The Jalisco Water Commission (CEA) has emitted a gloomy forecast for Lake Chapala, predicting that it will shrivel over the next two years until the water level plunges to close to the record low marks of 1955 and 2002.
CEA Director Felipe Tito Lugo has said that the lake is already in a critical phase, maintaining a steady decline because the amount of water lost during recent dry seasons has consistently exceeded the rate of recuperation in summer months. He indicates that Guadalajara’s water supply will be in serious jeopardy by 2016 if the trend continues.
Lake conditions have been monitored since 1900. The most troubling period since then was the decade of 1945 to 1955 when it dropped from 75 percent of its total capacity to less than 10 percent, the lowest level on record.
The 1955 rainy season greatly replenished the lake, putting it back above half full. During the dry season of 1958 it dropped back to a fifth of its capacity, but good rains that year brought it back to 70 percent.Another big drop in 1991 left Chapala at 20 percent capacity. Its second major crisis occurred in 2002 when it fell to just 11 percent. Huge recovery came with the heavy rains in 2003 and 2004.
Over the past 20 years the annual rate of decline has ranged from 69 centimeters to as much as 1.45 meters. Each year the lake loses about 1.30 meters due to evaporation and another 20 centimeters from extraction for the Guadalajara metro area’s water supply.
Six out ten metro area residents depend on water pumped from Lake Chapala. Average per person consumption is 200 liters per day, double the amount recommended by UNESCO.
At the height of the dry season the level of the lake drops by one centimeter per day. Each centimeter in descent is roughly equivalent to a loss of 10 million cubic meters of water. One cubic meter is equal to 1,000 liters.
University of Guadalajara scientist Arturo Curiel Ballesteros stresses that the true reason for the pending crisis is that the lake does not receive sufficient influx from its main source, the Lerma River, to compensate for the demands of human and natural consumption.
“The previous crisis (in the 1950s) was due to a meteorological drought provoked by recurrent climatic conditions in an era when demand was not so severe. What is happening now is a drought induced by all of the users.”
The lake currently stands at about 40 percent of its capacity. So far it has lost about half of the 97 centimeters gained during last year’s rainy season. Fortunately the rate of decline has actually been considerably less drastic than last year thanks to the favorable impact of hurricanes Ingrid and Manuel last fall.