1. Senior Engineer, Infrastructure Planning Branch, Water Corporation, 629 Newcastle St., Leederville, Western Australia 6007, Australia; formerly, Centre for Water Research, Univ. of Western Australia, Australia (corresponding author)..
2. Professor, Centre for Water Research, Univ. of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia. E-mail: jimberger@cwr.uwa.edu.au