Washington State Department of Transportation has started drilling soil samples for two major projects, the US$500 SR 520 Bridge over Lake Washington and the US$2 billion Alaskan Way Viaduct replacement. Crews on the bridge project will work at 15 drilling locations in the lake, each of which will take about two days to cover. The existing structure is one of the world’s oldest floating bridges. Six new drilling locations are being checked for the viaduct, following the earlier completion of investigations in the south and central project areas.