I don't know of a town called St. Lake. U.S. 40 parallels I-70 and is I-70 for many stretches of the trip from Baltimore to Denver. When it separates from I-70 for a distance in MO, it's just a 2 lane highway winding through small towns and taking much longer than going on I-70. Also through Kansas, much of the U.S. 40 is now I-70 and the old route 40 is called just that, "Old Highway 40" which is now maintained by the state, not U.S. highway dept. At Oakley, KS U.S. 40 splits away from I-70 for a time, then joins into U.S. 287 at Kit Carson, CO and joins in to I-70 again at Limon, CO.
If you use Google Maps and drop the little yellow man symbol (lower right corner) onto U.S. 40, you'll see a 360º photo of that spot on the highway. You can then click the white arrow in the direction you wish to explore and 'travel' down the road through your computer screen.
Bob & Donna
'98 Gulf Stream Sun Voyager DP being pushed by a '00 Beetle TDI