Heavy trucks escaping road limits

Renegade truckers who pack illegally heavy loads and haulers who don't understand Minnesota's complex truck-weight laws inflict an estimated $30 million a year in damage to state roads, bridges and railroad crossings.

Yet state officials who oversee commercial vehicles are ill-equipped to deal with the problem, consultants hired by the state have concluded.

Tighter State Patrol budgets, along with legislation allowing heavier loads for some industries, have made it harder than ever to enforce truck size and weight laws. Despite steadily increasing truck traffic, State Patrol overweight citations have dropped 21 percent since 2002.

Making matters worse, truck-weight enforcement on most county and city roads is the responsibility of county sheriffs and local police -- and few have the training, staff or equipment for the job.

It's unknown whether excessive truck loads played a role in the Aug. 1 collapse of the Interstate 35W bridge. But the National Transportation Safety Board is analyzing factors that include structural fatigue.

Officials at the Minnesota Department of Transportation and the State Patrol say they have no idea whether overweight trucks had been regularly crossing the I-35W bridge.

Tickets for overweight trucks don't offer clues, either. The Star Tribune analyzed overweight citations issued by the State Patrol since Jan. 1, 1997, and found that just two tickets had been issued on I-35W in Hennepin County: one in 1997 and one in 2000.

"With the traffic volume on that corridor, it makes it very difficult for us to even conduct a traffic stop for a truck," said Capt. Ken Urquhart, commander of the State Patrol's Commercial Vehicle Enforcement section.

To nab more overweight trucks, MnDOT and the State Patrol are evaluating high-tech enforcement tools, including "weigh-in-motion" scales embedded in pavement and "virtual weigh stations." But the systems are expensive to buy and maintain.

Cecil Selness, MnDOT's director of freight and commercial-vehicle operations, said the agency has used embedded scales in roadways to conduct research on pavement design. But he said no such work had been conducted at the I-35W bridge, which MnDOT inspectors had rated "structurally deficient" since 1990.

Study highlighted problems

A study of overweight trucks conducted for MnDOT and the State Patrol by URS Corp., a San Francisco engineering firm that also studied the I-35W bridge before its collapse, recommended comprehensive changes to the state's truck weight enforcement program.

"Unfortunately, while the demand for compliance has been increasing, enforcement resources ... have steadily diminished," says the report, which was issued two years ago and cost $75,000. "This is in part due to state government budget cuts and increased operating expenses," it said.

URS recommended a four-phase strategic plan to increase truck-weight compliance by 10 percent, which it estimates would prevent about $3 million a year in damage.

Most truckers operate within the law. But even a small number of overweight trucks -- in the neighborhood of 1 to 3 percent -- can reduce pavement life by 25 percent or more, the URS report says. It did not evaluate the damage done to bridge structures because of the difficulty of calculating the effects that overweight trucks place on structural supports.

The study found that the state's fixed inspection stations "rarely find violators" and recommended installing more weigh-in-motion sensors in pavement. It suggested the establishment of a network of "virtual weigh stations" that would help the State Patrol target scofflaws on heavily traveled routes.

The state operates six permanent truck scales, the busiest of which is the St. Croix scale on westbound I-94 in Washington County. But the URS report says it has become increasingly difficult for the State Patrol to maintain staffing at the scales.

The St. Croix scale opened in 1987 with 25 people operating three shifts a day, it says. "They now operate only one shift each day with a staff of 4 to 5 people."

Urquhart said the State Patrol is hiring inspectors now, but they're not new positions. "We're just replacing the folks that have left ... in the last biennium," he said.

About 27 troopers and 65 commercial-vehicle inspectors statewide are involved in truck and bus safety issues, Urquhart said. Sometimes, he said, it seems as if the laws are stacked against the inspectors, who have to find a trooper or other law enforcement officer to legally make a traffic stop.

'I can't stop that truck'

"That means if I'm an inspector and I see a heavy truck going down the highway and he passes me, I cannot stop that truck," Urquhart said.

But troopers won't stop a truck unless it can be pulled off the highway safely. And rules restrict inspectors from ordering a truck to return to a scale if it would delay the driver for too long.

Fixed scales are ineffective at weight enforcement because truckers know where they are and can alert one another via citizens-band radio when the scales are operating, the URS study said.

Mark Berndt, a consultant who worked on a truck-weight study for MnDOT's Mankato district, said Montana found that about 1 percent of the trucks at its fixed scales were overweight. But the number jumped to 18 percent when the state quietly monitored trucks with weigh-in-motion scales.

Urquhart said the State Patrol has 50 portable scales at its disposal. Inspectors generally require four to six scales because each scale can weigh just one wheel at a time. Having to move scales, which weigh 35 pounds each, "becomes very labor intensive," he said.

Mobile scales produce results. Data from 2004 showed that less than 1 percent of the trucks weighed at Minnesota's fixed scales resulted in overweight citations. By contrast, 13.8 percent of those weighed on mobile scales received citations.

Evaluating weight-check tools

Selness said he wasn't ready to endorse the URS truck-weight compliance plan without testing the technology and evaluating maintenance costs. MnDOT now has a $171,452 contract with URS to run what it calls a virtual weigh-station demonstration project, he said.

In the meantime, MnDOT is promoting voluntary compliance by funding a training program that has drawn more than 2,000 participants from industry and local government agencies so far, said Greg Hayes, a retired trooper who developed it.

Wayne (Gib) Erickson, co-owner of a mill called Erickson Timber Products in Baudette, Minn., said he attended the program because he think's it's important. "There's nobody that we deal with or that delivers wood to us that wants to see anybody hauling heavy loads and doing any damage to the roads," he said.

Dan Browning • 612-673-4493

Dan Browning • dbrowning@startribune.com