1. Chf. Engr. and Genl. Mgr., Los Angeles County Sanitation Districts, Los Angeles, Calif.
2. Div. Engr., Los Angeles County Sanitation Districts, Los Angeles, Calif.
3. Assoc. Prof. of Civ. Engrg., Calif. Inst. of Tech., Pasadena, Calif.; Consultant to Los Angeles County Sanitation Districts, Los Angeles, Calif.