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Townsite salinity in Western Australia : background and history

Townsite salinity and the Rural Towns Program

Salinity is a major environmental problem threatening the existence of many country towns in the low and medium rainfall areas (<600 mm/year) of Western Australia's agricultural region.

Damage to people's homes, public buildings, roads and railways, destruction of concrete structures, sporting grounds, parks and gardens, dams and reservoirs are some of the symptoms of townsite salinity.

Historically, country towns were built to support agricultural communities and included facilities for transporting produce to major ports and cities via rail. Because the rail system was constructed in the lower sections of the landscape, the towns also tended to be located in hollows or lower slopes. This location has been a prime reason for the development of salinity in lower lying towns while towns in the upper landscape do not have significant problems.

Although the causes of salinity in rural towns are similar to those affecting agricultural land, there are a number of factors which can make townsite salinity problems worse, including:

the location of towns low in the landscape within surrounding agricultural catchments;
disruptions to natural surface runoff and infiltration caused by high shedding surfaces, e.g. roofs and paving;
the use of imported scheme water within towns; and
alterations to surface and subsurface water movement within towns due to subterranean man-made structures which divert or impede water flows.

Rural towns also contribute a significant amount of recharge to groundwater through:

irrigation of parks, gardens and sporting grounds;
water supply dams which may leak into the local groundwater system;
inefficient drainage schemes which fail to prevent runoff from roofs, roads and other structures;
use of septic tanks and leach drains within some towns rather than reticulated sewerage systems; and
leakage from water pipes and sewerage lines.

Accordingly, increased groundwater infiltration affects the water balance in the town relative to its wider catchment. All of these factors mean that townsite salinity is more complex than salinity management problems within the surrounding agricultural land.

If you have any questions about Townsite Salinity, please visit our Frequently Asked Questions page.

Page last reviewed July 2005

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