Williams Valley

Tr Short Creek· Mendocino, California· Built 1965· Earth· 47 ft tall
Low Hazard Water Supply Tailings Irrigation Private

Key Takeaway

Williams Valley is classified as low hazard in California. It was completed in 1965 and is 61 years old. Its primary use is water supply.

Physical Details

Dam Height 47 ft (taller than 56.2% in CA)
Dam Length243 ft
Dam TypeEarth
Max Storage200 acre-ft
Surface Area15 acres
Drainage Area1 sq mi
Year Completed1965 (61 years old)
NID IDCA00973

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
Last Inspection: March 28, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Private Entity

Private

Frequently Asked Questions

What is the hazard classification of Williams Valley?

Williams Valley 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 Williams Valley?

Williams Valley is owned by Private Entity (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Williams Valley built?

Williams Valley was completed in 1965, making it 61 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 Williams Valley?

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

How tall is Williams Valley?

Williams Valley has a dam height of 47 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 Williams Valley last inspected?

Williams Valley was last inspected on March 28, 2022. 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.