I have never had a problem in East STL, but that route takes you through some pretty rough areas (brooklyn, etc.) Where are you coming from to get to Cahokia? If we can move you East a bit, There are nice roads that will take you to grafton via Belleville,Shiloh, Ofallon, to Edwardsville. In Edwardsville there is a great trail network that will drop you off at the river.

Heres a overnight loop I did last year from Glen Carbon showing 2 good ways across the river: http://maps.google.com/maps?ie=UTF8&...48322&t=h&z=10

Here is a file that will show you good roads to get from Ofallon to Edwardsville: http://maps.google.com/maps?ie=UTF8&...15604&t=h&z=13

Just a few options...