Critical protection for Sydney's water supply
When the two pipelines that deliver Sydney's water supply from the Warragamba Dam needed urgent high-tech coatings, Dulux Protective Coatings delivered on the challenge.
The pipelines (2.1 and 3 metres in diameter), which travel approximately 65 kilometres from the dam in Sydney's west, form an integral component of Sydney's water needs. The Warragamba storage lake is four times the size of Sydney Harbour and stores around 80 per cent of Sydney's water. The project to upgrade a 2.8 kilometre section of the pipelines started in 2021 and created a unique and challenging set of restoration conditions.
With their extensive experience in specifying and supplying protective coatings that meet some of Australia's most unique requirements, Dulux Protective Coatings was selected earlier this year to supply the coatings for client Eptec, who was awarded the maintenance project on behalf of Water NSW.
Preparation reveals pipeline’s condition
Managing the project for Dulux Protective Coatings was NSW technical sales representative Jack Jaber.
"Before work could commence, the exterior of each pipeline had to be thoroughly pressure cleaned to determine the existing coating condition, which had been affected by dirt and mould," Jack explains. "Following the thorough clean, there was only a short period of time when the coatings could be applied, as temperature variations and other environmental factors impacted the delivery window."
A system was specified featuring three of Dulux Protective Coatings' most durable and long-lasting products to complete the job:
- Spot repairs of primer Zincanode 402 @ 75 microns
- Spot repairs of intermediate coat Durebild STE @ 150 microns
- Second and third coats of Industrial Aluminium @ 25 microns
A first class anti-corrosion solution
Once the true condition of the pipelines was visible, it became clear that approximately 2.8 kilometres required robust restoration. The team started with the spot repairs using Zincanode 402 a two-pack epoxy zinc rich primer offering exceptional cathodic corrosion resistance for the pipeline's harsh corrosive environment.
Durebild STE was selected for spot repairs to act as the all-important intermediate coat. Specifically designed to withstand tough Australian conditions, it provides years of protection against fresh and salt-water immersion.
To finish, two full coats of Industrial Aluminium were applied to provide maximum protection against corrosion in varied temperatures.
"Industrial Aluminium is a durable oleo resinous enamel coating containing high levels of aluminium flake," explains Jack. "As a topcoat, its finish provides a bright metallic sheen. Its highly effective heat reflection is ideal for the above ground pipelines that experience extreme temperature variations, including up to 200°C, protecting the water inside from contaminants."
Strong relationships and product supply ensure durability for years to come
The total treatment area for the two pipelines came in at approximately 20,000 square metres.
Although the project is still under way, Jack says the first set of results look sensational.
"These critical pipelines that deliver drinking water to Sydney have gone from looking aged to brand new," Jack says. "The challenges for this project were based on the tight application window due to environmental conditions, but working closely with our brilliant applicators at Eptec has led to a streamlined approach."
"Weekly usage reports ensured we could manage supply closely and provide products in full and on time."
The project, which will extend the life of the pipelines for many years to come, is successfully being undertaken without any interruption to Sydney's water supply.
The experts at Dulux Protective Coatings can help you protect critical infrastructure for the long term. Contact us for technical coatings advice, tailored to your project.