1. Assoc. Prof., Hydr. Res. and Testing Fac., Civ. Engrg., Univ. of Manitoba, Winnipeg, MB, Canada R3T 5V6. E-mail: doerin@cc.umanitoba.ca
2. Hydr. Res. and Testing Fac., Civ. Engrg., Univ. of Manitoba, Winnipeg, MB, Canada R3T 5V6.
3. Sr. Engr., Manitoba Hydro, Winnipeg, MB, Canada R3C 2P4.