Reclaimed water for irrigation of vegetables on a Sodosol in the Werribee Irrigation District, Victoria

In 2005, an experimental site was established to investigate effects of saline reclaimed water for irrigating vegetable crops grown in Red Sodosol in the Werribee Irrigation District (WID). Results from the first two crops (broccoli and lettuce) are presented. Class A reclaimed water contained no detectable biological contaminants (thermotolerant coliforms, Escherichia coli, Enterococcus spp., Salmonella spp.) Water salinity did not affect broccoli yield but lettuce yield was reduced by both undiluted reclaimed water (EC 1800 mu S/cm) and mixed water (reclaimed+river; EC 1400 mu S/cm) compared with river water (EC 400-700 mu S/cm). Reclaimed water contained agronomically important quantities of nitrogen (16 kg N/ha/ML irrigation). Due to inefficiencies associated with surface runoff, the leaching fraction currently recommended to lettuce growers within the WID appears to be too low. Results indicate the leaching fraction should be increased from 17% to approximately 33% (for water EC = 1800 mu S/cm).