Al Preston, Ph.D., P.E.

Al Preston, Ph.D., P.E., is a Senior Engineer based in California with more than 16 years of experience leading and managing complex water resources projects involving hydraulics, hydrodynamics, and hydrology. He specializes in developing and applying hydrologic, hydraulic, hydrodynamic, nutrient, biological, water quality, climate-change, and computational fluid dynamics models to water resource problems.


Al assists his clients with modeling and analyses of storm channels, rivers, dam breaches, lake and reservoir hydrodynamics, coastal ocean environments, and groundwater. With a strong technical background in the fundamentals of the underlying physics and fluid dynamics, he can help clients readily assess model appropriateness for a given application and provide quality assurance of model results.

Al is currently leading hydrologic and hydraulic modeling efforts for the high-profile Los Angeles River Master Plan update for Los Angeles County Public Works, working with Frank Gehry Partners and OLIN landscape architects.  Analyses includes developing and using traditional models developed by the U.S. Army Corps of Engineers, as well as state-of-the-art computational fluid dynamics models to fully evaluate the complex flow at confluences and bridges. 

Previously, Al lead the development of the peer-reviewed three-dimensional hydrodynamic and water quality model for Lake Mead.  He subsequently led and managed projects using the model to situate a new drinking water intake, examine the effects of a deep-water diffuser discharge, track perchlorate through Lake Mead and the Lower Colorado River, and investigate the effects of climate change on water quality. Other modeling experience includes pathogens and bacteria; hypolimnetic oxygenation; pump-back schemes between reservoirs of vastly different water qualities; reservoir drawdowns for construction and other purposes; and reservoir expansions, including mathematical optimization of port elevations in newly designed dams. Al also has extensive experience helping clients model effluent and thermal discharges in rivers and brine discharges associated with desalination plants in coastal ocean waters.

Contact Al Preston at This email address is being protected from spambots. You need JavaScript enabled to view it. or +1-310-957-6115.

Career Summary: Al Preston, Ph.D., P.E.

  • Specialties: Water Quality Modeling, Dam Breach Modeling, Desalination Brine Discharges, Climate Change, Groundwater Modeling
  • Practice Areas: Water and Natural Resources
  • Disciplines: Civil Engineering, Mechanical Engineering
  • Education: Ph.D., Mechanical Engineering, California Institute of Technology, Pasadena, CA, 2004; M.S., Civil Engineering, California Institute of Technology, Pasadena, CA, 1997; M.E., Mechanical Engineering, University of Canterbury, Christchurch, New Zealand, 1997; B.E., Civil Engineering, University of Canterbury, Christchurch, New Zealand, 1994
  • Registration: Professional Engineer, California, License No. 77904
Geosyntec Consultants
Geosyntec is a consulting and engineering firm that works with private and public sector clients to address new ventures and complex problems involving our environment, natural resources, and civil infrastructure.

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