Grafton

MILWAUKEE· Ozaukee, Wisconsin· Built 1918· Buttress· 20 ft tall
Significant Hazard Recreation Local Government

Key Takeaway

Grafton is classified as significant hazard in Wisconsin. It was completed in 1918 and is 108 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 20 ft (taller than 60.1% in WI)
Dam Length206 ft
Dam TypeButtress
Max Storage400 acre-ft
Normal Storage260 acre-ft
Surface Area35 acres
Drainage Area451 sq mi
Max Discharge15,420 cfs
Year Completed1918 (108 years old)
NID IDWI00171

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: June 16, 2021
State Regulated: Yes
Regulatory Agency: WIDNR

Ownership

Village Of Grafton

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Grafton?

Grafton 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 Grafton?

Grafton is owned by Village Of Grafton (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Grafton built?

Grafton was completed in 1918, making it 108 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 Grafton?

Grafton 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 Grafton?

Grafton has a dam height of 20 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 Grafton last inspected?

Grafton was last inspected on June 16, 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.