Nielsen Dam C dam
Nielsen Dam C
Nielsen Dam C, located in Bothell, Washington, is a privately owned structure that serves the primary purpose of recreation. Built in 1973, this earth dam stands at a hydraulic height of 9 feet and has a length of 250 feet, providing a surface area of 12 acres for recreational activities. Despite its modest size, the dam has a high hazard potential and is currently in poor condition as assessed in 2018. The dam is situated on Tr-North Creek and is under the regulatory oversight of the Washington Department of Ecology, ensuring state permitting, inspection, and enforcement.
With a maximum storage capacity of 16 acre-feet and a normal storage capacity of 12 acre-feet, Nielsen Dam C plays a crucial role in managing water resources in the Snohomish County area. The dam's drainage area covers 0.15 square miles, with a maximum discharge rate of 4 cubic feet per second. However, the dam's poor condition and high hazard potential highlight the need for regular maintenance and potential risk management measures to ensure the safety of surrounding communities. Despite these challenges, the dam continues to attract visitors for recreational purposes, offering a serene escape in the midst of a bustling city.
As a significant structure in the region, Nielsen Dam C stands as a reminder of the delicate balance between water resource management and recreational opportunities. With its proximity to Bothell and the surrounding areas, the dam serves as a valuable asset for outdoor enthusiasts and nature lovers alike. However, ongoing efforts are required to address the dam's poor condition and high hazard potential, emphasizing the importance of proactive maintenance and risk management strategies to safeguard both the dam and the communities it serves.
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 Nielsen Dam C -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Thornton Creek Near Seattle | 41 cfs | → |
| Snohomish River Near Monroe | 2,090 cfs | → |
| Pilchuck River Near Snohomish | 83 cfs | → |
| Mercer Creek Near Bellevue | 12 cfs | → |
| Snoqualmie River Near Carnation | 799 cfs | → |
| Issaquah Creek Near Mouth Near Issaquah | 25 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Nielsen Dam C.
Boat launches
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Campgrounds
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Fishing spots
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River runs
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About Nielsen Dam C
Where does the data for Nielsen Dam C 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 below 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.
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.