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Gerringong Gerroa Sewerage Scheme – Meeting the needs of growing communities


Veolia, on behalf of Sydney Water, designed and built a sewerage scheme, a first of its kind by the private sector within the Gerringong region.

Gerringong Gerroa Sewerage Scheme

THE CHALLENGE

Sydney Water Corporation is a state government-owned statutory corporation that provides potable drinking water, wastewater and stormwater services to Greater Sydney, the Illawarra and the Blue Mountains regions in New South Wales.

The regional townships of Gerringong and Gerroa on the New South Wales south coast required a reticulated sewerage system that would allow for reuse.
 

THE SOLUTION

Veolia, on behalf of Sydney Water, designed and built a sewerage scheme, a first of its kind by the private sector within the Gerringong region.

The advanced wastewater plant treats sewage from the surrounding population using tertiary filtration, ozone, biologically activated carbon, microfiltration and ultra-violet disinfection.

The scheme is designed to reuse 80 per cent or more of the treated effluent for irrigation at a local dairy farm. There are also occasional discharges into adjacent sand dunes and into a nearby natural wetland in extreme wet weather conditions.

The scheme’s 2.2ML/d capacity sewage treatment plant is located on Baileys Island, south of Gerroa and adjacent to the Crooked River.

Veolia’s water management solution consisted of:

  • Advanced tertiary treatment process involving ozonation, biological activated carbon (BAC), microfiltration and UV disinfection
  • Effluent reuse
  • Advanced monitoring to ensure the treated water quality is consistent within contractual specifications.


COMPREHENSIVE COLLECTION AND TREATMENT PROCESS TO ENSURE ADHERENCE TO GOVERNMENT STANDARDS
Sewage collected from individual households drains to sewage pumping stations at low points in the sewer catchments and is then pumped through pressure pipes to the next catchment downstream and ultimately to the sewage treatment plant.

The collection system comprises 12 sewage pumping stations and 50 km of sewer gravity and pressure mains. Due to the environmentally sensitive area and the desire to minimise sewage overflows, the sewerage system provides storage for peak wet weather flows, with pumping stations holding the equivalent of three hours of peak dry weather flow in addition to two hours of upstream flow.
 

THE RESULT

  • Advanced tertiary treatment process involving ozonation, biological activated carbon (BAC), microfiltration and UV disinfection.
  • Effluent reuse.
  • Advanced monitoring to ensure the treated water quality is consistent within contractual specifications.
  • All concentration, toxicity and load limits met since commencing operations.
     

KEY FIGURES

  • 2.2ML/d capacity sewage treatment plant
  • Services a population of 8,000