Friday - September 12, 2014

Water Treatment Plant Construction Update

Milestones reached at the site

A successful milestone was reached this week – it is one year since construction started at the plant. The nine acre site has been transformed to one that continues to have an operating 16 MGD plant, but that plant is now surrounded by the framework for the improved plant.

More than 60% (663) of the total auger cast piles have been installed on site to date. Over 7,000 cubic yards of concrete have been poured for seven new structures on the site. Concrete is complete for the clearwell and solids storage tank. The concrete is almost complete for the gravity thickener, mechanical dewatering and ballasted flocculation structures.

Temporary storage building

Over the next few weeks, crews will be installing a temporary storage building, on the southeast corner of the site. It will store large equipment arriving on site to be installed later. The building will be removed near the end of the project.

Primary power feed

Progress continues on the new primary power feed for the plant. Conduit has been placed between the new vaults between the northwest corner of the plant property on Kenthorpe Way to the plant entrance. Work is continuing on excavating and backfilling the trench through the center of the site to the electrical building. Neighbors close to the site on the western side may experience an increase in noise or potential vibration during this work.

Other construction activity

Work is continuing on installing 30” – 48” piping across the site. Deliveries are continuing to arrive with mechanical equipment for the ballasted flocculation and solids storage tank, which will be installed over the next month. Work will soon begin on installing the concrete blocks for the mechanical dewatering building and chemical building. Concrete pours will continue for the piping, finished water pump station and ballasted flocculation. Refer to the current site plan for locations of each structure.

Work hours are Monday to Friday from 7:00 a.m. to 7:00 p.m. and Saturdays, from 9:00 a.m. to 5:00 p.m. For more detail about construction, potential impacts and location, please see the table below.

Neighborhood Construction Meetings – first and third Tuesday of the month

The next meeting will be held on September 16, at 6 p.m. in the downstairs restaurant area at Burgerville, 18350 Willamette Drive, West Linn. Please come along to stay updated on construction progress in West Linn and ask questions of the project team. All meeting materials are posted online under “past meetings and events.”

For more information, please email lotwater@ci.oswego.or.us, call the hotline at 503-697-6502. 

Upcoming Activities*Purpose of WorkPotential ImpactsEstimated Duration

Week of September 15 - 30

1 Continue forming and pouring walls and installing piping for finished water pump station Supports foundation of the structure No anticipated new noise. Trucks entering/exiting, concrete pouring, crane operating to move forms and equipment – center of site, north of clearwell. 2 weeks
2 Continue installing mechanical equipment for the ballasted flocculation and solids storage tank, including pumps, tanks, piping and valves Provides mechanical operation of the filtration system No anticipated new noise. Trucks entering/exiting with equipment. Crane operating to install equipment – center of site. 3 weeks
3 Begin installing structural steel for electrical building Provide foundation and support for structures No anticipated new noise. Trucks entering/exiting with equipment. Concrete pouring, concrete trucks entering/exiting center of site. 2 weeks
4 Continue excavating, installing 30” – 48” piping and encasing pipe in concrete Auger cast piles and concrete encasements will support the piping Noise, possible vibration as excavator moves across the center and east of the site. Trucks entering/exiting, concrete pouring.  as excavator moves across the center and east of the site. Trucks entering/exiting, concrete pouring. 2 weeks
5 Install grout for floor of the gravity thickener tank The gravity thickener will thicken river sediments removed from the treated water No anticipated new noise, concrete pouring. Trucks entering/exiting – east of site. 2 weeks
6 Begin installing concrete blocks for mechanical dewatering structure and chemical building Provides walls for the structure No anticipated new noise. Trucks entering/exiting with equipment – northeast and center of site. 2 weeks
7 Continue excavating and installing preferred power feed for the plant Supplies power feed for the plant Noise, possible vibration as excavator digs and moves through center and west of site. 1 week
Week of September 22 - 27
1 Continue activities from 1 - 7 above

*Please note, activity duration and schedules may change