Ilopan Classification Essay

Roundtable I - Management of Aquatic Ecosystems

Background Paper: Management of Aquatic Ecosystems
Background Paper: The Environmental Conditions in Latin America - A Brief Overview
Sub-track: Environmental Problems and Assessment
Sub-track: Protection and Restoration Strategies


Joseph B. Browder, Partner, Dunlap & Browder, Inc., Washington, D.C., USA

Dr. Emiko Kawakami de Resende, Secretary of the Environment, State of Mato Grosso do Sul, Brazil


Sub-Track: Environmental Problems and Assessment

Dr. Thomas Lodge, Principal Environmental Scientist, Law Environmental, Inc., Fort Lauderdale, Florida, USA

Miguel Monserrat, National Director of Water Pollution Control, Water and Environment Advisor, Secretary of the Presidency, Argentina

Sub-Track: Protection and Restoration Strategies
John Kusler, Executive Director, Association of State Wetlands Manager, Berne, New York, USA

Dr. Gonzalo Castro, Executive Director, Wetlands for the Americas, Manomet, Massachusetts, USA

Dr. Jorge A. Marban, Senior Professional, Department of Planning, South Florida Water Management District, West Palm Beach, Florida, USA
Background Papers
Management of Aquatic Ecosystems, by Joseph Browder, Dunlap and Browder, Washington, DC, USA

The Environmental Conditions in Latin America - A Brief Overview, by Jaime Incer, Minister of Environment and Natural Resources, Managua, Nicaragua

Papers and Authors

Sub-Track: Environmental Problems and Assessment

1. Nutrient and Sediment Retention in Andrew Raised-Field Agriculture, by Heath J. Carney, Ph.D., Research Associate, Division of Environmental Studies, University of California, USA

2. Environmental Assessment and Restoration Planning for Sensitive Coastal Resources in Isla Vieques, Puerto Rico, by Gerard A. Gallagher, III, Geographer, Assistant Regional Manager, ecology & environment, inc., Tallahassee, Florida USA

3. Adaptively Assessing and Communicating Complex Resources Issues, by Lance G. Gunderson, Department of Zoology, University of Florida, USA

4. Environmentally Compatible Watershed Management in Venezuela, by Freddy Hermoso, General Director, National Service of Basin Conservation, Ministry of the Environment and Renewable Natural Resources, Venezuela

5. Lake Chapala and Rio Blanco: Two Cases of Environmental Problems in Western México, by Fernando Montes de Oca, Executive Director, Fundacion Chapala, Guadalajara, México

6. Environmental Sustainability and the Role of Stewardship, by D. W. Moody and E. T. Smith, U.S. Geological Survey, Reston, Virginia, USA

7. Washington State Marine Waters Environmental Program: A Practical Use of Environmental Assessment Science, by Maria Victoria Peeler, Supervisor, Permit Coordination Unit, Department of Ecology, State of Washington-Environmental Review and Sediment Management Section, Olympia, Washington, USA

8. Aquatic Weed Control in the Yarinacocha Pucallpa Lagoon, by Olga Rios Del Aguila, Regional Agricultural Director, Pucallpa, Ucayali, Perú

Sub-Track: Protection and Restoration Strategies

9. The Role of Non-Governmental Organizations in Environmental Assessment in the Pantanal Region, by Joaquim Rondon Rocha Azevedo, Executive Director, Sociedade de Defesa do Pantanal (SODEPAN), Campo Grande, MS, Brazil

10. Conserving Aquatic Ecosystems for Sustainable Development, by Gonzalo Castro, Executive Director, Wetlands for the Americas, Manomet, Massachussetts, USA

11. Management of Aquatic Ecosystems - The Pantanal Case, by Agostinho Carlos Catella, Researcher, Empresa Brasileira de Pesquisa Agropecuária - Centro de Pesquisa Agropecuária do Pantanal (EMBRAPA/CPAP), Corumbá, MS, Brazil

12. The Everglades Nutrient Removal Project, by Mariano Guardo, Senior Civil Engineer, Research-Everglades System Research Division, SFWMD, West Palm Beach, Florida, USA

13. Lessons Learned from Five Decades of Wetlands Restoration and Creation in North America, by Robin Lewis, President, Lewis Environmental Services, Inc., Tampa, Florida, USA

14. The Role of Wetland Filters in Ecosystem Restoration, by David L. Stites, Supervising Environmental Specialist, St. Johns River Water Management District, Palatka, Florida, USA

15. Development of the Kissimmee River Restoration Plan: Lessons Learned and Recommendations for Comprehensive Restoration Projects, by Louis A. Toth, Senior Environmental Scientist, Division of Kissimmee & Okeechobee Systems Research, South Florida Water Management District, West Palm Beach, Florida, USA

Background Paper: Management of Aquatic Ecosystems

Joseph B. Browder1

1 Partner, Dunlap & Browder, Inc., 418 10th Street, SE, Washington, DC 20003-2133, USA
A Background Paper prepared for discussion in the Roundtable I: Management of Aquatic Ecosystems

Water brings us together as neighbors, cultures and communities on Earth, and binds us to the rest of nature. Conflicts about water divide us, and lead us to degrade nature and ourselves.

