Highway Closure and Detour Between Mankato and St. Peter Starts April 15

The Minnesota Department of Transportation (MnDOT) is scheduled to resume a major detour on Highway 22 between Mankato and St. Peter on Wednesday, April 15, 2026. This action marks the start of the second and final year of a multi-year construction project aimed at reconstructing the roadway and improving regional infrastructure.

The closure will affect the stretch of highway from south of Blue Earth County Road 57 in Mankato to just south of the Minnesota River Bridge in St. Peter. Through traffic will be detoured to Highways 14 and 169 during the construction period.

Project Scope and Infrastructure Improvements

The 2025-2026 project focuses on the reconstruction of Highway 22 to improve traffic flow, reduce delays, and enhance safety. The scope of work includes the addition of new turn lanes and passing lanes throughout the project area.

Beyond the roadway surface, the project involves several critical infrastructure upgrades:

• Repairing and replacing bridges, including specific work on the Rabbit Road bridge north of Kasota, which is expected to begin later in the spring of 2026.
• Improving lighting at intersections.
• Installing snow fences.
• Designing and grading for a future walking and biking trail intended to connect Mankato and St. Peter, separated from traffic lanes.

A roundabout at Hill Street, also known as Le Sueur County Road 21 near Kasota, was completed in 2025. This roundabout will remain open to local traffic while the broader detour is in place.

Timeline and Traffic Impacts

Construction is expected to continue until fall 2026. MnDOT noted that schedules remain subject to change based on weather conditions and other unforeseeable circumstances.

The project was phased to manage traffic impacts over three years. In 2024, the project resulted in minor impacts to Highway 22 traffic. In 2025, work focused on the northern and southern ends of the highway, with traffic detoured to Highway 169, though the detour was removed during the winter months.

For the final phase in 2026, the primary focus is the reconstruction of the middle section of the highway. While through traffic is detoured, access for local businesses and residents will be maintained.

Public Engagement and Updates

To inform the community about the final phase of construction, MnDOT hosted a construction open house on Tuesday, April 7, 2026, from 3:30 to 5:30 p.m. At the MnDOT office located at 2151 Bassett Drive in Mankato.

The department intends to provide ongoing transparency regarding the project’s progress by sharing periodic drone video updates on the official project website.

The project aims to achieve several long-term benefits for the region, including a reduction in crashes at intersections and along Highway 22, as well as providing a smoother ride through improved pavement quality.