John Holland has been awarded the contract for the $34.5 million upgrade to Sydney Water’s Warriewood Sewage Treatment Plant (STP).


Warriewood STP serves an area of 25 square kilometres from Palm Beach to the north, Terrey Hills and Duffys Forest to the west and North Narrabeen to the south.  The local population is expected to grow by around 11,000, or 17 per cent, over the next two decades.


The capacity of the Warriewood STP needs to increase to reduce the likelihood of wet weather overflows to the environment and maintain the quality of Sydney Water services in the area over the coming decades.


Construction is due to commence in September 2011 and expected to be complete in 2012.


In addition to this new investment, Sydney Water has recently spent $14 million at the Warriewood plant to reduce odour impacts and also installed a cogeneration plant that utilises biogas, a by-product of the wastewater treatment process, to produce electricity.


The Warriewood STP upgrade is part of Sydney Water’s commitment to spending $560 million over four years to reduce the incidences of sewer overflows in its 23,000 kilometre sewer pipe network.