15 April 2004

Lake Chapala: A Tragedy of the Commons

When Juacabo Bacilio Loza casts his net into Mexico’s Lake Chapala, he catches fewer and smaller fish than he did 10 years ago. Heavy metals now contaminate his reduced haul and he no longer captures whitefish, once the lake’s prized catch. “I’ve been fishing since I can remember,” the 42-year-old Loza said as he prepared for the peak fishing season. “That’s what my father did and I like to do it too.”

He and his fishing co-operative colleagues each catch an average of 35 kilograms of carp and mojara each day — half the amount captured in the past. They usually harvest immature fish and sometimes charales, a finger-sized species that thrives in the lake’s warm, high-nutrient waters. A father of six himself, Loza’s eldest son saw no future in the lake and decided against fishing.

Located 40 km south of Guadalajara in western Mexico, the massive lake, referred to as Mexico’s inland sea, once supported a thriving fishery. Lake Chapala had receded over the past two decades to a mere 12 per cent of its original volume by 2003. Water management squabbles, poor agricultural practices and rapid population growth starved the lake of its inflow and withdrew much of what remained. Industrial waste, agricultural runoff and sewage contaminates the trickle of water that reaches Lake Chapala from its primary tributary, the Lerma River. Due to an unusually rainy season last year, the lake swelled to 40 per cent capacity, but it still remains imperiled and highly polluted.

With few barriers to entry, no system of licensing and weak property rights, fishers from 60 co-operatives pursue a dwindling supply of fish in Lake Chapala. The Mexican environment ministry (SEMARNAT) estimated the Lake Chapala catch decreased by 50 per cent during the 1990s.

“(It’s a) tragedy of the commons,” said Brian Murphy, a biologist at Virginia Tech in Blacksburg, Va., who studies lakes and fisheries around the globe, referring to a theory that inherent common property will be abused by the worst elements of a community. “In virtually all of the developing world, inland lakes like [Chapala] are over-fished.”

The severity of Lake Chapala’s problems with over-fishing, water quality and quantity emphasize Murphy’s opinion when compared to other troubled bodies of water. “SEMARNAT isn’t even monitoring the system completely, much less enforcing regulations,” he added. “I don’t know another [lake] that has all three [problems],” he remarked.

The water level is the most important issue for Lake Chapala, said Manuel Guzman, a water expert at the University of Guadalajara. More water evaporates off Chapala, a naturally shallow lake, than it currently receives in inflows. The low water levels have concentrated pollutants in the lake and increased its temperature and evaporation. Sediment created by development and deforestation have also decreased the lake’s depth and destroyed fish habitat.

Besides harming the fishery, the low water level and pollution have hurt the local tourism industry and diminished property values. The tourism business and property values near Lake Chapala fluctuate with the water level, which crests just shy of Chapala’s pier. Until recently, boat operators bussed passengers almost two kilometers across the dry lakebed from the pier to shoreline. Business roared back after last fall’s rainy season, jumping 400 per cent, according to government statistics. “The tourists stop coming when the lake dries up,” said Arturo Gutierrez, the mayor of Chapala, the largest community on Lake Chapala’s northern shore. “Thanks to the lake, we have one of the best climates in the world.”

A popular day trip from Guadalajara, the lake’s perpetual spring-like climate and spectacular scenery have long attracted an eclectic collection of artists, tourists and villains including former Mexican dictator Porfirio Diaz and writer D.H. Lawrence. A colony of 12,000 American and Canadian retirees populates Chapala and Ajijic, the north shore’s two biggest cities.

Besides harming the local area, the shrinking lake also threatens the water supply of nearby Guadalajara, which obtains 65 per cent of its water from Lake Chapala. The Jalisco capital has mushroomed over the last 25 years to a population of five million. Its waterworks loses approximately 40 per cent of the water through leaky pipes. An Organisation for Economic C0-operation and Development report found municipalities across Mexico waste 44 per cent of their drinking water.

Clandestine pipes also illegally siphon off some of the water extracted from Lake Chapala. Thieves extract treated water through illicit connections to irrigate crops, gardens and ranches. The Informador newspaper reported in 2001 that one pipe alone withdrew 1,200 litres of water per second.

