Like many other fast-growing cities around the world, Mexico City is facing severe water shortages. Many of its 20 million inhabitants receive only one hour of piped water per week. Others receive none at all for weeks on end. Those who can afford the expense build their own home water system to catch and keep rainwater to supplement the city water. The situation, according to intemational experts, is the result of a combination of factors. First, the system of pipes is old and poorly managed, with the result that the pipes lose almost 40 percent of the water that they distribute aroundthe city. Second, the demand for water, which has grown with the rapid population growth, far exceeds the supply. Furthermore, the water is consumed not only by residents for household use, but also by thirsty industries such as beer-brewers and soft-drink bottlers, and there is little incentive for them to conserve or recycle water.
The current water shortages in Mexico City contrast remarkably with the city's situation in the past. When the Spanish arrived at the Aztec Capital in 1519, they destroyed the buildings, and began draining the water from the lakes to build what became Mexico City. For the next four centuries, the city was able to meet its water needs from springs, shallow wells, and the remaining lake water. In the mid-nineteenth century, the residents of the city began taking water from the underlying aquifer. In the twentieth century, as water needs grew and supplies from the aquifer became inadequate, city authorities brought water up from two nearby river systems. Twenty-five years ago, they began piping in water from 80 miles (130 km) away. Because Mexico City is located on a highland, the water must all be pumped uphill at considerable expense