Question
How many dams are in poor condition?
As of October 30, 2026, 9,023 of the 92,692 records are rated Poor or Unsatisfactory, 21,455 have no published condition and 36,627 are Not Rated, according to the National Inventory of Dams.
Poor and Unsatisfactory are two of the NID’s ratings, and its definition of Not Rated is “The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.” Poor or Unsatisfactory is 12.7% of the 71,237 records whose condition the NID publishes, a count that includes the Not Rated ones.
Data retrieved
The figures behind this
| Condition assessment | Records | High-hazard records |
|---|---|---|
| Satisfactory | 12,906 | 5,301 |
| Fair | 12,681 | 5,158 |
| Poor | 7,889 | 2,289 |
| Unsatisfactory | 1,134 | 505 |
| Not Rated | 36,627 | 2,151 |
| Not published: the condition assessment is not provided to the NID | 3,532 | 1,398 |
| Not published: no condition assessment in the NID | 17,923 | 234 |
| All records | 92,692 | 17,036 |
Where to go next
More questions about Dams
- How old are dams in the US?
18,610 records, 1960-1969 October 2026
- Who owns the dams in the US?
60,388 records, Private October 2026
- What are dams used for?
30,935 records, Recreation October 2026
- How many high-hazard dams have EAPs?
13,191 records October 2026
Sources
- National Inventory of Dams — national CSV — U.S. Army Corps of Engineers, National Inventory of Dams · U.S. Government work · retrieved November 5, 2026
Compiled automatically from National Inventory of Dams — national CSV by a checked SQL query · Editor: Kian O'Connor · How this site is built
How to cite this page
Cite the page’s address and the date printed on it, and name U.S. Army Corps of Engineers, National Inventory of Dams as the source of the figures.
American Factbook. “How many dams are in poor condition?.” Updated November 5, 2026. https://americanfactbook.org/dams/dams-in-poor-condition. Source: National Inventory of Dams — national CSV, https://nid.sec.usace.army.mil/.