Who We Are

Johnson C.C. Yeh, Ph.D., PG, CHG

Principal Geohydrologist and Groundwater Modeler

Dr. Johnson Yeh is a principal and lead groundwater modeler at Geoscience. During his more than 27 years of career, he has been involved in the project management of the firm’s groundwater modeling efforts, including some of its most high-profile geohydrologic investigations, groundwater basin/water quality studies, and artificial recharge projects. Dr. Yeh also possesses a broad knowledge of GIS tools utilized in support of modeling work and oversees Geoscience’s GIS staff members.

Dr. Yeh spearheads the generation and quality control of technical documents and technical presentations to both clients and regulators, including leading training and workshops on the use of models to the USGS and USEPA.


Education and Professional Credentials:

B.S., Geology, National Taiwan University, 1981
M.S., Geology, National Taiwan University, 1984
Ph.D., Sedimentology with an emphasis in Statistical Analysis, University of Southern California, 1991
California Professional Geologist (No. 6317)
Certified California Hydrogeologist (No. 422)