Perhaps nothing steams rush-hour motorists more than seeing cheating drivers zip along in the MnPass lane. You know, the solo drivers who look to see that police are not watching, then high-tail it into the fast lane to escape gridlock.

Starting Wednesday, more cops will be watching.

In a new two-year agreement, the Minnesota Department of Transportation will pay the State Patrol $2.6 million to dedicate six officers whose primary duties will be to enforce the rules of the diamond lanes on Interstate 35W, I-35E and I-394. During peak hours, the special lanes are reserved for buses, motorcycles and carpools with two or more occupants, or solo drivers who pay a fee to use them.

But as traffic congestion worsens — it jumped by 2 percentage points in 2015 over the previous year, according to a recent MnDOT report — the number of highway robbers who avoid paying those fees have become rampant as many drivers are willing to take the risk of not getting caught.

"It really is a problem," said MnDOT spokeswoman Bobbie Dahlke. "MnPass is meant to provide congestion relief for those in the lane, and if we have violators, that compromises the integrity of the system."

About 7 percent of drivers who use the express lanes on I-35W between downtown Minneapolis and Burnsville and I-394 between downtown Minneapolis and the western suburbs during the morning and afternoon commutes are there illegally, according to recent estimates from MnDOT. About 18,800 motorists legally use MnPass lanes on I-35W and I-394 each weekday. The state doesn't have data for I-35E, which added the high occupancy toll (HOT) lane at the beginning of the year.

The high numbers of cheaters led to the partnership, Dahlke said.

"I'll be happy when I see it," Ann Jacobs Ritchie, of Plymouth, said about the enforcement. "I use the MnPass from Highway 12/394 to the 94 tunnel and it makes me so mad when people are in the lane and don't have a MnPass. It's just frustrating."

MnPass lanes are designed to keep traffic flowing at least at 50 miles per hour. Motorists pay between 50 cents and $8.00 for each MnPass trip, depending on congestion.

When operating optimally, the metro area's three HOT lanes provide for consistent speeds and trip times, while reducing congestion in the free lanes. But when violators enter, the diamond lane bogs down, Dahlke said.

"Every single morning and evening I see people without multiple passengers or a transponder using the lane," said Lindsay Campbell, who wrote on the Star Tribune's Facebook page seeking comments about cheats. Campbell would not mind a system that allows cameras to snap photos of offending drivers and mail them a ticket. "Sometimes I wish instant karma on them and look around for law enforcement to pull them over. It's not fair for the rest of the citizens that abide by the rules/laws."

Troopers issued 2,678 citations to MnPass lane violators in 2013. In 2014, troopers issued 2,291 tickets and 2,851 last year, according to the Department of Public Safety. Fines range from $120 to $200, depending on the county where the ticket was issued and additional court fines.

In the past, a pool of 20 troopers patrolled the three MnPass lanes on overtime, meaning patrols were not always monitoring the HOT lane's usage. Under the new arrangement, patrols specifically dedicated to enforcing the lanes will ratchet up the efforts to catch scofflaws by using a combination of static and mobile techniques, including driving in or alongside the MnPass lanes and possibly doing saturations.

"It happens enough that we need to be doing enforcement; there is a need for it," said Lt. Robert Zak of the State Patrol. "We've always enforced the HOT lane, but now it will be a primary responsibility."

The money to pay for the extra patrols will come from proceeds generated from MnPass subscriptions and revenue, not from general MnDOT funds.

As of Monday, there were 30,000 MnPass subscribers, up from 26,200 at this time last year, Dahlke said.

By 2028, MnDOT suggests that metro area highways and freeways may be congested close to 30 percent of the time during the hours of 5 and 10 a.m. and 2 and 7 p.m. on weekdays, the hours that MnPass lanes are in effect.

In addition to looking for motorists trying to sneak by, patrols dedicated to the MnPass lanes will also be looking for drivers who cross the double white lines separating the diamond lanes from the general traffic lanes along with drivers who speed, text and don't wear their seat belt.

"All the rules of the road still apply," Zak said. "It's just not worth the risk."

Tim Harlow • 612-673-7768.