Johnson (oscar) Dam is an earth dam located in Harrison County, Iowa, built in 2011. It carries a Low hazard potential classification.
Dam profile
NID height · 49 ft49 ft tall and 530 ft long, taller than 92% of U.S. dams with a recorded height. Height is drawn to scale against a ten-story building, about 100 ft; the profile is a generic embankment section and the water level is illustrative.
About Johnson (oscar) Dam
The primary purpose of Johnson (oscar) Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Oscar Johnson (private). It impounds the Trib to Elk Creek near Missouri Valley.
The dam stands 49 feet tall and stretches 530 feet across, creates a reservoir covering 6 acres, has a maximum storage capacity of 187 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 2011, the structure is relatively new.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life.
At 49 feet, this dam is taller than 92% of dams nationwide.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Iowa |
| County | Harrison |
| Nearest City | Missouri Valley |
| River/Stream | Trib to Elk Creek |
| Coordinates | 41.79110, -95.81890 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 49 ft |
| Dam Height | 49 ft |
| Dam Length | 530 ft |
| Year Completed | 2011 (15 years old) |
Storage & Hydraulics
| NID Storage | 187 acre-ft |
| Max Storage | 187 acre-ft |
| Normal Storage | 53 acre-ft |
| Surface Area | 6 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 150 cfs |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Oscar Johnson |
| Owner Type | Private |
| Hazard Classification | Low |
| Condition Assessment | Not assessed |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | IA04188 |
| Federal ID | IA04188 |
| More Info | State Dam Safety Program |