Hank on 10/30/2013 12:49:13 PM:
Klondike Park near Augusta. Excellent developed park with a fishing lake, hiking trails, full camping facilities, etc. Immediately adjacent to the trail.
Also, Creve Couer Lake park near St. Charles. Very large lake with non-motorized boating, (sailboating, wakeboarding, canoeing etc. with rentals available). I don't think they allow camping / overnight uses but excellent day trip spot. About 2.5 miles from the Katy via separate bike lane on Page Avenue bridge.
Enjoy.