This gathering presents us with a challenge: to search for ways to help each other reconcile the management of water for human health and commerce with the management of water for the protection of nature. We do so out of respect for the diversity and mystery of the natural wold, and from the certain knowledge that nature and humankind inevitably bear the wounds of each other's neglect.

The urgency of this reconciliation stems from immediate public health, water supply and economic development needs in much of the world, and from our increased understanding that even small changes in the water regimes of natural systems can cause profound and costly damage, to nature and to society.

Today's resource management decisions are more complicated because water, as an asset that flows through the global economy, is now subject to more sophisticated social and political inputs. For decades, the world-wide reach of capital and engineering have changed little-known mountain streams on small tropical islands, and re-made some of the Earth's largest rivers and estuaries. Now, local environmental protection campaigns, integrated with local economic and cultural interests, are capable of global outreach to change the plans of capital and engineering. Only recently have scientists and citizens throughout much of the world developed communications to link local critics of resource development projects with international groups able to influence the financing and design of water projects and other major infrastructure development and resource management programs. As a result, local interests that have felt disenfranchised from decisions about water resources now enjoy opportunities to use global resources to achieve more political influence in their own communities.

Major changes in a natural water regime often redistribute economic benefits away from those local communities which, however imperfectly when measured against the ambitions of regional or national enterprises, have accommodated to the natural system. For example, local fishing communities economically damaged by water management programs that increase benefits to other enterprises richer in both political and financial capital are, in isolation, sometimes treated as marginal assets, to be written off in the search for higher yielding activities. But today the concept of the global village is becoming reality. When the integrity of a specific local economy can be linked to the integrity of a natural system, formerly marginalized interests can establish influential global relations with scientists, non-governmental organizations, multi-lateral agencies, and other institutions capable of modifying or even halting proposed water resource projects and other development programs.

For many local interests, the advocacy of environmental responsibility has thus become an instrument for more general participation in politics. Where people feel stronger kinship in defense of a forest or river than in yielding to the advice of a province or state, when government response may seem less meaningful than the responsiveness of peoples from different cultures who share similar interests in the protection of nature, a new political economy is evolving. In a world where our nation-states are learning to live with the benefits and difficulties of multi-national investments and multi-lateral organizations, we should not be surprised at the emergency of global citizens.

For the professional women and men who, from every perspective, seek to understand and better administer our relations with natural resources, this challenging new policy environment offers great opportunity. Much conflict about water resources development is based on concern about nature, but also relates to the needs of people. Productive, sustainable local social and economic activities based on less capital intensive use of natural resources are sometimes incorrectly dismissed as without value in a national balance sheet. We frequently look at today's needs and limitations, and rationalize natural resources damage that will cause lost opportunity and higher costs for our children. Yet those whose principle interest is the preservation of natural systems are equally capable of marginalizing and rationalizing. Agony and disease caused by contaminated community water supplies, loss of soils, water and wildlife to destructive farming methods that appear to be the only economy for many, rural peoples, and cities throughout the world without the social structure to provide water, sanitation, shelter and food to millions of men, women and children, represent environmental crises as real as the threatened loss of a species or an ecosystem.

Precisely because more people can speak and be heard, more of us can learn, from each other and from the world outside our professional circles. It has become pointless to think of protecting the Earth's great resources without planning to deal with the demands of human settlement and economic development. It is equally futile to think of using water, or any other natural resource, without planning to protect the ability of ecosystems and biological resources to renew and sustain themselves.

This does not mean there will be no winners and losers. Resources of great economic value will remain undeveloped, to preserve unique and irreplaceable wild places and creatures, or will be less than fully exploited in order to protect the interests of local communities. In other cases, species, biological communities and human cultures will be lost forever to satisfy economic demands. But we are capable of making even those choices with greater wisdom, and are more capable of finding ways to keep humanity living in a living Earth. When water resource managers learn enough about the social and economic values of natural systems, science and engineering will better reveal to us the opportunities for meeting human needs while protecting nature.

When defenders of nature learn enough about the ways in which water flows through our economy, environmental science and engineering will participate more effectively in decisions that, in the end, are made by economically organized human societies.

If this mutual understanding is accompanied by commitment to respect the legitimacy and urgency of both missions, we can, in ways small and large, personal and institutional, help discover the real meaning of sustainable development, for our human communities and for the natural world that nourishes us all.

Background Paper: The Environmental Conditions in Latin America - A Brief Overview

Jaime Incer1

1 Minister of Environment and Natural Resources (MARENA), Apartado Postal 5123, Managua, Nicaragua
A Background Paper prepared for discussion in the Roundtable I: Management of Aquatic Ecosystems

The intensive use of the natural resources in Latin America has resulted in an undesirable transformation of the aquatic ecosystems in the region. It can be said that this transformation started when the early civilizations started using fire, plants, and animals for their preservation and survival. The impact on the environment became more severe with the advent of the Industrial Revolution and the intensification of agricultural production.

It is important to point out that the abuse of the natural resources is not a natural consequence of the human process, but rather a consequence of the models of economic growth, poorly chosen in the past, which have not taken into consideration the concept of ecological sustainability.

