Maintaining livestock water supplies in drought and other adversities

Tuesday, May 16, 2023

Stock Journal Feature, November 2022

Author: Mary-Anne Young, PIRSA

Water excesses are probably more on peoples’ minds than deficiencies this spring but now is a good time to consider the property’s long term water requirements and how they can be met in times of drought or “emergencies” such as a truck crashing into a River Murray pipeline, cutting off all supplies.

Just as people who get cut off by floods or are put under quarantine need to have food and water on hand for several days to carry them through, stock also need feed and water readily available on farm for days if not weeks.

An audit of a property’s water requirements, sources, storage and distribution and consideration of back-up options, enables greater flexibility and ability to cope when things don’t go according to plan.

Farms mostly source water from:

  • “Mains” water – from a river or reservoir;
  • Rainfall and runoff that is captured or “harvested”;
  • Underground water which can have low to extreme salinity.

Storage on-farm is a key factor in maintaining supplies over a period of time, using dams or tanks. Open dams can store greater volumes of water and are relatively cheaper per litre of water but prone to large losses (up to 50%) from evaporation and leakage. They are restricted in their positioning and in most catchments, also subject to regulation.

A consistent supply of fresh, good quality water in every grazing paddock improves livestock condition and enables better pasture utilisation. Some farmers with rotational grazing systems use water distribution to move livestock from one paddock to another when animals come into water. Water reticulation through pipes should use appropriate pipe sizes and pump pressures to maintain a reliable flow. A number of devices are available to monitor water supplies, flows and consumption as well as detect leaks in systems.

Calculating a property’s water requirements should include all water uses on the property – household, garden, wash-down areas, shearing shed facilities, fire-fighting, broadacre spraying, as well as livestock. Livestock water needs vary enormously over a year according to an animal’s age, feed supply, and sex (i.e. pregnant / lactating) and environmental conditions. For example, 1 DSE (Dry Sheep Equivalent) needs nearly 6 litres per day when grazing high protein stubbles over summer but while on green feed in winter will only need a litre per day at the most.

PIRSA, working with the Barossa Improved Grazing Group and the Agricultural Bureau of SA, has developed a Planning Water Supplies for the Farm handbook and tools for calculating livestock water requirements and doing a property audit. Links below: 

Planning on Farm Water supplies.pdf

Worksheet to calculate livestock water requirements and runoff calculations

Worksheets to undertake Water Infrastructure Audit