Certainly this has been discussed, but the search function is slower than a slow thing.
I know WHY Chicago chose to reverse the flow of the Chicago river, but I want to know HOW it continues to flow the wrong way. Has nature taken over at this point or is there some sort of mechanism taking care of it?
The Sanitary Canal was built
O…k. I’m still a bit confused. I was under the impression that locks only affected the level of the water, not the flow. It seems to me like water would have to be constantly ‘pushed’ via air or something to keep it going the wrong way. IT’S TOTALLY AGAINST NATURE! DO YOU HEAR ME?
Locks allow you to control the level of the water within them by controlling the flow.
Imagine a plastic bottle with two holes punched in it at slightly different heights on opposite sides. Water’s running into the bottle from the top and all of it goes out of the lower hole. Plug the lower hole, the water level rises until it gets to the upper hole and then goes out there.
The bottle is the river with rain and waste water flowing into it. The lower hole is the mouth of the Chicago River at the lake. Plugging that hole is closing the locks. The upper hole is the sanitary canal.
Oh! Okay. The river is actually blocked from flowing into Lake Michigan, and therefore flows the “wrong way” through the canal over the “low summit” and south. With Chicago’s sewage.
(Oh boy. The people along the Mississippi or wherever musta loved that one…)
I always thought that the canal diggings were low enough that the water flowed out of Lake Michigan naturally. Thus competing with, eventually, Niagara Falls. 
Book titles on this subject?
“Flow” implies a much greater speed than actually occurs. It may be more accurate to say the Chicago River “oozes” rather than flows.
Still, it’s better than a century ago when the river was rumored to achieve jello-like consistency on occassion. And occassionally catch fire.
Oh, yeah, you never heard such whining…! Actually, the folks downstream are still not very happy about it.
Ain’t nuthin’ natural ‘bout dat river no mo’
It’s all done with smoke and mirrors.
Just some more Chicago trivia - everything east of Michigan avenue in the Loop area is artificial landfill, and “ground level” in Grant Park is really more like 8-12 feet about the natural ground level. At one point they literally jacked up every block in the Loop, threw some new brick foundations under the buildings, and rebuilt all the streets.
These are just some of the reasons why I laugh hysterically whenever I hear someone going on about preserving “nature” in the downtown area.
A high school classmate of mine spent most of WWII ferrying landing craft built in Chicago, or Gary, IN down to Mobile, Alabama. They started out though the (ahem) Chicago Sanitary and Ship canal, down to a short stretch of the Des Plaines, the Illinois to the Mississippi and the Ohio, thence down the Tennesee, to canals to the Tombigbee, and on to Mobile. Made the Yellow Brick Road seem prosaic.
Maybe if the river flowed back to the way it used to be, all the evils of the Chicago administration would dissappear?
Yeah, but that would leave the city drinking it’s own… >ahem<
Let me just point out that the water intakes for the city water systems are in Lake Michgan not that far from the Chicago river. Typhoid deaths, among others, dropped notably when the reversed the river. Hence the “sanitary” in “Sanitary and Ship Canal”
If they opened the locks out in the Chicago Harbor by the Coast Guard station, there would be more flow “down” the Chicago River. During the big drought in the '80’s (??), several midwestern governors asked Illinois to open the locks and get some Great Lakes water into the Mississippi to refloat the stranded shipping. Illinois politely refused.
[hijack]If you define an island to be land surrounded completely by water, the Chicago River makes The Eastern United States, the Maritime Provinces and part of Quebec an island since it connects the Saint Lawrence Seaway with the Mississippi Watershed.[/hijack]
The fallacy in that reasoning is that there are many more rivers in that “land.” So the area described would contain thousands of islands.