Gillham Dam
Gillham Dam is a concrete dam located in Howard County, Arkansas, built in 1975. It carries a High hazard potential classification.
About Gillham Dam
The primary purpose of Gillham 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 Usace - Little Rock District (federal). It impounds the Cossatot near Gillham.
The dam stands 160 feet tall and stretches 900 feet across, creates a reservoir covering 1,300 acres, has a maximum storage capacity of 221,800 acre-feet, and collects water from a drainage area of 271 square miles. Completed in 1975, the structure is well into its service life at over 50 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. An emergency action plan is in place for this dam. The most recent inspection on record was 12/07/2021.
At 160 feet, this dam is taller than 99% of all dams in the United States.
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 Arkansas 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 | Arkansas |
| County | Howard |
| Nearest City | Gillham |
| River/Stream | Cossatot |
| Coordinates | 34.21093, -94.22831 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 160 ft |
| Dam Height | 160 ft |
| Dam Length | 900 ft |
| Year Completed | 1975 (51 years old) |
Storage & Hydraulics
| NID Storage | 221,800 acre-ft |
| Max Storage | 221,800 acre-ft |
| Normal Storage | 33,100 acre-ft |
| Surface Area | 1,300 acres |
| Drainage Area | 271 sq mi |
| Max Discharge | 272,700 cfs |
| Spillway Type | None |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | USACE - Little Rock District |
| Owner Type | Federal |
| Hazard Classification | High |
| Condition Assessment | Not Available |
| Last Inspection | 12/07/2021 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | AR01200 |
| Federal ID | AR01200 |
| More Info | State Dam Safety Program |