In the case of cotton, despite its gross margins being higher than most broad acre rainfed crops, farming systems which include high yielding cereals grown on limited water are proving as profitable per megalitre of water (Garcia de Figueiredo and Rodriguez, 2007). This is the reason why more and more growers see themselves as ‘irrigation growers’ rather than as cotton growers, and are interested to identify opportunities that maximize farm profitability. Under this scenario and in view of present and future trends in climate and water availability (IPCC-WGI Fourth Assessment Report, 2007), the greatest threats for irrigators, as identified by the Scoping Study CCC CRC (McRae et al., 2007) are:


  • the impact of increased variability and decreased reliability in water supply,
  • the lack of capability and guidance on how to transform irrigated farms into profitable and viable irrigation farm businesses,
  • the formulation of mitigation policies designed by governments ignoring the economic-social-environmental consequences of alternative policy options.

In addition to present drivers for change, future climate change suggests 16-25% reduction in average Murray-Darling stream-flows by 2050 and 16-48% reduction by 2100 (Pittock 2003; Christensen et al 2007). This is likely to have dramatic implications for irrigation water allocations in the Riverina (Jones and Pittock 2003) and other parts of the Murray-Darling system; for example, Jones and Page (2002) suggested that a 15% drop in annual rainfall by 2030 would mean a 50% reduction in irrigation allocations for the Macquarie catchment. These projections mean that irrigation enterprises might need to implement both adaptive and major transformational changes, i.e. farming practices and farm businesses strategies/re-location, respectively, to ensure the long term viability of their business.

Clearly, increased climatic variability, ongoing structural adjustment, and expected climate change make the increase in preparedness and adaptation to change an urgent and unavoidable task for our irrigation industries. Better prepared (i.e. better informed and capable to act), and adapted (i.e. improved agronomic practice and more resilient farm business designs), are paramount to increase water productivity. We believe that productivity gains need to be found at both the paddock/single enterprise, and the whole farm business levels.

At the paddock level irrigation efficiency (yield/ha) could be improved by:

  1. Reducing evaporative water loss through the delivery system to the crop, by changing irrigation systems.
  2. Reducing drainage and runoff losses by matching water application rates to crop demand (deficit irrigation) and soil capabilities.
  3. Increasing grain yield per unit of applied water, by the strategic use of suboptimal irrigation amounts.

At the whole farm business level irrigation efficiency ($/ML) could be improved by:


  1. Designing more resilient and profitable farm businesses, e.g. enterprise mix, resource allocation, scale of the business, reduction in overhead costs, contracting vs. own machinery.
  2. Optimising water allocation between alternative enterprises across all sources of water (runoff, river and bore) and soil types.
  3. Improving the profitability – risk profile of the farm business by changing cropping intensities and quantifying and improving the management of risks (i.e. climate and economic).







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