It has taken years for swift MnPass lanes to reach east metro freeways. But soon, they'll be coming in waves.

State officials are fanning out across the northeast suburbs to prepare officials for the arrival of the express lanes in phases on Interstate 35E over the next year or so, and potentially Interstate 35W after that.

They're also explaining new rules that eliminate the need for monthly lease payments for those who sign up for the tags placed in vehicles, and are promoting the arrival soon of technology allowing drivers to use those tags on trips to Chicago or elsewhere in the U.S.

Some details on phasing:

• Express lanes on I-35E between Little Canada Road and Cayuga St. will open as soon as late November.

• Lanes from there north to County Road J/County Road 96 open in the fall of 2016.

• A section of 35W between Hwy. 36 and Lexington Ave., costing up to $180 million, could be added in 2019-2020.

The lanes cost money to motorists driving alone during congested periods: from a quarter to $8, depending on traffic conditions.

As the east metro comes online, the state Department of Transportation is offering a new feature: Rather than pay $1.50 in monthly lease fees, motorists can buy a tag for less than $15 that can be moved from car to car or switched off when carrying a passenger. Motorists also can get a free one, knowing, though, that it is always in "fee mode," and they'll be charged later based on use.

Transit vehicles, motorcycles and vehicles carrying two or more people use the lanes for free.

MnPass will be in effect weekdays from 6-10 a.m. heading south and 3-7 p.m. going north. That means that "90 percent of the time, they're free to everyone," said MnPass spokeswoman Bobbie Dahlke.

David Peterson