There is no good day to begin a closure of a major highway. The exact start date of the closure was dependent upon the contractor Seattle Tunnel Partners completing maintenance work on the tunneling machine. At the same time, we committed to providing the public with two weeks’ notice of the closure so drivers could hear about the closure and make plans.
Every day on this contract counts. Beginning the closure on a Friday is the result of our desire to provide the public with two weeks’ notice, while not losing any additional time on the project. Traffic volumes are typically lower on Fridays, and beginning on a Friday allows the closure to take full advantage of lower traffic volumes on weekends.
WSDOT recognizes that closing the viaduct will have a substantial effect upon local and regional traffic patterns. WSDOT is working with agency partners to keep people moving through a variety of measures (PDF), while asking drivers to make a plan and change traditional commuting patterns if possible to help keep traffic moving.