Otranto Dam dam
Otranto Dam
Located in St. Ansgar, Iowa, the Otranto Dam is a gravity-type structure built in 1902 for recreational purposes along the Cedar River. With a height of 7 feet and a length of 170 feet, the dam provides a storage capacity of 168 acre-feet and covers a surface area of 48 acres. Despite its low hazard potential, the dam is regulated by the Iowa Department of Natural Resources and undergoes regular inspections, permitting, and enforcement to ensure its safety and compliance with state regulations.
The Otranto Dam is situated in Mitchell County, Iowa, under the jurisdiction of the Rock Island District of the US Army Corps of Engineers. While it has not been modified in recent years and its condition remains unrated, the dam poses a moderate risk, prompting the need for ongoing risk assessment and management measures. The dam features an uncontrolled spillway and is surrounded by a drainage area of 656 square miles. As a key recreational attraction in the area, the dam serves as a vital water resource for the community while offering opportunities for outdoor activities and enjoyment.
Despite its age, the Otranto Dam continues to be a significant landmark in the region, providing both recreational benefits and essential water storage capacity. With its historical significance and environmental impact on the Cedar River, the dam underscores the importance of sustainable water resource management and climate resilience efforts in the face of changing weather patterns and increasing risks associated with dam safety.
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 Otranto Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Cedar River Near Austin | 158 cfs | → |
| Winnebago River At Mason City | 338 cfs | → |
| Cedar River At Charles City | 531 cfs | → |
| Little Cedar River Near Ionia | 232 cfs | → |
| South Fork Zumbro River At Rochester | 109 cfs | → |
| Root River Near Pilot Mound | 349 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Otranto Dam.
Boat launches
- Oakland Place Northeast Austin
- Finch Avenue Worth County
- Wapsi Great Western Line Mitchell County
- Worth County
- West Richway Drive 630, Albert Lea
- Big Blue Loop Mason City
Campgrounds
- Otranto County Park Campground
- Halvorson County Park Campground
- Riverside County Park Campground
- Interstate County Park Campground
- Osage Sprink Park Campground
- Camping
Track Otranto 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 Otranto Dam
Where does the data for Otranto 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 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 Otranto Dam.