Highway 100 and Exit 402


IM 0909(75)402 PCN 00WN and NH 0100(104)420 PCN 00X8


Construct Interchange, I-90 Exit 402_IM 0909(75)402, PCN 00WN and construct 6 lane urban section as part of Highway 100 from Rice Street to Exit 402_NH 0100(104)420, PCN 00X8


  • General
    • Contract Amount: $54.6 million
    • Work includes Grading, Structures, Curb and Gutter, Storm Sewer, PCC Pavement, Pavement Markings, Traffic Signals, Street Lighting, Sanitary Sewer, and Permanent Signing. The Highway 100 portion has a field work completion date of August 28, 2020 with the contractor having the option of placing the final surfacing in either 2019 or 2020. The I-90 Interchange Exit 402 has a substantial completion date of October 18, 2019. Work will not be allowed to begin prior to April 2, 2019, except for the westbound and eastbound on and off ramps.
  • IM 0909(75)402, PCN 00WN
    • The interchange at Exit 402 will require a new bridge. The new interchange will be reconstructed with a single traffic signal located at the center of the interchange (single-point) controlling all left turns.
  • NH 0100(104)420, PCN 00X8
    • The new Highway 100 will consist of 3 lanes in each direction, with a raised grass median and 2-foot wide colored concrete splash guard adjacent to the back of curb. The roadway will utilize a new alignment that will tie into Rice Street approximately 1700-feet east of the intersection of Timberline Avenue and Rice Street. The new roadway will require 3 structures, one crossing the Eastern Ellis Railroad as well as both a northbound and southbound structure spanning both the Big Sioux River and the Burlington Northern Santa Fe Railroad.
    • 60th Street North and Redwood Boulevard will both be realigned to better tie into the new Highway 100 alignment requiring a structure over Slip Up Creek. The existing structure on Timberline Avenue over the Big Sioux River will be removed. Timberline Avenue will have cul-de-sacs constructed on both the south and north sides of the Big Sioux River.
  • Traffic Affects During Construction
    • Timberline Avenue has been permanently closed between Rice Street and Interstate 90. Motorists are directed to use Interstate 229, Interstate 90, Rice Street, and Highway 11 until the new Highway 100 roadway and I-90 interchange is complete.
    • During construction of the I-90 Interchange, Exit 402 in 2019 the westbound off ramp will be required to stay open. Eastbound traffic will be directed to use Interstate 90, Rice Street, Cliff Avenue, Minnehaha County Road 130, and Highway 11 until the new interchange is complete and opened to traffic.

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