Write Up:

Recurring congestion comes at regular times, although the traffic jams are not necessarily consistent day-to-day. Nonrecurring congestion is an unexpected traffic crash or natural disaster that affects traffic flow. When either occurs, the time required for a given trip becomes unpredictable. This unreliability is costly for commuters and truck drivers moving goods, which results in higher prices to consumers.

While the desired trend for both costs is downward, challenges exist in Missouri’s metropolitan regions and major truck freight corridors that continue to threaten this positive outcome. A comprehensive look at congestion that goes beyond typical solutions of adding capacity is needed. Using smarter technology to help guide motorists is a must. Still, the desired outcome is to lower congestion costs and demonstrate that traffic is moving more efficiently.

This report looks at the 2016 to 2019 cost of congestion in the urban areas of Kansas City and St. Louis, as well as rural I-44 and I-70 across the state. The 2019 target for statewide congestion cost was $494 million. The actual calculation from the Regional Integrated Transportation Information System data for 2019 was $750 million.

Congestion costs in Kansas City rose each year from 2016 to 2019.  St. Louis congestion costs peaked in 2017 and dropped in 2018, rebounding in 2019 but remained below the 2017 peak.  Vehicle miles travelled statewide have continued to increase over the time period reflecting a 1.3% increase between 2016 and 2019.  Statewide congestion costs rose 15% between 2016 and 2019. 

Traffic congestion is widely viewed as a growing problem in many urban areas because the overall volume of vehicular traffic in those locations (based on vehicle miles travelled) continues to grow faster than the overall capacity of the transportation system.  Increased truck freight volumes continue to impact the rural interstate system as well.  

Purpose of the Measure:

This measure tracks the annual cost and impact of traffic congestion to motorists for user delays and vehicle miles traveled on select routes in the St. Louis and Kansas City regions as well as rural sections of Interstates 44 & 70.  

Measurement and Data Collection:

A reporting tool available in the Regional Integrated Transportation Information System looks at user delay costs. This data, in combination with industry standard costs for passenger cars and trucks, reflects the overall costs of congestion. RITIS also includes historic data so trend lines can be tracked and evaluated. The unit cost per passenger car is $19.14 per hour and is obtained from the US Bureau of Labor Statistics. The unit cost per truck is $71.78 obtained from the American Transportation Research Institute, which specializes in tracking freight mobility and provides the best source of data related to freight costs. For previous reporting, the department used data provided by the TTI, which annually produces the Urban Mobility Report. The target for this measure is updated annually in April and is established by projecting a 10% improvement over a four-year average.