Roche Harbor Lake Dam

Tr-Westcott Bay· San Juan, Washington· Built 2013· Earth·
High Hazard Water Supply Private

Key Takeaway

Roche Harbor Lake Dam is classified as high hazard in Washington. It was completed in 2013 and is 13 years old. Its primary use is water supply. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Length315 ft
Dam TypeEarth
Max Storage629 acre-ft
Normal Storage526 acre-ft
Surface Area28 acres
Drainage Area1 sq mi
Max Discharge272 cfs
Year Completed2013 (13 years old)
NID IDWA00444

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

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

Emergency Action Plan: Yes
Last Inspection: April 21, 2023
State Regulated: Yes
Regulatory Agency: Washington Dept of Ecology

Ownership

Roche Harbor Investments Inc c/o Saltch

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Roche Harbor Lake Dam?

Roche Harbor Lake Dam is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Roche Harbor Lake Dam?

Roche Harbor Lake Dam is owned by Roche Harbor Investments Inc c/o Saltch (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Roche Harbor Lake Dam built?

Roche Harbor Lake Dam was completed in 2013, making it 13 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 Roche Harbor Lake Dam?

Roche Harbor Lake Dam serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

When was Roche Harbor Lake Dam last inspected?

Roche Harbor Lake Dam was last inspected on April 21, 2023. 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.