The collective lips of all engineers were licked when Obama started the "infrastructure stimulus" train out of the station. Any engineer likes the idea of infrastructure, because these are typically huge, expensive, long-term projects that don't require an extraordinary effort. Often the design takes a short amount of time, and the redesign makes the engineer a fortune. Plus, public projects can be pretty, with photo-friendly architectural features, because hey, if the client is the taxpayer then there is no one to complain.
However I think I should point out that massive infrastructure spending is going on right now and it isn't doing the economy any good. Ever since the bridge collapsed in Minneapolis in August 2007 the entire nation has been on a full-scale bridge inspection, repair and rebuilding blitz. State DOT's have reported as much as 40% of the nations bridges are structurally deficient or in need of repair. Many states have been granted as much as $1 billion to repair their bridges from 2008-2014, and some states report they could use 7 times that much and still not get all the work done.
That's $50 billion being pumped into infrastructure spending, and the economy didn't seem to notice much. If Obama wants to stimulate the economy, he should consider the Ramsey-Waller bailout plan, as well as increasing school funding and tax credits for manufacturing companies. Infractstructure spending (though decreasing unemployment - depending on whom you ask) really didn't boost the economy during the Depression, and it won't work this time either.