Significant Hazard Dams
No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.
| Dam Name | Hazard | Height | Built | Type | State |
|---|---|---|---|---|---|
| Waterville Pond Dam Plymouth | Significant Hazard | 16 ft | 1920 | Earth | Massachusetts |
| Waterville Reservoir Dam #2 Oneida | Significant Hazard | 10 ft | 1917 | Masonry | New York |
| Waterville Upper Storage Reservoir Dam Oneida | Significant Hazard | 41 ft | 1953 | Earth | New York |
| Waterville Valley Lagoons Dam Grafton | Significant Hazard | 19 ft | 1972 | Earth | New Hampshire |
| Watervliet Balancing Reservoir Dam Albany | Significant Hazard | 20 ft | 1915 | Earth | New York |
| Watkins Lake Dam Wake | Significant Hazard | — | 1950 | Earth | North Carolina |
| Watkins Lake Dam Fayette | Significant Hazard | 18 ft | 1950 | Earth | Alabama |
| Watopa Township No. 1 Wabasha | Significant Hazard | 32 ft | 1976 | Earth | Minnesota |
| Watson Dam Webster | Significant Hazard | 17 ft | 1995 | Earth | Nebraska |
| Watson Pond Bristol | Significant Hazard | 9 ft | — | Earth | Massachusetts |
| Watson Road Dam Berkshire | Significant Hazard | 9 ft | 1965 | Earth | Massachusetts |
| Watson'S Lake Dam Camden | Significant Hazard | 15 ft | — | Earth | New Jersey |
| Watters #1 Powder River | Significant Hazard | 29 ft | 1966 | Earth | Montana |
| Watts A.K.A. Hamilton Pond Dam Hartford | Significant Hazard | 11 ft | — | Earth | Connecticut |
| Watts Bros Organic Dairy Lagoon 1 Benton | Significant Hazard | — | 2007 | Earth | Washington |
| Watts Bros Organic Dairy Lagoon 2 Benton | Significant Hazard | — | 2007 | Earth | Washington |
| Watts Bros Organic Dairy Lagoon 3 Benton | Significant Hazard | — | 2007 | Earth | Washington |
| Waubeeka Lake Dam Fairfield | Significant Hazard | 10 ft | 1933 | Earth | Connecticut |
| Wauconda Douglas | Significant Hazard | 42 ft | 1974 | Earth | Colorado |
| Waukegan Station East Ash Pond Dam Lake | Significant Hazard | 20 ft | 1979 | Earth | Illinois |
| Waukegan Station West Ash Pond Lake | Significant Hazard | 20 ft | 1979 | Earth | Illinois |
| Wau-Me-Gah Lake Dam Oakland | Significant Hazard | 8 ft | 1930 | Earth | Michigan |
| Wauneta North Dam Chase | Significant Hazard | 72 ft | 1970 | Earth | Nebraska |
| Waupee Dam Oconto | Significant Hazard | 11 ft | 1944 | Earth | Wisconsin |
| Wauseon Upground Reservoir No. 1 Fulton | Significant Hazard | 29 ft | 1921 | Earth | Ohio |
| Waverly Avenue Somerset | Significant Hazard | 11 ft | 1893 | Concrete | Maine |
| Waverly Park Dam Jefferson | Significant Hazard | 22 ft | 1969 | Earth | Kentucky |
| W A Williamson Elmore | Significant Hazard | — | 1955 | Earth | Alabama |
| Waycross Episcopal Camp Lake Dam Brown | Significant Hazard | 44 ft | 1963 | Earth | Indiana |
| Wayne Carter Lake Dam Poinsett | Significant Hazard | — | 1969 | Earth | Arkansas |
| Wayne Wwt Lagoon Wood | Significant Hazard | 9 ft | 1996 | Earth | Ohio |
| Waynoka Wwt Lagoon Brown | Significant Hazard | 13 ft | 1995 | Earth | Ohio |
| Wayside Pond Dam Worcester | Significant Hazard | 8 ft | 1964 | Earth | Massachusetts |
| Wc 3(A) Mix Area Manatee | Significant Hazard | 12 ft | 1992 | Earth | Florida |
| W D Harrigan Dam Clarke | Significant Hazard | — | 1960 | Earth | Alabama |
| W.D. Mayo Lock and Dam Sequoyah | Significant Hazard | 71 ft | 1970 | Gravity | Oklahoma |
| W-Drain Gooding | Significant Hazard | 17 ft | 2008 | — | Idaho |
| Weasel Brook Park Dam Passaic | Significant Hazard | 6 ft | — | Concrete | New Jersey |
| Weatherfordbear #1b Wayne | Significant Hazard | — | 1970 | Earth | Tennessee |
| Weatherhead Hollow Pond Windham | Significant Hazard | 17 ft | 1965 | Earth | Vermont |
| Webbers Falls Lock and Dam Muskogee | Significant Hazard | 84 ft | 1970 | Gravity | Oklahoma |
| Weber/Box Elder - B Reservoir Weber | Significant Hazard | — | — | Earth | Utah |
| Weber/Box Elder - D Reservoir - 900 West Weber | Significant Hazard | — | 1991 | Earth | Utah |
| Weber/Box Elder - F Reservoir Weber | Significant Hazard | — | — | Earth | Utah |
| Weber/Box Elder - H Reservoir (Lower) Weber | Significant Hazard | — | — | Earth | Utah |
| Weber/Box Elder - J Reservoir Weber | Significant Hazard | — | — | Earth | Utah |
| Weber/Box Elder - L Reservoir Weber | Significant Hazard | — | — | Earth | Utah |
| Weber/Box Elder - Reservoir 3 - Unit C Weber | Significant Hazard | — | — | Earth | Utah |
| Weber/Box Elder - Westview Reservoir Weber | Significant Hazard | — | — | Earth | Utah |
| Webster Merrimack | Significant Hazard | 22 ft | 1917 | Concrete | New Hampshire |