Held Watershed Site E-3
Held Watershed Site E-3 is an earth dam located in Plymouth County, Iowa, built in 1978. It carries a High hazard potential classification and has a poor condition assessment.
About Held Watershed Site E-3
The primary purpose of Held Watershed Site E-3 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 Plymouth County Swcd (local government). It impounds the Tr-floyd River near Hinton.
The dam stands 43 feet tall and stretches 530 feet across, creates a reservoir covering 4 acres, has a maximum storage capacity of 118 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1978, the structure is 48 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. An emergency action plan is in place for this dam. The most recent inspection on record was 10/10/2024.
At 43 feet, this dam is taller than 89% of dams nationwide.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Iowa dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Iowa |
| County | Plymouth |
| Nearest City | Hinton |
| River/Stream | Tr-floyd River |
| Coordinates | 42.63990, -96.30690 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 43 ft |
| Dam Height | 43 ft |
| Dam Length | 530 ft |
| Year Completed | 1978 (48 years old) |
Storage & Hydraulics
| NID Storage | 118 acre-ft |
| Max Storage | 118 acre-ft |
| Normal Storage | 47 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 0 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Plymouth County SWCD |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Poor |
| Last Inspection | 10/10/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | IA01857 |
| Federal ID | IA01857 |
| More Info | State Dam Safety Program |