There are a number of issues that contribute to the reduction of natural resources in the hemisphere. The most significant ones are:

Intensive use of the land
Environmental impact of human settlements
Utilization of fresh water and coastal resources
Continuous deforestation
Exploitation of mineral resources
Increasing need for energy related
Industrial development
Lost of biodiversity
Intensive Use of Land: This is a very serious problem throughout Latin America. The intensive use of land in many areas has produced a high degree of erosion, salinization and alkalinization of soils and decertification. Erosion has reduced the amount of usable land by 30% in Central America and 10% in South America. About 70% of the productive arid lands in South America and Mexico have been through some type of decertification. Latin America has between 693 and 736 million of hectares of potentially cultivated lands.

Environmental Impact of Human Settlements: The majority of the Latin American nations have urbanized quite rapidly during the last half of the century.

The main problems caused by the rapid urbanization of major cities in Latin American such as Rio de Janeiro, Buenos Aires, Quito, Mexico City, Guayaquil, Managua, Guatemala City, Tegucigalpa, La Paz, Medellin and others have caused domestic and industrial contamination of lakes, rivers and coastal environments which have affected public health and sanitation.

Utilization of Fresh Water and Coastal Resources: The contamination of aquatic ecosystems throughout Latin America has significantly reduced the value of natural resources throughout this hemisphere. Important resources such as Lake Amatitlan (Guatemala), Lake Ilopango (El Salvador), Lake Managua (Nicaragua), Yohoa Reservoir (Honduras), Panama Bay (Panama), Lake Valencia (Venezuela), Rio La Plata (Argentina), Habana Bay (Cuba), Bluefield Bay (Nicaragua), Tarcoles River (Costa Rica), Choluteca River (Honduras), Amazonas and Orinoco River, and San Juan River (Nicaragua), among others, have been impacted by the industrial, agricultural and urban development.

Latin America can potentially produce 22% of the world hydroelectric energy but only 22% of the energy consumed in Latin America is of hydroelectric origin. There are several major waterways that contribute to economic development in Latin America but it also represents a threat to the natural resources of the region. The Amazonas River, the Parana and La Plata Rivers and the Apure/Orinoco system are important elements of the economy of South America. The planning and management of the water resources should be a basic activity in the promotion of sustainable development in the region.

Continuous Deforestation: The problem of deforestation in Latin America is very serious. It is estimated that deforestation have been responsible for 40% of the CO2 emissions in the region. Brazil (20%), Columbia 7%, Peru and Ecuador (3%), and Mexico (2%) are the most impacted countries in the region.

The burning of tropical forests have serious ecological consequences both at the local, regional and global scale. In Latin America 80 million people use firewood for cooking purposes with an annual per capita consumption of 350 to 370 kilograms. This implies a significant degree of deforestation.

Other ecological consequences attributed to deforestation are high use of biomass, increased soil erosion, lack of groundwater recharge, atmospheric contamination and global warming.

Exploitation of Mineral Resources: The mineral extraction in Latin America is very intensive and is closely associated with some of the environmental problems in the region, particularly air and water contamination and destruction of habitats adjacent to the mines and processing plants. Lack of treatment of the effluents that are discharged from the mineral processing plants results in water contamination of chemical deviating of sulfur. A typical case of degradation occurs in the Amazon jungle with the exploitation of gold and diamonds which contribute significant concentrations of mercury to the rivers of the region. A similar situation exists in the jungles of the Orinoco region. The countries more affected are those near the Andes Mountains such as Chile and Peru. Among the rivers more affected by mineral activities are the Mantaro and Rimac rivers of Peru and the Mico River of Nicaragua.

Increasing Use of Energy Related Resources: The production transfer and use of energy have produced negative and positive effects in the quality of life in Latin America The principal environmental impacts due to energy production and use in Latin America are: extension of valuable tropical ecosystems, air and water contamination related with transport of energy related products such as petroleum, sedimentation and erosion of river basins, thermal contamination of water, increased deforestation due to the use of firewood and local climate changes. The most important sources were petroleum and natural gas (17.1%), hydroelectric energy (13.6%) and biomass (12.4%). Others in minor scale are coal, geothermic energy and nuclear energy.

Past experiences have shown that the reservoirs required for energy production have produced ecological changes that should be taken in consideration in future development of hydroelectric projects. The use of non-conventional systems such as biomass, wind and solar energy is very limited and should be expanded. Energy conservation efforts should be promoted.

Industrial Development: Industrial development as well as the use of mineral and energy related resources have provided significant impact to the environment particularly to the aquatic ecosystems. Chemical contamination of lakes, rivers, estuaries, and wetlands prevails in most countries of Latin America and Caribbean islands.

The main industries that have contributed to water and air pollution are the food, chemical and health industries, and petroleum and gas refineries. Air pollution caused by industrial plants and the transportation industry have produced significant health problems in many important cities of the region such as Mexico, Rio de Janeiro and many others.

It is estimated that in Latin America 41,000 tons of toxic residues are produced every day without adequate treatment facilities. These products are responsible for numerous diseases and deaths.

