1 STATE WATER STRATEGY Office of Water Strategy Jos Mensink
Director Office of Water Strategy August 2005
www.ourwaterfuture.com.au
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2 Runoff to Hills dams in 2001 only 30% of 25 year average -
about 40 GL compared to average of 180 GL. Inflow in 2002 only
slightly better with about 90 GL. Combined inflow for those two
years is the worst on record. Water becomes one of top three
community issues and Government established the Water Taskforce. 19
Water forums held in 2002 (9 metro area, 10 regional) and
Parliament House Symposium in October 2002 to build framework for
the State Water Strategy. State Water Strategy released February
2003. 2003 runoff was about 150 GL. S hort History of State Water
Supplies
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3 Rainfall 14% less 21% less 2001, 36% less Streamflow
Percentage changes are relative to 1911-1974 period 52% less 64%
less 2001, 88% less
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4 Informed adaptation to climate change Decrease Last quarter
century winter rain as % of previous 75 years A drier and warmer
climate for the SW
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5 Water Resources Portfolio Water Resources Cabinet Sub
Committee Chair: Premier State Water Council Chair: D Hatt - Office
of Water Strategy - Senior representatives from Government Agencies
- Water Service Providers - Ministerial Advisors New Water
Resources Entity by 1/9/2005 Water Utilities - Water Corporation -
Busselton Water - AQWEST Bunbury Minister for Water Resources
Premier (Option) Minister Assisting in Water Resources Hon J
Kobelke Department of the Premier and Cabinet Policy Division
Office of Water Strategy Strategic Policy and Planning J Mensink
(Director) Senior Steering Group (DPC, WC, DoE, DTF)
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6 The Office of Water Strategy provides high level advice to
the Government in relation to water strategy and facilitation and
coordinates Government activity including new water source
developoment, demand management and water reuse. It also provides
support to the Premiers Water Foundation and other Committees
involved in the implementation of the State Water Strategy. The
Governments preferred option for longer-term administrative support
for the Water Resources Portfolio should be substantially
progressed by September 2005. The State Water Council consists of
nominated senior representatives from government agencies,
ministerial advisers and water utilities. The Council acts as a
forum on water related matters and provides advice to the Water
Resources Cabinet Sub-Committee. Roles
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7 Gnangara Mound
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8 Identified potential GDEs not previously considered based on
depth to groundwater mapping of Gnangara Mound. Gnangara >400
wetlands 33 Bush Forever Sites supporting areas of phreatophytic
terrestrial vegetation 6 mound springs 4 caves near shore marine
systems. Identified ecological values of new GDEs Outlined changes
in ecological condition (where assessed)
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9 Gnangara Mound
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10 Climate 2 Decline predictions @ 2015 28 year Monthly Median
8 year Monthly Median
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12 Future abstraction for public water supply Demand: assume
the 155 KL/person demand target is met by 2012 New sources: 45
GL/yr Perth Seawater Desalination Plant by late 2006 17 GL/yr water
trade by 2008/09 45 GL/yr South West Yarragadee by late 2009
Drought security: ~0.5% chance of a total ban on sprinklers
Groundwater abstraction: Gnangara groundwater is critical a
variable allocation between 105 and 165 GL/yr depending upon
storage in dams will secure the IWSS
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13 Gnangara Mound Aquifers AquiferThickness (m) Storage (GL)
Salinity (mg/L) Water Corp Abstractio n (GL/yr) Superficial20 to
70>20,000