Kossler

WOODS GULCH· Boulder, Colorado· Built 1909· Earth· 20 ft tall

High Hazard Hydroelectric Local Government

Key Takeaway

Kossler is classified as high hazard in Colorado. It was completed in 1909 and is 117 years old. Its primary use is hydroelectric. 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 Height	20 ft (taller than 36.1% in CO)
Dam Length	450 ft
Dam Type	Earth
Max Storage	220 acre-ft
Normal Storage	180 acre-ft

Surface Area	13 acres
Drainage Area	0 sq mi
Max Discharge	300 cfs
Year Completed	1909 (117 years old)
NID ID	CO00231

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 13, 2022

State Regulated: Yes

Regulatory Agency: DWR

Ownership

CITY OF BOULDER (CLARK, KEVIN)

Local Government

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Frequently Asked Questions

What is the hazard classification of Kossler?

Kossler 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 Kossler?

Kossler is owned by CITY OF BOULDER (CLARK, KEVIN) (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Kossler built?

Kossler was completed in 1909, making it 117 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 Kossler?

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

How tall is Kossler?

Kossler has a dam height of 20 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 Kossler last inspected?

Kossler was last inspected on April 13, 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.