Friday - August 1, 2014

Water Treatment Plant Construction Update

Preparing to backfill the 48” pipe

Loading fill and gravel to be compacted on the north side of the clearwell

This week, crews began backfilling the north side of the clearwell and installing the thickener mechanism in the gravity thickener tank. The lower walls were completed for the mechanical dewatering building, and work is now progressing on the suspended slabs. Crews continue to work on the ballasted flocculation walls and suspended slabs. The first concrete pour for the electrical building and chemical building slabs occurred on Thursday.

Over the next two weeks, work will resume on drilling auger cast piles for the finished water pump station (just north of the clearwell), liquid oxygen storage area (near the electrical building), and miscellaneous 30” – 42” piping. Concrete pours will continue for the ballasted flocculation, chemical building and electrical building. Water testing will begin on the solids storage tank. Refer to the current site plan for locations of each structure.

Truck traffic will continue with material deliveries and increase during concrete pouring. Pressure washing or sandblasting of the edges of newly poured concrete slabs will occur one or two days after a concrete pour. Neighbors close to the site on Mapleton Drive and Kenthorpe Way may experience an increase in noise during this work. 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 what activities are happening on site, potential impacts and location, please see the table below. We apologize for the inconvenience construction may cause and thank you for your patience as work progresses.

Neighborhood Construction Meetings – first and third Tuesday of the month

The next meeting will be held on August 5, at 7:30 a.m. in the downstairs restaurant area at Burgerville, 18350 Willamette Drive, West Linn. All meeting materials are posted online under “past meetings and events.”

WTP construction tours – held every two months

Tours are now held every two months on the fourth Thursday of the month at 10 a.m. The next tour will be held on August 28. Advance registration is required and space is limited. Please contact us to sign up for a tour!

For more information, please contact us.

Upcoming Activities*Purpose of WorkPotential ImpactsEstimated Duration

Week of August 4 - 9

1 Begin drilling auger cast piles for the finished water pump station, near the clearwell Auger cast piles will support the finished water pump station Noise, possible vibration as drill moves across the center of the site. 1 week
2 Continue forming shoring roof support for ballasted flocculation and mechanical dewatering building Provides covering for the structure and foundation support  No anticipated new noise, concrete pouring. Trucks entering/exiting with equipment, formwork. Some intermittent noise from water blasting or sandblasting concrete – south (Mapleton), center and northeast of site. 3 weeks
3 Begin water/leak testing the solids storage tank Cleans and tests new structure No anticipated new noise. Trucks entering/exiting and concrete poured – northeast of site. 3 weeks
4 Continue installing mechanical equipment for the gravity thickener tank The gravity thickener will thicken solids removed from the treated water  No anticipated new noise during installation of equipment. Trucks entering/exiting. Work occurring inside the tank – northeast of site.  2 weeks
5 Continue forming and pouring base slabs for electrical and chemical 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. Some intermittent noise from water blasting or sandblasting concrete –center and east of site. 3 weeks
6 Backfill area and install auger cast piles for Liquid Oxygen storage tank, near the electrical building  Refills excavated area  and auger cast piles support the structure Potential increase in vibration during backfilling – center of the site. Noise, as drill moves across site.  1 week
Week of August 11 - 16
1 Continue activities from 2 - 5 above
2 Begin drilling auger cast piles for miscellaneous 30” – 42” piping  Auger cast piles will support the piping Noise, possible vibration as drill moves across the center and east of the site. 2 weeks

*Please note, activity duration and schedules may change