One of the busiest roadways in the Chicago area is going to get a lot more congested in the coming months – and years.

Beginning March 15, a $600 million reconstruction project on the Dan Ryan Expressway – also known as Interstate 90/94 – will begin. At the start of the project, half of the road’s lanes will be closed, and all of the traffic on the express lanes – an area where trucks are prohibited – will be rerouted to the local lanes.

The lane reductions are significant, running between 31st Street and Interstate 57.

Signs alerting drivers to “drastic Dan Ryan lane reductions” are already being posted on adjacent roadways, in hopes of moving some of the expressway’s 300,000 daily travelers onto alternate routes, according to the Chicago Tribune

The express lanes have an expected completion date of March 2007, at which point all traffic will then be rerouted onto them while the local lanes are rebuilt. The entire project is expected to be finished by late 2007.