SJK from Saint Louis, MO on 6/1/2012 8:36:42 AM:
There is a seperate bike/pedestrian lane at the Page Avenue bridge that will dump you out on the Katy at MM 43. However, that is about a 14 mile urban hike to Creve Coeur park and this bridge from the Amtrak station in Kirkwood. If you are somewhat flexible with your schedule, then I think you could get a shuttle in Clinton and get to St. Charles for $50-$60. You can look at/utilize the "Share a Shuttle" link on this site's home page to work that out. This same home page also has links to the Katy hikes that Bonnie mentions under trip reports that were done by a couple of different individuals a few years back.