This view from the SKYFOX drone shows construction on the diverging diamond interchange at Interstate 41 and highways 15/OO (Northland Avenue) in Grand Chute Sept. 8, 2025. PC: Fox 11 Online
GRAND CHUTE, WI (WTAQ-WLUK) — Officials shared important information Thursday ahead of next week’s partial opening of the WIS 15/Northland Avenue diverging diamond interchange in Outagamie County.
“We’ve seen increased operations, better flows getting through Oneida Street in that area, and we’ve also seen roughly about a 40% decrease in the number of injury crashes to that location,” said Wisconsin Department of Transportation Traffic Engineer Mason Simmons, referencing the numbers for the current diverging diamond on Oneida Street in Appleton, which opened in 2018.
According to DOT reports, five years before the change, the intersection saw 114 total crashes, and six years after, they saw only 98. Those numbers showing crashes involving injuries went down 44%, while crashes involving property damage went down 22%.
Simmons said those numbers will extend to this new diverging diamond.
“It’s going to be a free-flow left turn, similar to your right turn lanes now,” he explained. “So with that, we see improved safety and we see improved operation getting along the corridor.”
Project manager for the I-41 project Bryan Learst said Northland was identified as having high left-turn traffic, and the new interchange will reduce the chance of crashes.
“With the DDI, it goes from 26 conflict points to 14, so it nearly reduces that chance of crashes, opportunities to crash, in half,” he said.
Learst added Northland’s opening marks a milestone in the work on the I-41 project.
“We’re nearing, kind of inching our way up north out of the Valley. But we do have a number of projects up on the north end now going as well. It’s pretty busy, but we’re moving north and in a couple years here, we’ll be primarily north of Wisconsin 47,” he said.
Northbound on-and off-ramps of the WIS 15/Northland Avenue interchange with I-41 will open late Monday. The southbound on-and off-ramps will remain closed until the fall.
The newly built interchange and bridge feature a diverging diamond design. In a diverging diamond, drivers cross over to the left side of the road. The idea is to make entrances and exits more efficient.
The new interchange is part of the yearslong project to expand I-41 to six lanes between De Pere and Grand Chute.
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