MEXICO : Progress and Promise : Environment : From Lerma River Flows a Tale of Politics and Pollution : * Farmers, industry and government all use and abuse the once-pristine water resource. The result is an ecological disaster.

For the first time anyone could remember, the Virgin came to the lake, the guest of honor at a thanksgiving celebration.

Carried on the shoulders of the faithful, the yard-high image of the Virgin of the Rosary, brought here by Spanish missionaries in 1531, led the procession through cobblestone streets to an outdoor Mass. Villagers, who credited her intercession for replenishing their lake, cheered as the statue was set on a makeshift altar composed of a small boat with draped fishing nets as a backdrop.

“How beautiful it is to see our lake filled to the flood walls,” the priest exclaimed as the sun set over the mountains above Lake Chapala. “Let us give thanks for the rain the Lord has sent us, this water sent to fill our lake.”

After decades of shrinking, Mexico’s largest lake rose nearly three feet this year. It’s still barely one-third of the size that it was as recently as 20 years ago, when Josefina Hernandez bought handfuls of its famous white fish for a peso, then worth 8 cents. Still, three feet is enough to rekindle hope in this fishing village turned resort. “We are so thrilled to see our lake this high,” said resident Josefina Villegas. “We just hope it can continue.”

Whether the lake continues to rise depends less on the Virgin and another year of record rains than on politics, said meteorologist Enrique Flores, director of a University of Guadalajara research institute that has studied Lake Chapala for over a decade. “What really filled the lake was political will,” he said.

In an election year, and at a time when Mexico’s environmental record is a major issue in discussions of a proposed North American free-trade agreement, a shrinking Lake Chapala was embarrassing evidence of ecological irresponsibility, according to Flores. Mexico could hardly convince environmentalists that it is taking a firm stand to protect nature when foreign tourists clearly saw that the lake D. H. Lawrence once described as “like a sea,” was actually drying up.

Flores said that the sluice gates of seven major dams along the Lerma River--the source of 80% of Lake Chapala’s water--were opened this year to fill the lake. Water was supposed to have been released last year but wasn’t, leading him to believe that it required a high government order to force local officials to cooperate. The dams were built to generate electricity and supply water for irrigation along the Lerma’s 309-mile route through Mexico’s densely populated industrial heartland.

The lake is only one contender for the river’s water: Mexico’s two largest cities and hosts of farmers and factories all make claims--modern needs and traditional lifestyles fighting for the same resource.

As a result, the Lerma now provides only one-sixth as much water to Lake Chapala as it did a decade ago. And that water is so badly polluted that the Lerma is considered second only to Mexico City on a list of national ecological disasters.

A trip down the Lerma is a tour of Mexico’s challenges as it tries to modernize without further damaging its environment.

It’s a tour past towns, factories and refineries that draw water from the river and return wastes. Farmers along the way combine the most wasteful and polluting of old and new agricultural techniques. They irrigate fields with open ditches that allow a third of the water to evaporate; fertilizer and pesticides run off to drip back into the river. A visitor also finds evidence of a $52-million government plan to halve pollution in the Lerma and to increase the flow of water into Lake Chapala by 10%. But two years after the project was announced, actual results are scant.

The first attack on the Lerma comes before the river even gets started at the town of Almoloya del Rio, on the outskirts of Toluca. Fresh springs at the headwaters of the Lerma used to flow so abundantly that they also supported 14 mile-long Lerma Lake. Francisco Gutierrez, 63, fished and boated there when he was a boy. “There were birds and frogs, and the water was crystal-clear,” he recalled, leaning on a scythe he uses to harvest oats from what was once the lake bed.

But in 1950, workers building an aqueduct to nearby Mexico City misplaced some dynamite, and the resulting explosion virtually destroyed the springs, disrupting the water supply all along the river.

“This is all that is left,” Gutierrez said, waving a calloused hand at a dirty trickle of water in an open irrigation canal. The canal flows from what remains of the headwaters, a stream of dark water strewn with trash and choked with water lilies.

