Cow Lake Dam

Cow Creek· Adams, Washington· Built 1935· Gravity·
Low Hazard Irrigation Recreation Private

Key Takeaway

Cow Lake Dam is classified as low hazard in Washington. It was completed in 1935 and is 91 years old. Its primary use is irrigation.

Physical Details

Dam Length600 ft
Dam TypeGravity
Max Storage900 acre-ft
Normal Storage500 acre-ft
Surface Area240 acres
Drainage Area315 sq mi
Max Discharge95 cfs
Year Completed1935 (91 years old)
NID IDWA01267

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

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

Emergency Action Plan: No
State Regulated: Yes
Regulatory Agency: Washington Dept of Ecology

Ownership

JohnHarder

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Cow Lake Dam?

Cow Lake Dam is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Cow Lake Dam?

Cow Lake Dam is owned by JohnHarder (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Cow Lake Dam built?

Cow Lake Dam was completed in 1935, making it 91 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 Cow Lake Dam?

Cow Lake Dam serves the following purposes: Irrigation, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

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.