Iatt Lake Dam

Bayou Rigolette· Grant, Louisiana· Built 1956· Earth· 36 ft tall
High Hazard Recreation State Government

Key Takeaway

Iatt Lake Dam is classified as high hazard in Louisiana. It was completed in 1956 and is 70 years old. Its primary use is recreation. 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 36 ft (taller than 93.5% in LA)
Dam Length5,310 ft
Dam TypeEarth
Max Storage167.0K acre-ft
Normal Storage31.0K acre-ft
Surface Area7,100 acres
Drainage Area242 sq mi
Max Discharge12,128 cfs
Year Completed1956 (70 years old)
Year Modified1966
NID IDLA00018

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: August 30, 2023
State Regulated: Yes
Regulatory Agency: LA DOTD

Ownership

State of Louisiana

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Iatt Lake Dam?

Iatt Lake Dam 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 Iatt Lake Dam?

Iatt Lake Dam is owned by State of Louisiana (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Iatt Lake Dam built?

Iatt Lake Dam was completed in 1956, making it 70 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 Iatt Lake Dam?

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

How tall is Iatt Lake Dam?

Iatt Lake Dam has a dam height of 36 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 Iatt Lake Dam last inspected?

Iatt Lake Dam was last inspected on August 30, 2023. 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.