Aldarra Pond Dfr1 dam
Aldarra Pond Dfr1
Aldarra Pond Dfr1, located in King County, Washington, is a privately owned earth dam constructed in 2001 for the primary purpose of flood risk reduction along Patterson Creek. The dam has a hydraulic height of 15 feet and a structural height of 14 feet, with a length of 1100 feet and a storage capacity of 53 acre-feet. Despite being non-federally owned and funded, the dam is regulated, permitted, inspected, and enforced by the Washington Department of Ecology, ensuring its compliance with state regulations.
This low-hazard dam has not been rated for condition assessment, and no emergency action plan (EAP) has been prepared or updated for it. While the risk assessment and management measures for the dam remain unspecified, it is reassuring to note that the dam's hazard potential is categorized as low. The last inspection conducted in August 2000 did not yield any specific condition assessment, indicating the need for ongoing monitoring and assessment to ensure the dam's continued effectiveness in flood risk reduction and safety for surrounding communities and ecosystems.
The Aldarra Pond Dfr1 serves as a vital infrastructure for flood risk management in the region, providing essential protection against potential flooding events along Patterson Creek. Its location in a high-risk flood zone underscores the importance of regular inspections, maintenance, and emergency preparedness to mitigate any risks associated with dam failure. As water resource and climate enthusiasts, it is essential to monitor the condition and management of dams like Aldarra Pond Dfr1 to safeguard water resources, ecosystems, and communities from the impacts of extreme weather events and climate change.
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 Aldarra Pond Dfr1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Raging River Near Fall City | 29 cfs | → |
| Issaquah Creek Near Mouth Near Issaquah | 41 cfs | → |
| Snoqualmie River Near Carnation | 1,390 cfs | → |
| Snoqualmie River Near Snoqualmie | 1,540 cfs | → |
| Issaquah Creek Near Hobart | 26 cfs | → |
| Tolt River Near Carnation | 257 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Aldarra Pond Dfr1.
Boat launches
- Northeast Tolt Hill Road 30348-30762, Carnation
- Lake Langlois Road Northeast King County
- Southeast Fish Hatchery Road 36495-37159, Fall City
- Lake Marcel Community Park
- West Lake Sammamish Parkway Northeast Redmond
- Sammamish River Trail Redmond
Campgrounds
Paddle runs
- Snoqualmie Falls To Plum's Landing
- Confluence With Taylor River To Confluence With North Fork Snoqualmie River
- Wagner Bridge To Confluence With Middle Fork Snoqualmie River
- Quartz Road To Confluence With Middle Fork Snoqualmie River
- Alpine Lakes Wilderness Boundary To Quartz Creek Road
- Confluence With Troublesome Creek To Confluence With South Fork Skykomish River
Track Aldarra Pond Dfr1 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 Aldarra Pond Dfr1
Where does the data for Aldarra Pond Dfr1 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 Aldarra Pond Dfr1.