Driving in Circles / Viaduct Street Roundabout Back on the Drawing Boards

By Pauline Masson –

Well, not exactly on the drawing board, but a Viaduct-Thornton-Hogan roundabout occupies the center of studies that are underway to update the five-entry, road network north of the I-44 exit-257 interchange.

It would be safe to say that no Pacific road has been studied more than Viaduct Street – the one-block-long roadway beneath I-44 that connects West Osage with Thornton Road and crosses the west bound I-44 exit and entry ramps, as well as Hogan Road.

At least twice, officials thought they were on target to build a roundabout to ease traffic and improve safety on Viaduct Street but backed away after resistance to the plan surfaced.

Now the City and MoDOT are again studying possible improvements on Viaduct Street with MoDOT pointing toward a roundabout.

At the Jan 3 board meeting aldermen approved an agreement with George L. Crawford & Associates, dba CBB to do an addition to recently completed Traffic Engineering Studies of Interstate 44 – Viaduct St. – Hogan Road – Thornton Road Interchange that MoDOT is requiring.

 In his Dec. 20 report to the board of aldermen, City Administrator Steve Roth said the CBB study had analyzed traffic volumes and considered two options for improving the intersection: traffic signals and a roundabout. 

“The roundabout is the preferred approach,” Roth said.

MoDOT, sold on roundabouts, touts their value on its webpage, which says roundabouts are a great alternative to a signalized intersection when a high volume of traffic needs to get through with the least amount of inconvenience. Signalized intersections have approximately 20-30 conflict points, or spots where vehicles could collide. Roundabouts reduce that number to eight, which can translate to as much as 76% fewer crashes, which also results in fewer crash-related injuries. View the Roundabout Handout to learn more.

Alderman James Cleeve voted to approve the additional traffic study to assure viability of the Viaduct Street improvement project, but said he believes a roundabout may be the worst possible reconstruction of the project.

In addition to the additional traffic studies, MoDOT is calling for an AutoTurn diagram to show a truck making all movements for all approaches in the roundabout. 

But the bigger issue may be the traffic signal at Osage that can backup traffic on Viaduct Street.

This was the final concern of retiring alderman Andy Nemeth who lives north of the conjested section of roads. During his six years as an alderman, Nemeth repeatedly called for safety measures in the high traffic area, which eventually prompted the city to improve signs, paint crosswalks on the street to alert motorists of pedestrians and install barricades to keep vehicles on the roadway.

As a parting reminder of challenges on Viaduct, Nemeth worried that the traffic signal at Osage could back-up traffic on Viaduct all the way to the proposed roundabout, preventing vehicles from exiting the circle.

This conjurs up the lilting refrain of the old Kingston Trio protest song when the Boston MTA raised the subway fair from a dime to 15 cents. A hapless chap named Charley boarded the train and handed in his dime but when he stood to get off the train the conductor said he owed another nickel. He couldn’t get off the train. He was stuck. His wife went to the station each day and handed him a sandwich through the window becaue he was doomed to Ride Forever Neath the Streets of Boston as The Man Who Never Returned.

Whimsey may not seem to be a serious enough tone for this subject, but the analogy holds. If the road ahead is backed up with traffic, the vehicles in the circle won’t be able to exit but will have to keep going around in circles like Charlie on the MTA.

This is at least the third time MoDOT has looked at installing a roundabout to improve traffic at the I-44 exit 257 interchange.

In 2001 MoDOT completed a $30 million I-44 resurfacing project that included widening West Osage and reconstructing the south half of the Viaduct Street interchange by relocating the eastbound I-44 ramps approximately one half mile west of Viaduct Street to Payne Street. Cost of the work on Pacific surface streets was $7.4 million. MoDOT engineer Judy Wagner said the project would help relieve traffic congestion and accommodate future traffic growth in Pacific. The preferred improvement for Viaduct Street was a roundabout that never materialized.

Thirteen years later, in 2014 MoDOT drew up plans for a single lane roundabout on Viaduct Street with five entries and five exits and wooed then mayor Jeff Palmore to endorse the roundabout with a snazzy video presentation. East West Gateway awarded the city a $1.8 million grant to build the roundabout but aldermen ultimately rejected the MoDOT plan and did the unthinkable, told East West Gateway to keep its money.

A May 2018 traffic study appeared to support the board’s decision to reject the roundabout. That study indicated that the proposed single lane roundabout would have been adequate for travel volumes of 2018, but not for much longer. The study showed that traffic had doubled between 2006  and 2018 and would double again by 2040.

Now the City and MoDOT are again trying to come up with a plan to ease traffic and improve safety in the cramped traffic complex. 

Roth said the city has not made a specific request for a grant to improve Viaduct and a possible roundabout. Preliminary cost estimate is $3 million. The city would have to pay a 20 percent match of $600,000. He said the City is not in a position to fund the full $600,000 match but the city could ask (roundabout loving) MoDOT to kick in $300,000 to share the local match.

We’ll hang around to see how this turns out.