Thompson Valley Reservoir

SILVER CREEK· Lake, Oregon· Built 1922· Earth· 48 ft tall
Significant Hazard Irrigation Local Government

Key Takeaway

Thompson Valley Reservoir is classified as significant hazard in Oregon. It was completed in 1922 and is 104 years old. Its primary use is irrigation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 48 ft (taller than 83.4% in OR)
Dam Length290 ft
Dam TypeEarth
Max Storage30.5K acre-ft
Normal Storage21.0K acre-ft
Surface Area1,900 acres
Drainage Area150 sq mi
Max Discharge2,514 cfs
Year Completed1922 (104 years old)
NID IDOR00145

Safety Information

Significant Hazard

No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: No
Last Inspection: April 8, 2020
State Regulated: Yes
Regulatory Agency: OWRD

Ownership

SILVER LAKE IRRIGATION DISTRICT

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Thompson Valley Reservoir?

Thompson Valley Reservoir is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Thompson Valley Reservoir?

Thompson Valley Reservoir is owned by SILVER LAKE IRRIGATION DISTRICT (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Thompson Valley Reservoir built?

Thompson Valley Reservoir was completed in 1922, making it 104 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of Thompson Valley Reservoir?

Thompson Valley Reservoir serves the following purposes: Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Thompson Valley Reservoir?

Thompson Valley Reservoir has a dam height of 48 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.

When was Thompson Valley Reservoir last inspected?

Thompson Valley Reservoir was last inspected on April 8, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.