Through the glass darkly- uncertainty, climate chaos & Water policy reform challenges. Presenter: Jason Alexandra MDBA November 2009. Overview. Background Context and Challenges A Brief History of water resources policy Water reform in context Climate change Conclusions.
Through the glass darkly- uncertainty, climate chaos & Water policy reform challenges
Presenter: Jason Alexandra
MDBA November 2009
"Charles Darwin …. Visited Sydney in 1836. After an uncomfortable tramp over the Blue Mountains in a heat wave, he concluded that Australia could never become another America - its soil was too poor, its rains too unpredictable. Instead it must depend on becoming "the centre of commerce for the southern hemisphere and perhaps on her future manufactories.“
As quoted in McCalman, The Age, 10 August 2002.
Despite these warnings “Successive Governments sponsored closer settlement and intensive irrigation development, with dreams of taming the rivers, greening the desert, and making land productive, running deep in the national psyche (Lines 1994) notwithstanding, punishing droughts and misconceptions about the severity of the natural constraints to settlement and production (Taylor 1940). Generations of school children have been taught of love for “a land of drought and flooding rain” (McKellar 1987). Reflecting Australia’s climate pulsing through its wetter and drier phases. Our natural ecosystems have evolved superb adaptations to the inherent climatic variation (Cullen 1998).”
Successive Australian governments have attempted to “tame the rivers and made the deserts productive”.
The majority of the MDB is flat, semi arid and developed for agriculture and pastoralism.
The “wet” parts, like the main rivers, floodplains and wetlands are critical habitats – with their pulse of drought and flood.
Major legacy issues
Very high nutrient and suspended sediment loads
Largely unmodified in all aspects
Australian water era and habitat
Irrigation and habitat
18,000,000 and habitat
Government funded development of dams
Major periods of water diversions
(note Murray average inflows approx 9,000,000 ml)
Surge in cereal and oil prices Commodity prices (US$/ton)
An engineered system and habitatThe MDBC has an Engineering Heritage
The Murray – an “exotic river” and habitat
Maximum reduction in yield: and habitat
Vic 2003 fires: Reductions of up to 1237 GL/y in 20 years
The wetlands – degrading (Kingsford) and habitat
Flow (ML) to Marshes
No. of waterbirds
Number of species
No. of nests
Key River Murray Catchment Area
New horticulture up to 14 kilometres from the river
Estimates of up 32000 hectares since trade started
Nearly all outside “historic irrigation districts”
Water for the future: adjustmentAll figures in A$ million
Costing over ten years TOTAL: approx A$12.9 billion (about US$9 billion)
THE BASIN PLAN IS MADE
(some shared strategies)
Water Resource Plans
Water Sharing Plans
Water Allocation Plans
Water Sharing Plan
up to 2014
Industry and Individual water rights holders
New quality assured information required
Enable Commonwealth in conjunction with States to manage Basin’s water resources in the national interest
Give effect to international agreements, optimise economic, social and environmental outcomes
Ensure environmental sustainability and in this context, maximise net economic returns to the Australian community
improve water security for all uses of Basin’s water resources
(after Water Act 2007)
Climate is Hotter and Drier adjustment
Satellite estimate of soil moisture
Global average temperature
Australian average temperature
Warmer drier conditions in the future under all global emission scenario’s
Majority of models project reduced runoff for SE Australia, including Murray system headwaters
Projected changes in run-off at 2030 under scenario A1B, showing the number of climate models (out of 15) yielding an increase or decease in run-off; from F. Chiew.Future Projections
Monthly mean south eastern Australia rainfall, 1961-1990, 1996-2006 and anomaly
70 units adjustment
100 rainfall units
90 rainfall units
10% less rainfall
30% less streamflowRainfall & Streamflow(hypothetical catchment)
CSIRO and Australian Bureau of Meteorology, 2007)
Declining inflows for the Murray adjustment
Increased demand for groundwater as surface water availability reduces?
Higher evaporation. More farm dams as surface water availability reduces?
Increased forest evapo-transpiration due to higher temps?
Higher frequency and intensity of bushfires due to higher temps and worse droughts?
Greater irrigation efficiency as surface water availability reduces?
Other Impacts of Climate Change
Water market dynamics availability reduces?
Australia is now responding to a multifaceted availability reduces?
“water crisis” - symptoms include record low inflows
in the Murray-Darling Basin, water restrictions
in cities severe stress on many rural communities
and aquatic ecosystems – eg Lower lakes.
A “water crisis” without precedent, despite
“a long and proud history of water planning, the
impending crisis was largely unforeseen and its origins
are still poorly understood” (Schofield et al 2008).
Causes of the “crisis” - climate and land use change, availability reduces?
Australia’s inherent climate variability, with long droughts high rates of vulnerability – development based on high rates of water use.
Concerns about the reliability of Southern Australia’s water resources
Science more emphatic about the impacts of climate change, particularly the drying and intensification of droughts in the mid-latitudes.
Fears that the speed and scale at which climate change impacts are intensifying.
Conclusions availability reduces?
Conclusions availability reduces?
Extremely low water availability in the southern MDB
Impacts of the drought/climate change are
Long term reductions in rainfall and runoff likely
Policy and climate induced water scarcity
Intense competition for water
Adaptation and innovation is required and inevitable
Water policy, rural industries and irrigated agriculture will evolve
Range of policies required to support adjustment and adaptation