West Sunnyside Watershed Site A-1 dam
West Sunnyside Watershed Site A-1
West Sunnyside Watershed Site A-1 is a local government-owned earth dam located in Sioux City, Iowa, designed by USDA NRCS and completed in 1969. This dam serves multiple purposes including fire protection, stock, and small fish pond, as well as flood risk reduction. With a height of 38 feet and a length of 417 feet, the dam has a storage capacity of 70 acre-feet and covers a surface area of 3.8 acres, draining an area of 0.37 square miles.
Managed by the Iowa DNR, this watershed site on TR-Broken Kettle Creek has a low hazard potential and is classified as having a moderate risk level. The dam features an uncontrolled spillway and is inspected, permitted, and regulated by state authorities. Despite not being rated for condition assessment, the dam has not undergone any modifications since its completion and does not have an Emergency Action Plan (EAP) in place. With its critical role in water resource management and flood prevention, West Sunnyside Watershed Site A-1 is an essential infrastructure for the local community.
For water resource and climate enthusiasts, West Sunnyside Watershed Site A-1 offers a fascinating case study in dam engineering and management practices. As a key element in the regional water infrastructure, this earth dam exemplifies the balance between multiple water usage purposes and flood risk mitigation. With its location in Plymouth County, Iowa, and oversight by the Iowa DNR, the site presents an opportunity for further research and analysis on sustainable water resource management in the face of changing climate conditions.
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 West Sunnyside Watershed Site A-1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Perry Creek Near Milnerville | 25 cfs | → |
| Big Sioux River At Akron | 1,360 cfs | → |
| Floyd River At James | 613 cfs | → |
| Missouri River At Sioux City | 27,600 cfs | → |
| Vermillion River Nr Vermillion Sd | 146 cfs | → |
| Omaha Cr At Homer | 40 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near West Sunnyside Watershed Site A-1.
Boat launches
- 220th Street Plymouth County
- State Highway 3 Plymouth County
- 180th Street Plymouth County
- Ponca
- Scenic Park S Sioux City
- Bacon Creek Sioux City
Track West Sunnyside Watershed Site A-1 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 West Sunnyside Watershed Site A-1
Where does the data for West Sunnyside Watershed Site A-1 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 West Sunnyside Watershed Site A-1.