Friday - August 14, 2015

Next stage of excavation to begin at the WTP

Concrete pours for the filter slabs (background) and 54-inch pipe for the new filters ready to be encased (foreground)

Water Treatment Plant Construction Update

Information about onsite work over the next few weeks includes:

Truck traffic route change

Please note: starting next week and continuing through the end of major open-cut pipeline work on Mapleton Drive, the WTP contractor will be using Kenthorpe Way to enter and exit the site. Neighbors on Kenthorpe should expect an increase in truck traffic during this time.

New filters – northwest of site

Last week, the new 54-inch pipe that connects the new filters and ballasted flocculation was encased in concrete and, this week, plumbing was installed and the pipe encasement was backfilled to grade.

Work continues to form and pour the concrete slabs for the new filters. More than ten slabs have been poured to date. Soon, crews will begin forming and pouring concrete for the filter walls! As part of the concrete work, several trucks are arriving and departing the site. A few days after each pour, the edges of the newly-poured concrete slabs for the filters and the administration building will be waterblasted or sandblasted. Neighbors close to the site on Mapleton Drive and Kenthorpe Way may experience an increase in intermittent noise during this activity.

New administration building – north of site

Major structural work continues for the new administration building. Concrete is being poured for the grade beams, slabs and walls. Crews are also installing underground utilities (electrical conduit and plumbing). Soon, a large delivery of structural steel will arrive to the site, which will be used for the administration building and filters.

Washwater recovery basins excavation – northwest of site

Late next week, a large excavation will take place for the washwater recovery basins. These basins will be constructed next to the new filters, and will process the water and sediment that is removed from the filters. Afterwards, they are recycled back into the treatment process. 

The first phase of excavation should take about a week to complete. During this time, neighbors on Kenthorpe Way should expect an increase in truck traffic. Once the first half of the excavation is complete, crews will install “soldier piles” as part of a shoring system, using a vibratory method. This is expected to take about two days to complete, and will create some vibration and noise, depending on conditions and neighbor locations. Crews will then drill auger cast piles for the first half of the basins. Once this is done, this series of activities – excavation, soldier piles, auger cast pile drilling –will repeat for the second half of the basins. These activities are expected to take about a month to complete. During this work, neighbors located close to the site should expect an increase in vibration and noise.

Neighborhood construction meetings – next meeting Aug. 18 at 6 p.m.

The next neighborhood construction meeting will be held at Robinwood Station on Tuesday, Aug. 18 at 6 p.m. Please attend to stay up-to-date on construction progress in West Linn and ask the project team questions. 

Meeting schedule:
• The first Tuesday of the month at 7:30 a.m., at Burgerville, 18350 Willamette Drive, West Linn.
• The third Tuesday of the month at 6 p.m., at the Robinwood Station, 3706 Cedar Oak Drive, West Linn.

WTP construction tours

The next tour will be held on Sept. 24 at 10 a.m. Tours are held every two months on the fourth Thursday (pictured left). Advance registration is required and space is limited. Please contact us and indicate in the subject line you would like to attend the next tour, along with your contact information.

Work hours

Work hours are 7 a.m. to 7 p.m., Monday to Friday, and 9 a.m. to 5 p.m. on Saturdays.

Site plan and glossary

Please refer to the site plan for locations of each structure or our glossary of terms for construction and operation of the WTP.

For more information, please contact us or attend a neighborhood construction meeting.