Cottonwood (Drewsey).
Boat launches
- Beulah Reservoir Ramp
- North Warm Springs
- North Point Boat Launch 1
- North Point Boat Launch 2
- Warm Springs Reservoir South Boat Ramp
- Middle Warm Springs
Campgrounds
- Chukar Park
- Crane Crossing
- Crane Creek Campground
- Little Crane
- North Fork Malheur Campground
- North Fork Malheur
Track Cottonwood (Drewsey) 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 Cottonwood (Drewsey)
Where does the data for Cottonwood (Drewsey) 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 Cottonwood (Drewsey).