John C. Crittenden, Ph.D.

Sustainable Systems
Georgia Institute of Technology
Recruited: 2009

John Crittenden is one of the world’s leading thinkers on the holistic design of sustainable systems. His primary expertise is sustainable water systems for urban and agricultural use, and his work on these systems is informed by his decades of pioneering research on water treatment methods and technologies.
The depth and breadth of his research led the National Water Institute in 2015 to award Crittenden the Clarke Prize, one of the world’s most prestigious honors for water research.  
Crittenden’s early projects focused on granular activated carbon, which is used in some water treatment plants to hold toxic chemicals that have been filtered out of water and into the air. Crittenden developed a method to increase the efficiency of this process by reducing the humidity of the air before it is exposed to the granular activated carbon. The method he developed is now the industry standard.
Another of Crittenden’s key contributions is a mathematical model that enables engineers to quickly tweak and improve the design of a full-scale water treatment system while still in the planning stage. The model, called the Rapid Small Scale Column Test, helps simulate systems based on granular activated carbon.
Crittenden also contributed to another system that helps engineers evaluate water treatment strategies: a comprehensive software suite called the Environmental Technologies Design Option Tools (ETDOTs). This software package includes a database of hundreds of pollutants and the best approaches to remediate them. Using these tools, Crittenden and his colleagues helped NASA design a better water treatment system for the International Space Station; their system has been in use for several years.
The textbook Water Treatment: Principles and Design (2011), of which Crittenden was a senior author, is considered a classic text in the field and has sold more than 10,000 copies.
As director of Georgia Tech’s Brook Byers Institute for Sustainable Systems, Crittenden is bringing together a diverse group of experts to explore everything from technical processes to social decision-making in the design of more sustainable systems. As leader of this massive effort, he is an advocate of the idea that the only way to design truly sustainable systems is by looking at the big picture and understanding the many complex and interrelated variables.
Crittenden’s work is aimed at sustainability defined as “using only the resources that nature can provide and producing only the wastes that nature can assimilate.” Far from accepting deprivation, Crittenden seeks to help create a future where all of humanity can thrive and prosper in the long term. The strategies to accomplish this may be technological, policy-oriented, management-driven or all of the above – making his big-picture thinking more important than ever. 


  • Chemical treatment processes including ion exchange, oxidation processes, catalytic oxidation, photocatalytic oxidation, adsorption
  • Transport of organics in saturated and unsaturated groundwater
  • Modeling fixed-bed reactors and adsorbers
  • Modeling of wastewater and water treatment processes

Choosing Georgia

The Brook Byers Institute for Sustainable Systems at Georgia Tech offers an unprecedented opportunity to work with a broad range of individuals and groups from academia, business and industry, government, and non-profits to remediate the past, transform the present, and design the future for the benefit of people, the environment, and the economy. And as a state, Georgia is a favorable place for new ideas to seed and take root. To have the opportunity to conduct cutting edge research, have it widely acknowledged, and to see it directly applied is both satisfying and invaluable. Dr. Crittenden looks forward to seeing Georgia at the forefront of a sustainable 21st Century.