Swift No. 1 dam
Swift No. 1
Swift No. 1 is a private hydroelectric dam located in Cougar, Washington, along the Lewis River. Completed in 1958, this earth dam stands at a height of 412 feet and has a maximum storage capacity of 755,500 acre-feet. With a surface area of 4,620 acres and a drainage area of 477 square miles, Swift No. 1 plays a crucial role in flood risk reduction, hydroelectric power generation, and recreational activities in the region.
Managed by the Federal Energy Regulatory Commission, Swift No. 1 has a controlled spillway with a width of 100 feet and two Tainter radial gates for regulated water discharge. The dam's hazard potential is rated as high, with a very high risk assessment score. While the condition assessment is not available, the emergency action plan was last revised in February 2021, highlighting the importance of preparedness and risk management for such critical infrastructure.
Overall, Swift No. 1 serves as a significant water resource and climate resilience asset in Skamania County, Washington. Its strategic location and design contribute to managing water resources efficiently, generating clean energy, and providing recreational opportunities while addressing potential hazards and risks associated with dam operations. For water resource and climate enthusiasts, Swift No. 1 offers a compelling case study of sustainable water infrastructure development and management in the Pacific Northwest.
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 Swift No. 1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Speelyai Creek Near Cougar | 31 cfs | → |
| Muddy Creek Below Clear Creek Near Cougar | 334 cfs | → |
| Lewis River Above Muddy River Near Cougar | 665 cfs | → |
| Canyon Creek Near Amboy | 163 cfs | → |
| Lewis River At Ariel | 2,820 cfs | → |
| East Fork Lewis River Near Heisson | 244 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Swift No. 1.
Boat launches
- Forest Road 81 Cowlitz County
- Frasier Road 499, Ariel
- Yale Bridge Road Clark County
- Woodland Park Road Cowlitz County
- Coldwater Lake Picnic And Boating Site
- Spirit Lake Highway Cowlitz County
Campgrounds
Paddle runs
- Nw1/4 Of Sec 9, T5n, R6e To Ne1/4 Of Sec 6, T5n, R5e
- Gifford Pinchot Nf Boundary To Maximum Pool Of Swift Reservoir In Nw1/4 Of Sec 35, T7n, R6e
- Confluence With Smith Creek To Confluence With Lewis River
- Mt. Adams Wilderness Boundary To Gifford Pinchot Nf Boundary
- Middle Of Sec 19, T8n, R7e To Confluence With Muddy River In Se1/4 Of Sec 1, T7n, R6e
- (Upper Muddy Segment) Headwaters In Se1/4 Of Sec 10, T8n, R5e To Conflence With Smith Creek
Track Swift No. 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 Swift No. 1
Where does the data for Swift No. 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 Swift No. 1.