Fishermen carrying nets cross footbridges over the Lerma on their way to favorite spots in nearby marshes. Do they ever fish in the river? They look at the water, turn up their noses and laugh.

But this is just the beginning.

The Lerma industrial corridor, nine miles downstream from Almoloya, has become a model for Mexican development. There are already seven more such corridors and plans for eight more--homes for factories to provide jobs for the country’s burgeoning population.

Over 200 factories in the Toluca-Lerma Industrial Zone send their waste water to a single state-run treatment plant--a stream of pollution equivalent to sewage from a town of 800,000 and the biggest purification job assigned to any such facility in the country. Built nine years ago, it is the forerunner of 45 more plants being constructed as part of the government anti-pollution plan for the Lerma.

The facility was designed to remove a wide array of pollutants from the water--trace metals, detergents, organic materials, oil. And a sign outside proclaims the treated water “95% clean” and usable in agriculture and industry.

But some are skeptical as they watch white foam floating on stinking brown sludge emerge from the plant. “Phosphates,” concluded chemical engineer Briseno Muniz. “I can tell by the color that it contains heavy metals, lead and mercury. It is criminal, a public health hazard, to use that water for irrigation.”

Asked about their sign, plant officials still insist that the water is safe.

The people of La Concepcion, 40 miles downstream from the treatment plant and across the river from the Pasteje Industrial Park, trust their eyes and noses, not signs.

“The water stinks,” said Angela Lara Lopez. “It is polluted.” Following the tradition of women who have lived in the village since its founding in 1523, she used to wash clothes in the river. But no more.

As the Lerma flows north, it begins to clean itself in the 23 miles to Atlacomulco, a village known for its peaches and cattle. Irrigation water from the river has been a staple of local agriculture. But nowadays, Atlacomulco is industrializing.

PepsiCo, U.S. chemical manufacturer Reichold and various local companies already have plants along the highway that crosses the Lerma, and developers are trying to attract more. Drainpipes from the industrial park lead to the river.

Another 30 miles downstream, at Tepuxtepec, is one of the first dams built across the river to generate electricity. Jose Soto was just 9 years old in 1926 when he and his mother came to join his father who was helping to build the dam. They had to walk 17 hours from the nearest railroad station.

Eventually, Soto would spend 32 years working in the electrical plant. But before that, he earned his living fishing in the huge artificial lake formed behind the dam. “Fish hatched upstream would swim into the lake and up to the dam,” he recalled. “They would get confused, and there we would be with our nets to pull them out by the ton. All kinds of fish. These days, boys fish all day and just get a few carp.”

The artificial lake has grown with two additions to the dam, needed to provide more and more electricity to power-hungry cities. The most recent 15-foot addition in 1972 flooded rich farmland. The farmers were finally paid for their losses last spring after a 19-year legal battle.

Water that cascades through the turbines at Tepuxtepec flows south and then west through the rolling hills of Michoacan. Now the industrial parks are left behind, replaced by fields where bean vines wrap around cornstalks, providing the two staples of the Mexican diet in a farming method used since pre-Columbian times.

In all, the Lerma and its network of dams provide irrigation for 250,000 acres of farmland in three states--a lifeline for men like Uvaldo Lara.

Lara is a member of the Guadalupe ejido, a communal farm that surrounds a hillside village of rutted streets, open sewers and concrete blockhouses. It is one of 14 ejidos --27,100 families in all--that receive water from the nearby Solis Dam.

“Each farmer is allowed to irrigate 15 acres,” Lara said of his ejido. “We get two harvests a year from the irrigated land,” one-sixth of the total acreage. The second, irrigated winter crop is usually sorghum, wheat or alfalfa--crops that bring in money or provide feed for livestock. Rain-fed lands are only good for subsistence farming in corn and beans.

“If it weren’t for the dam, we would be flooded now,” said Lara, a husky man with a graying mustache, who even indoors wears the white palm hat that is the trademark of Mexican farmers. He remembers floods in 1964 and 1973, before an additional 15 feet was added to the dam in 1978. “We lost the whole harvest and some houses also. The whole valley flooded.”

