Desalination & Reuse Handbook - Flipbook - Page 20
IDA
WATER SECURITY
HANDBOOK
HUNTER, NEW SOUTH WALES
A reliance on the water-intensive mining and agricultural industries in the water-scarce Hunter Valley has long driven
Hunter Water to take a proactive approach to water security. With drought driving reservoir levels across southeastern
Australia towards 60% – the trigger level for activating desalination plants – Hunter Water (HW) has avoided applying
extraordinary water restrictions, with the region’s water storage remaining close to 80%.
Water-saving measures initiated following the Millennium Drought that hit Australia in 2001–2011 are largely responsible
for this resilience. In 2011, consumer surveys reported 90% of respondents had installed dual flush toilets and 80% had
fitted water-efficient shower heads after HW rebate and exchange programmes. Where the average water volume supplied
per property by HW was 184 m3 in 2009–2010, the average for the period 2010–2017 was 171.5 m3/yr. This is slightly above
the 170 m3/yr average for the same period among Australian utilities serving more than 100,000 connections, with Hunter
Water’s 2016–2017 average of 172 m3/yr placing the utility 5th in that group.
In 2014, HW issued the Lower Hunter Water Plan, detailing the region’s commitment to developing its water security
infrastructure in seven key areas: surface water; groundwater; efficiency; demand management; recycled water; rain and
stormwater use; and temporary desalination. The Plan also introduced tiered “Water Wise Rules” for consumer water use.
Water Wise Rules are permanent measures to manage demand, ranging from basic rules that are always in effect to more
severe measures that kick in as storage levels fall, requiring high-volume users to develop and implement water efficiency
plans. In total, these responsible usage programmes account for around 1,200 m3/d of water savings.
Alongside demand management, network efficiency and water recycling are key to Hunter Water’s approach to water
security. Programmes to detect leaks and manage network pressure are projected to save 1.7 million m3/yr by 2034, with
savings from national and regional efficiency programmes expected to save 4.5 million m3/yr over the same period (a
combined average of around 17,000 m3/d). Meanwhile, water recycling reduces potable water use in industry: the 2014
Kooragang Industrial Water Scheme provides 9,000 m3/d of treated wastewater for industrial use, resulting in a 5%
reduction of overall potable water consumption. The scheme was sold to Water Utilities Australia in 2017.
Hunter Water has managed to avoid reliance on unconventional water resources to secure its potable water supplies.
Although the utility is overwhelmingly reliant on surface water, modifications to conveyance infrastructure during the
2000s enabled interregional ‘water banking’ between Hunter and Central Coast, creating 35,000 m3/d of transfer capacity
for resource sharing in times of shortage and the ability to better manage localised stormwater.
A proposed 15,000 m3/d desalination plant remains an emergency measure, with detailed design to be carried out only if
storage capacity drops below 65%, with construction starting at 35%. If levels were then to rise above 50%, work on the site
would cease.
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