South Ridge Stormwater Detention Dam dam
South Ridge Stormwater Detention Dam
The South Ridge Stormwater Detention Dam, located in Issaquah, Washington, is a private-owned structure designed by Concept Engineering to reduce flood risk along the North Fork Issaquah Creek. Completed in 2002, this earth dam stands at a hydraulic height of 10 feet and a length of 430 feet, with a storage capacity of 25 acre-feet. The dam serves as a crucial tool in managing stormwater runoff and protecting the surrounding community from potential flooding events.
With a hazard potential rated as high, the South Ridge Dam undergoes regular inspections to ensure its structural integrity and effectiveness in flood risk reduction. The condition assessment conducted in 2018 deemed the dam to be in satisfactory condition. The Washington Department of Ecology regulates the dam, and it is subject to state permitting, inspection, and enforcement to maintain compliance with safety standards. The dam's location in King County, Washington, adds to its significance in managing water resources and climate challenges in the region, highlighting the importance of sustainable infrastructure for resilient communities.
As a key component in the flood risk reduction strategy for the area, the South Ridge Stormwater Detention Dam plays a crucial role in safeguarding the community from potential inundation events. With its design focused on earth and stone materials, the dam efficiently manages stormwater runoff from a drainage area of 0.1 square miles, providing a storage capacity of 22 acre-feet under normal conditions. The dam's presence underscores the importance of proactive water resource management in mitigating the impacts of climate change and enhancing community resilience to extreme weather events.
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 South Ridge Stormwater Detention Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Issaquah Creek Near Mouth Near Issaquah | 44 cfs | → |
| Raging River Near Fall City | 33 cfs | → |
| Issaquah Creek Near Hobart | 27 cfs | → |
| Mercer Creek Near Bellevue | 12 cfs | → |
| Cedar River At Renton | 339 cfs | → |
| Snoqualmie River Near Snoqualmie | 1,610 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near South Ridge Stormwater Detention Dam.
Boat launches
- I 90 Trail Bellevue
- Mercer Island Boat Launch
- Northeast Tolt Hill Road 30348-30762, Carnation
- West Lake Sammamish Parkway Northeast Redmond
- Southeast Fish Hatchery Road 36495-37159, Fall City
- Shady Lake Boat Ramp
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
- Outlet Of Snoqualmie Lake To Alpine Lakes Wilderness Boundary
Track South Ridge 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 South Ridge Stormwater Detention Dam
Where does the data for South Ridge 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 South Ridge Stormwater Detention Dam.