Salinity Province 128, Werribee

The Werribee Salinity Province is a moderate sized province located on the western edge of the Melbourne metropolitan area. It covers about 10 km either side of the Princes Highway/Freeway from the suburb of Sunshine, to an area about 10 km west of the Werribee urban centre. About 20 % of the province is urbanised (mostly in the province’s east and centre), the remainder being a mix of small dryland agricultural enterprises (mostly grazing on improved pastures) and ‘Hobby Farms’. The small Werribee Irrigation Area is also located within the province, southwest of the Werribee urban area; landuse in this area involves intensive agriculture including flowers and vegetables. Being designated growth areas, major residential developments in the east and centre of the province are likely to have significant effects on its catchment hydrology and associated soil & water salinity.

About 0.9% of the province is mapped as saline, which is generally associated with discharge on the floodplains beside major rivers and in low-lying coastal regions, many of which have watertables within 2 metres of the surface. Salinity management options vary with the different Groundwater Flow Systems (GFS) present and with the presence or absence of irrigation. Details for each GFS and the irrigation vs dryland areas can be found in the PPWCMA report "Salinity in the Port Phillip and Westernport Region” (see link below). However, in general, control options for public and other non-agricultural land include fencing off and establishing salt tolerant (preferably native) vegetation in discharge areas and installing arterial drains to lower watertables in new urban land development areas. On agricultural land, control options include; establishing salt tolerant (native where possible) perenial pastures in discharge areas and groundwater pumping to reduce watertables (where suitable aquifers and viable disposal options are present), and the finding of alternative uses for saline drainage water e.g. aquaculture.