With nary a public comment or press release, it appears the City of St. Louis is set to transform the intersection of Kingshighway and Forest Park Parkway to an at-grade intersection. Thanks to significant funding from BJC and Washington University, construction is apparently set to begin as early as next month. All information about this project thus far is courtesy of the always excellent NextSTL. Read their article for all known information regarding the project.

The proposed changes at the intersection of Kingshighway and Forest Park Parkway has many drivers concerned about increased congestion and travel times. Traffic along Kingshighway can be punishing to get through during rush hours, today; bringing the Parkway to the same grade as Kingshighway threatens to make traffic worse and more difficult than it already is.

Of course, one of the main reasons the intersection is being brought to grade is to give vehicles on Kingshighway access to Forest Park Parkway towards Clayton. But is there a way to include this missing movement at the intersection without negatively affecting existing traffic conditions? Here’s one idea I drew up.

FPP Kingshighway Turn Ramp

So how does this design differ from the standard 4-way intersection? Two things in particular:

  • Grade-separated left-turn ramp from westbound Forest Park Avenue to southbound Kingshighway.
  • Prohibited left turns from eastbound Forest Park Parkway to northbound Kingshighway. Drivers wishing to make this turn would continue to exit at Lindell just as they do today.

It may cost a bit more, but by removing the Parkway’s left-turn movements from the intersection, these two changes allow for the simplification of the traffic signals from a standard 4-phase system to the 3-phase system in place at the intersection today allowing more green time for everyone.

Posted by Herbie Markwort

I like to write about transportation.