In the cotton region of Central America, the extensive use of insecticides has reached 80 kilograms per hectare. Frequently, the products employed as herbicides, insecticides and pesticides have been prohibited in the developed countries. About 75% of these products have been prohibited in the United States of America. During 1986 and 1987, 27% of the deaths in El Salvador were caused by intoxication from pesticides. According to a Greenpeace report, more than 2000 kilograms of products prohibited in the United States arrived in Central America every day. In the industrial city of Cubato in Brazil, 40 of every 1000 children were born dead in 1980 and 40 others were deformed due to severe industrial waste and pollution.

These are opportunities for industries in the Latin American region to become more environmentally aware, by using environmentally acceptable materials, developing pollution free processes, cleaning gas and liquid effluents prior to discharging to the receiving bodies, and by the use of recycling whenever is feasible. All these measures can be done in an economically efficient basis.

The lack of government controls and environmental policies related to industrial development have contributed to a status quo contrary to the principles of sustainable development.

Lost of Biodiversity: The lost of biodiversity due to the effects of unsustainable development has increased significantly in recent years.

Latin America accounts for 90,000 of the 250,000 species of tropical plants in the world. Some of these species are used for medical purposes (10%), for industrial purposes (10%), and for food (15%). In general more than 31,000 species are usable.

Recent projections indicate that 10% or more of the plant species will be extinguished by the year 2000 in the tropical jungles of Latin America.

The fauna of the region, in addition to be very diversified, present opportunities for economic development. Species such as the guano producing seabirds of Chile and Peru, the Vicuna of the Andes region, the Guanaco of Chile and Argentina, the alligator and capybara of the Amazon, Orinoco and Pantanal regions have great economic potential.

The rehabilitation of the impacted ecosystems will benefit the biodiversity of the region and well increase the productions of wood and food related products strategy for sustainable development in Latin America.

The historic role of the region as supplies of materials and resources required to keep high standard of living in the developed nations resulted in overexploitation of the natural resources, thus causing significant degradation of the environment throughout Latin America. Natural resources are depleted or extinguished before they can be regenerated.

The principal factors contributing to the crisis are:

The disorderly growth of the nations in the region

The lack of scientific and technical capabilities

The political and economical instability whatever development strategy is formulated in the future it will need to consider the protection and sustainability of the natural resources of the region. The formulation of aggressive policies of protection of environmentally sensitive areas similar to the one used in national parks, ecological refuges and sanctuaries needs to be considered as priority in order preserve biodiversity in the region.

A series of socio-economic principles needs to be followed in order to promote sustainable development in the region. It is important that a solidarity between society and government be established with multiple participation of non governmental organizations and other interest groups.

It is important to promote:

The sustainable use of natural resource in each county
The use of appropriate technology
A more efficient use of energy
Development of products that satisfy the basic needs of the population
It is imperative that agriculture and industry embrace goals for the improvement of quality of life through specialization, efficiency and productivity. At the same time, it is necessary to reduce production costs in industry and agriculture through the use of more efficient technology, to give special consideration to energy saving technologies, and to promote recycling and re-use of materials and products.

Government and conscious citizens in Latin America must avoid the use of technologies and products banned in developed countries.

The international collaboration in the achievement of sustainable development in Latin America not only can reduce potential tension, but can contribute to a new era of progress in a global scale, that will allow for a superior quality of life. This collaboration will tighten the ties between the north and south nations in a common effort to promote sustainable development and ecological integrity in this hemisphere. This challenge must be met in order to preserve the survival of the human and natural resources in the planet.

Sub-track: Environmental Problems and Assessment

Nutrient and Sediment Retention in Andean Raised-Field Agriculture
Environmental Assessment and Restoration Planning for Sensitive Coastal Resources in Isla Vieques, Puerto Rico
Adaptively Assessing and Communicating Complex Resources Issues
Environmentally Compatible Watershed Management in Venezuela: The Rio Tocuyo Case
Lake Chapala and Rio Blanco: Two Case of Environmental Restoration in Western México
Environmental Sustainability and the Role of Stewardship
Washington State's Marine Waters Environmental Program: A Practical Use of Environmental Assessment Science
Aquatic Weed Control in the Yarinacocha Pucallpa Lagoon

Nutrient and Sediment Retention in Andean Raised-Field Agriculture

Heath J. Carney1, Michael W. Binford², Alan L. Kolata³, Ruben R. Marin4 and Charles R. Goldman1

1Institute of Ecology, Division of Environmental Studies, University of California, Wickson Hall, Office 3134, Davis, CA 95616, U.S.A.; ²Landscape Ecology Group, Graduate School of Design, Harvard University, Cambridge, MA 02138 U.S.A.; ³Department of Anthropology, University of Chicago, Chicago, IL 60637 U.S.A.; 4Instituto de Ecologia, Universidad Mayor de San Andres, La Paz, Bolivia
Note of the Editor: At the time of the publication of these proceedings, only the abstract of the presentation was available. Further details or the complete paper may be available by contacting the author at the specified address.


