|February 2021 |
Greetings from the Portland Water Bureau.
Here’s an update on upcoming activities related to the Willamette River Crossing Project. This project will make sure we can deliver water to the west side of the river, even after an earthquake.
Exploration and analysis continue
In August, we finished work with our geotechnical probe, or geoprobe. The team is now using results from that probe to plan the next phase of the project. The geoprobe showed that we need more information to choose the best tunneling technology and route across the Willamette River. We will likely have to change the planned depth or drilling technologies to move the project forward.
Changing depth: If we go deeper, we can get below a layer of loose gravels that was a challenge during the geoprobe. To go deeper, we must collect more information about the soil there.
Changing technology: Another option is to use a different drilling technology that can move through the cobbles without going deeper. So while we are sampling deeper soils, we are also measuring information that will show us whether the new technology would work. Our contractor will use all of this information to design and construct the pipeline.
To collect the new information, our contractor is drilling and sampling in the Willamette River and nearby on the east and west sides of the river.
Soil sampling in the Willamette River Crews are working during times of year approved by the Oregon Department of Fish and Wildlife. We don’t expect any impacts to fish and wildlife or recreational uses from this work.
What’s happening next
Soil sampling on land Crews will collect soil samples then fill holes and restore each area to its previous condition. This will help us gather more information about soil deep underground. The contractor will use a sonic drill rig. This rig is about the size of a medium truck and is accompanied by a large support truck.
Time and duration: One to two days at each location, between the hours of 7 a.m. and 5 p.m. Monday to Friday.
Noise: During drilling, sound will be at approximately 90 decibels. This is like the sound of a passing diesel truck or lawnmower.
Sidewalks: Crews will lay plywood under the treads of the drilling equipment as it moves to and from the site, to protect the sidewalk. Apart from when crews are moving the drill rig, sidewalks will remain open.
Parking: The drill rig will be parked on or near the drilling location if the drilling takes longer than one shift.
Crews will collect soil samples in three locations near RiverPlace. They will first collect samples from the grassy area between the esplanade and the river. The contractor will build a sound wall at this location to reduce construction noise. Next, they will work in the grassy area between S Harbor Way and S Harbor Drive. Finally, they will collect a sample in the street near the traffic circle on S Montgomery. Streets and sidewalks next to soil sampling locations will remain open, with traffic cones for safety.
OMSI parking lot and SE Stephens Street Work to connect the new underground pipe to the existing water system on the east side depends on the results of the soil sampling described above. This work is scheduled to take place towards the end of 2021.
SE 7th Avenue, SE Harrison, and Stephens Streets Work to connect the new underground pipe to the existing water system on the east side depends on the results of the soil sampling described above. This work is scheduled to take place towards the end of 2021.
We want to hear from you If you know people who live in, work in, or travel through the area: Tell them about this newsletter. Invite us to your community or business group meeting for a project presentation. Share your comments and ask questions via email.
Water service emergencies: 503-823-4874