MoDOT to begin major construction with lane and ramp closures at I-55 and Route Z starting June 19

JEFFERSON COUNTY- Drivers should be aware that beginning at 8:00 p.m. Friday, June 19, MoDOT will shift southbound I-55 traffic onto newly constructed median pavement north of Route Z to north of the Joachim Creek bridge.

Once SB I-55 traffic is shifted off the current bridge, Route Z will close under Interstate 55 and the southbound I-55 bridge over Route Z will be demolished.

Route Z will open up to one lane each direction no later than Monday, June 22 at 5:00 a.m. Once Route Z is reopened, the southbound I-55 exit ramp to Route Z will close for four months and the Route Z entrance ramp to southbound I-55 will close for five months.

Southbound I-55 will be reduced from three to two lanes north of Route Z for the remainder of the summer and fall, drivers should anticipate travel delays on southbound I-55.

Moving traffic onto the new median pavement and closing the ramps on the west side of I-55 allows for demolition and reconstruction of the southbound I-55 pavement and the southbound I-55 bridges over BNSF Railroad, Route Z, and Union Pacific Railroad.

All detours will be signed.

For additional information about current and upcoming detours and project status, please visit the I-55 Corridor Improvement project website at: Interstate 55 Corridor Upgrades in Jefferson | Missouri Department of Transportation (modot.org).

For up-to-date traffic and travel info, motorists can check MoDOT’s Traveler Information Map at http://traveler.modot.org/map/.

                                                                                ###