The Transportation Department has a backlog between $80 billion and $100 billion in high-priority infrastructure improvement projects that it cannot afford to fund, Secretary Ray LaHood said Wednesday.

"For a decade, we've really ignored infrastructure," LaHood told the Senate Budget Committee. "We just haven't put the resources into it. There's a lot of lousy bridges and roads that need to be constructed."

LaHood said the Transportation Investment Generating Economic Recovery, or Tiger, grant program received applications for projects totaling $60 billion. But the Tiger program only had $1.5 billion to award as part of last year's American Recovery and Reinvestment Act.

Committee Chairman Kent Conrad, D-N.D., said he wished Congress had passed a larger stimulus bill to fund more bridge, road and rail construction.

"These projects have real merit," Conrad said.

The White House has proposed a Transportation budget of nearly $78 billion for fiscal 2011, which would represent a $1.5 billion increase over this year. LaHood said the budget would help pay for high-speed rail, highway and transit safety programs, and air traffic control modernization.

The Next Generation Air Transportation System, also called NextGen, would receive $1.1 billion next year, $275 million more than it received in fiscal 2010. The program aims to modernize the nation's air traffic control system by moving from ground-based radar to a more accurate satellite-based surveillance system.

"While we are talking about the future of aviation, I'm pleased to report that it's happening now," LaHood said. "The system is already being used in the Gulf of Mexico, which is improving the safety and accuracy of air traffic services in the Gulf."