A key set of tools for reporters probing dam issues at any level, local to national, are the available databases on various kinds of dams, levees, and impoundments. The WatchDog in this issue presents a special "Reporters' Toolbox" on these data sets. We hope at least to help reporters find and access them.
The most important of these is the National Inventory of Dams  (NID) , which contains information on the roughly 84,000 most important dams in the United States. The Army Corps of Engineers, which collects and maintains it, has made it somewhat hard to use, and has blacked out dam hazard ratings and inspection results. This makes it harder for journalists to inform the public and for the public to protect themselves. Still, the NID is a good starting point for a variety of good stories.
This toolbox includes discussion of (and links to) many other dam-related databases. They include the National Performance of Dams Program , the Federal Energy Regulatory Commission's hydropower licensing data , the National Levee Database , the Coal Impoundment Location and Information System,  EPA's Coal Combustion Residuals Impoundment Database , a Nuclear Regulatory Commission list of nuclear plants at risk  from dam failure and flooding events, sources of dam removal data , some pointers to state dam databases , an assessment of undocumented and unpermitted dams , and other relevant data sources .
To read the complete article on "Data Resources for Dams, Impoundments, and Levees," click here. 
This article is part of the October 23, 2013 special issue of the WatchDog  on the transparency of safety information related to dams, levees, impoundments, and related water-control structures.