Could changing irrigation methods in Australia save water, the agricultural sector and ultimately the Murray Darling Basin? “It can go a bloody long way towards it,” irrigation consultant Jeremy Cape told Crikey today.
Only 30% of irrigators actually use an objective scheduling method to find out when to apply water. What does that mean? According to Cape, it means that while the debate rages over sustainable cuts to irrigation entitlements for farmers on the Murray Darling Basin, only about half of the irrigated water in Australia is used by Australia’s agricultural plants. The rest is down the gurgler.
The alternative on offer is a standardised, water-efficient drip irrigation system, which allows the farmer to measure, within 5%, the amount of water being used.
While the loss of water through wastage is contributing to the overall ill-health of the river system, it’s also causing massive hikes in salinity which isn’t just bad for the river system, and has serious repercussions for irrigators and dry-land farmers as well. Wentworth Group environmental engineer Tim Stubbs says water that drains below the root zone and into underground water tables draws the water — and a lot of salt — to the surface.
“Australia’s landscape has a lot of salt in it. Because of damming and catchments we’re not getting flood planes and carbon moving, and we’re then getting massive build-ups of salt levels which makes the water salty,” he explained. “Up in Queensland around the Burdekin catchment they’ve been irrigating for 20 years now, and they’re really starting to see the effects of salinity. Sugar cane production levels are dropping.”
Cane, who has worked in the irrigation sector for over 20 years, reckons the proposed water entitlement cuts could be easily met by farmers, and salinity levels could be much better managed if more efficient methods of irrigation were supported by the government.
“In 1990 we had about 40 people employed in water usage efficiency by the NSW Department Agriculture. Now there are less than five. The support for extension staff who are working to support irrigators has virtually disappeared in the public sector,” he said.
“There used to be a rural Water Use Efficiency in Queensland and this program no longer exists. It is possible to change methods of irrigation, meet those targets and maintain the health of the agriculture sector all at the same time.”
Sean Hoobin is the fresh water policy manager from the World Wildlife Fund and agrees the cuts proposed must be met if the process is going to carry any real environmental weight
“There’s been a range of cuts recommended, and the ones being looked at by the government aren’t going to do the job. If we’re going to do this we may as well do it properly,” he said.