The Seattle Times reports, “Nearly one-third of the Highway 99 tunnel’s upper road deck has taken shape, now that Highway 99 tunnel-boring machine Bertha has managed to consistently churn ahead since spring.” The report adds, “Workers at Seattle Tunnel Partners (STP) assembled the giant tube’s 1,000th concrete ring Tuesday morning [December 13], passing the 70 percent mark in the 1.7-mile route, while crews in the rear pour concrete for the roadway.”
