With its relatively low rainfall and long, dry summers, South Australia depends heavily on water flowing down the River Murray to meet its requirements.
In an average year, the River Murray supplies about 40% of the State’s urban water needs. In dry years, this can increase to as much as 90%.
In addition to being a major source of supply for Adelaide, the River Murray provides water for the domestic, industrial, livestock and irrigation requirements of the towns and farmlands both along its banks and further afield.
SA Water works closely with the Murray-Darling Basin Authority to ensure the long-term future of this vital river system.
Leading edge work is being carried out by SA Water in South Australia’s Riverland region with several large salt interception schemes already significantly reducing salinity levels in the River Murray.
Water from the River Murray is supplied around the state through five major pipelines.
The Mannum-Adelaide Pipeline was the first major pipeline built from the River Murray to serve the needs of Adelaide.
The use of the River Murray as a source of water for Adelaide was considered for many years but was not possible until barrages close to the river’s mouth were constructed to prevent saline water entering the lower reaches of the waterway.
The pipeline which extends from Mannum to a 136 megalitre terminal storage at Modbury is 60 kilometres long and swung into operation in March 1955. In 2005 we celebrated the 50th anniversary of the Mannum-Adelaide pipeline.
The pipeline supplies water to the metropolitan reticulation system through the Anstey Hill Water Filtration Plant (commissioned in 1980) as well as providing a direct supply for residents in the Torrens Valley and eastern foothills. The pipeline can also discharge water into the Millbrook, Kangaroo Creek, Hope Valley, Little Para, Warren and South Para reservoirs.
Murray Bridge-Onkaparinga Pipeline
By the early 1960s it became apparent that a second pipeline, in addition to the Mannum-Adelaide Pipeline would be needed to provide water supplies from the River Murray to Adelaide. The resulting Murray Bridge-Onkaparinga pipeline was constructed from 1968 to 1973.
The route chosen begins about 3 kilometres north of Murray Bridge and travels to the Onkaparinga River, west of Hahndorf.
The pipeline discharges River Murray water directly into the natural Onkaparinga River channel which carries it 10 kilometres downstream to Mount Bold Reservoir. Of the pipeline’s 48.6 kilometre length, 23 kilometres is below ground.
The pipeline also supplies water to the Summit Storage Water Treatment Plant.
The pipeline is designed to deliver 163,100 megalitres of water per year and cost $23 million at the time of construction.
Swan Reach-Stockwell Pipeline
The main purpose of the Swan Reach-Stockwell Pipeline was to supplement supplies to the Barossa Valley, Lower North and Yorke Peninsula areas, then served by the Warren Reservoir, and to supply townships and farming lands along its route.
The pipeline, which is 54 kilometres long and can pump 24,000 megalitres per year, was commissioned in 1969. A water treatment plant at Swan Reach treats all water pumped into the pipeline from the Murray.
The town of Whyalla was established early in the 1900s as a base for iron ore mining. In 1937 when consideration was given to establishing industries on a large scale in the region it was evident that continued growth would depend entirely on the provision of an assured water supply.
Construction of the first $5 million pipeline, which follows a route from Morgan through Hanson, Spalding, Helshaby and Port Augusta to Whyalla, commenced in 1940 and was completed in 1944.
The pipe diameter varies from 750 mm at Morgan to 525 mm at Whyalla and is predominantly above ground on concrete supports. The pipeline has a capacity of 9550 megalitres per year and is pumped through four pumping stations over a distance of 379 kilometres.
Extensions were made from the original pipeline from Port Augusta to Woomera, with branches serving Iron Knob, Jamestown, Peterborough and numerous other country towns and farming areas.
Rapid development in the Upper Spencer Gulf region following World War II indicated the need for more water than could be provided by the original pipeline. In 1962 construction began on a $30 million duplicate pipeline next to the first. The two pipelines lie side by side until near the Baroota Reservoir where the second line veers across Spencer Gulf via a 14 kilometre submarine pipe section to Whyalla.
The dual pipeline system is able to meet a demand of 66,000 megalitres a year. The Morgan Water Treatment Plant at the start of the pipelines treats all water pumped via this system.
Tailem Bend-Keith Pipeline
Thirteen towns and a large agricultural area in South Australia’s upper South East region are supplied with water via the Tailem Bend-Keith pipeline.
The trunk main, ranging in diameter from 750mm to 525mm, is 143 kilometres long and feeds more than 800 kilometres of branch mains covering an area of 6470 square kilometres.
Construction on the pipeline, which has a capacity of 11,500 megalitres per annum, began in 1964 and was completed in 1969. A water treatment plant at Tailem Bend treats all water pumped into this pipeline.