St. Louis is confusing in many places with signage, I've had several times I've randomly exited a highway and ended up in East St Louis versus staying on highways.
When I went back east after the family moved here, I tried the south route around St Louis. I followed a "To Illinois" sign and wound up on a 2 lane road leading to East St Louis. Not a happy camper.
In terms of the traffic count I mentioned, you'd likely still have some people take the same corridors beyond the 10% that exit downtown, you'd probably still have to account for some additional local traffic, like on 75 south someone might want to go to Utica Square, so that'd still be the faster corridor to take even though downtown isn't the destination. A percentage of travelers trying to go east west are probably still not going to divert and go straight through downtown, it's just going to take them a bit longer. There is also a percentage of trips that just disappear too and it's been documented in studies in other cities.
People would still take the same corridors one time if the IDL is removed until they learned the alternate routes. I would not anticipate through traffic choosing a non-express route more than once. Folks going to Utica Square etc will just have to accept the delays. But... those are not the through traffic. For them, downtown, Utica Square etc is the destination.
For 75, that plan proposes to rebuild Lansing and Madison. You'd likely have 2 lanes north south for each of those so 8 lanes north south total (versus 4/6 now as a highway). So you'd have two north south surface streets to absorb traffic and that could still easily service 30,000 to 40,000 cars per day between the two (just at 35-40 MPH instead of 60 MPH).
Again, depends on your mission. Going through or somewhere within "downtown" or nearby places. 35-40 MPH speed limits with traffic lights results in a lot slower speeds, ref: S Memorial. I would definitely avoid Tulsa in those conditions if I only wanted to get through.
Right now the 75 and Tisdale corridor don't have more than 35,000 cars per day using it in the busiest spots in/near downtown. So for 75 & the Tisdale the street grid that would be rebuilt could carry 100% of the current needs of traffic. Now some will divert to the west corridor I outline in the previous maps, just because they can drive faster speeds if their end destination is not local. The traffic studies on the Gilcrease from OTA suggest that less than 10,000 cars per day will be using that southeast portion they are completing now. So even if 10,000 or 20,000 cars divert to that corridor it's still probably going to be less than 50% of capacity.
Southeast portion of the Gilcrease? SW maybe? If we get rid of the IDL, the Gilcrease will experience a lot more traffic than if we keep the IDL.
244 is the only route that would require the redistribution of some cars as 70,000-80,000 cars per day just aren't going to take a city street. You'd still have multiple new east west routes on this corridor that could carry 30,000 to 40,000 cars each once the street grid is finished though. Admiral for example would be rebuilt and would go all the way through, 1st Street, etc. would all be able to absorb traffic too and would all have through access now. A percentage of trips would just go away, so only 30,000 to 40,000 at max might have to be absorbed onto other regional highway routes and would be distributed out along the north or south options in the maps I posted. I-44 for example could easily handle 125,000 to 150,000 cars per day or more and is not even close to that capacity. Gilcrease might eventually need to be expanded to 3 lanes each along the northern loop, but even in it's current capacity it only has 30,000 cars per day using it in the busiest spot by the airport. It can easily service 70,000 cars per day in it's current form. It's important to remember that given it's regional traffic it will be distributed out through the day versus a significant amount of it added to rush hour traffic.
I disagree that ONLY 244 would require redistribution. While the Tisdale and 75 don't carry tons of traffic, combined they carry a lot. What
new multiple east-west routes? I-44 already exists. The Creek Turnpike already exists. Completing the Gilcrease is the only new route. If you are only talking about highways to downtown, OK. Some trips would just go away because people don't want to put up with traffic unless the trip is necessary. The Maps you posted seemed to ignore traffic going south on 75 south of I-244. I don't know the capacity of 1-44 after the construction is finished. I am willing to ignore transients. Gilcrease around the airport at 30,000/day plus diverted traffic... hummm.
We forget how much traffic a properly functioning street grid can handle. Really what we did is when we cut off access of streets like Madison and Lansing and others, we just forced that traffic onto a highway when 244 cut off many north south streets. The highway was never needed in the first place. It's still not needed now if the street grid is rebuilt. 75 did the same thing by cutting off east west flow of Admiral and other, all that traffic was then funneled onto 244 and that's why a lot of businesses died in this area.
I don't think we forget, we choose to take a different route. Again, is the mission to go downtown or go around. If I have no interest in stopping downtown (or even a small town), give me a way around. I am not going to spend any money just because you slow me down to "appreciate" your downtown. If you are a small town and I want lunch, or whatever, I'll take the Business Route. Do you really want me beating up your streets when I have no intention of spending any money in your town? Let the Feds pay for the bypass.
UCAT is a complicated issue, frankly I think the urban renewal authority really just wanted to get rid of the rest of Greenwood and used the cover of we're going to build a big university as the reason to justify it to the public. Ultimately most universities built in other locations so then all the land set aside just sat vacant because OSU wasn't that interested in building out a big campus in Tulsa for a long time.
Have to agree there.
The parking lot growth wasn't directly because of the IDL, but the IDL facilitated the commuting and car culture of Tulsa which is what resulted in many owners downtown thinking it was more valuable to knock over buildings for surface parking than it was to preserve buildings. So they're all intertwined a bit. If we hadn't built the IDL and decided that we shouldn't sacrifice buildings and homes for regional travelers and the suburban commuter I do wonder how different the city would be today.
City taxes probably were an influence too. Tulsa wasn't going to stop suburbia any more than any other city. I believe that if the Gilcrease and other big by-passes had been built before I-244, the result to downtown would have been the same. Downtown cities are experiencing a resurgence but in the 60s and 70s no one was going to stop suburbia.