Hunter Water will invest more than $56 million on expanding the region’s largest wastewater treatment works.
This will also involve a more intensive monitoring program in preparation for another 50,000 residents by 2040.
Burwood Beach Wastewater Treatment Works processes the sewage of roughly 190,000 people, before discharging the treated effluent and biosolids to the ocean via a 1.5km, 22 metre deep outfall pipeline.
With the amount of sewage heading to Burwood expected to increase by 30 per cent by 2040, Hunter Water has completed a five-year consultation and research program to determine how the plant can function sustainably into the future.
The main considerations were the amount of nitrogen in the treated effluent and what to do with the biosolids produced at the plant. A community reference group was formed in 2010 and included representation from groups including Merewether National Surf Reserve Committee, Hunter Community Environment Centre and the Property Council of Australia.
This group met at key points throughout the project to help scope a way forward for the plant that balanced protecting environment and maintaining customer affordability.
Following a two-year marine environment study of the water quality and ecology around the plant’s ocean discharge point, four options for Burwood’s ‘Stage 3’ upgrade were tabled to the community:
- Current effluent nitrogen concentrations maintained and biosolids released to ocean
- Current effluent nitrogen concentrations maintained and biosolids reused on land
- Effluent nitrogen concentrations reduced and biosolids released to ocean
- Effluent nitrogen concentrations reduced and biosolids reused on land.
The EPA has accepted Hunter Water’s preferred option to maintain current nitrogen concentrations and continue releasing biosolids to ocean based on independent marine environment studies which showed that impacts were localised and subtle near the outfall.
The EPA has stipulated that Hunter Water conduct additional monitoring of the discharges to the ocean and undertake marine environment studies every five years.
Hunter Water will proceed with installing a $16 million ultraviolet disinfection system at the Burwood plant to kill bacteria and other pathogens in the treated effluent, in addition to the $40 plus million increasing the plant’s capacity.
Hunter Water will continue to work closely with the EPA on Burwood Beach Wastewater Treatment Works’ performance and review the need for a broader upgrade based on environmental monitoring results if necessary.
