In November 2006, a chunk of U.S. 2 east of Index slipped down the mountainside more than 7 feet. The state Department of Transportation hammered dozens of 40-foot-long spikes into the slope and built a 130-foot-long wall to hold the road in place until a permanent fix could be designed. The state is now designing that permanent fix.
State Transportation Department spokeswoman Erin Bogenschutz answers questions about the project.
Q: What caused the sinking?
A:The record rains we had last November caused the ground underneath the road to become saturated. Then there was a landslide that took the road with it.
Q: Why was a temporary fix necessary?
A:We had to make sure the road was stable while we designed a permanent fix.
Q: How are those spikes holding up? A:
A:They’re holding up great. We haven’t had any problems with them. Obviously the road is still there. The wall is doing its job. We haven’t seen any additional movement of the hillside.
Q: Are there any restrictions on the road at this point? A:
A:We have a reduced speed limit of 35 mph in the slide zone. Once the permanent repairs are in place, we will restore the speed limit to 55 mph.
Q: What is the permanent fix going to be?
A:It’s still in design, but what we’re looking at is a “soldier pile wall.” It’s a retaining wall made with steel beams and wood planks. It’ll probably be about 200 feet long and 20 feet tall.
Q: What will tie the new wall to the slope?
A:The steel beams will be driven into the base of the slope. We will also drive more spikes from the wall into the hillside. We are still deciding how long they have to be, but they will likely be over 100 feet long.
Q: Are the spikes from the temporary wall going to be taken out?
A:The original wall and the spikes are going to stay there. We’re going to build the new wall over the old wall. They’re going to work together. They will reinforce each other.
Q: When does this new wall get built?
A:We are looking at going into construction in August and finishing — weather dependent — in October.
Q: How much will this endeavor cost?
A:The temporary repair was $1.3 million. The permanent fix will be $2.9 million.
Reporter Lukas Velush: 425-339-3449 or email@example.com.