Idaho’s fourth interstate weigh station went wireless last month, as state officials updated an existing facility southeast of Pocatello with technology making it easier for long-haulers to keep on trucking — and saving them and the state money along the way.
In the latest change, announced on Tuesday, Feb. 7, state transportation officials have updated the state’s Inkom Port of Entry (POE) on Interstate 15 with new Weigh-in-Motion (WIM)/Automatic Vehicle Identification (AVI) tech.
New to Inkom, the technology was first installed at scales in the East Boise area at least a decade ago, Reymundo Rodriguez, compliance manager for the Idaho Transportation Department (ITD), told Government Technology.
WIM/AVI technology is still going in around the country, though many states have some degree of it in place. Idaho’s increased usage brings it more in line with adopters like Utah and California, where John Liu, Caltrans' deputy director of maintenance and operations, said the state has had a version in place “for decades.”
Following the national belt-tightening of the Great Recession, Idaho has resumed its rollout, bringing it to POEs near Huetter in Coeur d'Alene, and to Lewiston.
The state finished updating Inkom in January and plans to install WIM/AVI technology at the Sage Junction POE in eastern Idaho, about 60 miles south of the Montana border, after the start of the new fiscal year July 1.
Funding for the technology was divided between a grant from the Federal Motor Carrier Safety Administration, and $596,000 in matching funds from the state.
Its effects, officials said, are dramatic — allowing the state to scan loaded semi-trucks on the highway at cruising speed, where previously all trucks had to drive through the scales and slow to around 5 miles per hour.
The technology has two main parts. To weigh trucks, construction crews buried a WIM sensor “loop” under the surface of the slow lanes on north and southbound I-15. When trucks drive over the loop, it instantly registers their weight and axle configuration, and computers cross-check the information in a database to ensure trailers are correct and within weight restrictions.
Virtually simultaneously, AVI license plate readers identify trucks by their plate numbers, and computers at the scales are able to confirm the company, the driver and a snapshot of the vehicle’s safety record from a federal database. State computers also retrieve vehicle registration information and any permits the truck has for its weight or configuration to exceed legal limits.
All this happens within seconds.
Truck drivers who pass get a green light on the small transponder device in their cabs. For those whose trucks don't have transponders, illuminated highway signs tell them to keep driving. Trucks whose companies have safety questions or whose loads don’t match state and federal information get a red light on their transponder or a message on the sign telling them to pull into the scales.
“This is a major change in the way that we’re doing business. Before, we were having to bring every truck in,” said David Hankla, who manages ITD ports of entry in eastern and southeastern Idaho. “It will help traffic a lot and it will help industry. Industry wants to keep rolling and we want them to keep rolling too.”
In a statement, ITD Director Brian Ness described the state as "committed to keeping business moving," and called WIM a "great example of making investments that benefit commerce and all of the traveling public."
"I think the final product shows that we knocked it out of the park," Ness said.
While Idaho’s older scales aren’t known to have caused any accidents, during peak hauling times —including around the holidays — trucks would fill the scales and state employees would have to temporarily close them to avoid having traffic back up onto the highway.
“The only ones we will bring in now are the ones where there’s something we need to see, the weights don’t match or just a random [selection],” Hankla said.
The exact impact of WIM/AVI on state resources isn’t known, but Rodriguez said it has allowed Idaho to take a closer look at more trucks without hiring more staff.
“That’s the thing I think you’ll find, that state agencies run lean and mean,” Rodriguez said. “This allows us to be more effective with the resources we have because now we’re focused on those vehicles that have to come in.”
Idaho officials have a more specific estimate of WIM/AVI’s effect on commercial vehicles, local economies and the public. Updating the Inkom weigh station, which is used by about 3,100 commercial vehicles a day, is expected to create a $2.1 million value.
Chad Sheppick, director of the Utah Department of Transportation’s Motor Carrier Division, told Government Technology that his state has had WIM/AVI technology in place for eight to 10 years at seven locations. It saves carriers more than $10 million annually, Sheppick said.
Additionally, the Federal Motor Carrier Safety Administration estimates that carriers save $8.68 per bypass.
From 1993 through 2016, PrePass, a weigh station bypass site infrastructure that includes transponders and has equipment in use at 315 sites in 32 states, has saved carriers $5.4 billion, including $294 million in fuel savings, said Andrew Johnson, chief marketing officer for the nonprofit that produces PrePass, via email.
A transponder is a small device that automatically sends or receives a radio signal. In the trucking industry, each transponder typically identifies a specific truck at weigh stations.
After its Sage Junction installation, Rodriguez said Idaho will likely install WIM/AVI on Interstate 84 near Cotterell, Idaho.
The state also makes limited usage of virtual WIM near Ashton, and is in the planning stages to install that technology near Arco, he said.
As its name suggests, virtual WIM uses the embedded technology to monitor traffic in remote areas wirelessly without staffers on-site. If issues arise, the state then sends personnel.
“It can be an indicator to send roving personnel out there if we see any problem vehicles coming through or coming through heavy,” Rodriguez said.