Updated

Capping a rare instance of congressional compromise, President Barack Obama signed a $12.3 billion water projects bill Tuesday, financing improvements ranging from a harbor expansion in Boston to flood control in Iowa and North Dakota.

Obama praised the work of Democrats and Republicans and said he hoped it set a pattern for agreement for more spending on capital works projects across the country.

"Right now we should be putting a lot more Americans back to work rebuilding our infrastructure," he said. "There are a lot of guys with hardhats sitting at home."

The new law will pay for 34 new projects over the next 10 years. Its price tag is half the amount of the last water projects bill seven years ago. Congressional leaders have praised the bill for containing no pet projects from lawmakers, the kind of targeted, congressionally directed spending that had angered the public and helped fuel the tea party movement.

All of the projects were recommended by the Army Corps of Engineers.

Obama singled out the bill's main negotiators -- Democratic Sen. Barbara Boxer of California and Republican Sen. David Vitter of Louisiana, Republican Rep. Bill Schuster of Pennsylvania and Democrat Nick Rahall of West Virginia.

"They set aside politics, they focused on what was important for the country and what was important for their communities," he said. "And as a consequence we have a piece of legislation that is really going to make a good difference."

He urged lawmakers to use the same spirit of compromise to act on a massive transportation bill. He warned that without action, 100,000 projects could come to a standstill, affecting 700,000 jobs.

"The fact that this bill received some bipartisan support I think hopefully sets a pattern for additional work," he said.

Though some conservative groups argued the bill still contained unnecessary spending, it had broad support from state and local officials and business groups such as the U.S. Chamber of Commerce.