Lake Mary-phoebe
Lake Mary-phoebe is a gravity dam located in Salt Lake County, Utah, built in 1915. It carries a High hazard potential classification and has a poor condition assessment.
About Lake Mary-phoebe
The primary purpose of Lake Mary-phoebe is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Salt Lake City Corporation (private). It impounds the Trib. To Big Cottonwood Cr. near Brighton.
The dam stands 72 feet tall and stretches 330 feet across, has a storage capacity of 742 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1915, the structure is over a century 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 08/03/2023.
At 72 feet, this dam is taller than 96% 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 Utah 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 | Utah |
| County | Salt Lake |
| Nearest City | Brighton |
| River/Stream | Trib. To Big Cottonwood Cr. |
| Coordinates | 40.59185, -111.58742 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 72 ft |
| Dam Length | 330 ft |
| Year Completed | 1915 (111 years old) |
Storage & Hydraulics
| NID Storage | 742 acre-ft |
| Normal Storage | 742 acre-ft |
| Drainage Area | 1 sq mi |
| Max Discharge | 262 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | SALT LAKE CITY CORPORATION |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Poor |
| Last Inspection | 08/03/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | UT00172 |
| Federal ID | UT00172 |
| More Info | State Dam Safety Program |