Across Mexico, governments of all levels subsidize municipal water. It costs SIAPA, the local water supplier in Guadalajara, 4.77 pesos to treat and deliver one cubic meter of water (1,000 litres), but it charges an average of 1.50 pesos per cubic meter. Chapala charges each household a mere 300 pesos per year for water. Water users in Jalisco use 270 litres per day, 80 per cent more than the French average and double the amount used in Israel.

Furthermore, SIAPA recently forgave 75 per cent of its overdue water bills, worsening its revenue problem. Mexican politicians routinely promise cheap water during election campaigns and nationwide only 60 percent of water bills get paid.

Mexico City, Agauscalientes and Cancun recently privatized portions of their water systems to reduce waste and attract infrastructure investment. The four private companies hired in Mexico City recently installed meters to encourage conservation and set about fixing pipes to stem financial losses. While Guadalajara’s needs put stress on Lake Chapala, Mayor Gutierrez points upstream towards the dry highlands of Central Mexico to the source of the Lerma River, which feeds Lake Chapala.

The Lerma River originates just west of Mexico City in Mexico state. It flows for 750 km through five states and the nation’s industrial and agricultural heartland before emptying into Lake Chapala. Although home to 75 per cent of the Mexican population and 70 per cent of its irrigated land and industrial output, central Mexico receives just 25 per cent of the nation’s rainfall.

Near Lerma River’s source, Mexico City pumps water from the river back over the continental divide for two million of its residents. As the river descends from its source, many large and small cities dump raw sewage into the river and industrial users, including chemical plants and a Pemex refinery, discharge untreated waste water into the river.

The Mexican constitution guarantees access to water and forbids private ownership of the resource. New laws enacted in 1992 introduced water rights, irrigation councils and an improved National Water Commission (CNA) to oversee water use issues and limited private sector involvement in municipal water systems. The CNA still charges little for concessions to the Lerma River and provides few incentives to conserve water.

Concessions to the Lerma River sell for as little as $30 per year per hectare. Small farmers inefficiently flood their land and cheap prices dissuade large farmers from improving irrigation techniques. An OECD study found poor methods waste 54 per cent of irrigation water. Large farms in the basin grow water-intensive crops such as strawberries for export to the United States, but pay the same fee as tiny ejidos (collective farms frequently created from expropriated haciendas).

The water table in Guanajuato sinks an average of 1.8 to 3.3 metres per year and 70 per cent of its aquifers are over-exploited. While agriculture uses 70 per cent of the Lerma River’s water, it contributes much less to the national economy than other industries. Victor Lichtinger, a former advisor to President Vicente Fox, advocated the government cut its irrigation subsidies in 2001, but acknowledged such a move would be unpopular. The family of President Fox prospered by ranching and cultivating winter vegetables in Guanajuato.

By the time the Lerma reaches Lake Chapala, only a trickle remains. The small amount that enters the lake is loaded with pesticides, sewage and heavy metals. The nitrogen-rich water spawns vegetation in the lake, which clogs its shallow waters.

With the lake declining, politicians have proposed constructing a massive dam on the Santiago River, which empties Lake Chapala, to supply Guadalajara with drinking water. The scheme would dam the river in a canyon north of the city slightly downstream from the convergence point of the Green River, which originates to the north.

“The Santiago River is highly contaminated,” said Rosier Omar Rodriguez, a water expert at the University of Guadalajara who opposes the dam. The dam would trap dirty water, contaminated with Chapala’s filth and untreated sewage from Guadalajara. Planned for a site lower than the city, the hydroelectricity the dam generates would be used for pumping the water uphill to purification plants.

Rodriguez instead proposed a series of dams for the Green River, which he said flows three times faster and is cleaner. Local politicians rejected it out of hand. He also pointed out the dam would bridge the canyon and thus quicken development plans for the side opposite Guadalajara possible - thus enriching the project's proponents even further.

Despite continued threats to the lake, Justus Hauser, a member of Amigos de Lago and nine-year Chapala-area resident, feels more optimistic than ever about the lake’s recovery prospect. The World Fund for Nature recognized Chapala as a lake in peril and Hauser said the increased international attention will put pressure on politicians to give the lake its fair share of water. For the first time in years, water filled the Chapala in 2003 as the excess spillover from the upstream dams filled the lake instead of being hoarded.

This story appeared in The Reflector.