Raised-field agriculture was widespread throughout Central and South America in prehispanic times. In this system of agriculture, crops are cultivated on a series of raised beds, which are separated from one another by large and deep water-filled canals. In some regions, rehabilitation of raised fields is now underway. In some cases, it is expanding rapidly because of substantially higher yields. These are due largely to fertile soils, adequate water supply, and protection from frost. As part of a MAB/UNESCO program, we have been studying nutrient and sediment dynamics and retention along transects which include raised fields and canals in the vicinity of Tiwanaku, on the Bolivian side of the Lake Titicaca basin. We have found that high concentrations of nitrate, available phosphorus and turbidity in water decline dramatically as it flows through canals between raised fields. Retention of these nutrients and suspended sediments in canals help maintain soil fertility and reduces pollution of downstream waters and wetlands. Thus there are environmental benefits in the expanding rehabilitation of raised-field agriculture which complements and help sustain the previously demonstrated economic benefits. This appears applicable to a broad range of environments in the Western Hemisphere and other pans of the world.

Environmental Assessment and Restoration Planning for Sensitive Coastal Resources in Isla Vieques, Puerto Rico

Gerard A. Gallagher, III1

1 Geographer, Asst. Regional Manager, Ecology and Environment, Inc., 1203 Governor's Square Blvd. Tallahassee, Florida 32301, USA
Note of the Editor: At the time of the publication of these proceedings, only the abstract of the presentation was available. Further details or the complete paper may be available by contacting the author at the specified address.


Vieques is an island located approximately seven miles east of Puerto Rico in the Caribbean Sea. Of the island's total 33,000 acres, approximately 23,000 acres are owned and used by the United States Navy for conducting training exercises and storing ammunition. The remainder of the island is privately owned. Prior to Navy land acquisition on Vieques in 1943, the island was largely deforested and used for sugar cane and pasture. Over the past 50 years, large areas of Navy-owned lands on Vieques have remained undeveloped and in various stages of reforestation. Remote locations and restricted access of lands under Navy stewardship have afforded an opportunity to preserve significant and highly sensitive natural resources that include extensive mangrove forest, bioluminescent bays, tidal fed and freshwater lagoons, turtle beaches, near shore coral reefs and reef fish associations, sea grass beds, and threatened/endangered species.

In conjunction with a broad-scope environmental assessment of the island, land and watershed management planning activities were conducted that targeted important coastal areas in need of restoration and protection while considering island resident population economic concerns and Navy mission requirements. For approximately 45 drainage basins, detailed analyses were conducted to assess the condition of upland areas, drainages and coastal features. Of particular concern was the accelerated erosion/sedimentation brought on by cattle grazing lease activities, unimproved roads, altered drainages, periodic military training activities, and the resulting adverse impacts imposed upon sensitive coastal resources.

In addition to the above, remnants of several unimproved coastal roads were blocking the ephemeral lagoon openings to the sea, thus eliminating natural tidal flushing of the system. In several locations, mangrove forests were in rapid decline due to increased upland sediment deposition, physical damage by cattle, and hypersalinity brought on by blocked tidal connections.

To assist the Navy's efforts to restore and protect the unique natural resources of Vieques, erosion control and land use management plans were developed and implemented. These plans included improved cattle grazing lease management measures, road improvements, drainage improvements, lagoon tidal access improvements, and establishment of limited-access conservation areas and buffer zones.

Adaptively Assessing and Communicating Complex Resources Issues

Lance H. Gunderson1

1 University of Florida, Department of Zoology, 110 Bartram Hall, Gainesville, Florida 32603, USA
Note of the Editor: At the time of the publication of these proceedings, only the abstract of the presentation was available. Further details or the complete paper may be available by contacting the author at the specified address.


The techniques and practice of adaptive environmental assessment and management (AEAM) as developed by Holling (1978) and Walters (1985) have been applied to resource issues around the world for over two decades. The AEAM approach focuses on uncertainties of resource issues through the identification of key gaps in understanding and knowledge. Computer models provide one means of communication among a diverse set of scientists, engineers, and resource practitioners involved in complex resource issues. Recent advances in computer hardware and software have led to dramatic improvements in visualization techniques. Computer animations of space-time dynamics of key ecosystem functions allows for rapid communication of large amounts of complex information in widely available formats. Computer modelling is limited by scaling issues and the various trade-offs involved with model construction. The AEAM approach has been successfully used to synthesize and integrate information for the Everglades ecosystem, as part of ongoing restoration efforts.

Environmentally Compatible Watershed Management in Venezuela: The Rio Tocuyo Case

Freddy Hermoso and Martin Garcia1

1 National Autonomous Service of Watershed and Soil Conservation, Ministry of Environment and Renewable Natural Resources, Centro Simon Bolivar, Torre Sur - Piso 18, Caracas, Venezuela
Note of the Editor: At the time of the publication of these proceedings, only the abstract of the presentation was available. Further details or the complete paper in Spanish is available by contacting the authors at the specified address.


In Venezuela, most of the major cities are located in northern central coastal corridor. This area contains only 15% of the total water resources in the country and 70% of its population. Clearly, this situation stimulates water use conflicts between the urban and agricultural sectors. Also, there is a progressive decay of water quality and quantity due to unfit management of the land resources near streams and lakes, thus accelerating the erosion and sedimentation processes. In addition, there is an increasing discharge of pesticides, insecticides and other industrial and organic residuals in the water bodies of the region.

