"TIGER first appeared as part of the stimulus package, when $1.5 billion in competitive grants was allocated to state and local governments for transportation projects. A second round, called TIGER II, was included in the 2010 budget and provided $600 billion. The latest round of funding is part of the 2011 budget the president signed in April after lengthy negotiations with congressional Republicans."
Of the $527 million available in the third round of TIGER, at least $140 million will be designated for rural projects, according to Ryan Holywell of Governing.
The purpose of the grants is to fund projects which improve the condition of existing facilities, contribute to the country's economic competitiveness, foster livable communities, improve energy efficiency, and improve safety.