Jonbar Ranch Dam dam
Jonbar Ranch Dam
Jonbar Ranch Dam, located in Dallas County, Iowa, was completed in 1957 and is owned and regulated by a private entity. The dam, designed by USDA NRCS, serves multiple purposes including fire protection and creating a stock or small fish pond. With a dam height of 25 feet and a storage capacity of 104 acre-feet, the structure is primarily made of earth and sits on a soil foundation along the TR-Johnson Creek.
Despite being classified as having a low hazard potential, the dam is subject to state regulation, inspection, and enforcement by the Iowa DNR. Its risk assessment is moderate, with no specific risk management measures listed. The dam's spillway is uncontrolled, and it has not been rated for its condition assessment. Overall, Jonbar Ranch Dam is a significant water resource structure in the area, providing essential functions for fire protection and local wildlife while being closely monitored for safety and regulatory compliance.
Water resource and climate enthusiasts may find Jonbar Ranch Dam an intriguing case study due to its unique design, multiple purposes, and the balance between its benefits and risks. The dam's location along the Raccoon River in Iowa, coupled with its low hazard potential and moderate risk assessment, offer insights into the complexities of managing water infrastructure in a changing climate. As a privately owned and state-regulated structure, Jonbar Ranch Dam exemplifies the interconnectedness between public and private entities in ensuring water security and safety in the region.
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 Jonbar Ranch Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Raccoon River At Van Meter | 1,710 cfs | → |
| Raccoon River Near West Des Moines | 1,320 cfs | → |
| Raccoon River At 63rd Street At Des Moines | 1,890 cfs | → |
| Walnut Creek At Des Moines | 44 cfs | → |
| Beaver Creek Near Grimes | 290 cfs | → |
| Raccoon River At Fleur Drive | 1,930 cfs | → |
About Jonbar Ranch Dam
Where does the data for Jonbar Ranch 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 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 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.