ABOUT BAROSSA INFRASTRUCTURE LTD
“To provide a high quality water supply in the Barossa which, when applied in environmentally and viticulturally appropriate quantities, sustains crop yield and quality through dry periods at a cost that is lower than other quality water sources.”
Barossa Infrastructure Ltd (BIL) is an unlisted public company with capacity to supply 10,000 Megalitres per annum of supplementary irrigation water to viticulture in the Barossa Valley. The initial capacity was 7,000 Megalitres per annum. SA Water provides the connection to the Warren Reservoir, supplemented with water supplied via the Mannum Adelaide Pipeline and Warren Transfer Main, from the River Murray.
BIL is required to have River Murray Water Allocations for the water supplied by SA Water. This water comes from Water Access Entitlements, either purchased or in the form of long term leases, and annual Water Allocations purchased on the market.
It is the objective of the company to achieve the ownership of about two thirds of average customer demand in the form of High Security Water Access Entitlements (or equivalent). Currently, BIL holds about one quarter of projected demand.
The company has also been active in seeking alternative water sources in the interests of sustainability of viticulture in the Barossa. During 2010, in cooperation with The Barossa Council, reuse of treated effluent from Nuriootpa Community Water Management Scheme (CWMS) was commissioned. The water is supplied to a small number of customers along Gomersal Road Tanunda. This represents about 4% of annual use.
BIL’s customers are shareholders in proportion to their contracted volume of Premium Water (which can be used all year round). The Scheme cost in the year 2000 was approximately $30 million, funded approximately 1/3 by shares and 2/3 by a long term bank loan. The final loan payment of $1.37 million will be paid in July 2016. In addition to usage charges customers pay an annual infrastructure levy. No Government funding financed the Scheme although considerable assistance was provided in negotiation of the necessary permits.
From the BIL water year commencing 1 Oct 2015, the Scheme has been expanded to 9,000 Megalitres. This has been achieved by SA Water increasing the capacity of the transfer main to the Warren Reservoir and by changing their operational strategy for the South Para Reservoir.
KEY STRUCTURAL ELEMENTS
• 189 kilometres of buried pipeline ranging in size from the trunk main of up to 960 millimetres in diameter down to distribution mains of 150 millimetres in diameter
• Distribution area covering 450 square kilometres Click here for Map
• Four booster pumping stations, the largest with a pumping capacity of 630 kilowatts
• 31 pressure reducing valves on the lateral mains which protect both the mains and customers’ equipment
• Supply of approximately 430 separate connections to 300
• customers’ properties; each connection being provided with a meter and flow control valve to maximise efficiency of water use
• Supply of 260 ML per annum of Class B reclaimed wastewater from Nuriootpa CWMS to 14 customers on Gomersal Road Tanunda
• Provision of electronic flowmeters fitted with web-enabled communication modules to all customers, partially funded by the Commonwealth “Water for the Future” program and the ‘South Australian River Murray Sustainability Irrigation Infrastructure Improvement Program’, enabling automation of meter reading, soil moisture monitoring and enhanced customer service
Typical Customer Connection
THE NEED FOR SUPPLEMENTARY IRRIGATION
For approximately 30 years, supplementary irrigation water had been supplied during the drier summer months from underground sources and via run-off from surface catchments, to ensure consistent quality grapes are produced. Existing water supplies were becoming inadequate to sustain market position in the wine industry.
Supplementary irrigation is required for three main reasons:
- Use of inferior quality (saline) water, either groundwater or surface water
- Annual variation in rainfall and temperatures
- Catchment water harvesting at sustainable levels
- Negative correlation between yield and quality with increasing salinity
- Mining of deep aquifer water for irrigation leading to the importation of salt to surface soils, and surface drainage
BIL Offtake at Fromm Square
BIL has environmental approval to transfer 9,000 Megalitres per annum from the River Murray and has applied to increase this to 10,000 Megalitres per annum. The sustainability of vineyards depends on good environmental practice.
A detailed assessment was made that addressed:
• The potential for the use of BIL water to result in a rise in regional water tables
• The effects on the salt budget and the potential for increases in the salt load entering surface drainage as base flow
• The potential for the creation of perched water tables with adverse effects on plant growth, and for migration off-site
• The effects of any changes in salinity and chlorine residuals on ecosystems and the implication of inter-basin transfer of water.
As a condition of the approval for the use of CWMS water from Nuriootpa, BIL arranges an independent audit of the safety and environmental effects of the Scheme.
Security of River Murray Water Rights is an important issue for BIL. Water trading when there is a shortage has been a method of supplying water in drought years.
To date there has been no detrimental impact on the environment. BIL commissioned a report on the shallow water table every two or three years to study the impact of the imported water from the River Murray. The average salinity of the water supplied to customers is 300 parts per million, well inside the best-practice limit of 800 parts per million.
Inside Airfield Pumping Station
WORKPLACE HEALTH AND SAFETY
Above ground operating cabinets for the Pressure Reducing Valve (PRV) chambers have been installed to enable improved workplace health and safety by eliminating the necessity for combined space entry and the requirement for traffic control and by permitting pressure monitoring of the PRV’s via live data over the internet.
PRV 12 One of many in the system
Barossa Infrastructure Ltd is examining ways in which the effect of climate change and reduced water availability from the River Murray may be managed. It has become obvious over the past few years that the impact of climate change is drier springs and hotter summers resulting in an increased demand for water over short but critical periods.
Ongoing initiatives include:
• Keeping abreast of aquifer storage and reuse options to explore the potential of either providing the opportunity for future sales of Off Peak water or to provide storage against years of low water availability
• Discussions with local Councils re storm water reuse
• Considering options for incorporating winery waste or further effluent water into the system
• Discussing options for future inclusion of Bolivar Waste Water