Johnson Dam (Washington Co)

Tr- Long Creek· Louisa, Iowa· Built 2005· Earth· 25 ft tall

Key Takeaway

Johnson Dam (Washington Co) is classified as low hazard in Iowa. It was completed in 2005 and is 21 years old. Its primary use is grade stabilization.

Physical Details

Dam Height 25 ft (taller than 19.3% in IA)
Dam Length500 ft
Dam TypeEarth
Max Storage159 acre-ft
Normal Storage0 acre-ft
Surface Area12 acres
Drainage Area0 sq mi
Max Discharge34 cfs
Year Completed2005 (21 years old)
NID IDIA04058

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
State Regulated: Yes
Regulatory Agency: IOWA DNR

Ownership

Jackie Johnson

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Johnson Dam (Washington Co)?

Johnson Dam (Washington Co) 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 Johnson Dam (Washington Co)?

Johnson Dam (Washington Co) is owned by Jackie Johnson (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Johnson Dam (Washington Co) built?

Johnson Dam (Washington Co) was completed in 2005, making it 21 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 Johnson Dam (Washington Co)?

Johnson Dam (Washington Co) serves the following purposes: Grade Stabilization, 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 Johnson Dam (Washington Co)?

Johnson Dam (Washington Co) 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.

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.