In lieu of this situation, it is necessary to take an integrated approach in the management of watersheds in an environmentally compatible national program. The community participation is an integral part of the basin under study. The Venezuelan government, taking into consideration a technical basis for the design of the watershed conservation projects, has taken a sequence of steps to guarantee a sustainable way of promoting a sound basin conservation methodology. A few steps taken include:

the establishment of the National Autonomous Service of Watershed and Land Conservation under the auspices of the Ministry of Environment and Renewable Natural Resources;

the development of a methodological approach for integrated watershed planning;

the implementation of funding mechanisms for adequate watershed management, such as water concession fees, impact fees, and multi-lateral financing.

The Rio Tocuyo case in western Venezuela illustrates the outcome of this integrated effort. It contains a demonstration value based on a scientific basis that would yield appropriate economic development levels while protecting the very same land and water necessary for sustaining life in that watershed.

Lake Chapala and Rio Blanco: Two Case of Environmental Restoration in Western México

Fernando Montes de Oca1

1 Director General, Instituto Autónomo De Investigaciones Ecológicas (INAINE) and Fundación Chapala; Av. Americas 1485, Av. Americas 1485, Guadalajara, Jalisco, México
Note of the Editor: At the time of the publication of these proceedings, only the abstract of the presentation was available. Further details or the complete paper may be available by contacting the author at the specified address.


Lake Chapala, located in western México, is the largest natural reservoir in México, second in altitude in the American continent, and third in size in Latin America. It is also the main source of water supply for a population of 300,000 in Guadalajara. México is divided in 37 hydrological regions, and the Lerma-Chapala-Santiago basin, with 32,500 square kilometers, houses one of every eleven mexicans, and irrigates one eighth of the total agricultural land of the country. Also, this basin contains a third of the industrial infrastructure and 9% of large dams of México.

The most imminent problems of Lake Chapala are water quantity and quality, lack of efficiency in water use, and water hyacinth infestation on 200 of a total surface of 1,200 square kilometers. This study depicts the restoration efforts made at national, state, municipal, and private level in order to restore and perform integrated watershed management in this hydrological unit.

The Rio Blanco Hydrological Basin, located in the municipality of Zapopao, Jalisco, includes 7200 hectares of urban area of Metropolitan Guadalajara and some 8500 hectares of agricultural uses, and the three small dams of La Peñita.

A joint commission of municipal authorities, environmental organizations and citizens groups have developed an integrated management plan for those water bodies and their corresponding basins. Natural and international funds have been sought in order to implement the plans and guarantee the ecological survival of those areas.

The restoration of the Rio Blanco will protect the few natural resources left in the valley of Atemajac and will promote ecotourism in the region.

Environmental Sustainability and the Role of Stewardship

D. W. Moody and E. T. Smith1

1 U.S. Geological Survey, 407 National Center, Reston, Virginia 22092, USA
The concepts of sustainability and stewardship are receiving much attention in the environmental and renewable natural resources literature and in the media. Biodiversity, ecosystem management, watershed management, and sustainability, as applied to renewable natural resources, ecosystems and society in general, are terms that have entered the vocabularies of policymakers, elected officials, and the public. In doing so, these terms have lost some of their precision and meaning (Viederman, 1993) and in the worst cases, they have become buzz words. In fact, different groups - environmentalists, resource managers, economists, and so on - use these words to mean different things, leading to false expectations and misunderstandings between these groups.

Definition of Sustainability

The meaning of sustainability has been and continues to be the subject of much debate. As many as 60 different definitions of sustainability have appeared in the recent literature (Cross, 1992). The traditional notion of sustainability in resource management has generally meant the production of a renewable commodity resource at a rate equal to or greater than its rate of use or harvest. This is the concept of sustained-yield management, as successfully practiced in forestry and agriculture.

In its 1987 report, “Our Common Future,” commonly referred to as the Brundtland Commission report, the United Nations Commission on Environment and Development defined sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs (United Nations, 1987).” Economists, on the other hand, have proposed that sustainable development involves “maximizing the net benefits of economic development, subject to maintaining the services and quality of natural resources over time (Cross, 1992).” The quality of resources, in this context, is the use of renewable resources at a rate that is equal to or less than the rate at which they can be regenerated. Thus, the concept of sustainability can be treated either as an ethical question of what is right or as an economic question. As with most issues, there is a middle ground.

At one time the concept of sustainability was not much more than a poorly defined index of concern about environmental ills. However, this concept may be moving toward more concrete definition. For example, work is now underway on how to expand the national income and product accounts to include measures of nonrenewable resource consumption and related environmental impacts. However, important questions remain:

Is it really necessary to assign monetary values to everything in the accounts? How can this be done?

Why is there only one accounting system, and what imperfections does its use engender?

If we do not carry out such monetization, how can the concept of sustainability be included in national and international planning?

The problem is made more intractable by many uncertainties in the information. We are unsure about the size of potentially recoverable stocks of key resources. It is not certain whether technology for recovering materials will continue to have its historic success. Also, we do not know if technology will continue to find effective and less costly substitutes for scarce materials. We are uncertain about levels of depletion beyond which supposedly renewable resources - forests, fisheries, soils, and perhaps even entire ecosystems - may fail to renew themselves. In an overall sense, we simply do not know to what extent our own and the natural world's capacity for resilience and adaptation can withstand the severe rates of change caused by human actions, especially those actions that employ the technologies of the developed nations.

