The World Bank/WBIs CBNRM Initiative

Case Received: February 7, 1998

Author: Evelyn Irene Reyna

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Integrated Management of the Lake Amatitlan Basin:

Authority for the Sustainable Management of Lake Amatitlan and its Basin

High concentration of population in the area, heavy exploitation of natural resources, shortage of water; all components of a sorry process: the deterioration of Lake Amatitlán and its tributary watersheds. The lake is today in imminent peril of becoming lost as a resource and as a national heritage.

Lake Amatitlán is one of the lakes with the longest ties to human history in the world. There are archeological remains around it dating back to the year 2000 B.C., while jade, bone and clay artifacts of great historical value have been retrieved from its depths. The town of Amatitlán was founded in 1536 and quickly developed into a major center on account of the fertility of the surrounding land.

Today, however, Lake Amatitlán is moving toward a bleak future. Studies made by the Authority for the Sustainable Management of Lake Amatitlán and its Basin (AMSA), a government institution, confirm that in 1800 the lake's average depth was 33 meters; by 1996 this depth was down to 18 meters, and by the year 2016, if no rescue actions are undertaken it will be no more than a murky 7 1/2 meters.

The question on everyone's lips is the same: where is all the pollution coming from? Probably everybody has their own theory, but one thing is sure, they all blame the industrialization of the area. However, the actual causes are varied.

To begin with, of the 24 sewage-treatment plants in the basin, not a single one is working right now! Almost 23% of Guatemala's industries are located in the Amatitlán basin and only 1% of these have effluent pretreatment systems. A large part of the nontoxic industrial wastes such as zinc, oils and coloring matters that are discharged into the lake remain in suspension on or near the surface.

One incredible fact is that the Villalobos River brings around 500,000 tons of sediment down into the lake, causing it to lose 70 cm of depth each year.

The causes of the degradation process Lake Amatitlán is undergoing are simultaneously industrial, demographic and geographic. One of them is the outcome of erosion which brings a loss of water-retention capacity. Eutrophication is also increasing from year to year. Eutrophication is a process that occurs when a body of water receives a nutrient overload that causes degradation of the aquatic ecosystems, characterized by increased growth of algae and plants. This situation is due mainly to the demographic growth of Guatemala City and of other nearby cities, indiscriminate exploitation of the water and the growing number of industries in the area.

The reason for the exploitation of the underground water of the basin and the lake is that this is the zone of greatest permeability, i.e. the zone with the most underground water.

The deterioration of Lake Amatitlán goes beyond being a matter of purely ecological concern; one of the most important factors involved is shortage if water.

The lack of employment opportunities in the rest of the country obliges the rural population to move into Guatemala City and the surrounding area in search of better-paying jobs. The low-income neighborhoods are growing in a totally unplanned fashion and the basic services are unable to keep up with the expansion. Because of the circumstances and the existing infrastructure this growth has taken place in a southward direction, out toward Lake Amatitlán. However, the unplanned urban growth causes the lake to lose some of its capacity to absorb and contain water. The excessive concentration of population in the basin calls for a matching concentration of services that the authorities do not have the means to provide.

It is calculated that EMAGUA, the water authority, extracts at least 35% of the water it supplies to the capital from the basin, while the nearby towns of Villa Nueva, Via Canales and Petapa obtain their supplies from its underground water. An essential point to be noted is that the lake's water shortfall is today 3 m3 per second, and by the year 2000 it will be 5 m3 per second.

There has been a disturbing change in the aquatic life. Fish such as the mojarra and pepesca have disappeared, and others like the pompano, tilapia and carp have been introduced. Photosynthesis capacity as been severely reduced by the large quantities of solids in suspension and microorganisms on the surface. Each year, 75,000 tons of solid wastes in suspension is carried into the lake!

The presence of other organisms and wastes on the surface blocks the sun's rays from penetrating and the presence of oxygen-consuming bacteria prevents life in the lake.

However, the domestic and other wastes discharged by the surrounding communities, the chalets, villages, public beaches and businesses, are all playing a devastating role.

For these reasons, recent studies give the lake a remaining lifetime of 20 years if the pollution is not curbed.

It was to check and turn back this deterioration and to decontaminate the damaged ecosystem that AMSA--the Authority for the Sustainable Management of Lake Amatitlán and its Basin--was established. With the backing of the present government, AMSA's purpose is to manage the use of the resources and strengthen the actions undertaken to protect and rehabilitate the lake and thereby enable the population to live in a wholesome environment.

AMSA has submitted a plan for the Integrated Management of the Basin and Lake of Amatitlán, which includes measures to balance the undeveloped and overpopulated areas and provide the population with an environment suitable for human activity.

The environmental control plan developed by AMSA comprises municipal sewage-treatments, a waste-water control system; drainage systems in the urban areas and community participation through the Environmental Education and Citizen Awareness project.

A key objective is control of solid and liquid wastes to lessen pollution. One way of strengthening compliance with the rules and standards set for protecting the lake is to oblige industries to install liquid and solid-waste pretreatment systems. Liquid wastes will be disposed of by means of treatment systems at sewage discharge points and it is expected that these systems will be able to generate profits that will make them self-managing without any need for subsidies.

Household solid waste will also be managed with treatment systems, in which community and private-sector involvement will be promoted, with the possibility of reuse of the resulting treated or recycled byproducts.

In the medium term a main sewage-treatment plant will be built on the Villalobos River, to handle all waste water from the zone.

To restore the degraded areas, AMSA plans to carry out reforestation, which has already been started, with the sowing of 30,000 trees of different species native to the area and appropriate for the type of soil and climate and, in particular, the needs of the population. An input bank has also been set up for improving the basin's environment.

The environmental control program is another of the tools for rescuing the lake and sets out the conditions for analyzing and studying it. A program has been established for monitoring the quality of the water in the lake and the rivers that flow into it; it is hoped to bring the meteorological and hydrometric stations back into use so as to obtain the fullest and clearest analysis possible of the pollution of the lake.

In its vision for protecting Lake Amatitlán, AMSA sees the lake being used primarily as a water source and also for tourism, sports, recreational and cultural purposes.

The aim of the Environmental Education program is to coordinate the efforts of the population at large. AMSA plans educational activities to foster preservation of the lake, to complement the programs to be carried out in the schools with the support of the Education Ministry and of the population in general.

To this end photographic contests and drawing competitions for school-age youngsters have already been run with a view to drawing a response from the population and focusing their interest on the lake and its ecosystem and encouraging theme to express their vision of what needs to be done and the hoped-for outcomes. This will reflect a clear and active participation in the preservation of our lake.


The task ahead of us is a difficult and costly one, but above all it is an urgent one.

The support of the local authorities, of private enterprise and of the population at large is needed to protect a future reserve of water for the metropolitan area.

AMSA's work will soon begin to bear fruit, and the benefits will be for everybody. For those who live in the nearby areas, there will be more and better public services, substantial improvements in agricultural production, surface and underground water of optimum quality and sufficient to supply all needs; and finally, but most important of all, an ecological equilibrium and a good climate for the inhabitants.