Ralph B. Hwang, Ph.D., P.E., F.ASCE

Special Recognition Award

The following is the text found on the Special Recognition Award presented to Ralph B. Hwang at the California Extreme Precipitation Symposium held at the University of California, Davis on June 23, 2015.


Presented To

Ralph B. Hwang, Ph.D., P.E., F.ASCE
Emeritus Professor
Director, Office of Hydrological Studies
Department of Civil Engineering
California State University, Sacramento

Sustainable, successful flood risk management in California requires a sustainable cadre of meteorologists and hydrologic and hydraulic engineers. Dr. Ralph Hwang has contributed greatly to satisfying that requirement through his distinguished career as a California State University, Sacramento professor and advisor to students and researchers in water resources engineering.

Dr. Hwang has influenced the development and thinking of thousands of young professionals through his 36 years of teaching and research. When recalling Dr. Hwang, these students emphasize his dedication and commitment to their education, which contributed greatly to their successful careers. Many of the students have gone on to work within water management in California, evaluating, planning, designing, operating, and maintaining facilities that manage flood risk throughout the state.

Through applied research, Dr. Hwang has produced more than 200 papers and technical reports. Dr. Hwang developed inundation mapping procedures for the State of California, and many other states have adopted the same standard. His other accomplishments include reviewing dam failure inundation maps for the State, developing precipitation-runoff models, and developing strategies and models for sediment transport and streamflow simulation.

This award recognizes Dr. Ralph Hwang's outstanding contributions to flood risk management during his many years of service to the profession, which have made the people of California safer from flooding.

California Extreme Precipitation Symposium
June 23, 2015

Professional Experience

Dr. Ralph Hwang.
Dr. Ralph Hwang

Dr. Ralph B. Hwang, Ph.D., P.E., F ASCE, is an Emeritus Professor in the Civil Engineering Department at California State University at Sacramento, where he taught for 36 years.

While at CSU Sacramento he has advised and mentored more than 50 graduate students for their MSc degrees, and received more than $1,218,000 in funded applied researches leading to 22 papers and 187 technical reports.

Dr. Hwang developed and wrote the "Sequence of Steps in Dam Break Inundation Map Preparation" for the California Governor's Office of Emergency Services (Cal OES) that was officially adopted in the California Code of Regulations, Title 19, Public Safety, Division 2, Chapter 2, Subchapter 4, Dam Inundation Mapping Procedures. These mapping procedures have become the standards for all non-federally owned dams in California since 2002. Most of the other states also adopted the same standard.

Dr. Hwang's other accomplishments include:

  • Developing seven stream flow simulation computer models for predicting stream flow from rainfall data in the Russian River Watershed
  • Developing strategies and predictive models for sediment transport and stream flow simulation
  • Carrying out over 182 large dam failure inundation map reviews for Cal OES to determine maximum dam breaching outflows and resulting inundation maps under the extreme dam break scenarios
  • Authoring Groundwater Hydrology, published in 1991
  • Numerous teaching awards
  • Outstanding Scholar Award in 2002
  • In recognition of his 20 years as advisor to the Tau Beta Pi chapter at California State University at Sacramento he was honored with the Superior Service Award


  • Ph.D.: University of California, Davis
    Water Resources Engineering
  • M.Sc.: University of Saskatchewan, Canada
    Hydrologic Engineering
  • M.Sc.: National Taiwan University
    Hydraulic Engineering
  • B.Sc.: Chung Yuan University
    Hydraulic Engineering

At the Event