1. Graduate Research Assistant, IIHR-Hydroscience and Engineering, Dept. of Civil and Environmental Engineering, Univ. of Iowa, Iowa City, IA 52246-1585.
2. Professor and Goodrich Chair of Excellence, Dept. of Civil and Environmental Engineering, Univ. of Tennessee, Knoxville, TN 37996-2313 (corresponding author).
3. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Univ. of Tennessee, Knoxville, TN 37996-2313.