The $40million Harcourt Rural Modernisation Project, currently being undertaken by Coliban Water, will replace the Victorian region’s century-old irrigation infrastructure with a modern and efficient pressurised water supply. The extensive works involve the installation of 65km of pressurised pipeline, two pump stations and a balancing storage tank.
The small rural town of Harcourt is located in the Central Highlands region of Victoria, located approximately 121km from Melbourne. It is the foremost apple growing region in the state and home to developing wine and cider industries.
For the last 100 years, the town and surrounding regions have been supplied with water for irrigation via a system of open concrete and earthen gravity channels. However, as a secure and reliable water supply is vital in order to underpin the agricultural growth in the region, the need to replace this ageing infrastructure with a more modern and efficient system was identified.
The Harcourt Rural Modernisation Project will provide rural customers in Harcourt with year-round access to water through a pressurised piped system. The new system is expected to save around 3,000ML of water per year. These savings include an estimated 950ML of water loss and a further 2,000ML from water licences that rural customers sold to Coliban Water in 2013.
Coliban Water formed the Harcourt Water Services Committee in November 2008, composed of Harcourt rural customers who provided advice and guidance on modernisation.
In 2012 the business case to modernise the irrigation system was approved by the Victorian Government and works began at the site in March 2014.
The backbone of the new system is a 19km, 500mm ductile iron (DICL) pipeline, which allows for a maximum flow rate of approximately 23ML a day.
The reticulation pipeline is 44km and made of either polyethylene or DICL. The diameter of the reticulation pipeline varies from 63-225mm, depending on the required flow.
There are two pump stations at Barkers Creek and Faraday. The Barkers Creek pump station includes four Omega 200-670B pumps and Faraday includes three Flygt CP3240 submersible pumps.
A 2ML concrete balancing tank has been constructed in North Harcourt. The tank is approximately 24m in diameter.
Contractors and works
The contract for the supply of pipes and fittings was awarded to Pentair in 2013, including various fittings, valves, ductile iron pipe and fittings to be used to construct the backbone of the new modernised rural pipeline system. All pipes and fittings have been supplied to the site.
The tender for the supply of pumps was awarded in two parts; one for each new pump station site. Xylem was contracted for the Faraday site and KSB for the Barkers Creek site. The total cost for both pump supply contracts was around $600,000. These contracts involved the supply of the pumps and motor sets needed for the new pump stations.
The contract for the construction of the balancing tank at Harcourt-Sutton Grange Road Harcourt North was awarded to A1 Quality Concrete Tanks; and the contract to construct the pipeline and pump stations was awarded to Redline Group.
Building the pipeline
The majority of the pipeline has been laid using traditional trenching methods.
Thrust boring and directional drilling were used for the backbone pipeline, and directional drilling for the reticulation pipeline.
Trenchless techniques were used for sections that passed under roads, a cattle pen and a dam. There were also sections with significant native vegetation and areas of cultural heritage that could not be trenched.
The original construction timeframe for completion was September 2014. Works on the project were temporarily suspended in October 2014 to resolve matters between Coliban Water and the pipeline construction contractor. Construction of backbone pipe recommenced in February 2015.
As of 25 March 2015, around 95 per cent of the backbone pipeline and 55 per cent of the reticulation pipework has been installed. Construction of pump stations at Faraday and Barkers Creek is around 30 per cent complete.