Dillon

Blue Creek· Summit, Colorado· Built 1963· Earth· 231 ft tall
High Hazard Water Supply Recreation Hydroelectric Local Government

Key Takeaway

Dillon is classified as high hazard in Colorado. It was completed in 1963 and is 63 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 Height 231 ft (taller than 99.1% in CO)
Dam Length4,625 ft
Dam TypeEarth
Max Storage305.0K acre-ft
Normal Storage254.0K acre-ft
Surface Area3,300 acres
Drainage Area338 sq mi
Max Discharge11,750 cfs
Year Completed1963 (63 years old)
NID IDCO02005

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: September 29, 2022
State Regulated: Yes
Regulatory Agency: DWR

Ownership

Denver Water

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Dillon?

Dillon 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 Dillon?

Dillon is owned by Denver Water (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Dillon built?

Dillon was completed in 1963, making it 63 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 Dillon?

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

How tall is Dillon?

Dillon has a dam height of 231 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 Dillon last inspected?

Dillon was last inspected on September 29, 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.