Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island)

TENNESSEE RIVER - OFFSTREAM· Humphreys, Tennessee· Built 1968· Earth· 41 ft tall
Significant Hazard Other Federal Government

Key Takeaway

Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) is classified as significant hazard in Tennessee. It was completed in 1968 and is 58 years old. Its primary use is other. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 41 ft (taller than 56% in TN)
Dam Length10,066 ft
Dam TypeEarth
Max Storage323 acre-ft
Normal Storage228 acre-ft
Surface Area101 acres
Drainage Area0 sq mi
Max Discharge279 cfs
Year Completed1968 (58 years old)
NID IDTN08512

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: April 30, 2021
State Regulated: No

Ownership

TVA

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island)?

Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) 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 Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island)?

Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) is owned by TVA (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) built?

Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) was completed in 1968, making it 58 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 Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island)?

Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) serves the following purposes: Other. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island)?

Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) has a dam height of 41 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 Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) last inspected?

Johnsonville Fossil Plant - Ash Disposal Area Perimeter Dike (Island) was last inspected on April 30, 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.