And probably other urban highways

https://www.wbez.org/stories/h...a7-a7f0-140d2e077a9c

"The project, which looks at the 180 cities that received funding through the Federal Highway Act, contends the system of roadways was designed in part to contain specific people — including Black, Brown, and low-income populations — into particular neighborhoods as well as encourage white flight to what would become more easily accessible suburbs.

“The American city was methodically hollowed out based on race,” he writes.

Building a vast roadway system with massive exchanges around the edge of downtown, he said, “was about depoliticizing the city center to quell these populations by eliminating them, to some extent. The result was the poorer people … got pushed out.”"

Planned or highways were built through cheaper property? or perfect hindsight?

I don't doubt it could be malice, but there could be another explanation.

This theory has been around for a while. While I’m sure it has some merit I suspect the end result had to do more with unintended consequences than anything else.

Running freeways through areas with low land values probably didn’t help.

tl;dr, but it has the ring of truth. The expression was urban renewal = negro removal.

I remember when it happened in my home town of Buffalo. The expressway sliced directly through the center of a grand boulevard that was largely African-American. But it also desecrated a lovely Olmsted-designed park on the north side. Something for everyone I suppose. There is now a movement to remove that highway, or at least put it underground.

As a fearless teenager I remember walking among the ruins of buildings demolished to build the highways.

Highway construction, and more generally urban renewal, may have had a racial element to it, but I think it had more to do with rich versus poor and the desires of the rich to improve their city environments. I know that highway planning has generally taken into account the cost of property acquisition in routing new roads - still does, for that matter, although the environmental reviews also play a substantial role.

The flight to the suburbs was going on long before the interstate highway system was even created. Witness the closer suburbs that grew up as trolley lines or commuter railroad service grew up in American cities. As originally proposed prior to WWII, the interstate highway system would not have even entered cities, rather skirting them and relying on intercepting existing road systems to deliver traffic into the cities. That changed as the system was envisaged in the postwar period as the automobile and the suburbs became a force that wanted road access into the heart of cities. Of course, urban planning forces like Robert Moses in NYC were all in favor of letting the car dictate the city plan. Most of the additions made to the original planning by the time the Interstate Highway Act of 1956 and its subsequent revisions were the incorporation of routes to penetrate the hearts of cities or to incorporate existing highways and expressways into the system.

Big Al