1. Senior Irrigation Engineer, Irrigation Training and Research Center, California Polytechnic State Univ., San Luis Obispo, CA 93407 (corresponding author).
2. Professor, Dept. of BioResource and Agricultural Engineering, and Chair, Irrigation Training and Research Center, California Polytechnic State Univ., San Luis Obispo, CA 93407.
3. Professor, Dept. of Civil and Environmental Engineering, Univ. of California, Irvine, CA 92697.