Water Stewardship – Australia
Improving quantity and quality
Australia’s cotton industry is considered among the most water-efficient in the world. Appropriate varieties, a world-class research effort, use of the latest technologies and cutting-edge farm practices all combine to produce Australian cotton fibre that is farmed with less water per hectare than ever before.
Over a decade, the Australian cotton industry has invested nearly $30 million in water and irrigation research, development and extension extending across the crop, field, farm and industry scales. This enormous R&D effort helped the Australian cotton industry achieve a 42% increase in water productivity in the decade between 2004 and 2014, meaning cotton water usage improved 3-4% every year.
In the 2016/17 cotton season, 77% of Australia’s cotton area was irrigated, with 23% rain grown. Cotton is mostly grown in the 400-800mm summer rainfall zone, which means cotton crops can receive significant amounts of their water needs from rain during the growing season. The cracking clay soils where cotton is grown can store up to 150-170mm of plant available water in a 130cm profile, especially following a wet winter prior to cotton planting.
Water is a highly regulated resource in Australia. Irrigators pay for access to their water, and they are strictly licenced to ensure the environment, towns and stock get their water needs met first. Cotton is an ideal crop for Australia’s climatic conditions (prone to droughts and flooding rains) because cotton is only grown when there’s water available. In times of drought, cotton simply isn’t planted.
High uptake of irrigation technologies
The improvements in cotton water usage in Australia are the result of significant practice changes and plant breeding. Australian cotton growers are fast adopters of technology, and water use is no exception.
Examples of farm management changes to improve cotton water usage include:
- 70 percent of farmers use soil moisture probes, up from 40 percent in 2006 (highest of all agriculture industries in Australia)
- 96 percent of irrigators have improved their furrow irrigation system or changed to an alternate irrigation system
- 49 percent of irrigators had made changes to the flow or size of their siphons
- 35 percent have redesigned fields
- Other practices include irrigating to deficits, better accounting of soil variations, changed bed shapes, using irrigation scheduling probes, furrow irrigation system optimisation evaluations, pump optimisation and reducing distribution losses
Growers are quickly changing to alternative irrigation systems such as centre pivots and lateral move systems, and it is expected there will be an increasing number of these machines in the future.
- “The Australian Cotton Water Story – a decade of Research & Development 2002-12”: Published by Cotton Catchment Communities CRC Limited, 2012. http://www.cottoncrc.org.au/industry/Publications/Water
- Cotton Australia Water Fact Sheet: http://cottonaustralia.com.au/cotton-library/fact-sheets/cotton-fact-file-water
- Cotton Australia Fact Sheet – Practical Approaches to Water Use Efficiency