Drivers who maneuver through the stoplight-snarled intersection of Hwy. 169 and Interstate 494 will see congestion relief begin to take shape this spring.

But as the new stoplight-free interchange becomes reality, they best pay extra attention to the road.

Construction will be picking up once the weather warms, bringing temporary shoulder closures and lane shifts to allow for the road and bridge work.

The good news for those who travel Hwy. 169?

"They won't be shutting down lanes for a long duration or anything like that," said Bre Magee, a Minnesota Department of Transportation spokeswoman. "They want to keep two lanes in each direction flowing throughout the project."

Those lanes will shift, however.

In the vicinity of the project, which stretches from Anderson Lakes Parkway to Valley View Road, northbound 169 traffic will be shifted onto the southbound roadway, divided to allow for two lanes in each direction.

That will allow crews to reconstruct the northbound lanes. When they're done, they'll do the opposite and reconstruct the southbound lanes.

This summer's to-do list also includes construction of a frontage road network featuring six roundabouts, a ramp from westbound I-494 to southbound 169, and a new bridge at Washington Avenue just west of the main interchange.

There may be weekend or overnight closures of some lanes on I-494 or 169.

If all goes according to plan, the three sets of stoplights will be gone by November.

Until some of the other ramps are completed in 2012, drivers will need to navigate the frontage roads and roundabouts to get from one highway to another.

"There's going to be some learning curve," Michael Beer, MnDOT's project manager, told the Scott County Board at a recent meeting.

The entire $125 million construction project is expected to be completed by November 2012, to the relief of about 75,000 drivers who navigate Hwy. 169 each day.

"It's definitely going to improve the congestion that everyone experiences driving through the area," Beer said.

Scott County Board Member Jon Ulrich said the new interchange comes not a moment too soon.

"I don't know when we're going to see a big project like this again," he said, alluding to the Metropolitan Council's 2030 Transportation Policy Plan that focuses on smaller projects instead of large, expensive expansions.

The new interchange has been long desired, but the state lacked the money to upgrade the crossing.

The stoplights went in as a money-saving strategy when the four-lane Hwy. 169 opened in 1997. Almost immediately there were safety concerns and traffic snarls.

Hwy. 169 is particularly important as a commuting route for Scott County residents, and the county has long pushed for the new interchange, Ulrich said.

"It's a great thing for Scott County and all the partners," he said.

Katie Humphrey • 952-882-9056