The agreements provide the city with easement and overpass rights on the toll bridge that will be built by a joint venture created by CenterPoint Properties and cross both the Des Plaines River and a section of BNSF Railway railroad.
Assistant City Attorney Chris Regis noted the agreements apply to special conditions created by the construction project.
"There will be people working over the railroad. You will have to stop trains," Regis said.
The agreements also provide that Houbolt Road Extension Joint Venture pays for any railroad-related construction costs, according to a staff report.
Houbolt Road Extension will pay for construction, operation and maintenance of the bridge, according to a 99-year lease agreement with the city, which will own the bridge.
Construction is estimated to start in the spring.
A permit from the U.S. Coast Guard to build over the Des Plaines River and approval from the Illinois Commerce Commission is still needed.
Cost estimates for the project have ranged from $150 million to $200 million.
The complete project includes widening of Houbolt Road and a new interchange at Interstate 80.