As others have mentioned, the main approach to maintaining quality drinking water has been through conserving watershed integrity. Adherence to the filtration avoidance criteria are a great basis for protecting the water supply and has led to a massive project on controlling the watershed. The costs of acquiring lands, setting rules and regulations, and initiating programs to protect the watershed are all justified for the protection of water. Prevention, making sure that pollutants do not enter the water in the first place, is a much less expensive and more desirable means of maintaining quality than filtering. However, leaving water unfiltered does mean that measures like these are not enough, especially if NYC govt agencies are primarily concerned with public health. Using chlorine to disinfect is only the most basic step. With microbial pathogens, especially antibiotic-resistant strains, toxic compounds, and other harmful substances in the water, money should be invested in technology that can detect and control these. Additionally, monitoring of content in the water and disease surveillance is extremely important if the city’s agencies want to stay aware of the drinking water quality. The National Research Council found that NYC’s monitoring program to be “informed”, “extensive”, and “of high quality”, but there is room for improvement. NRC suggests analyses of groundwater, randomly checking tap water in homes, and conducting rick assessments on Cryptosporidium. These are not cheap to perform, but would be important complements to an unfiltered system.
Though it is in the City’s best interests to find a cheaper way to protect the water, this is just the local agencies’ wants for the short run. If and when the quality of unfiltered water becomes too difficult to manage, the supply system will have to filtered. This is not undesirable to agencies like the EPA, who value healthy and clean water foremost, but balancing watershed management and water treatment is a big question of agencies with limited resources. As the NRC mentions in the conclusion, watershed management planning “is not a guarantee of permanent filtration avoidance”. With the growth of populations along the watersheds, and subsequent economic development, rules and regulations about activity in these areas cannot be considered a foolproof solution. Neither can simple disinfection and on-site inspections. It is in the local agencies’ best interest to continue pushing for environmental health of the basin and water source, but also to begin pursuing the more expensive technological treatments like filtration. It may seem obvious but, basic protection of the watershed area is the foundation of managing safe drinking water, which means that it needs to be both expanded into other measures when necessary, and well-maintained even when other measures are included.
Ehlers, Laura J., Max J. Pfeffer, and Charles R. O’Melia. “Making Watershed Management Work.” Environmental Science & Technology 34.21 (2000): 464A-471A. General Science Full Text (H.W. Wilson). Web. 2 Dec. 2012.
http://pubs.acs.org.remote.baruch.cuny.edu/doi/pdf/10.1021/es003466q
