Maybe the CTA could look and learn?  The Western Avenue traffic flyover at Belmont put an end to development for the surrounding commercial/residential community.  50+ years later, they’re finally tearing it down.

Western & Belmont Viaduct to Vanish, 1.3 Miles of Wider Sidewalks Planned
Streetsblog Chicago, 6/10/14

The Chicago Department of Transportation plans to tear down the structurally deficient 52-year-old viaduct that lifts traffic on Western Avenue over the intersection of Belmont and Clybourn. Instead of a gloomy concrete interchange walling off the edge of Roscoe Village, a more conventional surface-level intersection could be built as soon as 2016.