Counties Impacted
St. Louis
Project Status
Planning Phase
Route Impacted
Missouri Route 21

Project Milestones

Draft conceptual plans

MoDOT creates initial plans for the project.

In Progress
Public Meeting

MoDOT holds a public meeting to discuss the conceptual plans with the public to determine if there are necessary adjustments or additional updates.  The public meeting for Route 21 is set for June 14, 2022. A virtual version of the public meeting will also be available until about the end of June.

Not Started
Right of Way process

The team starts work to determine and obtain the necessary easements or right of way to complete the process. 

Not Started
Project awarded

Once the necessary easements have been obtained, the project is put out for bid and awarded, pending commission approval, to the lowest qualified bidder.

Not Started
Construction begins

Once the project has been awarded and the contract signed, construction starts.  This is anticipated to be sometime in late summer 2023.

What is the current situation?

The Missouri Department of Transportation has a project scheduled to resurface Route 21 between Gravois (Route 30) and the Meramec River, starting in late 2023.  During that project, the department is also making updates to the roadway’s pedestrian facilities. The current raised shoulder originally intended for pedestrian use will be removed and replaced with proper sidewalks making them compliant with Americans with Disabilities Act requirements.

In addition, the department is looking at adding new crosswalks, removing another and constructing several updated pedestrian signals. The work includes maintenance to two bridges in St. Louis County, one over Gravois Creek and one over Grant’s Trail.

As a part of this work, the department is also rehabilitating or redecking 17 bridges on Route 21 in Jefferson County between Schenk Road near Otto and the Meramec River northwest of Arnold.  Specifics on the work on those bridges is still being determined at this time.  Resurfacing of the roadway in this area will be done in late 2023.

Where is the department updating pedestrian crossings?

The department is working with Metro to make sure that appropriate pedestrian crossings are in place for bus stops along the corridor.

What other signal improvements will be made?

The signals at Baptist Church Road, East Concord Road, Schuessler Road, Tesson Rise Drive/Cedar Plaza and Walden Ridge Drive will be upgraded to meet Americans with Disabilities requirements. Signals at Lutheran High School South, Reavis Road, Musick Avenue/Green Park Road, Concord School Road, Mattis Road, Kennerly Road and the ramps to northbound and southbound Route 141 will be updated. Signals at the ramps at I-270, Bauer Road, Butler Hill Road, Duessel Lane, Susson Hills Drive and Duchesne Parque Drive/Hagemen Road will be updated to include detection.

Which bridges in Jefferson County will be worked on?

This work includes rehabilitating or redecking 17 bridges along Route 21 in Jefferson County between the Meramec River northwest of Arnold and Schenk Road near Otto. Bridges include two areas where northbound and southbound Route 21 cross Old Route 21, the northbound and southbound Route 21 bridges over Heads Creek Road, Rock Creek, Lonedell Road and relocated Route M, a bridge over a ramp to Route 21 as well as the bridges over the route at Four Ridge Road, Old Route 21 in two locations and Rock Creek Road.  Work also includes guardrail updates on and near the bridges. Additional specifics on the work on those bridges is still being determined at this time, although current expectations are that one half of each bridge will be closed at a time. That will require one lane to be closed in each direction and traffic to be shifted into the remaining lanes.


What bike facilities will be included in this project?

Since traffic volumes along Route 21 are fairly high, Route 21 will remain signed to remind drivers to share the road with cyclists.

What are the impacts?

Crews will start work by updating sidewalks and signals.  That will take most of the time during the project.

During that work, there should be minimal impacts to drivers – they can expect one lane closed in either direction during non-peak traffic hours as crews work on sidewalks and driveways.  Business owners with multiple driveways will always have at least one access point into their business through construction.  Crews will work on half of the access point at a time when there is only one entrance/exit from a business.  Residential driveways are too small to complete one at a time – driveways will need to be closed for several days at a time.  We anticipate that the contractor will be able to share a general timeframe when they anticipate being in the area -- probably about a week or two in advance.

As crews work on the bridge over Grant’s Trail, the trail will need to be closed under the bridge for safety for short periods when work is underway overhead. 

Residents who currently use the raised shoulder along the roadway as additional parking will not be able to do so when the project is finished. Since that is considered a walking path, drivers should not be parking on it and forcing pedestrians to walk in the roadway.

Currently, expectations are that one half of each bridge along the corridor in Jefferson County will be closed at a time. That will require one lane to be closed in each direction and traffic to be shifted into the remaining lanes.

When all the sidewalk  and bridge work is completed, crews will resurface the roadway.  That will probably take place in 2025 and may include multiple lane closures during the night to avoid major impacts to the traveling public.