Environment: Squatter settlements are chipping away at protected zones. Officials hope measures will contain the damage.

By SUE FOX
Times Staff Writer

MEXICO CITY -- At the end of the rutted road to San Miguel Xalpa, where squat cement houses and soccer fields choked with dust give way to a lush forest,
Mexico City has flung up a "Green Wall."

It's not much of an obstacle. It's not even a wall, this government sign planted in the dirt, declaring itself the Muralla Verde and warning would-be settlers to go no
farther. They have ignored it, by the tens of thousands, trooping into the woods to build primitive houses among the 100-year-old pines.

The migration--some call it an invasion--has shaved trees from hillsides like unwanted stubble. Wooden shanties sprout in their place almost overnight, followed by
roads, electric cables and water pipes. Bricks and cinder blocks turn rickety shacks into permanent homes.

Haphazard growth is nearly synonymous with Mexico City, whose immense expansion from the 1960s to the 1980s has made it the world's second-largest city and a
virtual case study of urbanization run amok. Now, less than five years after it began electing its own mayors, the capital is seeking to contain the damage, an
experiment that probably will be closely watched by mega-cities from Rio de Janeiro to Cairo.

Mexico City's squatter settlements are a particularly virulent form of urban sprawl, driven by poverty, corruption and lax environmental enforcement. Authorities in
the Federal District, which is similar to the District of Columbia, estimate that 65,000 illegal homes with as many as 260,000 people occupy forests and farmland
designated as conservation areas throughout the city's southern end. More than 5,000 families settled in protected zones during the last year. The Green Wall itself is
now well within the conservation zones.

Squatters Adding to Environment Problems

The creeping mancha urbana--urban stain--increases air pollution and erosion as trees that once absorbed contaminants and anchored soil vanish. More important,
unfettered urbanization threatens the aquifers beneath the forests and meadows, which provide 70% of Mexico City's water.

"It's probably the main environmental problem facing the city," said Claudia Sheinbaum, the Federal District's environment minister. "This region represents the main
area where rainwater infiltrates the soil and recharges the aquifer. The urbanization of the forests means less water."

Unlikely as it may seem for a city notorious for searing pollution, Mexico City remains one of the world's greenest metropolises. More than half of the acreage in the
Federal District, whose border matches that of the city, is designated open space, and a full quarter is carpeted by forests. More than 8 million people live in the
district, mostly in dense urban neighborhoods on the city's northern side, while 10 million more live in the greater metropolitan area within the Valley of Mexico.

Last year, the Federal District lost about 800 acres of green space to urbanization, officials estimate, depriving the aquifers of 160 million gallons of water. The city
uses 300 billion gallons of water a year.

Illegal logging and insect infestations also are chipping away at the conservation areas.

The Alamo family crossed the Green Wall a year ago, hauling corrugated tin and composition board into a sun-flecked grove deep in the Magdalena Contreras
forest. The Alamos built a one-room home, decorating the walls with flattened orange juice cartons and a crucifix. Iron skillets hang from a rotting stump beside the
door.

Juan Alamo Perez, a stooped construction worker, moved his wife and four young children into the forest after the family was evicted from its apartment in San
Bernabe, a poor neighborhood in the western area of the city.

"The rents were so high that we could not find an affordable apartment," he said. Now the Alamos live for free, along with half a dozen other families in their fledgling
settlement, using electricity and water pilfered from city systems through illegal hookups.

Families Live on Dreams of Suburbia

But life is not easy in the mountains that cradle this ancient city. None of the Alamo children attend school, and they catch cold easily in the chilly weather. Their father
struggles to hold a job, commuting each day by hiking through the forest to a road and then catching a bus downtown.

A hundred yards away, on the other side of the Green Wall, the Alamos can catch a glimpse of their potential future. That's where San Miguel Xalpa, a 15-year-old
settlement that began as a cluster of squatters' shacks, has swelled into a suburb of about 3,000 people.

