Background

About the Darling Anabranch

The Anabranch Pipeline system operates 3 pump stations to maintain a consistent supply of water. River pump stations are located on the Murray River at Fort Courage, and on the Darling River at Polia and are essentially identical systems with three submersible river pumps lifting water to a tank and network pumps which convert filtered water to network pressure. In addition to the river pumps, there is a solar booster pump station halfway along the system at Wyndham which boosts pressure to the top end of the system during the day.

Water is most commonly pumped from Fort Courage, with the Darling River pumps (at Polia) being less frequently utilised due to the lower water levels in the Darling. Prior to the installation of the booster station, there were often difficulties maintaining pressure at the highest end of the system, a problem overcome by the installation of the booster pump. Water is boosted to the top of the system during the day during the highest demand, and the river pumps can maintain network pressure overnight when there is typically less demand.

Outlets along the system distribute water to the landholders who have tanks, restrictors, meters, and pressure reduction systems at each property. Calculations for infrastructure were based on total acreage and carrying capacity, with each system designed to be able to be filled from empty within two days. In some instances, water is delivered directly via a pressure reduction valve, but the majority pump into the tanks and then distribute to the paddock from there. Some troughs and paddock tanks were allocated through the establishment phase in order to build resilience across the system.

There are 83 outlets across the system. One irrigation license 501ML is held by Anabranch Water- Allocated to 8 landholders.

History of the Darling Anabranch

1997

In 1997 the Great Anabranch of the Darling River Water Trust (the Trust) successfully applied for Natural Heritage Trust (NHT) funds to develop a new management plan for the Darling Anabranch system.

1998

The Darling Anabranch Management Plan (DAMP) Steering Committee was established in 1998, with representatives from local landholders, government agencies, and industry. Following consideration of a number of options, it was agreed that a pipelined water supply with environmental flows was the best option for all stakeholders.

DAMP proposed:

Construction of a pipeline to provide stock and domestic supplies, as well as some irrigation water, to landholders along the Darling Anabranch. The pipeline would include connection to landholders existing pipeline systems, provision of additional fencing where the Darling Anabranch pool levels had previously acted as a fence, and provision of water infrastructure (including on farm storage) to paddocks which had lost their Darling Anabranch water access as a result of fencing.
Securing Water Access Licences totalling 3,000ML from both the Murray and the Darling Rivers.
An entitlement of water made available for an environmental flow for the Darling Anabranch stream.
Removal of a number of in-stream structures, and provision of alternative access points.
Funding to cover the annual cost of operation, maintenance and eventual replacement of the pipeline and associated infrastructure.

2003

In 2003, Water EcoScience were engaged by DAMP to provide a “desk top” study into the alternatives and options for providing stock and non-potable domestic water to the 43 properties that exist along the Darling Anabranch. The study concluded that a system comprising of river pumping stations located at both the Murray and Darling rivers and connection by approximately 315 kilometres of main and spur pipelines would be the most viable and sustainable option for provision of water to the properties. In addition to the river pumping stations, booster pumping stations would be placed at suitable locations along the pipeline.

2004

In 2004 DNR engaged Earth Tech Engineering to provide an Environmental Impact Statement (EIS) for the proposed Darling Anabranch Stock and Domestic Pipeline. Later in 2004, the NSW Department of Commerce were engaged to provide a design and construct specification for the pipeline scheme and to manage preconstruction works for the pipeline.

Optimatics Pty Ltd was engaged by Department of Commerce to undertake Genetic Algorithm Optimisation of the proposed Darling Anabranch Stock and Domestic Pipeline to provide a cost effective solution to compare solutions for a number of design scenarios.

2005

In 2005 funding of $54 Million under “The Living Murray” was secured to construct the Darling Anabranch Pipeline.

“The Living Murray” package is a $700 million investment by New South Wales, Victoria, South Australia, the Australian Capital Territory, Queensland and the Commonwealth to improve the health of the Murray River by recovering water for environmental purposes. The eventual aim is to provide an extra 500GL of water to six significant Murray River environmental (icon) sites. A priority is to recover water through water use efficiencies.

