Big Sand Wash West
Big Sand Wash West is an earth dam located in Duchesne County, Utah, built in 2006. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Big Sand Wash West
The primary purpose of Big Sand Wash West is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Moon Lake Water Users (private). It impounds the Big Sand Wash near Upalco.
The dam stands 55 feet tall and stretches 2,950 feet across, has a maximum storage capacity of 19,600 acre-feet, and collects water from a drainage area of 26 square miles. Completed in 2006, the structure is relatively new.
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 satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 05/10/2023.
At 55 feet, this dam is taller than 94% of dams nationwide.
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 | Duchesne |
| Nearest City | Upalco |
| River/Stream | Big Sand Wash |
| Coordinates | 40.29519, -110.23071 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 55 ft |
| Dam Length | 2,950 ft |
| Year Completed | 2006 (20 years old) |
Storage & Hydraulics
| NID Storage | 19,600 acre-ft |
| Max Storage | 19,600 acre-ft |
| Normal Storage | 18,800 acre-ft |
| Drainage Area | 26 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Irrigation |
| Owner | MOON LAKE WATER USERS |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/10/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | UT53328 |
| Federal ID | UT53326S002 |
| More Info | State Dam Safety Program |