State getting ready for SR 543 upgrade
The Washington State Department of Transportation (DOT) has begun drilling test holes at the corner of D Street and the truck route (Highway 543) in preparation for a project that will lower and widen the highway, set for next year. The contractor, Condon-Johnson & Associates of Tukwila, has been operating a large hydraulic drill and a crane at the site for the past two weeks.
The holes are being drilled, according to Philip Larsen, state project inspector working out of the DOT’s Bellingham office, to see what kind of engineering will be required to create retaining walls on either side of the lowered highway. “We’re drilling six holes from 25 to 72 feet deep and three to four feet wide, will fill them with concrete and then dig a trench along one side to see if they deflect under a side load. That will help us come up with engineering specification when we put the project out for bids.”
Larsen said that the ridge is mostly made out of clay, but that they have occasionally hit some large granite boulders. To give an idea of the size of the project, which includes an overpass for D Street, Larsen pointed out that all the drilling equipment and the test holes are sitting in the highway right-of-way. “It goes all the way to the fence that’s east of the truck route,” Larsen said.