Stewart Mountain Dam
Stewart Mountain Dam is a concrete dam located in Maricopa County, Arizona, built in 1930. It carries a High hazard potential classification.
About Stewart Mountain Dam
The primary purpose of Stewart Mountain Dam is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Bureau Of Reclamation (federal). It impounds the Salt River near Mesa.
The dam stands 210 feet tall and stretches 1,260 feet across, creates a reservoir covering 1,265 acres, has a maximum storage capacity of 70,070 acre-feet, and collects water from a drainage area of 6,191 square miles. Completed in 1930, 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. An emergency action plan is in place for this dam. The most recent inspection on record was 05/25/2021.
At 210 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 | Maricopa |
| Nearest City | Mesa |
| River/Stream | Salt River |
| Coordinates | 33.56650, -111.53590 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 210 ft |
| Dam Height | 207 ft |
| Dam Length | 1,260 ft |
| Year Completed | 1930 (96 years old) |
Storage & Hydraulics
| NID Storage | 70,070 acre-ft |
| Max Storage | 70,070 acre-ft |
| Normal Storage | 69,765 acre-ft |
| Surface Area | 1,265 acres |
| Drainage Area | 6,191 sq mi |
| Max Discharge | 105,000 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | BUREAU OF RECLAMATION |
| Owner Type | Federal |
| Hazard Classification | High |
| Condition Assessment | Not Available |
| Last Inspection | 05/25/2021 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | AZ10318 |
| Federal ID | AZ10318 |
| More Info | State Dam Safety Program |