Each of these uncertainties has a range of possible estimates which leads to impacts that extend from trivial to overwhelming in their implications. Furthermore, if one considers a conceptual model in which many of these estimates are inputs to the system, the combined uncertainties can become so great as to defeat any reasonable estimation process.

Because environmental and natural resource variables are defined as “external diseconomies,” values to represent them are very hard to assign when compared to the well known stocks and flows of economic goods that are now in the national accounts. Our present analytical capabilities limit us to a few methods of analysis. We can use a scenario approach, in which several plausible alternatives are analyzed, each one using different values of environmental variables. The strength of such an approach is the consistency of the picture created by the scenario; it is unlikely that variables will take on values radically inconsistent with the entire picture. Scenarios have the weakness that none of them is a predictor of future conditions; they only represent the results of certain “what if” conditions carried to their logical conclusion.

At present we cannot quantitatively define a permanent state of sustainability. We can, however, make repeated estimates of outcomes based on the playing out alternative scenarios, and attempt to correct our course through time as the future becomes the present.

Ecosystem management approach

Like sustainability, ecosystem management has a variety of meanings. The traditional sustained-yield approach to resource management focused attention on maximizing production constraints imposed by the resource base of soil and water, other uses of the land and water, or environmental issues. Resource managers have given little attention to the other non-commodity products and environmental services provided by the ecosystem.

In contrast, ecosystem management is an ecologically-based approach to the management of natural resources. It makes use of the understanding gained by ecology and related disciplines to make management decisions. It includes the development and implementation of management strategies to maintain the health and productivity of an entire ecosystem or set of ecosystems over long periods of time. By definition, the ecosystem includes humans and their activities. The health of the ecosystem may be measured by its biodiversity, changes in habitat, and productivity. Most importantly, ecosystem management recognizes, and explicitly considers as part of the management strategy, the link between land uses and water resources. The products and services of the ecosystem, upon which the welfare of society depends, are viewed as the outputs of a sustainable ecosystem.

An example of the linkage between human economic welfare and biodiversity is provided by the salmon fisheries of the Pacific Northwest (Nehlsen and others, 1992). The value of these fisheries may be on the order of $1 billion per year in personal income and more than 60,000 jobs. Recent surveys of salmon stocks have revealed 214 stocks at either high risk or moderate risk of extinction or of special concern. Ninety percent of these stocks of salmon are affected by habitat damage from hydropower development, logging, mining, agriculture, and urbanization. Impassable dams, which blocked of upstream spawning grounds and habitat, have led to the extinction of 106 stocks.

The Pacific salmon fisheries cannot be managed on the basis of an individual species. The health of the salmon are too closely tied to the health and condition of entire river basins. Managers and the public must see the fisheries as a component of land and water ecosystems whose health and productivity are tied directly to the productivity of a larger watershed system.

Nehlsen and others (1992), propose that an approach that views ecosystems at a landscape scale and emphasizes conserving the biological diversity of ecosystems, rather than a single species alone, will benefit all animal and plant communities in the system. By looking at the system as a whole, “weak links” and their causes may be found and repaired. To do this the scientific understanding of how large ecosystems function must be improved. Most research has focused on commodity-based resource management systems with little attention given to the sustainability of natural systems whose goods and services lack a market value. An exception is the Ecological Society of America's Sustainable Biosphere Initiative (Lubchenco, 1991), which is aimed at directing ecological research to three major areas: global change, biological diversity, and sustainable ecological systems.

A middle ground between ecologically- and economically-based approaches to resource management has been suggested which is termed eco-development. Managers and planners who apply eco-development (ecologic/economic development) design and organize human activities to allow ecosystems to continue to produce the products and services on which humans depend. In this paradigm, human activities are seen as part of ecological system, and economic and social concerns are considered part of a larger system, rather than as separate and distinct issues.

In August of 1992, the Renewable Natural Resources Foundation (RNRF) sponsored a Congress on Renewable Natural Resource Issues in the 21st Century (Morrisette, 1992). High on the list of issues, for this Congress, was obtaining consensus on the meaning of sustainability and its operational implementation by resource managers, many of whom were trained in the sustainable yield tradition of resource management. Of particular concern to the delegates to the Congress was the need to integrate better the disciplines of ecology and related sciences and economics. Delegates further emphasized the need for better techniques to place value on the non-commodities and environmental services provided by ecosystems so that they can be incorporated into economic analyses. For example, at present we have no way standard method of valuing the environmental uses of water, such as instream flows for habitat or wetland maintenance.

Role of Stewardship

A significant conclusion of the RNRF Congress participants was the need to develop a stewardship ethic to guide the use and development of natural resources. Stewardship implies the caring for or nurturing of something that is entrusted to an individual. This is a philosophical area which goes beyond scientific principles, information, and understanding. If it is accepted that we have a moral responsibility to care for and nurture the land (and water) through practices that maintain or enhance its integrity, value, and beauty for future generations, then this ethic deserves to be widely discussed and debated.

