This dataset is provided as part of the USGS National Hydrology Dataset and depicts the point locations for major dams in all fifty states and Puerto Rico. The dams locations in this dataset were pulled from the United States Army Corps or Engineers National Inventory of Dams (NID) database. Dams that are included in the NID must meet one of the following criteria: 1) High hazard classification - loss of one human life is likely if the dam fails, 2) Significant hazard classification - possible loss of human life and likely significant property or environmental destruction, 3) Equal or exceed 25 feet in height and exceed 15 acre-feet in storage, 4) Equal or exceed 50 acre-feet storage and exceed 6 feet in height. This dataset was retrieved from the USGS National Hydrology Dataset (NHD) website here: ftp://nhdftp.usgs.gov/DataSets/National/