Expedition! St. Louis: The City Fights Back
I saw this video on Youtube a few days ago. It is a documentary from 1960 on the successes of urban renewal, the ongoing Mill Creek Valley "Redevelopment", and the push to "surgically" remove other areas of the city such as Kosciusko.
What's interesting to me is that they also note concerns of a falling city population, which by 1960 was in its first decade. It seems like they were thinking the spread of the slums made people leave the city so they tried to get rid of the slums altogether.
Here's two things I'm theorizing in my head: The slums were simply moved to other areas of the city in a vertical form and the expressways' impact on population dynamics. For instance, much of the Mill Creek population was moved to Pruitt-Igoe and Cochran Gardens. At least Mill Creek was a neighborhood with a street network. These projects were walled off, isolated fortresses of stacked low income residents. Quickly they began to fail and the neighboring communities didn't want to live near these "projects" which were dropped on them. in 1960, the Interregional, or I-44 from Gravois to Washington was complete and I believe the Mark Twain, or I-70, was nearing or already completed. This made the suburbs of north county, as seen by city dwellers as open prairie countryside, much more affordable and convenient to live in.
I think it was more than the "spread" of slums that caused the mass population exodus of the city since 1950. I think the city's efforts of removing neighborhoods and putting the people in apartment towers dropped on other neighborhoods accentuated the population exodus. And on top of that, the new expressways, notably the Mark Twain that shoots off into north county, sucked more of the population out of the city.