Mexico City’s Grim Paradox: Thirst in a Wet Land of Floods

For days at a time, sometimes even weeks, Rosa Maria Camacho doesn’t take a bath, wash clothes or cook for her large family.

She’s not on strike or giving up household chores in favor of afternoons of leisure.

It’s just that some days there is no water. And on those days, she and her husband, four children and three grandchildren have to put their daily lives on hold.

“You can’t do anything--wash the clothes, take a bath--anything,” she said. “Imagine living without water when you have two babies in the house.”

Living without water is a sacrifice that has come to be expected by Camacho and thousands of others in this sprawling metropolitan area of 18 million people.

Water--how to get it and preserve it--is “the gravest and most difficult problem facing Mexico City,” said Sergio Zaldivar, an architect for the federal government.

Rain Is Plentiful

The irony is that unlike the desert-dry northern Mexican states where a worsening drought has been killing cattle, withering crops and drying out taps in recent years, Mexico City is awash in rainwater.

It’s drenched with about four times what it consumes each year, said Fernando Menendez Garza, an ecologist and founder of the metropolitan environmental commission. “But we don’t have the infrastructure to capture it.”

Menendez’s firm recently completed a study in conjunction with city and federal agencies that proposes a series of dams to capture and store some of the rain.

If adopted, it would be a big break with the past.

Instead of seeking ways to use water from the torrential downpours that wallop the city during the rainy season, government leaders dating back to the Aztecs have spent all their resources expelling it.

That’s because Mexico City is built on lake beds in a closed basin with no natural drainage, so it has been besieged for hundreds of years by devastating floods. One that hit in 1629 lasted nearly eight years and forced half the city’s population to move to nearby Puebla.

Modern-day planners developed an expensive, complicated network of channels and pumping stations that divert rain into rivers and on to the Gulf of Mexico.

While the plentiful rains are sent down the drain, the city drills deeper and deeper to find drinking water. Sixty percent of the area’s water supply comes from underground aquifers that are shrinking, city officials say.

Going Down

The persistent overuse of the aquifers has resulted in another problem: the slow and steady sinking of the city. The city’s central plaza--site of the national palace and the imposing metropolitan cathedral--has sunk 26 feet in the last century.

As the ground subsides, the 7,460 miles of underground water pipes are breaking, so 37% of the water pumped into the system is lost to leaks.

Sewers also are snapping, allowing sewage to seep into the ground. “There is the danger that the subterranean aquifer will get contaminated and then Mexico City loses all of its water supply,” Menendez said.

A project begun by the city government in 1998 to repair pipes has thus far fixed only a quarter of the leaks, he said. And if the city’s sinking continues, the replacement pipes--although made of stronger, more flexible materials--could break too.

In addition, because water is being drawn from ever-greater depths, it contains more salts and minerals, making it less drinkable.

If the city doesn’t do something to come up with new sources of water, in 20 years a third of the population will be without water, Menendez said.

The problem already causes water shortages in various parts of the city, especially during the dry season at the beginning of the year. When pipes dry up, Camacho and other families must rely on city trucks that distribute drinking water in affected neighborhoods.

At those times, Camacho uses bottled water to cook and reuses water whenever she can. She also knows not to plan: Water that may be running at 8 a.m. could suddenly stop at 2 p.m.

The city’s uncontrolled growth is worsening the problem.

From 1940 to 1999, the metropolitan area--which includes the federal district of Mexico City plus about 50 municipalities in the state of Mexico and one in the bordering state of Hidalgo--has grown from 200 square miles to more than 2,000 square miles, said the city’s former environmental secretary, Alejandro Encinas.

Because of land scarcity, much of the growth has crept into forest areas where rainwater seeps down into the city’s aquifers. Illegal squatters who build homes and peasant farmers who have more incentive to sell wood than to save forests have degraded the forests’ ability to absorb water.

Each year, an average of 1,500 acres of land are lost to the conservation areas, and that means the loss of 315 million gallons of water to the aquifers, Menendez said.

“At the same time, the population is demanding water,” he said. “We are going to have a terrible gap” between demand and supply.

Meanwhile, Mexico City’s external water sources--34% of its water comes from rivers in Mexico and Guerrero state--may soon dry up because those areas are growing and will need the water for themselves.

Although the city built a huge pipeline 10 years ago to take water from the Temascaltepec River 90 miles away, the people of Guerrero state have refused to release the water.

Menendez’s proposal, which is supported by the Inter-American Development Bank, is to build a series of dams that would catch rainwater and allow it to filter into the underground aquifers.

Although the engineering details need to be worked out, he estimates the project would cost $127 million. That compares to the $350 million required to pump water uphill 3,940 feet from the Temascaltepec River--a project that in any case is no longer viable.

“It is absurd that the water we receive we throw out and then we’re left taking water that belongs to other people,” Menendez said.

Another essential part of his plan is to halt growth in the conservation areas. It proposes creating financial incentives for peasant owners to preserve rather than destroy the forests and public education programs on the importance of preservation, conservation and recycling.

Menendez also wants to do a study on recycling water, which would allow factories and farms to use treated water and sewage instead of valuable drinking water.

“We have to create a new culture where we take advantage of the rainwater, reduce the amount we are using, and re-treat the water we use,” said Encinas, the former environmental secretary.

“Without a doubt we are going to have to arrive at some new habits in the short run in this city. The viability of this city depends on it.”