Dam safety by state

Dams in Wisconsin

By Michael Flynn, PE · water resources & dam safety engineer

Wisconsin has 996 dams in the National Inventory of Dams, of which 198 are classified high hazard — and only 4.5% lack an emergency action plan, one of the better records nationally. Inventory, condition and hazard data computed from the USACE extract stamped 2026-8-28, with the governing law cited below.

What this page is

Verified inventory data and a pointer to where Wisconsin's dam safety law lives. It deliberately does not summarise what that law requires — those requirements have not been checked against current primary sources for Wisconsin, and a stale paraphrase of a dam safety statute is worse than none.

For a state written up in full, see North Carolina.

Wisconsin by the numbers

Wisconsin dam inventory — NID extract 2026-8-28
MeasureCountNational rank
Total dams99631st
High hazard19828th
— with an EAP recorded189
— with no EAP recorded926th largest gap
— EAP not required0
High hazard rated Poor2
High hazard rated Unsatisfactory4

6 of Wisconsin's high-hazard dams are rated Poor or Unsatisfactory (3.0% of them).

Governing law

The Wisconsin dam safety law is contained in the Wisconsin Statutes Chapter 31 ยง Regulation of Dams and Bridges Affecting Navigable Waters, originally enacted in 1917 under the Water Power Law (Wis. Stat.

Citation compiled from the ASDSO 2020 summary of state dam safety laws and checked to refer to Wisconsin. It tells you where the law lives, not what it currently says: statutes get amended and section numbers get renumbered. Read the current text before relying on it, and contact the Wisconsin dam safety program for a determination that binds.

Counties with the most dams

Wisconsin dams by county — NID extract 2026-8-28
CountyDamsHigh hazardPoor/Unsat.
Juneau4527
Taylor3833
Price3731
Marinette27110
Oneida26101
Vernon2692
Chippewa2580
Jackson2432
Waukesha2450
Sauk2421
Sawyer2340
Burnett2311

Where to go for Wisconsin's requirements

This page does not summarise what Wisconsin law requires. These do, or will point you at someone who can:

How Wisconsin compares

Nationally, 2,476 of 17,049 high-hazard dams have no emergency action plan on record. Wisconsin accounts for 0.4% of that gap. Full rankings, method and the downloadable dataset are on the national EAP gap page.

National EAP Gap Data →
All states ranked, with CSV
A State Written Up in Full
North Carolina: classification, permits, EAPs
Dam Safety Calculators
Breach, spillway, seepage, stability

Data source. Computed from the U.S. Army Corps of Engineers National Inventory of Dams national extract, stamped 2026-8-28. NID reflects what state and federal programs have reported to USACE; an "EAP Prepared: No" flag means no plan is recorded rather than proof that none exists.

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