Oswego Lake Dam dam
Oswego Lake Dam
Oswego Lake Dam is a private-owned structure located in Lake Oswego, Oregon, and serves multiple purposes including hydroelectric power generation and recreation. Completed in 1921, this concrete dam stands at 32 feet tall and has a structural height of 34 feet, with a storage capacity of 9,800 acre-feet. Situated on the Tualatin River offstream, it plays a significant role in managing water resources in the region.
With a maximum discharge capacity of 1,400 cubic feet per second, Oswego Lake Dam is a crucial component of the local watershed, providing flood control and water supply for various uses. Despite its age, the dam's hazard potential is rated as significant, highlighting the importance of regular inspections and maintenance to ensure its safety and effectiveness. The dam's emergency action plan status and risk management measures are currently not rated, underscoring the need for ongoing monitoring and preparedness in the face of changing climate conditions.
As a key feature in the water resource infrastructure of Clackamas County, Oregon, Oswego Lake Dam represents a blend of historical significance and modern functionality. Its role in hydroelectric power generation and recreational activities underscores the importance of balancing human needs with environmental stewardship in managing water resources. With a focus on safety, risk assessment, and emergency preparedness, the dam continues to play a vital role in the region's water management efforts amidst the challenges posed by a changing climate.
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 Oswego Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Tryon Creek Blw Nettle Creek | 1 cfs | → |
| Johnson Creek At Milwaukie | 21 cfs | → |
| Tualatin River At West Linn | 333 cfs | → |
| Fanno Creek At Durham | 8 cfs | → |
| Clackamas River Near Oregon City | 1,290 cfs | → |
| Fanno Creek At 56th Ave | 0 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Oswego Lake Dam.
Boat launches
- Willamette Greenway Lake Oswego
- Fielding Road 13060, Dunthorpe
- Cedaroak Boat Ramp West Linn
- Meldrum Bar Park Road Gladstone
- Waverly Marina
- Sellwood Riverfront Park
Campgrounds
Track Oswego Lake Dam 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 Oswego Lake Dam
Where does the data for Oswego Lake Dam 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 Oswego Lake Dam.