Warriewood Wastewater Treatment Plant

Odour management

Sydney Water has recently completed an odour treatment upgrade to reduce the odour impact of the Warriewood Wastewater Treatment Plant (WWTP) and facilitate the further residential development of land within the existing buffer zone. This project provided covering of odour sources from the wastewater treatment process, collection and treatment of contaminated air via a ventilation system and discharge of odours through a ventilation stack.

Renewable energy

Sydney Water has recently implemented a Renewable Energy Generation Program, as part of its commitment to being carbon neutral for energy and electricity use by 2020.

As part of the program, Sydney Water installed a cogeneration plant at the WWTP, which utilises biogas, a product of the wastewater treatment process, to generate electricity. The cogeneration plant, along with 10 other renewable energy plants, will generate around 22% of Sydney Water's energy.

Upgrade project

Sydney Water is upgrading the Warriewood Wastewater Treatment Plant to:

• improve the operating reliability of the plant
• reduce the frequency of wet weather overflows from the plant
• continue to meet the Environmental Protection Licence requirements
• provide sufficient capacity to service growth in the catchment to 2031.

The upgrade work will include:

• amplifying the capacity of the existing plant components, which are currently operating at or nearing capacity, to accommodate future demands
• utilising amplification of the clarifier capacity to achieve overflow abatement objectives
• upgrading equipment to achieve reliable operation
• investing in plant enhancements to improve efficiency.

The key benefits of this important work are:

• the plant will be able to service growth up to 2031
• compliance with the Wet Weather Overflow Pollution Reduction Program will be achieved
• current plant reliability issues will be addressed
• the plant will be able to operate automatically with minimal intervention
• bio-solids stability will be improved enabling them to be reused more effectively
• bio-solids transportation will be reduced.

John Holland Pty Ltd was awarded the $23.4 million contract for the upgrade of the Warriewood Plant. Construction started in July 2011 and is expected to be finished in late 2012. Work hours will be 7am to 6pm Monday to Friday and 8am to 1pm on Saturdays. Residents will be notified if night work is required.

Environmental assessment

Sydney Water prepared a Review of Environmental Factors (REF) for the Warriewood plant upgrade, to assess the potential environmental impacts of the proposed work and outline mitigation measures.

The REF was placed on public display in July 2010. Following the review of submissions in a Decisions Report, Sydney Water decided to proceed with the project.

Community

Sydney Water will continue to update the community and stakeholders on project progress.