(LOUISIANA)--   Another mile marker has been passed on the way to building a new Mississippi River bridge at Louisiana. The public comment period on a replacement for the 84-year-old Champ Clark Bridge ended Friday.

The state’s project team will now respond to many of the comments and use them as part of the ongoing environmental study. The Missouri Department of Transportation expects to unveil potential routes next spring.

Several options were presented during a forum last month in Louisiana. Data such as cost factors, traffic patterns, flood plain management and home and business displacement are being considered.

So far, nothing’s set in stone. The biggest obstacle will be cost, which is estimated at 100 million dollars. While Missouri officials say a replacement remains a priority, the state hasn't set aside funding and there’s no timetable for completion.

An environmental study for a new structure continues. The bridge is one of the oldest still used for traffic between Minnesota and Tennessee.