In the middle of the night on Nov. 6, 1977, the Kelly Barnes Dam near Toccoa Falls, Georgia, gave way, unleashing a wall of water that killed 39 people. In a report, federal investigators blamed the failure on a combination of factors, including heavy rains and a breach in the 38-year-old earthen dam’s crest that had been followed by progressive erosion.

The disaster prompted President Jimmy Carter to direct the U.S. Army Corps of Engineers to begin inspecting the nation’s “non-federal high-hazard dams,” according to the Association of State Dam Safety Officials. The findings of this inspection program were responsible for the establishment of dam safety programs in most states.

The Corps maintains inspection data on some 79,000 dams around the country. Its National Inventory of Dams is open to the public, but with restrictions. Upon recommendation of the security-conscious National Dam Safety Review Board in 2007, the Corps blocked public access to key fields such as the downstream hazard potential and the city nearest the dam.

Moreover, the public can no longer download the entire database, a tool long favored by journalists interested in assessing dam safety in their communities. A professional association, Investigative Reporters and Editors, makes data from 1993 through 2002 available to news organizations for a modest fee. Because of the Corps-imposed restrictions, however, there’s no way for the public to know which downstream areas were classified as high-hazard in, say, 2008 or 2009. This is information residents of Toccoa Falls no doubt would have appreciated having available to them 32 years ago.

ABOUT THE DATA:

What: National Inventory of Dams
Where: U.S. Army Corps of Engineers, Washington, D.C.
Availability: Open to the public with restrictions

Usability: Public can no longer download entire database; all government and non-government users must have ID and password to query the database and use the interactive map

Email your tips on government data sets that you think should be made more accessible or user-friendly. We’re eager to hear what you turn up — full credit and links will be provided to individuals whose suggestions we use in our series.

The Data Mine is a joint project of the Center for Public Integrity and the Sunlight Foundation.