Planning for on-farm water shortage
Released 25 Aug 2008
Farmers in dryland areas are being urged to exercise restraint in the use of emergency water supplies provided for livestock purposes during periods of severe on-farm water shortages.
The Department of Water's rural water planning section is concerned that the supplies are being accessed for other purposes, and at times other than in an emergency.
The department's manager of rural water planning, David Hillier said the emergency water supplies should not be considered a day to day substitute for adequately developed, well managed and maintained on-farm supplies.
"The department plays a key water supply planning role working with dryland agricultural communities to prepare for seasons when low rainfall and limited run-off into farm dams and tanks cause on-farm water supplies to fail," Mr Hillier said.
"A network of strategically positioned emergency water supplies is being established to supply livestock water under emergency conditions when on-farm water supplies have been fully utilised."
"A key component in the planning is to ensure the availability of these supplies during extended periods of low rainfall, so that farming operations are secured."
"The emergency water supplies are provided from a mixture of dams, tanks and bores linked to surface water catchments or underground aquifers that are of varying capacity and reliability."
Mr Hillier highlighted the urgent need to manage Hyden's Allen Rocks emergency water supply more effectively – as concerns grow that demand on the groundwater resource now exceeds sustainable supply.
He said the Allen Rocks supply played a strategic role in providing emergency livestock water. However, the aquifer was a limited groundwater resource, and increasing salinity at the bore was also cause for concern.
Its increased use had prompted the department, in partnership with the Shire of Kondinin, to investigate impacts associated with groundwater abstraction at the site.
"In the interests of preserving Allen Rocks as a reliable emergency water supply for future years, access should be limited to emergency situations after on-farm supplies and other neighbourhood options have been exhausted," Mr Hillier warned.
"Taking water for non-emergency purposes should be avoided. If this is not possible, water should be preferentially taken from larger supply points in the area. For example: the rock catchment supplies of Kalgarin West Dam (Llewellyn's), Kings Rocks Dam and McGann's Rock Dam."
To maximise reliability of all emergency water supplies through a dry season, Mr Hillier recommended that larger stores should be preferentially used, and bore-water supplies not taken for non-emergency purposes.
"Large dams (for example Mount Madden) have a lower risk of failing during dry years than the smaller supplies (e.g. small dams, tanks and bores); and bore water supplies are typically limited in volume and sensitive to water-quality decline if over-abstracted."
"Ensuring reliable emergency water supplies requires cooperation from farmland communities, local government and state government agencies."
"Ongoing exploitation of emergency water supplies creates avoidable risk to farm operations and unnecessary stress to farmland communities."
For more information on emergency water supplies, or on-farm improvements contact the Department of Water's Rural Water Planning Program office on freecall number 1800 780 300 or refer to website: www.water.wa.gov.au For Allen Rocks emergency water supply, or alternative emergency water facilities in the region, contact the Shire of Kondinin on 9889 1006.
Contact: Dianne Dixon
Phone: (08) 6364 6983 / 041 991 0847