fall 2006
Dec. 13 - the overpass was struck by a vehicle exceeding the height restrictions on I-5. The overpass was struck by a vehicle exceeding the height restrictions on I-5. The overpass was reduced to one lane of alternating traffic after bridge inspections revealed damage to one of the bridge girders on the south end of the overpass.
winter 2006 - 2007
WSDOT Bridge Preservation office works on the damage report for this overpass and two other overpasses that were struck in Everett in late fall.
March 8 - Signal engineers improve the temporary signal by revising the signal timing to favor the busier direction of traffic depending on the time of day.
March 20 - Bridge engineers complete the damage report for the S. 178th Street overpass. The WSDOT Bridge Preservation office concludes that one of the 24 girders supporting the structure must be replaced.
spring 2007
WSDOT assigns a design office to get the appropriate permits, create traffic control plans for the repair work and determine how the repairs will be completed.
summer 2007
July 6 - WSDOT responds to neighbors requests by creating "do not block intersection" signs for King County crews to install at key intersections near the S. 178th Street overpass.
July 9 - After careful review and additional inspections two narrowed lanes are temporarily allowed to help ease traffic congestion across the overpass. Original fast-track plans to complete the design and construction this summer are pushed back due to scheduling conflicts with pre-planned summer construction projects.
August 9 - Preliminary design plans are submitted for review
fall 2007
Project contract advertised for bids to the private sector after approval of preliminary plans.
Submitted the order for the replacement girder to a local fabrication shop. Casting and curing this new piece for the bridge takes up to three months.
winter 2007 - 2008
Repairs on the overpass will not start until after the holiday season to accommodate holiday traffic to Southcenter mall.
February - 20, The overpass will be narrowed back to one lane of alternating traffic using a smart signal that detects traffic back-ups on either side of the overpass and automatically adjusts timing to minimize delays.
Feb. 23 - Feb. 24 - Saturday night at 11:30 p.m. until 7:30 a.m. Sunday morning crews will completely close all southbound lanes of I-5 between the I-405 interchange and S. 188th Street to tear out the damaged bridge girder. They will also completely close the S. 178th Street overpass between 10 p.m. and 8 a.m. the following morning.
March 1 - March 2 - Saturday night at 11:30 p.m. until 7:30 a.m. Sunday morning crews will completely close all southbound lanes of I-5 between the I-405 interchange and S. 178th Street to install a new bridge girder. They will also completely close the S. 178th Street overpass between 10 p.m. and 8 a.m. the following morning.
DRIVER ALERT: The remaining repairs will require 24 hour lane restrictions on the overpass until repairs are complete. These repairs include connecting the replaced girder to the rest of the overpass and re-pouring the south end of the bridge deck.
spring 2008
The project is scheduled to be complete and the overpass back to two lanes by May.