In the 1990s New York City was at a turning point with its drinking water and needed to build a new water treatment plant to filter its water supply. The foreseen budget was 8–12 billion dollars plus 300 million dollars annual maintenance fees for the new plant. 

Instead they decided to invest in the surrounding ecosystem. This meant buying up natural lands and protecting them from development, funding septic system upgrades and infrastructure repairs in the watershed communities and offering financial incentives for farmers to shift to non polluting agricultural practices. In 1997 the New York City Watershed Memorandum of Agreement was adopted.

The ecosystem service strategy cost only 300 million dollars, saving the city billions of dollars and protecting an essential eco-service now and into the future. Every day 1.2 billion gallons of water travels, mostly via gravity, from the Catskills providing 90% of New York’s drinking water. The bonus in the process is the Catskill Mountains watershed not only provides clean and affordable water that doesn’t require major treatment, but also the beauty of the region is protected.