Though still modest, the two-story brick and stucco homes offer an array of comforts. Indoor plumbing is standard, and some houses feature stained-glass windows
and cable television. At one bright purple home, a man could be seen on a recent afternoon hosing down his Plymouth Voyager in his gated driveway, the picture of
suburban domesticity.

Like many such areas, San Miguel Xalpa has become "regularized," its once-outlaw status legalized by the government. The system benefits just about everyone, at
least in the short term: Poor families find homes, local politicians win votes by promising public services for the shantytowns, and construction companies cater to
homeowners.

Wealthy people also sometimes build homes illegally in protected areas, Sheinbaum said.

For decades, government officials have looked the other way as development seeped into the mountains. The development increased after an earthquake struck the
capital in 1985, killing thousands of people and pushing hordes of residents out of the urban core.

"Every hill in Mexico City is being invaded," said Homero Aridjis, a prominent Mexican poet and head of the Group of 100 environmentalists. "Supposedly this is
protected territory, but there is no authority there. We have this combination of protective policies and under-the-table deals. Corrupt politicians induce invasions,
and then they take a piece of the cake for themselves and build their own houses. The landscape is gray, the color of cement."

Squatters also have set up camp in areas designated for agriculture. In Xochimilco, an area known for its canals, many wetland plots earmarked for horticulture are
studded with illegal houses. Last year, the urban stain grew 23% in the area--the greatest increase citywide--and local authorities have been forced to provide
portable toilets to the newcomers.

"Every week we discover more houses," said Patricia Perez Hernandez, Xochimilco's subdirector of urban development. "On the one hand, the government should
not provide services for these people, because they are illegally building on the land. But if we ignore them, the water gets polluted."

In Mexico, the problem of uncontrolled urbanization extends beyond the capital, where population growth has slowed to about 3% a year. In areas surrounding the
city, squatter settlements have popped up even on the fringes of middle-class towns. And in the coastal state of Guerrero, thousands of poor people this month
claimed a stretch of shoreline near Acapulco. In a rare government crackdown, President Vicente Fox dispatched a team of prosecutors that will seek to evict them.

"The phenomenon is so widespread that it is almost impossible to fight," said Victor Lichtinger, Fox's environment minister. "We will choose to defend a few
important areas where the environment is very sensitive, but we need to prevent invasions before they happen, not after."

Because land takeovers often are led by political bosses shortly before an election, Lichtinger said, electoral reform is a good place to start. He suggests barring
squatters from registering to vote in local elections until they have lived in a spot for several years, thereby killing the short-term incentive for politicians to organize
invasions to win votes.

Programs Designed to Halt the Sprawl

In Mexico City, officials are trying a different approach. They have tightened environmental laws, prohibiting new developments of more than 10 homes in some
southern neighborhoods and sharply increasing the penalties for illegal land use. The capital also has launched a program to build 10,000 apartment units a year for
settlers living in illegal areas.

The government also doled out $15 million last year to farmers, triple the amount of previous years, in an attempt to shore up agricultural production so that farmers
won't sell their land to developers.

For Maria Elia Lara Tenorio, a florist who grows 20 varieties of roses on the banks of the Magdalena River, the subsidies have meant the difference between sickly
flowers and glorious blossoms. Last year, her collective of seven women received a $40,000 government grant to renovate their greenhouses. With improved
insulation and irrigation, Lara's flowers fetch five times the money they once did at market, she says.

"We are much better off than we were a year ago," she said. "Many people sell their land when they cannot profit from agriculture anymore, regardless of how the
land will be used. But now I wouldn't think of selling it to anyone."

Slowly, financial incentives and public education programs may take root among the natural stewards of the land: the people who live there.

"The forest is the source of human life," said Miguel Casas Albarran, a white-haired peasant who has lived among the trees all his 75 years and now works for a
water conservation project. "If we don't take care of it, we will all perish."

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Rafael Aguirre in The Times' Mexico City Bureau contributed to this report.