WSDOT owns a couple of the movable barrier systems and has used them primarily on interstate freeway HOV widening projects over the past several years. They work well in adding an additional level of … [Read more...] about Temporary Movable (“Zipper”) Barrier systems in work zones
Washington
Temporary rumble strips
WSDOT has been interested over the past few years in temporary rumble strips, and has tried a few different types without much luck. The most recent product evaluated has been a temporary rumble … [Read more...] about Temporary rumble strips
Permit requirements to install/erect temporary traffic control warning signs and other temporary traffic control devices along roadways
Washington DOT requires a permit and an approved traffic control plan to work or set up traffic control in state right of way. … [Read more...] about Permit requirements to install/erect temporary traffic control warning signs and other temporary traffic control devices along roadways
Work zone impact thresholds
WSDOT does not use performance specifications. Time of day restrictions or night work is specified based on hourly traffic volumes. Generally WSDOT uses analysis programs such as QUEWZ98 to calculate … [Read more...] about Work zone impact thresholds
Flagger training and certification requirements
From Washington State Department of Transportation Standard Specifications for Road, Bridge, and Municipal Construction: "1-10.3(1)A Flaggers Flaggers shall be posted where shown on traffic control … [Read more...] about Flagger training and certification requirements
Vehicle warning lights
The requirements are included in WSDOT Vehicle and Equipment Warning Light Systems Manual. … [Read more...] about Vehicle warning lights