1. a Department of Civil Engineering , University of Canterbury , Private Bag, 4800, Christchurch, New Zealand E-mail:
2. b Water Assessment Group , Natural Resources and Water, Queensland Government , Indooroopilly, QLD, 4068, Australia E-mail:
3. c School of Civil and Environmental Engineering , The University of Adelaide , Adelaide, SA, 5005, Australia
4. d School of Civil and Environmental Engineering , The University of Adelaide , Adelaide, SA, 5005, Australia Phone: Fax: E-mail:
5. e School of Civil and Environmental Engineering , Cornell University , Ithaca, NY, 14853-3501, USA E-mail: