Thompson Valley Reservoir
Thompson Valley Reservoir is an earth dam located in Lake County, Oregon, built in 1922. It carries a Significant hazard potential classification.
About Thompson Valley Reservoir
The primary purpose of Thompson Valley Reservoir is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Silver Lake Irrigation District (local government). It impounds the Silver Creek near Silver Lake.
The dam stands 48 feet tall and stretches 290 feet across, creates a reservoir covering 1,900 acres, has a maximum storage capacity of 30,500 acre-feet, and collects water from a drainage area of 150 square miles. Completed in 1922, the structure is over a century old.
This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. The most recent inspection on record was 04/08/2020.
At 48 feet, this dam is taller than 92% of dams nationwide.
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Location
| State | Oregon |
| County | Lake |
| Nearest City | Silver Lake |
| River/Stream | Silver Creek |
| Coordinates | 42.96423, -121.08928 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 48 ft |
| Dam Height | 48 ft |
| Dam Length | 290 ft |
| Year Completed | 1922 (104 years old) |
Storage & Hydraulics
| NID Storage | 30,500 acre-ft |
| Max Storage | 30,500 acre-ft |
| Normal Storage | 21,040 acre-ft |
| Surface Area | 1,900 acres |
| Drainage Area | 150 sq mi |
| Max Discharge | 2,514 cfs |
Ownership & Safety
| Purpose | Irrigation |
| Owner | SILVER LAKE IRRIGATION DISTRICT |
| Owner Type | Local Government |
| Hazard Classification | Significant |
| Condition Assessment | Not Rated |
| Last Inspection | 04/08/2020 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | OR00145 |
| Federal ID | OR00145 |
| More Info | State Dam Safety Program |