DNR is the project proponent for the Darling Anabranch Pipeline and Environmental Flows project (The Project). The Department of Commerce is contracted by DNR to provide project management and pipeline construction management services.

2006

Mitchell Australasia Pty Ltd was awarded the construction contract in February 2006, with construction works commencing in May 2006.

The Project provides non-potable water to landholders through a pipeline system (The Pipeline) which consists of low lift pumping stations, high life pumping stations, filtration systems, balance tanks, and wastewater systems at the Murray River and Darling River. The above components are connected by 218.6 km of network delivery pipeline. Along the delivery pipeline are 97.3 km of spur lines with off takes for 72 consumers. The Pipeline will also have flow metering and telemetry monitoring.

An adaptively managed environmental flow and removal of instream structures are also part of The Project. An Environmental Flows Technical Committee has been convened by the Lower Murray Darling Catchment Management Authority (LMDCMA) to provide advice on the environmental flow requirements of the Darling Anabranch. This Committee will also provide advice on the design and establishment of a program of monitoring, evaluation, and adaptive management. The Darling Anabranch has two landholder representatives on this Committee.

In August 2006 the decision was made that flows in the Darling River were insufficient to provide water to The Pipeline. The Murray River pump station, with a booster pump, was commissioned as part of the construction contract. This configuration will provide water to landholders until flows in the Darling River are sufficient to commission the Darling River pump station.

The pump station on the Murray River was commissioned on 18 December 2006, operating at 25% capacity.

2007

In February 2007, a booster pump was commissioned which allows The Pipeline to operate at 40% capacity.

DNR has proposed that Anabranch Water should take over the operation and maintenance of The Pipeline for an interim period from 1 March 2007 until 29 February 2008 under contract to DNR. The interim period will allow both The Board and DNR to:

• gain an understanding of the operational requirements of The Pipeline,
• collect data to refine the sinking fund requirement, and
• refine the proposed future management of The Pipeline.

2008

On 1 March 2008, it is intended that a Deed of Separation will be signed, the sinking fund handed to Anabranch Water and ownership and operation of The Pipeline will then be the responsibility of Anabranch Water.

2013

Fort Courage

In 2013 the Anabranch Board investigated the option of installing solar panels to power the Fort Courage River & Supply pumps. The Board determined that solar would be an excellent investment in reducing electricity costs.

Through analysis it was determined that at Fort Courage a 15kw system would be installed at the River pumps and a 30kw system at the System pumps.

Research and quotes were obtained, and the Board was careful to choose the right solar panels and inverters for their situation.

The site was prepared, fenced and panels installed. The panels are located to receive full sunlight and face north. The site is accessible for maintenance and cleaning.

The power production, use and export to the grid is monitored on a monthly basis.

Following an increase in electricity prices and a decrease in solar panels costs an additional 30kw was installed at the Fort Courage system pumps in October 2015.

The system provides a return of approximately $30,000/annum in saved electricity costs.

2015

Wyndham Booster Pump

In 2015 the diesel generator and pump installed at the Wyndham booster pump site, was replaced with a 15kw solar plant and motor/ pump. This system boosts the pressure in the top end of the Anabranch supply pipeline and ensure all landholders receive their allocated flow rate per day.

2016

Anabranch Water Trust & Anabranch Water

In 2016 the Anabranch Water Trust, a private water trust known established under the Water Act 1912, was wound up. The Trust’s roles and responsibilities were assumed by Anabranch Water. This included the responsibility for management of environmental flows and flood events in the Great Darling Anabranch. In order to perform these roles Anabranch Water has the responsibility to control, use, operate and maintain selected structures along the Great Darling Anabranch. Due to the poor state of the 183 Dam, WAMC (Water Administration Ministerial Corporation) has assumed responsibility for this asset. WAMC is responsible for the ongoing control, use, maintenance of this structure. WAMC will, if necessary, repair/replace, Regulator 183 at its own cost and keep the structure at an acceptable standard.