Willow Lake dam
Willow Lake
Willow Lake, located in Johnson County, Kansas, is a privately owned structure designed by the USDA NRCS, with a primary purpose of serving as a fire protection, stock, or small fish pond. Completed in 1960, this earth dam stands at a height of 28 feet and spans a length of 850 feet, with a storage capacity of 136.5 acre-feet. The dam is regulated by the Kansas Department of Agriculture and undergoes regular inspections to ensure its safety and functionality.
With a high hazard potential and an unsatisfactory condition assessment, Willow Lake poses a moderate risk that necessitates careful monitoring and management. The spillway, with a width of 94 feet, is uncontrolled, and the dam lacks outlet gates for water release. Despite these challenges, the dam continues to provide essential services for debris control, fire protection, and water storage in the area. The surrounding Blue River-TR watershed benefits from the lake's presence, supporting the local ecosystem and water resources in the region.
As climate change impacts water resources and infrastructure, the resilience and maintenance of structures like Willow Lake become increasingly vital. With its historical significance and ongoing role in serving the community, Willow Lake stands as a testament to the importance of sustainable water management practices. Through continued monitoring, risk assessment, and potential upgrades, Willow Lake can adapt to changing conditions and continue to fulfill its critical functions for the environment and stakeholders in the region.
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 Willow Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Blue R At Kenneth Rd | 19 cfs | → |
| Blue River At Blue Ridge Blvd Ext In Kc | 29 cfs | → |
| Tomahawk C Nr Overland Park | 4 cfs | → |
| Indian C At State Line Rd | 44 cfs | → |
| Blue R Nr Stanley | 9 cfs | → |
| Indian C At Overland Park | 16 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Willow Lake.
Boat launches
- River Trail Kansas City
- East Loch Lloyd Parkway Loch Lloyd
- Southeast Raytown Road Lee's Summit
- Monticello Road Lenexa
- Olathe Lake Boat Ramp
- West 103rd Street Olathe
Track Willow Lake 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 Willow Lake
Where does the data for Willow Lake 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 Willow Lake.