Tri Mountain Estates Dam
Tri Mountain Estates Dam is an earth dam located in Clark County, Washington, built in 1953. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Tri Mountain Estates Dam
The primary purpose of Tri Mountain Estates Dam is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Tri-mountain Estates Llc (private). It impounds the Tr-mason Creek near La Center.
The dam stands 32 feet tall and stretches 1,355 feet across, creates a reservoir covering 18 acres, has a maximum storage capacity of 177 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1953, 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. 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 08/25/2020.
At 32 feet, this dam is taller than 76% 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 Washington 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 | Washington |
| County | Clark |
| Nearest City | La Center |
| River/Stream | Tr-mason Creek |
| Coordinates | 45.87569, -122.58137 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 32 ft |
| Dam Length | 1,355 ft |
| Year Completed | 1953 (73 years old) |
Storage & Hydraulics
| NID Storage | 177 acre-ft |
| Max Storage | 177 acre-ft |
| Normal Storage | 137 acre-ft |
| Surface Area | 18 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 125 cfs |
Ownership & Safety
| Purpose | Irrigation |
| Owner | Tri-Mountain Estates LLC |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 08/25/2020 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | WA00103 |
| Federal ID | WA00103 |
| More Info | State Dam Safety Program |