Coolidge
Coolidge is a concrete dam located in Gila County, Arizona, built in 1931. It carries a High hazard potential classification and has a fair condition assessment.
About Coolidge
The primary purpose of Coolidge is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Bia (federal). It impounds the Gila River near Hayden.
The dam stands 250 feet tall and stretches 920 feet across, creates a reservoir covering 17,068 acres, has a maximum storage capacity of 1,356,337 acre-feet, and collects water from a drainage area of 15,302 square miles. Completed in 1931, the structure is well-established, with more than 75 years of service.
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 fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 02/24/2023.
At 250 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 Arizona 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 | Arizona |
| County | Gila |
| Nearest City | Hayden |
| River/Stream | Gila River |
| Coordinates | 33.17490, -110.52790 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 250 ft |
| Dam Height | 220 ft |
| Dam Length | 920 ft |
| Year Completed | 1931 (95 years old) |
Storage & Hydraulics
| NID Storage | 1,356,337 acre-ft |
| Max Storage | 1,356,337 acre-ft |
| Normal Storage | 872,976 acre-ft |
| Surface Area | 17,068 acres |
| Drainage Area | 15,302 sq mi |
| Max Discharge | 130,000 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Irrigation |
| Owner | BIA |
| Owner Type | Federal |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 02/24/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | AZ10436 |
| Federal ID | AZ10436 |
| More Info | State Dam Safety Program |