Detours begin as St. Louis County rebuilds Aurora's Highway 100 corridor

Detours began on Highway 100 in Aurora on Wednesday, June 10, sending everyday traffic onto Erie Street and Central Avenue and pushing large trucks to Highways 4, 111 and 100. The work cuts through CSAH 100 from Trunk Highway 135 to the railroad crossing, a stretch that reaches homes, downtown businesses and school trips in the center of town.

St. Louis County Public Works and the City of Aurora are carrying out the project as a multi-phase partnership, and county planners say the existing infrastructure has reached the end of its useful life. The main reconstruction zone covers about 1.08 miles from a point about 0.20 mile east of MNTH 135 to 1st Avenue North, with another 0.12-mile mill-and-overlay segment from 1st Avenue North to the railroad crossing. Project materials put the total cost at about $15 million.

The rebuild is more than a fresh layer of pavement. Plans call for a mini-roundabout at Main Street and 3rd Ave North, a raised median on 3rd Ave North between Erie Street and Hill Street with an opening for local businesses, RRFB pedestrian crossings at Hill Street and 1st Street, and a 6-foot sidewalk on the south side of 3rd Ave North between Erie Street and Hill Street. Those changes are aimed at slowing traffic, making crossings more visible and keeping access open along the corridor even as construction reshapes it.

The City of Aurora is also using the corridor work to replace water, sanitary sewer and storm sewer lines, realign 3rd Street between Mesabi East School and 3rd Avenue, and extend the Mesabi Trail as a non-motorized route from Pine Grove Park to downtown Aurora. A new 12-inch water transmission line is also planned between the water plant and the 1st Avenue/Main Street intersection, along with improvements at Pine Grove Park and the community center parking lot. The city received a $1 million Safe Routes to School grant in April 2025 for the Bradach Lumber and Mesabi East School intersection.

The project has been building toward this point for more than two years. St. Louis County held a public meeting on March 19, 2024, at the Aurora Community Center on the nearly two-mile corridor study, and county and city officials presented preliminary layout plans in November 2024 before moving into design for the 2026 construction season. Completion is listed for November 2027, giving Aurora a long construction season now in exchange for a rebuilt corridor meant to serve traffic, pedestrians and utilities for years to come.