Drivers using the part of Interstate 35E that joins with Interstate 694 as the freeway passes through Little Canada and Vadnais Heights take note: You are being watched carefully by the Minnesota Department of Transportation.

There's no NSA-type spying going on here. The agency is just trying to see how traffic flows now that the metro area's newest MnPass lanes are up and running.

Earlier this month, MnDOT opened a new southbound express lane on I-35E between County Road 96 and Little Canada Road, passing through the 35E/694 commons. The new lane linked up with an existing MnPass lane that runs from Little Canada Road to Cayuga Street to create a continuous High Occupancy Toll (HOT) lane — as they are sometimes referred to in transportation agency parlance — from the northeast suburbs all the way to downtown St. Paul.

Things are different on the northbound side. An existing HOT lane runs from Cayuga Street up to Little Canada Road. The new MnPass lane begins at County Road E and runs out to County Road J. That leaves a 3-mile gap from Little Canada Road to County E where the far left lane ceases to be reserved for carpools, buses, motorcycles and paying drivers, and becomes a general purpose lane that can be used by all drivers during peak periods. The question is, will drivers understand this?

MnDOT used a $756,000 grant to analyze the impact of the nuisance not seen on the area's two other MnPass lanes on I-394 and I-35W or on many other HOT lanes across the country. Models concluded that the "innovative feature" on the northbound side would not be confusing or cause problems once motorists get used to it, said MnDOT's MnPass Policy and Planning Program Director Brad Larsen. But now it's time for the true test.

"We are trying two different innovative approaches to HOT lanes," Larsen said. Over the next two years, MnDOT will be eyeing drivers' movements "to see how it operates under real traffic conditions," he said. The feds want to know how it works out, too.

Back in the mid-2000s, MnDOT completed the "Unweave the Weave" project in which the agency reconstructed the eastern I-694/I-35E interchange and added lanes along the 694/35E commons to eliminate weaving and lane changes. The impact has been largely positive with the extra lane capacity leading to reduced congestion.

MnPass lanes are generally added in areas with high congestion. In this case, traffic in the commons generally flows freely, and thus an express lane is not needed on 35E between the two 694 interchanges. MnDOT, with the blessing of the Federal Highway Administration, saw the opportunity to test the impact of continuous and interrupted express lanes in a high capacity area.

Meanwhile plans are advancing for other MnPass lanes. The one furthest along is on I-35W from Hwy. 36 in Roseville to Lexington Avenue in Blaine. Preliminary designs are in the works and the project has been awarded $1.1 million in state funds and $800,000 in federal money.

Also underway is the Highway 169 Mobility Study, which is evaluating cost-effective options for Bus Rapid Transit and MnPass lanes on the clogged segment of Hwy. 169 from Shakopee to I-494 with the possibility of extending it as far north as I-394. There also is talk of adding MnPass on I-94 between downtown Minneapolis and St. Paul.

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