The US Department of Transportation (USDOT) has announced grants of $511m for 46 transportation projects in 33 states and Puerto Rico from the third round of the TIGER programme.

The latest round of grants will allow communities to carry out critical, job-creating infrastructure projects including road and bridge improvements, transit upgrades, as well as freight, port and rail expansions.

USDOT secretary Ray LaHood said: "The overwhelming demand for these grants clearly shows that communities across the country can’t afford to wait any longer for congress to put Americans to work, building the transportation projects critical to our economic future."

Out of the $511m allocated, more than $150m will be invested in vital projects in rural areas.

48% of the funding will be used on road and bridge projects, including more than $64m Complete Streets projects, which is expected to give a boost to small businesses and benefit motorists, cyclists and pedestrians.

29% of the funding will support transit projects like the Westside Multimodal Transit Center in San Antonio, while 12% will be used to build port projects like the Port of New Orleans Rail Yard Improvements. Three grants have been approved for local governments.

The US Government is providing TIGER grants to those transportation projects of significant national or regional importance.

Developments are selected for grants depending on their ability to contribute to the long-term economic prosperity of the country, while priority is also given to projects that will create and preserve jobs quickly, giving a boost to the economy.

In 2009 and 2010, the US DOT received 2,400 applications amounting $76bn in TIGER I and TIGER II grant programmes, out of which 126 transport projects were selected.