MnDOT gears up for 'can of worms' redo
State and local transportation officials are conducting business as if the next mega infrastructure project on the horizon in Northeastern Minnesota is already here.
Four concepts to rebuild the "can of worms" interchange in the Lincoln Park neighborhood of Duluth will be the topic of small-group meetings with local businesses and organizations next week.
A public meeting will follow sometime in early November, said Roberta Dwyer, a Duluth-based project manager with the Minnesota Department of Transportation. All of the concepts being considered — called options B, C, I and O — would feature fewer bridges and more on-the-ground roadway for Interstate 35, which is now mostly elevated through Lincoln Park.
A clearer funding picture is also expected soon for a project estimated to cost $205 million.
"We're looking under every couch cushion," state Transportation Commissioner Charlie Zelle said, briefly addressing the topic with the News Tribune during the opening of Minnesota Highway 210 through Jay Cooke State Park earlier this week.
Rebuilding the stretch of I-35 through the interchange would come in phases across multiple construction seasons, said Dwyer.
As it gears up to pay to rebuild what's formally known as the Twin Ports Interchange, MnDOT is finalizing two federal grant applications for more than $60 million, due in the next few weeks. Meanwhile, state grants already are being processed, with MnDOT officials expected to know outcomes "hopefully very soon," Dwyer said. One of the state grants is aimed at economic development dollars and the other at freight improvements.
"This is certainly an area for freight, particularly now with the intermodal terminal," Dwyer said, referring to the recent Duluth Cargo Connect agreement with Canadian National Railway to transit container cargoes through the port. "Also, with all of the other businesses through that area, this is certainly a critical freight route."
The can of worms interchange — where I-35 meets Interstate 535 and U.S. Highway 53 — is a series of curving ramps and elevated freeway that is characterized by cumbersome merges and yields for drivers. In the five years through 2015, there were about 500 crashes at and in the vicinity of the interchange, making it one of the most hazardous zones on all of I-35 between Minnesota and Texas.
Officials said a Twin Ports Interchange project would make the stretch of I-35 and all of its offshoots safer, reduce bottlenecking that occurs on the busiest days, and allow large trucks hauling big loads to use the highways.
Structurally, the interchange has been showing its age for many years already, having gone up in the late 1960s. Overweight trucking allowances haven't been made since 1982, when a beam crack forced a temporary shutdown of a portion of the interchange, Dwyer said.
With as many as 27 bridges under "fracture critical" or other compromised statuses, the interchange has had to be diligently scrutinized and maintained. Trucks with overweight loads are forced to avoid the interchange and use city streets in order to leave town. Also, tractor-trailer combinations were shorter back in the day, Dwyer said, and some of today's legal-weight but longer rigs must avoid tighter portions of the interchange.
Draft concepts shared with the News Tribune this week make it clear that MnDOT is considering a variety of new ways to reimagine how the interstate engages with the major arteries of I-535 and Highway 53 south over the Blatnik Bridge to Superior, and Highway 53 north onto Piedmont Avenue. Meetings with stakeholders next week, Dwyer said, figure to help winnow down the concepts.
In all of the concepts, most of the elevated segments of the I-35 roadway — some just a few feet high — will be brought to the ground.
"In the late 1960s there were not the geotechnical methods we have now," Dwyer said. "The soils along the corridor are poor — a lot of it is old lakebed, with some of it filled long before the interstate came into existence. The water table into the can of worms is about a foot down. We have different geotechnical methods now that would allow us to put it on ground and that way have a lot fewer of the lower bridges."
Pilings on those bridges have deteriorated over time, and more rapidly than anticipated. A piling rusted to holes found in late 2013 closed a portion of the interchange for a week for repairs. Poor stormwater drainage throughout the interchange creates flooding on adjacent streets and finds stormwater running down the piers, contributing to their degradation, Dwyer said. Stormwater runoff would be improved in the new project.
Also in the concepts, the project would introduce an industrial-sized roundabout designed to be used by commercial traffic on Garfield Avenue, and extend Courtland Street to connect with Railroad Street, creating a new artery from the west into downtown and Canal Park — one outfitted with a corresponding pedestrian and bicycle path.
Courtland Street would be the start of the work, Dwyer explained, followed by the I-35 roadway and bridges, the Highway 53 (Piedmont Avenue) bridges from Superior Street to West Third Street, and finishing up with the I-535 bridges at Garfield Avenue near the port.
It all adds up to a project that has made it to the front of the line since first gaining momentum in spring 2016.
Surveying, noise and environmental studies and underground utilities location are all taking place throughout the I-35 corridor between the 27th Avenue West and Mesaba Avenue/Superior Street exits, and the I-535 corridor from I-35 to Garfield Avenue at the foot of the Blatnik Bridge.
"We will be taking some initial soil borings in the next few weeks," Dwyer said. "We want all the information we need to enter into the project."