Photo Courtesy of WSDOT The 57.3-ft-dia "Bertha" is currently the world's largest tunneling machine. Now being shipped to Seattle in segments, she will begin excavation for the new state Route 99 this summer. Related Links: Here Comes Bertha Alaska Way Viaduct Proceeds Despite Mayor's Opposition When the 57.5-ft-dia earth-pressure-balance tunnel-boring-machine called Bertha reaches Seattle from Japan next month, it will make its debut at a 400-ft-long, 80-ft-wide and 80-ft-deep launch pit that crews have been toiling on for months. The 6,700-ton, 326-ft-long tunneler's arrival will be a key milestone in the $3.1-billion, 12-project program to replace the Alaskan Way Viaduct.The
The 2016 Summer Olympics boating and swimming events have put an international spotlight on what has been a long-running problem in Rio de Janeiro—untreated sewage and trash are clogging up major bays and waterways.