Minnesota Department of Transportation

511 Travel Info

Hwy 169, Hwy 22 Minnesota River Flood Mitigation

Mankato, Saint Peter

Orange barrels on a highway

Future work

Hwy 22 South of Saint Peter (2015)

  • Raise the grade and reconstruct from Hwy 169 to the existing Minnesota River Bridge
  • Construct a 120’ span bridge to handle additional water flow during high water events
  • Detour required

Hwy 169 Mankato to Saint Peter (2016)

  • Project benefits

    • Flood mitigation – U.S. 169 flooded 4 of the past 5 years; this project raises the road above 100 yr. flood
    • Safety – Median barrier added to prevent head-on traffic crashes
    • Smoother road – pavements are deteriorated
    • EDA (Economic Development Agency) grant for $9.8 million applied to project


    Schedule and Scope

    • 2016 – Hwy 169  Mankato to Saint Peter
      • Includes raising the grade and reconstruction in four areas, for a total of 3 miles
        • Hiniker Mill
        • 7-mile creek
        • Old River Road
        • South of St. Peter near State Hospital
      • Includes 6 miles of preservation/resurfacing
      • Includes median barrier

    Key Issues

    • Narrow terrain between bluff and MN River
    • Highway originally constructed in the early 1960’s, the Minnesota River high-water elevation was assumed at 751 and the roads were constructed accordingly
    • Unsuitable soils in reconstruction areas
    • Impacts to 6(f) environmental properties of Seven Mile Creek and Riverside Park
    • Management of traffic (13,700 ADT) during construction and access to businesses during construction

    Detour considerations

    • Construction would require two years w/o detour and 2-lane, 2-way traffic comes with safety issues
    • Highway 22 and Nicollet County Road 13/Hwy 99 being considered for detour routes
      • Hwy 22 Avg. Daily Traffic – 8,000 to 10,000
      • CR 13 Avg. Daily Traffic – 830
    • Safety improvements to detour routes under development (at intersections and access revisions)
    • Highway 14 to I-35 option for traffic headed to Twin Cities
    • Narrow terrain between bluff and MN River requires construction on both northbound and southbound
    • Public meeting on project and detour coming in Jan. 2015