New York's water supply

The water comes from a system of 19 reservoirs and three lakes in upstate New York -- some flowing to the city from as far as 125 miles away. Most of the supply is protected and filtered by the natural processes of upstate ecosystems. It dissolves natural minerals while traveling over land or through the ground. One advantage of the system is that 95% of the total water supply is supplied by gravity.

It is, after all, one of the nation's healthiest water supplies -- so fresh that in 2007 the Environmental Protection Agency said it did not need filtration. New York pizza and bagel makers have long credited local water as a special baking ingredient. It goes down soft, without hints of tart-tasting minerals or chlorine like other public water systems.

• The Croton system, the oldest and smallest, sits in Westchester and Putnam Counties.
• The Catskill system, built decades later, is significantly larger than the Croton. In the early years of the 20th century, the city and state designated thousands of acres of land in the eastern Catskill Mountains to build two reservoirs that more than doubled the city's capacity.
• In the 1950s and 1960s, the city expanded its water system again, tapping the east and west branches of the Delaware River, as well as other tributaries of the Delaware and Hudson rivers to create the newest and largest of its three systems, the Delaware system, which provides around half of the city's water supply.^[2]

http://www.gcswcd.com/wap/
http://en.wikipedia.org/wiki/New_York_City_water_supply_system
http://www.treehugger.com/files/2006/04/graham_asks_can_1.php
http://articles.latimes.com/2009/feb/25/nation/na-tapwater25