SEATTLE (Reuters) - An expressway tunnel central to Seattle's $3.1 billion roadway overhaul will not open to traffic until August 2017, extending by some nine months a delay-plagued project to replace a waterfront highway, Washington state officials said.
The latest setback pushes the project well past the November 2016 time frame identified by crews replacing the Alaskan Way Viaduct with a tunnel near downtown, among other road improvements.
"This is very difficult work and certain construction activities have and will continue to take longer than anticipated," the Washington state Department of Transportation said in a statement on Monday.
The tunnel-digging project halted when a drilling machine broke down a year ago. Workers have been trying to dig a 120-foot pit to reach and repair the drill, nearly 60 feet in diameter.
That effort was halted this month after officials said some 30 buildings in an historic downtown neighborhood would be inspected for damage because they sit in a wider area encompassing the viaduct that has sunk about an inch since October.
On Monday, the state said survey crews found "some minor cosmetic damage in a handful of buildings, but no structural damage has been discovered."
Crews aimed to resume work on tunnel-digging by late March 2015, with the goal of opening the underground expressway to traffic in late 2016, the state said.
The schedule Seattle Tunnel Partners submitted to Washington state in October, however, showed tunneling would resume in late April 2015, and the project would be open to traffic in August 2017, the state said.
(Reporting by Eric M. Johnson in Seattle; Editing by Susan Heavey)