MSNBC.com does a real public service by publishing this State-by-state list of deficient or obsolete bridges. A deficient bridge is what it sounds like; obsolete means that while the bridge doesn't have major maintenance issues, the design isn't sufficient for modern traffic volumes.
Not surprisingly, the North-east, with the oldest infrastructure and a vicious freeze-thaw-heat cycle does worst overall, although the Midwest isn't doing great. Florida, being a fast-growth Sunbelt state has more troubles with “obsolete” bridges (is every bridge in Miami on that list?) than deficient ones.