Ask people about the problems on I-70 and most of them will mention trucks. Depending on your location along I-70, trucks account for about 21-32 percent of the traffic stream. And truck volumes are growing at a faster annual rate than that of automobiles. Heavy truck traffic affects not only the physical structure of the roadway, but also the safety of travel on it.

But that’s not the end of the story. Trucks are also tremendously important to Missouri’s economy, carrying 87 percent of the goods moving within the state. Anyone who buys milk and bread at the grocery store depends on a truck.

How Do We Handle Truck Traffic?

A number of suggestions for addressing truck traffic emerged during the First Tier Study. The I-70 Improvement Study considered a new parallel facility and a new toll road as options – assuming that they could remove a great deal of truck traffic from existing I-70. Through the study, those options were rejected largely because the public showed by a wide margin that it wanted to see MoDOT reinvest in the existing corridor. Both would have a significant negative impact on the natural and man-made environments, cutting through property never before disturbed by development. And both would cause substantial increases in operations costs, requiring MoDOT to maintain both the new facility and existing I-70.

Other suggestions included restricting trucks to two lanes, reducing speeds and better enforcement of speed limits. However, instituting restrictions on the current two-lanes could create significant hazards for entering and exiting vehicles and leave trucks little room to maneuver. Speed limit enforcement is the responsibility of the Missouri Highway Patrol.

Because of the input of the public, changes in the transportation industry and I-70's role in the nation's economy, MoDOT has initiated the Improve I-70 SEIS to see if rebuilding I-70 with truck only lanes is a better solution than simply rebuilding and widening.

Using the latest advances in pavement technology, MoDOT will ensure that new I-70 lanes withstand years of heavy truck travel. Additional lanes will themselves provide a safer environment for trucks and cars to co-exist. And access management measures at interchanges will help ensure smooth traffic flow.


In addition to the long-term measures mentioned above, MoDOT is taking action now to improve truck travel. Using the latest technology, MoDOT can allow safe and compliant commercial vehicles to bypass weigh stations, saving time and money and making roadway travel safer for everyone.

This new technology, called PrePass, is an electronic program that allows participating truck operators to be pre-screened as they approach weigh stations. Sensors at the weigh-station verify whether a truck driver has a satisfactory safety rating and is current on registration fees, fuel taxes and insurance. A small transponder attached to the driver’s windshield communicates with the system. Truck drivers see a green or red light and hear a tone inside the cab telling them to pass or stop. This all takes a matter of seconds, and assuming all is well, the drivers keep traveling.

Weigh stations using PrePass will also have weigh scales installed on highway lanes enabling them to weigh the trucks as they pass. Weigh-in-motion scales placed before the weigh stations allow PrePass-equipped trucks that are within weight limits to proceed.

Use of PrePass will relieve traffic congestion around weigh stations, meaning safer traveling conditions for everyone. Participating commercial vehicles will save valuable time and fuel, while improving their productivity. The increased productivity lowers shipping costs, ultimately translating into lower prices for goods shipped by truck. The technology also allows enforcement staff to concentrate their attention on non-compliant commercial carriers, saving state time and resources.

Currently 19 weigh stations in Missouri use, or are in the process of implementing the technology. These stations will monitor nearly all truck traffic entering the state.

PrePass is operated by Heavy Vehicle Electronic License Plate (HELP), Inc., a non-profit partnership between motor carriers and government agencies. HELP charges motor carriers 99 cents each time they can bypass a weigh station (up to $3.96 per day). This provides HELP with the funding needed to operate the system and provide it to the state at no cost.

The PrePass system has been installed in 23 other states, including most of Missouri’s neighboring states. Nationally, about 190,000 trucks are registered to use PrePass.