Solo drivers who use the MnPass lanes to bypass congestion can expect to pay more for the express trip when ramps leading from northbound Interstate 35W into downtown Minneapolis close Friday night.

That might be money well spent for anyone who does not want to get caught in the epic traffic jams expected to form this week when the Minnesota Department of Transportation also slims down I-35 downtown.

Roadwork will squeeze 10 travel lanes down to five and push the 42,500 drivers who normally use the 5th Avenue, 11th Street and Grant Street exits each day to the one remaining access point: the winding ramp at 3rd Street and Washington Avenue behind U.S. Bank Stadium.

MnPass lanes are priced based on congestion levels, with drivers paying 25 cents to $8 depending on traffic volumes in the MnPass lanes. As traffic volumes increase in the lane, the fee to drive in the lane goes up. As traffic volumes decrease, the fee goes down. Volumes in the MnPass lanes are influenced by congestion levels in the general traffic lanes. As traffic builds in the general traffic lanes, more drivers will head to the MnPass lanes. For the next four months, until the downtown ramps reopen, drivers on I-35W can expect the MnPass fees to be on the top end of the scale.

"MnPass customers can expect to see higher-than-normal prices," said spokeswoman Bobbie Dahlke. "We expect more people to use them."

Rates charged on I-394 are also likely to spike as motorists from the southern suburbs hoping to avoid I-35W gridlock may opt to take the long way around and come into downtown from the west, she said.

With fewer general-purpose lanes available on 35W, commuters are being urged by MnDOT, downtown employers and city officials to take transit or carpool. Buses and carpools can use the MnPass lanes without having to pay.

MnPass lanes on northbound 35W will be in place from Burnsville north to 26th Street just south of downtown. The southbound MnPass lane will begin at 46th Street. The lanes will be in operation between 6 and 10 a.m. and from 3 to 7 p.m.

The goal behind the lanes marked with a diamond is to provide free-flowing traffic moving at 50 miles per hour or greater during rush hours. By limiting their use to qualified vehicles or paying customers, MnPass lanes help alleviate congestion, Dahlke said.

Drivers who are not MnPass subscribers may wonder why MnDOT doesn't open the lanes to all traffic, given the Chicago-like bottlenecks expected at all hours of the day and not just during weekday rush hours.

"MnPass lanes carry twice as many people as general-purpose lanes," she said. "Keeping the northbound MnPass lane operational through the construction zone will keep traffic moving through the entire corridor."

Motorists who get stuck wasting time and gas in traffic would probably scoff at that notion and might be tempted to cheat. But don't do it, Dahlke says.

The State Patrol has six troopers policing MnPass lanes, under a $2.6 million contract MnDOT signed with the patrol in 2016. If too many nonpaying drivers start using them, "we are prepared to add enforcement to the lane," she said.

Violators face fines up to $200. For that amount, you could buy a lot of trips in the MnPass lane even when they are priced at $8 a crack.

Dahlke said MnDOT will keep an eye on how the lane closures are affecting the traffic flow as drivers figure out how to navigate through the area or take other routes.

"If things bog down, we will make changes," she said.

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