Bennettsen Lake Dam dam
Bennettsen Lake Dam
Bennettsen Lake Dam, located in Mason, Washington, is a state-owned structure that serves the primary purpose of recreation. Completed in 1971, this earth dam stands at a hydraulic height of 11 feet, with a structural height of 6 feet and a length of 150 feet. The dam has a storage capacity of 270 acre-feet, with a normal storage level of 253 acre-feet, covering a surface area of 28 acres and draining a small watershed of 0.18 square miles.
Situated on the Tr-Tahuya River, the Bennettsen Lake Dam poses a low hazard potential and is not currently rated for its condition. Although last inspected in June 2001, the dam is regulated and inspected by the Washington Department of Ecology, ensuring compliance with state safety and maintenance standards. Despite its low risk profile, the dam lacks an Emergency Action Plan (EAP) and other risk management measures, highlighting the need for continued monitoring and preparedness in the face of potential climate-related challenges.
With its picturesque location and recreational opportunities, Bennettsen Lake Dam stands as a vital water resource for the community, offering a serene setting for outdoor activities. As climate change impacts water resources across the region, the maintenance and safety of dams like Bennettsen Lake become increasingly important in ensuring the resilience of water infrastructure and the protection of surrounding ecosystems.
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 Bennettsen Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Huge Creek Near Wauna | 7 cfs | → |
| Skokomish River Near Potlatch | 512 cfs | → |
| Duckabush River Near Brinnon | 155 cfs | → |
| North Fork Skokomish River Near Potlatch | 254 cfs | → |
| South Fork Skokomish River Near Union | 172 cfs | → |
| Nf Skokomish R Bl Staircase Rpds Nr Hoodsport | 118 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Bennettsen Lake Dam.
Boat launches
- Lorna Lee Way Mason County
- Northeast State Highway 300 Mason County
- 3041 E Mason Lake Dr E, Grapeview, Wa 98546
- Highway 3 18560, Belfair
- Highway 106 5101, Union
- Wright Bliss Road Nw Pierce County
Campgrounds
- Tahuya River Horse Camp
- Belfair State Park
- Camp Hahobas
- Twanoh State Park
- Green Mountain Horse Camp
- Hamma Hamma Cabin
Paddle runs
- Brothers Wilderness Boundary To Olympic Nf Boundary
- Olympic Nf/Olympic Np Bounary To Brothers Wilderness Boundary
- Headwaters- Includes All Tributaries To Confluence With North Fork Skokomish River
- Headwaters- Includes All Tributaries To Confluence With Duckabush River
- Headwaters To Confluence With North Fork Skokomish River
- Headwaters To Southern Boundary Of Olympic National Park
Track Bennettsen 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 Bennettsen Lake Dam
Where does the data for Bennettsen 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 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 Bennettsen Lake Dam.