The problem, according to scientists at the University of Guadalajara, is that during a drought in the early 1950s, farmers began planting in the flood plain of the Lerma. When normal rainfall resumed later, their crops were flooded and they demanded action: raise the dams.

What no one took into account was that flooding provides a natural renovation of the land, a new layer of topsoil. Once the flooding stopped, farmers became more dependent on chemical fertilizers. And that also damaged the river.

Maps, for example, show a lake behind the Solis Dam. But what visitors see is a floating field of water lilies nurtured by the river’s high nitrogen levels, the result of agricultural runoff from fields with chemical fertilizers.

As it flows on into Guanajuato state, the Lerma runs into new sources of pollution.

The government-owned Pemex petroleum refinery in Salamanca is a major supplier of gasoline and petrochemicals. It also produces a black tar that spills into the Lerma within sight of highway Route 45.

Pemex is expected to be more of a factor in future pollution. A refinery torn down in March because it polluted the Mexico City air is being reassembled here.

Ten yards downstream, the Federal Electricity Commission dumps more waste water into the river.

Both Pemex and the Electricity Commission signed the pledge to clean up the Lerma two years ago, promising to build treatment plants at their facilities on the river. Officials now say that engineering is completed on both plants and the projects will be put up for construction bids before the end of this year.

Farmers around Salamanca no longer use the Lerma’s contaminated water for irrigation. They pump water from ever-deeper wells, causing the area’s water table to drop a yard per year.

As the Lerma turns south, it is joined by the Turbio River, carrying nitrates and salt from the tanneries of Leon. And on its final leg it flows past 133 pig farms that supply most of central Mexico’s pork.

“These farms are the worst source of organic pollution on the river,” said Rogelio Garcia Castro, another member of the University of Guadalajara research team.

Since 1988, Mexico’s environmental protection agency has shut down pig farmers caught dumping manure into the river. Farmers said they no longer dump, but people who live along the riverbanks say disposal has simply become covert.

As the river flows out of Guanajuato at La Piedad to form the state line between Jalisco and Michoacan, the stench is almost unbearable. A sign near the highway announces that a treatment plant able to process 60 liters of waste water per second is under construction, part of the effort to clean the river. But at the site, a lone construction crane sits idle, amid mounds of dirt.

By the time the Lerma reaches the Chapala Marsh, a 34-square-mile area that was once part of the lake, measurements by University of Guadalajara scientists show that each million parts of river water contain over 500 parts of detergent, 100 parts of sulfate, and 50 parts of chloride. The fecal content is frequently 50 times the maximum recommended for water intended for recreational use or irrigation. Lead, mercury and nickel are present.

The polluted Lerma waters have so contaminated Lake Chapala that efforts to stock the lake with fish over the last 20 years have been futile. The lake’s famed whitefish are nearly extinct, and even carp have difficulty surviving.

“People should not be drinking this water,” said University of Guadalajara researcher Enrique Flores. Nevertheless, Guadalajara draws three-fourths of its water--540 million cubic meters a year--from the lake. And 133 million cubic meters more are used to irrigate farms on Lake Chapala’s southern shore.

Instead of relying so heavily on the Lerma and Lake Chapala, Flores and his team have proposed that Guadalajara build a series of sophisticated cisterns to collect water during the rainy season for later use.

Saving the lake is important not only for the sake of beauty and tradition, but because the huge body of water affects rainfall and climate in a broad region, said scientist Garcia Castro.

Without the evaporation from Lake Chapala, rain will decrease in central-western Mexico, turning fertile farmlands to desert. The moderate Guadalajara climate that draws U.S. retirees to the area will become more extreme.

However, saving the lake will be difficult because of all the conflicting interests that must cooperate.

“Cleaning Lake Chapala will take just as much effort and resources as reviving Lake Erie,” Flores said, referring to the Great Lake north of Ohio that until a major cleanup a decade ago was too polluted to support life. “The question is whether there is the political will to do it.”