Dealing with salinity in Wheatbelt Valleys - Department of Water

esponse to town flooding. Over 100 kilometers of level banks were constructed and to date, similar
rainfall events have not resulted in severe flooding in town.
In 1986 drilling was commenced to look at salinity risk in the town and catchment. Like the Belka,
watertables are rising at rates of 0.1-0.3 m/yr. However unlike the conclusions of Bettenay twenty years
before, research in the mid-1980s and 90’s indicates there is a high salinity risk in the Merredin type
valley, with groundwaters now within 3-5 m of the towns CBD.
Salinity management has included a range of measures; tree planting and trial pumping and associated
desalinisation and evaporation of water is planned. The bus tour will travel through areas in town likely
to develop watertables within the root zone, including the conference venue. The route will allow
discussions of the impact of the Department of agriculture Rural Towns Program, Shire and local
community efforts.
Travelling west, the bus will pass the Merredin town dams, revegetation areas where over 33,000 trees
(for wood and water use) were planted in 1991, major CBH handling centre, Dryland Research Institute
and proposed evaporation basins before returning to Merredin for the Civic Reception.
A detailed set of notes on the Merredin section is available and several Conference papers will refer to
engineering, salinity risk and resource opportunities for the use of saline groundwater (e.g. see Ali and
Coles, George and Coleman, Jones and others). In addition maps of the Belka and Merredin catchment
will be available at the Conference, showing present salinity and predictions of areas with a likely
shallow watertable.