The Minnesota Department of Transportation is testing new technology that is giving state troopers a better chance to catch carpool lane cheats.

Nearly one in seven motorists illegally uses the high-occupancy vehicle (HOV) lanes that during rush hours are reserved for carpools of two or more people, buses, motorcycles and solo drivers who pay to use them. Through September, the State Patrol has issued nearly 3,500 citations to motorists who have flouted the law, compared with 2,933 written in all of 2018.

“It’s a big problem,” said Lt. Paul Stricker of the Minnesota State Patrol. “We have a high violation rate, and we can’t get everybody.”

A system of beacons and detectors being used during morning rush hours on Interstates 35W and 35E could help the patrol nab scofflaws, and better yet, deter violators from entering the lanes, which are in effect from 6 to 10 a.m., said Sue Gergen, a MnPass spokeswoman.

As a driver passes by, an antenna seeks to read a MnPass tag. If a driver has a valid tag, a blue light flashes. An amber light flashes if the antenna does not detect a tag. In the latter case, a trooper must determine that a vehicle has only one occupant before making a traffic stop. The trooper can then check to see if the driver has a valid tag and that it was set to allow MnDOT to collect tolls. Troopers can write a ticket if a driver does not have a tag or has it turned off.

“We see that quite a bit; we see people slide the lever over,” Stricker said, noting the he recently stopped a solo driver who had a tag but had not paid a toll since February. “They are not paying to use the lane.”

Others try to evade troopers by making it look like they qualify as a carpool. Drivers have stuffed rubber baby dolls in car seats and put hooded sweatshirts over skeletons, Stricker said.

“You have to give them credit for ingenuity,” he said.

That has not stopped the eight troopers who enforce the lanes from writing citations that come with a fine of up to $300. But for every ticket written, scores of other drivers get away with the infraction. Law-abiding drivers have complained, a reason MnDOT is trying to improve enforcement, Gergen said.

MnPass is designed to keep traffic flowing at 50 mph or faster. Solo drivers pay 50 cents to $8 per trip depending on congestion. With more vehicles in the lanes marked with a diamond, speeds slow down, and that defeats the purpose of congestion relief.

MnDOT is testing the system only during morning rush hours on northbound I-35W at County Road 42 and at Hwy. 13 in Burnsville. Another test is being conducted on southbound I-35E at Arlington Avenue in St. Paul. The pilot will run through summer 2020 to give MnDOT enough time to determine the system’s ability to identify tags and to set the right brightness of the beacons, Gergen said.

Stricker said the system has been working close to 90% reliability since it went live in midsummer. The technology also will be a boon during the winter months when it’s dark and hard to see inside of vehicles, he said.

The beacons, which cost MnDOT about $30,000, replace an infrared camera system tested in 2017. That system snapped photos of drivers in the MnPass lane who passed by a detector that did not register a toll-collecting tag. That system was scrapped due to its high cost, Gergen said.

If the beacons prove beneficial, it could be deployed at 40 locations across the MnPass lanes on I-35W, 35E and 394, Stricker said.

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