GRANGER, IND. — A section of the Indiana Toll Road, the 157-mile highway that stretches across the northern portion of the state between Ohio and Illinois, will undergo $200 million in improvements including new asphalt and bridge work, the company that leases it announced Tuesday.



Work will begin next month on a 70-mile stretch of the road from mile marker 20 in Lake Station to mile marker 93 in Elkhart, said Ken Daley, chief executive of the Indiana Toll Road Concession Co. He called it "a critical investment in safety and service on the Indiana Toll Road."



The project will include removing the existing asphalt down to the concrete base and replacing it with a 5-inch layer of new asphalt. It also calls for improvements to interchanges, replacing road shoulders, work on 53 bridges and the installation of fiber-optic cable aimed at improving information available to drivers.



Gov. Mike Pence said the work, which will be paid for by the Indiana Toll Road Concession Co., is the largest project on the road since it was completed in 1956.



"The fact that we're able to do it without burdening taxpayers in Indiana, without burdening motorists on the Toll Road, I think is a real testament to this project," Pence said.



The work, which is expected to create about 300 jobs, will be done by Rieth-Riley Construction Co. The project will be done in three- to six-mile sections, and at least one lane of traffic in each direction will be kept open while the work goes on.



"We've planned as much as we can to ensure that we maintain a level of service to customers," Daley said. "Our customers pay to use this road. It's our obligation to them to do the very best we can."



When the Australian investment consortium IFM Investors, which owns the lease on the Toll Road for another 65 years, said in May when it announced that it had closed on its $5.72 billion purchase of the lease that it planned to make $260 million in capital improvements on the highway over the next five years.



The work is scheduled to be completed by December 2017.