1. Research Assistant, Ven Te Chow Hydrosystems Laboratory, Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana and Champaign, 205 N Mathews Ave., Urbana, IL 61801 (corresponding author). E-mail: liu19@uiuc.edu
2. Chester and Helen Siess Professor, and Director, Ven Te Chow Hydrosystems Laboratory, Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana and Champaign, 205 N Mathews Ave., Urbana, IL 61801. E-mail: mhgarcia@uiuc.edu