The Federal Railroad Administration has taken action that will allow the full build-out of a high-speed rail corridor between Chicago and St. Louis.
The administration said Tuesday the Rock Island Corridor is the most efficient route between Joliet and Chicago. Officials also chose a route through Springfield that consolidates trains on the city's 10th Street corridor.
The decisions were the final step needed for environmental approval of the project.
Gov. Pat Quinn praised the action. He said design and construction work may begin once funding is available.
The $1.5 billion in improvements to the Illinois line are expected to enable speeds of 110 mph over 70 percent of the route by 2015.
That is expected to shave about an hour off the journey between Chicago and St. Louis.