About Marie



Problem Solver


Marie Pearthree has over 38 years of experience in the water industry. She has held a wide variety of positions in consulting engineering, hydrology and water utility management, including Deputy Director of the Tucson Water Department where she led the team that successfully brought in Colorado River water to the Tucson area. At CAP she held the position of Assistant/Deputy General Manager, where she oversaw Colorado River programs, resource planning, water policy and strategic initiatives. She has since co-authored the book “Tucson Water Turnaround: Crisis to Success” with Michael J. McGuire. A Registered Professional Engineer (Civil) in Arizona, she holds a Bachelor of Arts degree from Oberlin College in Geology and a Master’s of Science degree in Geosciences from the University of Arizona.


  • Author: “Tucson Water Turnaround: Crisis to Success” published in 2020 by the American Water Works Association with co-author, Michael J. McGuire (2016-2020)
  • Central Arizona Project: Assistant/Deputy General Manager overseeing Colorado River Programs, resource planning, water policy, and strategic initiatives (2009-2016)
  • Tucson Water Department: Program Manager, Water Treatment Administrator and Deputy Director in charge of the Tucson Water Turnaround team that successfully delivered CAP water (1997-2008)
  • CH2MHill: Principal Project Manager/Senior Management Consultant (2008-2009)
  • Cella Barr Associates, Tucson: Hydrologist; Manager, Hydrology Dept., responsible for surface water and aquifer assessments, floodplain management studies, and drainage design; Business Development Manager. (1981-1985 and 1987-1995)
  • Pima County Flood Control District: Principal Hydrologist (1985-1987)


  • City of Tucson Public Service Excellence Award (2003)
  • Select Society of Sanitary Sludge Shovelers, AZ Water Association (2007)
  • George Warren Fuller Award from the AZ Water Association/American Water Works Association (2018) 

Professional Affiliations

  • AZ Water Association – Member; Board of Directors including President and Annual Conference Chair (2015-2018)
  • American Water Works Association – Member; Water Utility Council (2000-2004, 2013-2016); Director-at-Large (2009-2012)
  • Association of American University Women – Member

Marie and husband Phil, with daughters Genevieve and Kristin