WATER IMPROVEMENTS AND SUPPLY


Water availability is dependent on:

Production return is affected by:



WATER IMPROVEMENTS AND SUPPLY

Water availability is dependent on:
Production return is affected by:


Environmental impact of inappropriate water use and management include: The following factors should be considered when evaluating a property's water supply:
Timber camps should not be established above a water point otherwise the supply may become polluted by the soil and manure washed into the dam. Bogging and pollution of a dam can be avoided by fencing the dam and pumping the water to a storage tank and troughs. This can be achieved with a small windmill or small pump.

New paddocks and a changed layout will require new water points. Where reticulated supplies are available this may be achieved simply by changing and moving the old lines. It is more difficult to provide water to new paddocks when the farm relies exclusively on dams, creeks and tanks. In such a situation it is better to pump the water to a large central elevated tank (turkey nest) and reticulate the water around the property by gravity.

An adequate supply of water is important because Australia is a dry country. A large part of a farm's water supply requires conservation of surface water or the tapping of underground supplies. A good supply of water, preferably town water, for the homestead, garden farm, buildings and for adjacent small paddocks is an advantage.

Tank water obtained from roof runoff can be used for domestic purposes.

WATER NEEDS OF STOCK

Temperature, type of pastures and humidity will determine the water needs of stock. Sheep are more tolerant of saline water than cattle and require less. Under normal summer conditions sheep running on dry grass may be satisfied with 4.5 litres or less per day. On the other hand in saltbush (pastoral) country watered by saline bores or wells, sheep may consume more than 20 litres per day.

The use of underground water for irrigation or homestead gardens is influenced not only by salinity but also the nature of the soil, drainage, climate and rainfall. Saline water can be used in light soil with good underdrainage and some plants are more tolerant of salinity than others (for example, native flowers). For example, water containing more
than 50 grams total salts/litre is commonly used to water lucerne in the Murray Basin where the soil drainage is particularly good.

The effect of salt build up is mitigated by using drippers instead of a spray or channel irrigation system. Hardness of water is generally not a problem for plant growth. In fact, many plants grow better with hard water.

Adequate and well spaced supplies of water will greatly reduce trampling of pastures, dust and erosion. Fencing lines should be arranged so that each watering point is accessible to stock in 2 or more paddocks. Dams should have easy access and be sited where they catch the best available catchments. The ground in which they are sunk should be reasonably impervious and free from drift veins that allow leakages.





Dams such as above are quickly and easily excavated using modern bulldozers and their relative construction cost is quite cheap. Their value is small compared with the other components of the farm system and therefore, are valued using the lump sum method.

WELLS AND SUBARTESIAN BORES

Where a satisfactory supply of underground water is available at reasonable depth it may be tapped by either a well or bore. A well is
a vertical shaft with a depth less than 30-40 metres whereas sub artesian bores are deeper and usually have 100 mm to 150 mm casings.
Water is raised using windmills (high capital cost but cheap running costs), piping, submersible pumps (the most efficient), cylinder pumps, jet pumps and foot valves with the use of an auxiliary engine during calm periods. The engine and pump are plant or chattels and therefore, not valued as part of the real estate.
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