Lock and Dam No 8

OUACHITA RIVER· Union, Arkansas· Built 1911· Gravity· 25 ft tall
Low Hazard Navigation Federal Government

Key Takeaway

Lock and Dam No 8 is classified as low hazard in Arkansas. It was completed in 1911 and is 115 years old. Its primary use is navigation.

Physical Details

Dam Height 25 ft (taller than 44.1% in AR)
Dam Length334 ft
Dam TypeGravity
Max Storage85.0K acre-ft
Normal Storage59.2K acre-ft
Max Discharge6,500 cfs
Year Completed1911 (115 years old)
NID IDAR00156

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: January 1, 1990
State Regulated: No

Ownership

DAEN LMK

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lock and Dam No 8?

Lock and Dam No 8 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 Lock and Dam No 8?

Lock and Dam No 8 is owned by DAEN LMK (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lock and Dam No 8 built?

Lock and Dam No 8 was completed in 1911, making it 115 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 Lock and Dam No 8?

Lock and Dam No 8 serves the following purposes: Navigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Lock and Dam No 8?

Lock and Dam No 8 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 Lock and Dam No 8 last inspected?

Lock and Dam No 8 was last inspected on January 1, 1990. 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.