Dam safety data

High-Hazard Dams Without an Emergency Action Plan

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

A high-hazard classification means failure would likely cause loss of life. An emergency action plan is the document that says who gets warned and how. 2,476 of the 17,049 high-hazard dams in the United States have no such plan on record — 14.5% of them. This is that gap, state by state, computed from the USACE National Inventory of Dams extract stamped 2026-8-28.

Download

high-hazard-without-eap.csv — all 52 states, with high-hazard counts, EAP status, condition ratings and totals. Free to reuse with attribution to USACE NID and PE-Calc.

Ranked by number of dams

North Carolina accounts for 25% of the entire national gap on its own — more than one in four — and has both the most high-hazard dams of any state and the largest number lacking a plan.

High-hazard dams with no EAP recorded — top 20 states, NID 2026-8-28
StateHigh-hazardNo EAPRateShare of US gap
North Carolina1,67863537.8%25%
Texas1,64832819.9%13%
Alabama22817878.1%7%
South Carolina67916824.7%6%
Indiana28212644.7%5%
West Virginia44811525.7%4%
New Mexico25511545.1%4%
Ohio4218119.2%3%
Maryland1076964.5%2%
Georgia5566010.8%2%
Florida1045451.9%2%
California877536.0%2%
Missouri1,478513.5%2%
Illinois2525019.8%2%
Rhode Island954648.4%1%
Mississippi3494011.5%1%
Virginia452378.2%1%
Pennsylvania788374.7%1%
Kansas3283510.7%1%
Washington416358.4%1%

Ranked by rate

Absolute counts favour big states. By proportion, among states with at least 50 high-hazard dams, the picture is different — and in several states most high-hazard dams have no plan at all.

Highest proportion without an EAP, states with ≥50 high-hazard dams
StateHigh-hazardNo EAPRate
Alabama22817878.1%
Maryland1076964.5%
Florida1045451.9%
Rhode Island954648.4%
New Mexico25511545.1%
Indiana28212644.7%
North Carolina1,67863537.8%
West Virginia44811525.7%
South Carolina67916824.7%
Texas1,64832819.9%
Illinois2525019.8%
Ohio4218119.2%

Who owns them

The gap is overwhelmingly private. 65% of high-hazard dams lacking a plan are privately owned — typically recreation and farm pond dams whose owners often do not know the structure is regulated, let alone that it carries a planning obligation. That is a very different policy problem from a public agency failing to file.

Ownership of high-hazard dams with no EAP recorded
Owner typeDamsShare
Private1,62965%
Local Government55022%
Not Listed1154%
State853%
Federal491%
Public Utility401%

Condition of high-hazard dams

Separately from planning, 2,791 high-hazard dams are rated Poor or Unsatisfactory. These ratings are dam-safety findings, not maintenance notes: they mean identified deficiencies that could lead to failure under loading the dam is expected to withstand.

High-hazard dams rated Poor or Unsatisfactory — top 12 states
StateHigh-hazardPoorUnsat.Rate
North Carolina1,6782083914.7%
Texas1,64810511213.2%
Georgia556189434.7%
South Carolina6791451723.9%
New Mexico255136956.9%
Pennsylvania7881341118.4%
Mississippi349815940.1%
Ohio421128431.4%
New York451111525.7%
Kentucky277891738.3%
Indiana28289232.3%
Hawaii118751374.6%

Method, and what these numbers do not say

Basis. High-hazard-potential dams only. State EAP requirements differ — North Carolina requires plans for high and intermediate hazard dams under G.S. 143-215.31(a1), while other states set the bar elsewhere — so a fifty-state ranking that mixed those bases would be comparing different legal obligations. High hazard is the one cohort where essentially every state requires a plan, which makes it the only honest basis for a national comparison. It also means these figures understate the true gap in states like North Carolina.

Limits. NID reflects what state and federal programs have reported to USACE. It can lag a state program's own records, and "EAP Prepared: No" means no plan is recorded in the inventory rather than proof that no plan exists. A dam newly classified may legitimately be inside its filing window. Treat these as inventory figures, not as compliance findings about any individual structure.

Reproducing it. Pull the national extract from https://nid.sec.usace.army.mil/api/nation/csv and group by State, Hazard Potential Classification and EAP Prepared. The build script that generates this page is open source.

The requirements behind the numbers

NC EAP Requirements →
G.S. 143-215.31(a1): who must file, and when
Hazard Classification
What makes a dam high hazard in the first place
Breach Analysis Worked
The modelling behind an inundation map

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