Thiess is part of a successful consortium that will deliver an enhancement and upgrade of Perth's three main metropolitan wastewater treatment plants.

The program of works will be delivered under an alliance agreement with the Water Corporation and a design and construction consortium of Thiess, Black & Veatch, and Sinclair Knight Merz. The program of works involves the upgrade of Beenyup, Woodman Point and Subiaco wastewater treatment plants.

By the end of the program, the capacity of the Beenyup and Subiaco wastewater treatment plants will be increased by at least 15 million litres a day at each plant. At the Woodman Point Wastewater Treatment Plant, the solids treatment capacity will also increase to align with the overall hydraulic capacity of the plant of 160 million litres a day.