Hydro-climatic modelling workshop UNSW - MDB Water policy challenges and innovation

Transcription

1 Hydro-climatic modelling workshop UNSW - MDB Water policy challenges and innovation Presenter: Jason Alexandra Director Water Policy Coordination April 2009

2 Overview 1. Background 2. Challenges 3. Brief History 4. Water policy in context 5. Climate change 6. Conclusions

3 Understanding the ecological realities of Australia "Charles Darwin. Visited Sydney in 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.

4 Despite headline these warnings successive Australian governments have tamed the rivers and made the deserts copy 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

5

6

7 Modified catchments, nutrient and suspended sediment loads and habitat Very high nutrient and suspended sediment loads Largely unmodified in all aspects Catchment Condition

8 Australian water era 1890 s 1980 s Development era drought, royal commission, new dam 1992 Industry Commission TWE 1994 COAG reforms environmental flows, unbundling water and land titles ; corporatisation and cost recovery 1995 MDB Cap on development National Water Initiative 2004 reaffirms reform agenda and markets role in reallocating water

9 Area (x1000 ha) Irrigation The biggest user of diverted fresh water Produces more than half the profit in Australian Agriculture & Horticulture, from 0.5% of land (NLWRA 2002) NSW Vic Qu SA WA Tas

10 Government funded development of dams Major periods of water diversions (note Murray average inflows approx 9,000,000 ml) 18,000,000 12,000,000 Murray Darling 6,000,

11 The MDBC has an Engineering An engineered system Heritage

12 The Murray an exotic river Less than 10% of it s catchment yields > 90% flow Large in scale but less flow in an average year than the Amazon in a day Highly variable heavily exploited water resources Highly developed but thus high vulnerability Future health influenced by climate change, landuse, bush fires, forestry and water resources policy reform

13 Water policy in context Complexity Scarcity vulnerability to variability Changes in irrigated agriculture Global commodities boom Green-fields sites for new investment Government buy backs, policy reforms and modernisation Purchases of environmental water Drought and/or climate change

14 Water a complex business

15 Is this Drought Different? Key River Murray Catchment Area

16 An Irrigation Drought several dry years June ,220 GL

17 Irrigation crop and technology changes Water use efficiency through technology, Knowledge of crop demands eg partial root zone drying

18 Global demand for food Surge in cereal and oil prices Commodity prices (US$/ton) Corn Wheat Rice Oil (right scale) Jan-00 Jul-00 Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Jul-06 Jan-07 Jul-07 0 Source: Data from FAO 2007 and IMF 2007.

19 Greenfield developments New horticulture up to 14 kilometres from the river Estimates of up hectares since trade started Nearly all outside historic irrigation districts

20 Water for the future: All figures in A$million Costing over ten years TOTAL: approx A$12.9 billion (about US$9 billion) Water information Reform MDBC Northern Aust and Great Artesian Basin Modernising Irrigation Addressing over-allocation Modernising and Extension Investigations and strategy Info. Management and reporting Analysis and forecasting Set and administer a new cap MDBC operations Modernising and Extension Investigations and strate Info. Management and repo Analysis and forecasting Set and administer a new cap MDBC operations Northern Aust and Northern Great Aust and Artesian Great A Basin On farm efficiency On farm efficiency Metering, monitoring, acc Improving river operation Metering, monitoring, Delivery system accounting efficiency Purchasing entitlements a Improving river operation Delivery system efficiency Purchasing entitlements

21 Water Resource Planning BEFORE THE BASIN PLAN IS MADE Basinwide issues (some shared strategies) Water resource plan area issues NSW Water Sharing Plans VIC Bulk Entitlements SA Water Allocation Plans QLD Water Resource Plans ACT Water Sharing Plan Local issues generally up to TBA 10 years 15 years 5 years 10 years TBA Industry and Individual water rights holders

22 Post Basin Plan AFTER THE BASIN PLAN IS MADE Basinwide issues AUSTRALIAN GOVERNMENT BASIN PLAN Water resource plan area issues NSW VIC SA QLD ACT Water Resource Plans Water Resource Plans Water Resource Plans Water Resource Plans Water Resource Plans Local issues TBA 10 years 10 years 10 years 10 years 10 years Industry and Individual water rights holders

23 Key Elements of the Basin Plan

24 Information demands New quality assured information required To support the plan Risk assignment Determine how much water is available How much has been reduced by climate change

25 Water for the environment Commonwealth committed $3 billion for purchases Most buy back focused on entitlements paper water Move to land and water purchases Allocations could be bought for the environment Some experience of buying real or wet water eg Narran lakes

26 Narran Lakes watering MDBC (March 2008) agreed to purchase $2 million allocation water for the Narran Lakes Water used on March & April 2008 Approximate price per ML - $180 Water sustained the Narran Lakes levels Water delivered: 30,000 ibis, spoonbills, ducks etc Cultural significance international recognition

27 Climate is Hotter and Drier Global average temperature Satellite estimate of soil moisture Australian average temperature

28 Future Projections Global emissions tracking on the higher IPCC scenarios 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.

29 Actual Decreases in Runoff

30 Rainfall Change (mm / month) Drier Autumns Monthly mean south eastern Australia rainfall, , and anomaly Anomaly Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

31 100 rainfall units 90 rainfall units Rainfall & Streamflow (hypothetical catchment) 30 units streamflow 20 units streamflow 70 units evaporation, transpiration & soil moisture threshold 70 units evaporation, transpiration & soil moisture threshold 10% less rainfall 30% less streamflow

32 Lower rainfall = much lower Streamflow CSIRO and Australian Bureau of Meteorology, 2007)

33 Declining inflows for the Murray Source:

34 Disproportionate Impact of Climate Change: Victorian high 2055 impact Valley reduction in total inflows reduction in allocations reduction in environmental flows Murray - 33% - 10% - 44% Broken - 46% - 6% - 66% Goulburn - 36% - 23% - 55% Campaspe - 67% - 45% - 84% Lodden - 70% - 67% - 73%

35 Other Impacts of Climate Change Higher evaporation. More farm dams as surface water availability reduces??? Climate change??? Increased demand for groundwater as surface water availability reduces? Greater irrigation efficiency 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?

36 Maximum reduction in yield: Vic 2003 fires: Reductions of up to 1237 GL/y in 20 years

37 Risks from farm dams Potential impacts from new dams to 2030

38 Water planning with market dynamics Water market dynamics in a climate of change and uncertainty: Value up due to scarcity needed to protect high capital permanent plantings Impacts of government buybacks $3 billion Higher prices for outputs due to global food scarcity Greenfields developments competing for available water

39 Conclusions Pressure for better information: Intense political and community interest Drought responses rural and urban Irrigation structural adjustment New horticultural and viticultural developments Future drivers and directions of irrigated agriculture (investor confidence) Rebalancing extractions and environmental water

40 Conclusions Extremely low water availability in the southern MDB Impacts of the drought/climate change are unprecedented Long term reductions in rainfall and runoff likely Policy and climate induced water scarcity Intense competition for water Adaptation is inevitable Water policy and irrigated agriculture will evolve Range of models, information and policies required to support adjustment and adaptation

41 For more information: