Lake John

N FK NORTH PLATTE-TR· Jackson, Colorado· Built 1957· Earth· 25 ft tall
Significant Hazard Recreation Fish And Wildlife Pond State Government

Key Takeaway

Lake John is classified as significant hazard in Colorado. It was completed in 1957 and is 69 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 25 ft (taller than 53.1% in CO)
Dam Length1,723 ft
Dam TypeEarth
Max Storage16.1K acre-ft
Normal Storage7.1K acre-ft
Surface Area612 acres
Drainage Area2 sq mi
Max Discharge2,800 cfs
Year Completed1957 (69 years old)
NID IDCO00993

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: December 3, 2021
State Regulated: Yes
Regulatory Agency: DWR

Ownership

COLORADO PARKS AND WILDLIFE

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lake John?

Lake John 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 Lake John?

Lake John is owned by COLORADO PARKS AND WILDLIFE (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lake John built?

Lake John was completed in 1957, making it 69 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 Lake John?

Lake John serves the following purposes: Recreation, Fish And Wildlife Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Lake John?

Lake John has a dam height of 25 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 Lake John last inspected?

Lake John was last inspected on December 3, 2021. 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.