纽约市有三个水库系统，但只过滤巴豆系统。由于过滤需要几年时间，而且由于巴豆源水需要保护以避免进一步污染，该市的流域保护计划将适用于巴豆、卡茨基尔和特拉华流域。1988年，该市开始制定一项全面、长期的流域保护计划，旨在:减少和清理现有污染源；通过未来的发展防止水源污染；改善整个系统的水质，尤其是现在富营养化的水库。纽约市的流域保护计划是各种组成部分的综合组合，包括:严格的流域法规和执行；与流域社区的伙伴关系；收购敏感流域土地；加强科学和工程研究；以及流域内所有污水处理厂的升级改造。

New York City maintains three reservoir systems, but will only be filtering the Croton System. Because filtration is several years off and because Croton source waters need protection from further contamination, the City's Watershed Protection Program will apply in the Croton as well as the Catskill and Delaware watersheds. In 1988, the city began to develop a comprehensive, long-term watershed protection program designed to: curtail and clean up existing sources of pollution; prevent pollution of source waters by future development; and improve water quality throughout the system, particularly in reservoirs that are now eutrophic. New York City's watershed protection program is an integrated combination of varied components that include: stringent watershed regulations and enforcement; partnerships with watershed communities; acquisition of sensitive watershed land; increased scientific and engineering research; and upgrading of all wastewater treatment plants in the watersheds.