Australian Water Management Review Vol. 1 2014 | Page 123

Normally the second installation would be
conducted from Young Street; however, the location
of the access chamber in Young Street and the
amount of roadway available for working made this
an unsuitable option. Close discussions with the
Roads and Maritime Services (RMS) and Sydney
Buses resulted in Phillip Street being chosen as the
preferred option for the inversion location. The work
was completed successfully with no incidents.
Novelty of technology
There are two unique parts to this lining installation.
Firstly, Kembla Watertech utilised a one-of-a-kind
wet out conveyor system; and secondly, the size of
the liner made it a remarkable installation.
Kembla Watertech invested over $200,000 in a new
CIPP wet out conveyor system that could handle the
sheer size of this liner. The wet out conveyor system
took six months to purpose build and takes up most of
a large industrial warehouse in Sydney’s southwest.
This installation was the largest diameter and
thickest CIPP lining inversion ever conducted in
Australia and one of the biggest worldwide, coming
in at 1,550 mm diameter (to fit the 1,830 x 1,220
mm pipe with a wall thickness of 35 mm). It took
significant physical labour to manoeuvre and install
inside the pipe.
Environmental and community benefits
The Heritage-listed Bennelong stormwater channel
was built in 1857. It is the first oviform sewer to be
built and one of five original combined stormwater/
sewer systems built in Sydney at the time. These
channels improved public health, hygiene and living
standards immensely for the people of Sydney.

The site was less than 100 m from Circular Quay,
Sydney’s popular tourist hub, and close to historic
districts. Circular Quay hosts the ferry terminals and
a main CBD train station. Surrounding the site were
high rise business and residential towers, and the
five star Intercontinental Hotel.
Due to the amount of vehicles required for the job,
Kembla Watertech utilised the bus layover lane
in Phillip Street as part of the work zone. Buses
had access around the zone, and the layover
was relocated to a different street. This required
significant consultation with Sydney Buses
management staff.
Traffic impacts
Stakeholder discussions were held early on with
the surrounding businesses and residents to ensure
everyone was informed of the impacts from the
work. Phillip Street experiences a high volume of
traffic, so traffic control was staffed 24 hours a day
and managed closely so that traffic flowed smoothly.
Occupational health and safety benefits
The benefits to the wellbeing and safety of the
workers and general public that cross paths with
trenchless projects are numerous.
The reduction of open excavations using a lining
project as opposed to an open cut technique so
close to a public location was a huge benefit
to community safety. Risk assessments and
consultation with all affected authorities ensured
adjacent infrastructure was protected along with the
wellbeing of the workers.

Constructing the purpose built wet out bed, which
was predominantly there due to the sheer size of the
liner, had a separate benefit of reducing the physical
labour required during the wet out process, thereby
protecting the safety of the workers.
Project outcomes
Rehabilitating the Heritage-listed Bennelong
stormwater channel was a major achievement.
Kembla Watertech was honoured to be part of
the rehabilitation of such an important historical
asset for the community. The officers conducting
environmental and heritage assessments, and the
workers who were able to enter the access chambers
were struck with a sense of awe at the engineering and
construction methods used over 150 years before.
Notwithstanding the heritage significance of this
asset, the skill required to install a liner of this
size is a major feat for Kembla Watertech. To have
inverted the largest oviform liner in the southern
hemisphere requires intensive planning, skill and
physical labour of great proportion, and it was done
successfully and to plan.
This was a major accomplishment for Kembla
Watertech, particularly considering the in-depth
stakeholder and environmental planning that was
required for this project, and its location in the
heart of Sydney.

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