Congestion Relief Coming Soon at Highway 13/5 Interchange in Burnsville

The end is finally in sight for one of the worst traffic headaches in Burnsville – but the nightmare is going to get worse before it gets better.

For years, motorists have endured long waits at the stoplight-regulated intersection of Highway 13 and County Road 5. Making a left turn from 13 onto 5, or from 5 onto 13, often demands patience even during light traffic. During morning and evening rush hours, the wait can sometimes seem interminable, and a study conducted in early 2000 determined that the intersection is the most congested and most accident-prone along Highway 13.

Discussions about fixing the intersection have been ongoing for more than a decade. But this spring, after years of soliciting impact statements and public comment, the Minnesota Department of Transportation (MnDOT) is ready to approve a final design for a new interchange at the intersection, with construction possibly beginning as early as fall 2012.

The final design, expected to be approved in April by MnDOT, calls for Highway 13 to be significantly lowered, with Highway 5 rising 20 feet above it – what’s known as a “grade-separated interchange.” Highway 5 will stay at its current elevation, but crews will have to dig down, sinking Highway 13 more than 20 feet, to achieve the necessary clearance between the two roads.

“If you want to change the two grades and have a grade instead of a stoplight, you have to be able to separate the elevations by 20 feet,” says Ryan Peterson, Burnsville’s interim public works director. “Since Highway 5 will stay at the same elevation, the minimum clearance for semitrailers and that sort of thing has to be about 20 feet.”

Burnsville city manager Craig Ebeling cautions that there is no final design yet, so discussions about exactly how the interchange will be configured are still premature.

"When engineers use the term 'grade-separated interchange,' they do it to differentiate it from an at-grade intersection," Ebeling says.

An at-grade intersection is one in which all four quadrants of the intersection are at the same elevation, Ebeling says. Safety and capacity can be improved by the addition of turn lanes and signal lights, but eventually it reaches a point where not much more can be done, given the volume of vehicles.

"So they separate the grades: One road gets higher and the other gets lower," Ebeling says. "And when you do that, you need to bring in other aspects so the movements can be facilitated, and you end up with ramps and that kind of thing.

"Will this look like a freeway interchange? Yes, kind of, but a special freeway interchange. It won't be exactly like a cloverleaf, but it will have a lot of the same features."

Peterson readily admits that the intersection is “not operating real well right now.” About 60,000 cars a day navigate that part of Highway 13, and 22,000 use Highway 5.

“This is the way it’s been since Burnsville was developed, as far as I know,” Peterson says. “Although at some point, Highway 13 was a two-lane road.”

Residents south of the Minnesota River rely heavily on Highway 13, which runs parallel to the southern bluffs of the river. It’s the primary means of access for cars to the Ports of Savage, and is a vital link for commuters in the growing southwestern suburbs as a connection to U.S. Highway 169 and Interstates 35W and 35E.

Highway 5 runs north and south through the northwestern part of Dakota County. It’s the only continuous road connecting Dakota County Highway 42 and Highway 13 and also provides significant traffic relief from I-35W.

Because the plan for the new interchange calls for Highway 13 to be sunk 20 feet into the ground, further traffic disruptions in the area during construction are inevitable, Peterson says.

“People are concerned right now about what will happen when it’s being built,” he says. “But there just won’t be access to Highway 5 from Highway 13. When you’re digging to that extent, there’s no way you’ll be able to cross over Highway 13.”

And, at this point, officials have no suggested alternate routes, according to Ebeling.

"That would be one of the most challenging parts of this project: how we handle the diversion of traffic," he says. "A lot needs to be worked out yet, and all we know that this is one of those construction projects that's going to be very challenging."

Peterson says the biggest year for the Highway 13/5 project will come in 2013, when construction will begin in earnest. Dakota County, which is in charge of administering the contract, with MnDOT responsible for designing the plan, expects to award a construction contract before December 2012.

“It’s going to take all of the 2013 construction season, and could get into some of the 2014 season,” he says.

In addition to the grade-separated interchange, the project will include a pedestrian walkway over Highway 13; construction of frontage roads along Highways 13 and 5 to provide local access to businesses; an interconnected sidewalk and trail system along the two highways and nearby Williams Drive; and a noise wall along the southeast frontage road.

The project’s total cost is $40 million. Of that amount, Burnsville will kick in $4 million and Dakota County $5.4 million. The balance will be paid for with $17.6 in state funds and $9.6 million in federal money.

The county maintains a web page with links and information on the project.