Reclaimed Water for Irrigation of Vegetables on a Sodosol in the Werribee Irrigation District, Victoria S. Engleitner, F. Barker-Reid, M. Wos a , R. Faggian, and A. Boland b Department of Primary Industries Victoria Melbourne, Australia Current Address: a National Research Centre for Biotechnology, Braunschweig, Germany b RMCG, Melbourne, Australia Keywords: red brown earth, salinity, pathogens, organochlorines, broccoli, lettuce Abstract In 2005, an experimental site was established to investigate the effects of saline reclaimed water on irrigated vegetable crops in the Werribee Irrigation District (WID). Results from the first two crops (broccoli and lettuce) are presented. Results to date indicate that Class A reclaimed water contained no detectable biological contaminants. Both thermotolerant coliforms and E.coli were detected in river water, the traditional source of water for the WID. Preliminary results indicated that the salt content, in both the neat reclaimed and shandy water, caused no significant yield decrease in broccoli but lettuce yields may be reduced where soil is already affected by salinity and where irrigation is insufficient to meet both crop demand and leaching requirements. INTRODUCTION Melbourne’s Werribee Irrigation District (WID) is located in a coastal area, about 30 km from Melbourne’s central business district and adjacent to Melbourne’s Western sewage treatment plant (WTP). Production is intensive with 3-4 crops per year predominantly consisting of rotations including broccoli, cauliflower and lettuce. Total water rights (river and bore) of almost 10,000 ML/year are shared by 161 customers on 266 irrigated holdings and cover 2857 ha of irrigated land, of which 2086 ha are used for market garden production (SRW, 2006). Recent drought conditions provided the impetus to seek alternative sources of irrigation water other than the Werribee River and bore water (i.e. groundwater). In January 2005, reclaimed water produced by the WTP became available to WID growers in the form of a mixture or “shandy” of river and reclaimed water, in an effort to reduce salt loads to ~1400 μS/cm. By 2009, treatment processes will be established to reduce reclaimed water salinity to ~1000 μS/cm, which is considered a sustainable water salinity level for vegetable production (MW et al., 2004). Until that time, many local growers will rely upon the higher salinity shandy water. Although previous research on reclaimed water for vegetables has been conducted in Victoria, even the most relevant work is not directly applicable to the WID as both soil type (sandy loam) and irrigation water salinity (900 μS/cm) were different (Kaddous et al., 1986). Site-specific research is important in evaluating the risks associated with the addition of salt and nutrients (from irrigation water) to agricultural soils. In this case, the application of saline water has potential impacts on soil health and structure, as well as plant nutrition and