Pierce

ROCK CREEK OFFSTREAM· Carbon, Wyoming· Built 1918· Earth· 30 ft tall
Significant Hazard Irrigation State Government

Key Takeaway

Pierce is classified as significant hazard in Wyoming. It was completed in 1918 and is 108 years old. Its primary use is irrigation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 30 ft (taller than 63.1% in WY)
Dam Length4,500 ft
Dam TypeEarth
Max Storage3.7K acre-ft
Normal Storage3.2K acre-ft
Surface Area199 acres
Drainage Area20 sq mi
Max Discharge1,323 cfs
Year Completed1918 (108 years old)
Year Modified1987
NID IDWY00357

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: Yes
Last Inspection: August 22, 2023
State Regulated: Yes
Regulatory Agency: SEO

Ownership

PIERCE RESERVOIR INCORPORATED

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Pierce?

Pierce 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 Pierce?

Pierce is owned by PIERCE RESERVOIR INCORPORATED (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Pierce built?

Pierce was completed in 1918, making it 108 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 Pierce?

Pierce 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 Pierce?

Pierce has a dam height of 30 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 Pierce last inspected?

Pierce was last inspected on August 22, 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.