Cedar Way Stormwater Detention Dam dam
Cedar Way Stormwater Detention Dam
The Cedar Way Stormwater Detention Dam, located within Mountlake Terrace in Snohomish, Washington, serves as a crucial infrastructure for flood risk reduction along Lyons Creek. Built in 1985, this earth dam with stone core stands at a hydraulic height of 30 feet and a structural height of 22 feet, providing a storage capacity of 40 acre-feet and a maximum discharge of 860 cubic feet per second. With a surface area of 3 acres and a drainage area of 1.63 square miles, this dam plays a vital role in managing stormwater runoff and reducing the risk of flooding in the surrounding area.
Managed by the local government and regulated by the Washington Department of Ecology, the Cedar Way Stormwater Detention Dam undergoes regular inspections to ensure its structural integrity and functionality. Despite its high hazard potential, the dam has been assessed to be in satisfactory condition, meeting safety standards and guidelines. The emergency action plan (EAP) for the dam was last revised in 2010, reflecting the commitment to preparedness and risk management in case of any unforeseen events. As a key component in the flood risk reduction strategy, this dam showcases the importance of sustainable water resource management and climate resilience efforts in the region.
Overall, the Cedar Way Stormwater Detention Dam stands as a testament to the collaborative efforts between local government agencies and regulatory bodies in safeguarding communities against the impacts of extreme weather events and climate change. By providing essential flood risk reduction measures and storage capacity for stormwater runoff, this dam plays a crucial role in ensuring the safety and well-being of residents in the surrounding area. With continued inspections, maintenance, and emergency preparedness measures in place, the Cedar Way Dam exemplifies best practices in water resource management and climate adaptation for a more resilient future.
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 Cedar Way Stormwater Detention Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Thornton Creek Near Seattle | 41 cfs | → |
| Snohomish River Near Monroe | 7,210 cfs | → |
| Mercer Creek Near Bellevue | 12 cfs | → |
| Pilchuck River Near Snohomish | 399 cfs | → |
| Snoqualmie River Near Carnation | 1,770 cfs | → |
| Issaquah Creek Near Mouth Near Issaquah | 55 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Cedar Way Stormwater Detention Dam.
Boat launches
- Beach Drive Northeast 17218, Lake Forest Park
- 68th Avenue Northeast 17181-17299, Kenmore
- East Shore Drive Snohomish County
- 14th Avenue Northwest Seattle
- Spu Public Boat Launch
- Island County
Campgrounds
- Fay Bainbridge State Park Campsite
- Fay Bainbridge State Park
- Cascade Marine Trail - Human Powered Boat Campsite
- Kitsap Memorial State Park
- Cascadia Marine Trail
- Wwta Campsite (Human Powered Boats Only)
Paddle runs
- Snoqualmie Falls To Plum's Landing
- Headwaters In Ne1/4 Of Sec 14, T29n, R10e To Confluence With Canyon Creek
- Confluence With Taylor River To Confluence With North Fork Snoqualmie River
- Wagner Bridge To Confluence With Middle Fork Snoqualmie River
- Canyon Creek To Confluence With North Fork Stillaguamish River
- Brothers Wilderness Boundary To Olympic Nf Boundary
Track Cedar Way Stormwater Detention 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 Cedar Way Stormwater Detention Dam
Where does the data for Cedar Way Stormwater Detention 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 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 Cedar Way Stormwater Detention Dam.