The East Room signing ceremony before an audience of lawmakers, construction workers and college students came on Obama's return to the White House following a two-day campaign swing by bus through Ohio and Pennsylvania.
"This bill will keep thousands of construction workers on the job rebuilding our nation's infrastructure," Obama said. "Second, this bill will keep interest rates on federal student loans from doubling this year -- which would have hit nearly 7.5 million students with an average of $1,000 more on their loan payments.
"These steps will make a real difference in the lives of millions of Americans."
The Moving Ahead for Progress in the 21st Century Act -- known as MAP-21 -- reauthorizes taxes supporting the Highway Trust Fund through Sept. 30, 2016, authority to make expenditures from the fund through Sept. 30, 2014, and makes major reforms to surface transportation programs.
It also reauthorizes and reforms the National Flood Insurance Program through Sept. 30, 2017, and extends for one year the current interest rate of 3.4 percent on all new subsidized Federal Direct Stafford Loans for undergraduate students.
"This is so good for America," Transportation Secretary Ray LaHood said after the signing. "For all of us that have worked so hard on a transportation bill, it really is a great day. So many people are going to go to work as a result of this, building roads and bridges. And we're going to just make great progress. This is a great day, it really is. A lot of us have worked hard on this for 3 1/2 years."
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