纽约市是一个有800万常住人口的现代化大都会,虽然哈得逊河和东河两条河流经纽约,但因濒临大西洋,河水是咸的,而且河上船只往来频繁,有污染,水质不好,所以纽约从建城开始就挖井取水。到19世纪中叶,由于城市迅速膨胀,井水已无法满足需要,纽约开始设法从城外引水。离纽约100多英里的北边,是一片林木茂盛的山地,有许多干净的水源。纽约市在那里逐步建成了水库供水系统,所有用水全靠这些水源地供应。现在每天的供水能力达到13亿加仑(1加仑相当于4.55升),是全球最大的供水系统。这片水源地约2000平方英里,包括19个水库和 New York City is a modern metropolis with 8 million resident population. Although the two rivers, the Hudson and the East River, pass through New York, the river is salty because of its proximity to the Atlantic Ocean, and the ships on the river are frequent, polluted, and have poor water quality. So New York started digging and collecting water from the beginning of the city. By the middle of the 19th century, as the city expanded rapidly and well water could no longer meet its needs, New York began to manage to divert water from outside the city. Located more than 100 miles north of New York, it is a lush hill with lots of clean water. The New York City has gradually built a reservoir water supply system there, and all water is supplied by these water sources. With a daily water supply capacity of 1.3 billion gallons (1 gallon is equivalent to 4.55 liters), it is the world’s largest water supply system. This water source is about 2,000 square miles, including 19 reservoirs and