Henry is an earth dam located in Bon Homme County, South Dakota, built in 1938. It carries a Significant hazard potential classification.
Dam profile
NID height · 45 ft45 ft tall and 1,050 ft long, taller than 90% of U.S. dams with a recorded height. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
About Henry
The primary purpose of Henry is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Gf&p (state). It impounds the Dawson Creek.
The dam stands 45 feet tall and stretches 1,050 feet across, creates a reservoir covering 125 acres, has a maximum storage capacity of 3,000 acre-feet, and collects water from a drainage area of 40 square miles. Completed in 1938, the structure is well-established, with more than 75 years of service.
This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. The most recent inspection on record was 10/03/2022.
At 45 feet, this dam is taller than 90% of dams nationwide.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | South Dakota |
| County | Bon Homme |
| River/Stream | Dawson Creek |
| Coordinates | 43.14445, -97.69400 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 45 ft |
| Dam Height | 45 ft |
| Dam Length | 1,050 ft |
| Year Completed | 1938 (88 years old) |
Storage & Hydraulics
| NID Storage | 3,000 acre-ft |
| Max Storage | 3,000 acre-ft |
| Normal Storage | 1,769 acre-ft |
| Surface Area | 125 acres |
| Drainage Area | 40 sq mi |
| Max Discharge | 11,000 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | Gf&p |
| Owner Type | State |
| Hazard Classification | Significant |
| Condition Assessment | Not assessed |
| Last Inspection | 10/03/2022 |
Identifiers
| NID ID | SD00004 |
| Federal ID | SD00004 |
| More Info | State Dam Safety Program |