Australian Water Management Review Vol. 1 2014 | Page 146

Cowan West Hoxton
Wastewater Schemes
and

T

he Priority Sewerage Program (PSP) is
a NSW Government initiative that aims
to provide improved wastewater services
to unsewered urban communities in
environmentally sensitive areas. The
Cowan and West Hoxton Wastewater schemes
are a part of Sydney Water’s $170 million
Priority Sewerage Program to deliver improved
wastewater services to six targeted village areas.
The $20 million Cowan and $9 million West Hoxton
Wastewater schemes have recently been delivered by
an alliance between Sydney Water, MWH Australia
Pty Ltd, John Holland Group Pty Ltd, United Group
Infrastructure Ltd and RPS Australia Asia Pacific.
Most properties within both areas are residential and
use on-site wastewater management systems. The
most common types are:
• septic tank with pump-out
• septic tank with on-site soil absorption
• aeration treatment with on-site irrigation.
Some of these systems leak or overflow. Leaks from
on-site systems impact the air and water quality
in the area. Surface water monitoring carried out
prior to construction showed that the quality of
water in the area may pose some health risks to the
community.
Other issues with on-site systems can include:
• inability to cope with increases in household
numbers due to visitors
• poor performance during wet weather
• odours
• mosquitoes and other insects.
The main objectives of the new schemes were to
provide a wastewater service that:
• reduced risks to public health
• improved public amenity
• protected the surrounding environment
• provided capacity for limited identified growth in
both areas
Benefits of connecting to the new schemes include:
• the opportunity to remove existing on-site
wastewater systems and use a more reliable and

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