Techncally, you're correct davver. However, this connection between the River Mississippi and Lake Michigan isn't natural - it occurs because of a canal that was built between the closest points of the Mississippi River and the Chicago River, which flows through the heart of America's 2nd city. Interestingly enough, those Chicagoans were a smart bunch of people - at the turn of the last century, they found a way to actually REVERSE the flow of the Chicago River! Whereby it used to flow into Lake Michigan (and deposit all the sewerage and pollution pumped into the river and the mouth of the river), now all the pollution and sewerage flow from Chicago to the canal and eventually onto the River Mississippi. But the short answer to your question is yes.