GNF - Threatened Lake of the Year 2004
 

Threatened Lake of the Year 2004: Lake Chapala in Mexico

 

Over many years Lake Chapala has suffered severe water loss. In the past, the lake’s volume was twice the size of Lake Constance. It has lost about three-quarters of its volume. From villages which once were located at the edge of the lake, you can hardly see the lake today. Irresponsible use of water, corruption and a profit seeking mentality have almost completely destroyed this drinking water reservoir for 6 million people. A huge dam project is planned to provide water for the people who depend on Lake Chapala as drinking water reservoir. This project is economically absurd, unsocial and an ecological disaster. Some 3,000 local fishermen are threatened with commercial ruin, fish species such as "popoche" which used to be very common is almost extinct due to lack of water and DDT presence in the water.

In the past, in Central Mexico, diverse smaller lakes and wetlands were drained. Lake Chapala is one of the last remaining refuge for rare animal and plant species. About 80 bird species among them Yellow Robin, Snowy Egret, Great Egret, and up to 3,000 American White Pelican rest or winter in this unique lake region. Lake Chapala is a traditional stop over for over 2 million water fowl on their annual migration.

 

The Mexican project partners have worked out an action plan to save the lake. The Living Lakes network is striving for

  • the preservation of Lake Chapala as drinking water reservoir
  • the protection of migrant and breeding birds
  • the designation of Lake Chapala area as Ramsar reserve.

Lake Chapala’s situation is critical. Due to heavy rainfall in autumn 2003, the lake volume has increased and currently amounts to more than 4 billion cubic meters, a few months ago the volume was 1,6 billion only.

These unusual heavy rainfalls, however, cannot conceal the fact that the necessary water inflow of River Lerma tends to zero and the natural capacity of the lake (8 billion cubic meters) is a distant prospect. The Lerma water quota allocated to the users directly depends on the amount of precipitations.

 

The small amount of Lerma water entering the lake is highly polluted by untreated waste water from households, industrial sewage as well as fertilizers in form of nitrates and phosphates from agriculture. The University of Guadalajara ascertained high heavy metal concentrations (amalgam, copper, iron), even DDT residues. The DDT concentration lies between 0.02 and 3.4 mg/l and exceeds the maximum value allowed 3,400 times (0.001 mg/l). Lake Chapala is the most important supplier of drinking water for the city of Guadalajara. The water is pumped to Guadalajara and inadequately purified water is released to Guadalajara. Illegal water withdrawals for agricultural and domestic purposes reduce the amount of water available.

Not only the local people are threatened, also the concentration of toxic substances in the water is alarming. Fish catches have greatly diminished, the average income is less than 50 Pesos (less than 4 Euro) per day. The water pollution threatens also water fowl, especially the fish-eating White Pelican which winters along Lake Chapala. The government is owner of the desiccated areas (zona federal) and assigns concessions for their use. In fact, only temporary agricultural use is allowed, but many farmers have fenced the allocated areas. Additionally illegal constructions, walls, golf courses were built. There is a great danger that large parts of the lake which belongs to the state of Michoacan will be completely drained. 

According to calculations of the University of Guadalajara and the Fundación Cuenca Lerma Chapala, the lake could completely disappear when the water of the exceptional heavy rainfall of the past year will be used up and if there is no increase of in-flowing water.
 
The reasons for the continuing destruction of the lake are diverse:
  • There is no political volition of the national government to improve the lake’s situation. President Vincente Fox comes from the state of Guanajuato where the irrigated agricultural area has substantially increased. As he is not interested in upsetting "his" farmers, no steps to save the lake were undertaken so far although according to the national Water Regulations (Ley Nacional de Aguas) the President is the ultimate authority in view of all water-related questions. Environment Secretary Victor Lichinger (Secretaria de Protección al Medio Ambiente y Recursos Naturales) supported the restoration measures and had worked out a "Master Plan" (Plan Maestro) to save the lake. This plan failed because of the non-approval of his own government and the state of Jalisco. Shortly after Lichtinger’s declaration that the Arecediano Dam project has not yet been accepted by his authority, President Fox dismissed his Environmental Minister and appointed Alberto Cardenas Jimenez, ex-governor of Jalisco as new Environment Secretary.
  • Lake Chapala is "managed" like a storage lake by the national water authorities. In 2003, thanks to heavy rainfalls the decreed water quota of 4,500 cubic metres defined by the Consejo Nacional was reached (representing about half of the natural lake volume), the danger of dessication however prevails, if there is no constant influx of water into Lake Chapala.
  • Enormously increased water abstractions for agriculture in the state of Guanajuato (upper reaches of River Lerma) due to the extension of the irrigated agricultural land to 520,000 hectares and due to a completely out of date irrigation infrastructure, 11 retention dams, illegal water withdrawals and well drillings.
  • During the past 30 years, the population of Guadalajara has increased from one to five, six millions (the exact number is not known). Consequently the demand of water and food mainly coming from Guanajuato increased enormously.
  • Since 1994, the state of Jalisco is aiming to drain 38,900 hectares lake surface for agricultural and urbanisation purposes.

The authorities pretend that Lake Chapala cannot cover the current water demand of Gudalajara. This is also the most important reason for the huge Arcediano dam project (with a capacity of 350 million cubic metres) initiated by the state of Jalisco, northeast of Guadalajara. It is planned to construct the dam at the mouth of Rio Verde into Rio Santiago, exactly on the spot where untreated wastewater of the metropolis of Guadalajara (about 6 million people) enters River Santiago. The necessary purification of the sewage would be extremely expensive. The construction costs of the dam are estimated at 30 billion Pesos ( = 2,23 billion Euro). The state of Jalisco is very interested in realising this project. Real estate speculations certainly play an important part in this development. If Lake Chapala contained as much water as in earlier times, then the water supply for Guadalajara would be sufficient and the dam superfluous.   

If only a fractional amount of the money needed for the construction of the dam would be used to repair defective pipes in Guadalajara (about 50 % of the water is wasted due to leakage loss), Lake Chapala could easily cover the water demand. And if additional funds would be provided to modernise the agricultural irrigation system (especially in Guanajuato), the future of Lake Chapala would be secured.

Therefore an action plan was set up and signed by members of the Sociedad Amigos del Lago de Chapala and of the Fundación Cuenca-Lerma-Lago Chapala-Santiago A.C. as well as by Dr. José Antonio Gómez Reyna on behalf of committed scientists of the University of Guadalajara.

 

The common vision

Restoration of the natural volume of 8 billion cubic metres of Lake Chapala.

 

The Mission

  • To create the legal, technical and social conditions for the restoration of Lake Chapala
  • Implementation of all measures which are necessary to restore the lake
  • Promotion of sustainable development to preserve the ecological, cultural and social values of Lake Chapala to fulfil its functions durably.