Construction Update 11: Key Milestones at Headworks and Contact Chamber

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Ground-level view of the Contact Chamber construction site, showing scaffolding surrounding a partially built structure made of CMU blocks. Stacks of unused CMU blocks and construction materials are visible on the ground, with an open field in the background.

Construction at the Headworks site is advancing with new walls and poured slabs, and electrical and plumbing installations underway. The Contact Chamber is taking shape with the first CMU blocks in place, marking a significant milestone. The Clarifier has passed water tests, and RLW is progressing with backfilling and shoring removal. Expansion continues on the Oxidation Ditch decking, and the anaerobic selector is preparing for a water test. Final touches are being applied to the aerobic digester and dewatering building in preparation for their upcoming water test. Overall, significant progress is being made across multiple projects.

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Headworks Progress: Walls Up, Slabs Poured

Construction progress at the Headworks site showing newly built walls, poured concrete slabs, and an excavated work area surrounded by safety barriers.

The Headworks project is progressing well, with additional walls constructed and several slabs poured. Electrical and plumbing installations are also underway. While a few sections remain to be completed, RLW is delivering excellent work.

Contact Chamber Progress: First CMU Blocks in Place

Aerial view of the Contact Chamber construction site, showing a rectangular structure outlined with CMU blocks and surrounded by scaffolding. Inside the structure, tarped materials are visible, with patches of snow and dirt around the site.

Ground-level view of the Contact Chamber construction site, showing scaffolding surrounding a partially built structure made of CMU blocks. Stacks of unused CMU blocks and construction materials are visible on the ground, with an open field in the background.

The Contact Chamber, which will soon house our UV building, is beginning to take shape with brickwork and the installation of CMU (Concrete Masonry Units). CMUs, precast rectangular blocks commonly used for walls, foundations, and other structures, are featured prominently here. We’ve captured both a top view and a side view of the progress. While these blocks will be utilized throughout the construction site, this marks their first application in this project.

Clarifier Passes Tests; RLW Begins Backfilling and Shoring Removal

Aerial view of a large, circular concrete tank under construction. The tank has a central opening with a small concrete structure in the middle. A ladder leans against the side of the tank. A small excavator is working on the side of the tank.

The Clarifier has successfully passed all water tests, and the scum pit formation is complete. RLW is now backfilling and removing the earth shoring simultaneously as they backfill and compact the soil.

Oxidation Ditch Decking Expanded; Water Test for Anaerobic Selector Planned

Aerial view of a large circular concrete structure under construction. The structure has multiple concentric rings and a central core.

The elevated decking for the Oxidation Ditch has been further expanded. The anaerobic selector (covered area) is being prepared for a water test, which is anticipated to take place next week.

Final Touches Underway on Aerobic Digester and Dewatering Building Ahead of Water Test

An aerial view of a construction site showing two large rectangular concrete tanks, partially complete. The walls of the tanks have been poured, and finishing touches are being added in preparation for water testing.

The aerobic digester and dewatering building has had all its walls poured, and RLW is now completing the finishing touches in preparation for an upcoming water test.

What's next?

Next week at the headworks, RLW will be backfilling the electrical room and beginning the underslab plumbing. The UV Building will continue with the construction of CMU walls. At the clarifier, water testing of the scum box will take place, followed by backfilling and the continued removal of earth shoring. In the Oxidation Ditch, RLW will proceed with installing elevated deck shoring and forms. Water testing will begin for the anaerobic tank, with backfilling scheduled once it passes. The Dewatering Building and Aerobic Digester will continue preparations for water testing next year. Weather permitting, vacuum testing of the gravity main and manholes will take place.

Thank you for reading this update. We hope you and your loved ones had a wonderful holiday!