Drinking Water Treatment

Sustainable technologies for water supply are urgently needed if water has to be supplied to billions of less fortunate people with inadequate access to water. These technologies must be simple, less expensive, less energy intensive, and easy to maintain for their adaptation among the poor masses.

Four appropriate technologies are discussed here: solar pasteurization, membrane desalination, natural filtration (riverbank filtration), and solar distillation. Solar pasteurization can be a useful means of producing water at remote, but sunny locations where fuel may not be easily available for boiling water. Membrane desalination will remain as a viable means of drinking water production for individual households to large communities. Various membrane filtration techniques as well as the means to 'democratize' membrane filtration have been presented. Riverbank filtration is a 'natural' filtration technique where drinking water is produced by placing wells on the banks of rivers. The riverbed/bank material and the underlying aquifer act as natural filters to remove pollutants from river water. Solar distillation can be a viable method of drinking water production for individual households to small communities without the input of external energy. Sustainability framework and technology transfer are discussed through transdisciplinary analysis.

Chittaranjan Ray is Professor of Civil & Environmental Engineering and Interim Director of the Water Resources Research Center, University of Hawaii, Honolulu, Hawaii. Prior to joining the University of Hawaii, he worked as a research scientist at the Illinois State Water Survey at the University of Illinois. He received his Ph.D. in Civil Engineering from the University of Illinois at Urbana-Champaign and an M.S. degree in Civil Engineering from Texas Tech University. He was also employed as a staff engineer in the firm of Geraghty & Miller, Inc. in Hackensack, New Jersey (USA) conducting hazardous waste site investigation and water supply development for communities. He is a fellow of the American Society of Civil Engineers. He has published 5 books, over 100 scholarly papers, and many technical papers. His research work has been funded by the US National Science Foundation, US Environmental Protection Agency, US Department of Agriculture, US Department of Defense, and other agencies.

Ravi K. Jain is Dean, School of Engineering and Computer Science, University of the Pacific. Prior to this appointment, he has held research, faculty, and administrative positions at the University of Illinois (Urbana-Champaign), Massachusetts Institute of Technology (MIT), and the University of Cincinnati. He received degrees in civil engineering (BS, MSCE) from California State University. He holds a Ph.D. from Texas Tech University and a Masters in Public Administration from Harvard University. He has directed major research programs for the US department of Defense and has served as chairman of the Environmental Engineering Research Council, ASCE. He is a member of the American Academy of Environmental Engineers, a fellow of ASCE, and a fellow of AAAS. He has been a Littauer fellow at Harvard University and a fellow of Churchill College, Cambridge University. He has published 14 books, over 150 scholarly papers and technical reports, and has received many awards and honors including the US Army's highest research award and was a recipient of the NSPE Founders Gold Medal and named Federal Engineering of the Year for 1989.