D.O.E. Rocky Flats A-4

NORTH WALNUT CREEK· Jefferson, Colorado· Built 1979· Earth· 40 ft tall
Low Hazard Flood Risk Reduction Other Federal Government

Key Takeaway

D.O.E. Rocky Flats A-4 is classified as low hazard in Colorado. It was completed in 1979 and is 47 years old. Its primary use is flood risk reduction.

Physical Details

Dam Height 40 ft (taller than 81.3% in CO)
Dam Length1,050 ft
Dam TypeEarth
Max Storage160 acre-ft
Normal Storage99 acre-ft
Surface Area9 acres
Drainage Area2 sq mi
Max Discharge6,000 cfs
Year Completed1979 (47 years old)
Year Modified1996
NID IDCO02243

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: October 20, 2011
State Regulated: Yes
Regulatory Agency: DWR

Ownership

DOE LEGACY MANAGEMENT

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of D.O.E. Rocky Flats A-4?

D.O.E. Rocky Flats A-4 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 D.O.E. Rocky Flats A-4?

D.O.E. Rocky Flats A-4 is owned by DOE LEGACY MANAGEMENT (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was D.O.E. Rocky Flats A-4 built?

D.O.E. Rocky Flats A-4 was completed in 1979, making it 47 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 D.O.E. Rocky Flats A-4?

D.O.E. Rocky Flats A-4 serves the following purposes: Flood Risk Reduction, Other. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is D.O.E. Rocky Flats A-4?

D.O.E. Rocky Flats A-4 has a dam height of 40 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 D.O.E. Rocky Flats A-4 last inspected?

D.O.E. Rocky Flats A-4 was last inspected on October 20, 2011. 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.