MoDOT's Clean Air Connection

The Missouri Department of Transportation has been actively involved in St. Louis region clean air activities for more than 25 years.



In 1995, MoDOT was invited to join the St. Louis Regional Clean Air Partnership, or SLRCAP. SLRCAP is a coalition of business, industry, legislative, health and community organizations formed to develop and implement voluntary plans that encourage reductions in ozone-causing emissions. The invitation was a great opportunity for MoDOT to help with the regions air quality.



Not only is ozone pollution extremely unhealthy, it hurts the economic viability of our region and can even threaten our federal highway funding. We decided to join forces with the other SLRCAP members to positively impact our region's air quality. We also opted to take on a lead role by acting as a liaison to other government groups.



MoDOT's commitment to help improve our region's air quality involves five components:

1. Modification of Daily Operations

On days when air quality is forecasted to approach unhealthy levels, we change our internal operations so as not to cause excess ozone-causing emissions. One of the most common sources of ozone-causing emissions is the automobile, so the main component of our operational changes involves reducing maintenance operations that may cause traffic congestion, except for safety reasons, on forecasted red ozone days.

The longer an automobile has to sit in traffic, the more it idles and the more ozone-causing emissions it produces. Any routine maintenance operation on our region's state highways that causes congestion will be postponed on forecasted red ozone days. Permanent lane closures on contracted highway construction will not be lifted on red days because of logistics. When feasible, our inspectors will work with contractors to lessen the impact to motorists on red days.



2. Employee Action

As much as MoDOT internal operations can impact the region's air quality, so, too, can our own personal actions. For instance, has an extensive car-pooling program in cooperation with Ridefinders and our employees are heavily encouraged to find alternative modes of transportation (especially during the ozone season). The ozone forecast is disseminated daily to MoDOT employees, along with tips to improve air quality. Then, each individual employee can also positively impact the region in which we live and work.



3. Traveler Information

During the ozone forecasting season, MoDOT eight solar-powered portable message boards to display the daily ozone forecast. These message boards are also used for traveler information in times of major incidents on the highways to help alleviate congestion. Over half of a million motorists daily have the opportunity to view these messages and have the opportunity to positively impact the region's air quality. Their locations are:

  • Westbound I-44 east of Bowles Avenue -
  • Westbound I-64 east of Mason Road -
  • Southbound I-55 south of Butler Hill Road -
  • Westbound I-70 east of the Blanchette Bridge -
  • Southbound I-270 south of I-44 -
  • Eastbound I-270 east of Rte. 370 -
  • Eastbound I-270 at McDonnell -
  • Eastbound I-70 at Fifth Street -

In addition to these smaller portable message boards providing daily ozone information, MoDOT also uses its large stationary message boards on red ozone days. MoDOT also places a warning message on its real-time traffic information website:  traveler.modot.org.  With these three components being used for traveler information, MoDOT has the potential to reach over a million motorists during Ozone alerts.  

4. Community Leadership

Our region has hundreds of government agencies and organizations. Each group and/or agency impacts thousands of citizens by their actions. MoDOT acts as a liaison to these groups to provide information about clean air and advise them on activities they can do to help improve air quality.



5. Gateway Guide Program and Congestion Management

MoDOT is committed to managing the St. Louis Metro area highways in order to reduce congestion. This is achieved through a multi-agency Intelligent Transportation program called Gateway Guide. Gateway Guide is responsible for incident management on the region's interstate highways through Emergency Response teams with the help of high-tech communications equipment. This technology also allows MoDOT to provide traveler information through the program as well. These efforts reduce congestion, which translates into reduced ozone pollution.  In addition, MoDOT carries out a yearly traffic signal optimization program on arterial corridors.  Updating timing plans and coordination across designated corridors reduces emissions by decreasing travel times and reducing stops and delays on state routes.