1 Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX, Delft, the Netherlands. e.raj@un-ihe.org.
2 Civil and Environmental Engineering, E321 Engineering Quad, Princeton University, Princeton, NJ, 08544, USA.
3 Institute of Chemistry, Bioscience and Environmental Engineering, Faculty of Science and Technology, University of Stavanger, Box 8600 Forus, 4036, Stavanger, Norway.
4 School of Civil Engineering, Southeast University, Nanjing, 210096, China.
5 Gujarat Pollution Control Board, Paryavaran Bhavan, CHH Road, Sector 10A, Gandhinagar, Gujarat, 382 010, India.