The need for this debate stems from the desirability to involve all the human inhabitants of an ecosystem or watershed in its management. Regulation alone is unlikely to achieve the degree of pollution prevention, water conservation, and environmental protection needed to preserve sustainable ecosystems. To participate in the debates, citizens must be adequately informed about the impacts of their actions on land and water resources. Acquisition of information and understanding is not enough. It must be disseminated to be used. This in turn suggests that interaction between resource scientists, the public, and the media must increase to enhance public understanding of the issues and knowledge of linkages between ecosystem functions and the economy. Non-governmental organizations play an important role in communicating this information to the public and governments as do professional societies.

Professional societies have begun to formulate codes of ethics that are consistent with an ecological approach to resource management. The Society of American Foresters in 1992 adopted the following language as part of their code of ethics (Marshall, 1993):

“A member will advocate and practice land management consistent with ecologically sound principles.”

Other resource-based professional organizations are incorporating similar ideas into their codes of professional ethics.

It seems clear that sustainability must avoid polar opposites; we cannot either “use up” renewable resources as though they were infinite, nor can we leave them undiminished and inviolate. Instead, sustainability may more realistically aim for the preservation and enhancement of the productive potential of the environment. Also, the range of choices available to succeeding generations should not be diminished. This principle might be implemented in many ways:

Investment in new technologies that will reduce waste an improve production.

Changing to new economic activities that will provide employment and be less disruptive to long-term environmental quality.

Improvements in health that will increase productivity and quality of life.

Education that will increase capability to manage and conserve resources as well as better understand the philosophical principles and values of stewardship.

Provision of stable institutions that will enable us to live without imminent risk to health, safety, and welfare.

Many tradeoffs exist. For example, it is difficult to define the extent and rate at which one generation is justified in drawing on an existing set of natural resource endowments in order to meet immediate needs, and simultaneously to invest in the changes needed to sustain or enhance future productive potential.

A crucial balance exists between the need for long-term intergenerational sustainability and a concern for intragenerational equity. The desire for a universal standard of living like that in the developed nations will imply attendant resource consumption and pollutant generation. Yet, it is hard to imagine any succeeding generation that will meet our expectations, if it does not spring from a present generation that sees hope in the future. The model must be one that “bootstraps up” our approach to the world, not one that “spirals down” into global hopelessness and poverty.

The first steps now being taken to grapple with the concept of sustainability are limited and tentative. Much work is needed to define and improve the base of information, to improve analytical capabilities, and to create institutional mechanisms that will permit negotiations, tradeoffs, and compromises. We may be at the start of a process of discovery that will benefit not only ourselves but generations yet to come.

Aldo Leopold captured many of these philosophical issues 45 years ago (Leopold, 1966) in his often cited Sand County Almanac essays that he wrote in 1949:

“That land is a community is the basic concept of ecology, but that land is to be loved and respected is an extension of ethics.... We abuse land because we regard it as a commodity belonging to us. When we see land as a community to which we belong, we may begin to use it with love and respect.”

As we enter the 21st century, perhaps society will adopt Leopold's philosophy.

References Cited

Cross, John F., 1992, Pollution prevention and sustainable development: Renewable resources Journal, v. 10, no. 1, p. 13-17.

Leopold, Aldo, 1966, A sand county almanac: New York, Ballantine Books, 43 p.

Lubchenco, J., 1991, The sustainable biosphere initiative: an ecological research agenda: Ecology, v. 72, p. 371-412.

Marshall, Fred, 1993, Ethical priorities: Journal of Forestry, v. 91, no. 4, p. 12.

Morrisette, P.M., editor, 1992, Congress on Renewable Natural Resources - Critical issues and concepts for the 21st century: Renewable Resources Journal, v. 10, no. 3.

Nehlsen, Willa, Lichatowich, J. A., and Pitstik, R. C., 1992, Pacific salmon and the search for sustainability: Renewable Resources Journal, v. 10, no. 2, p. 20-26.

Society of American Foresters, 1993, Task force report on sustaining long-term forest health and productivity: Bethesda, Maryland, Society of American Foresters, 83 p.

United Nations World Commission on Environment and Development, 1987, Our common future: New York, United Nations.

Viederman, Stephen, 1993, A dream of sustainability: Renewable Resources Journal, v. 11, no. 2, p. 14-15.

Washington State's Marine Waters Environmental Program: A Practical Use of Environmental Assessment Science

Maria Victoria Peeler1

1 Washington State Department of Ecology and the Puget Sound Dredged Disposal Analysis Agencies; 7240 Martin Way, P.O. Box 47703, Olympia, WA 98504-7703, USA
Washington State, located at the Northwest corner of the United States, bordering British Columbia, Canada, is divided by two mountain ranges, the Olympics and the Cascades. Puget Sound, a large body of water created by deep glacial cuts into narrow channels, lies between these two ranges, providing ideal temperate climate, deep harbors, very productive marine waters, and plentiful surface and ground water supplies. Many consider Puget Sound an unusual fjord, where “flushing”, or movement of marine sediments (and therefore contaminants) is small, even though tides can vary as much as ten feet.

Years of industrial and residential development have increased many rivers and streams' natural depositional rate of sediments into the shallower urban bays, carrying increased contamination to the bays, and routinely clogging commercial shipping lanes. Destruction of natural wetlands and marshes reduced nature's ability to reduce stormwater discharges. Washington is dependent on shipping, marine commerce, and naval facilities to maintain a healthy economy. This requires that routine, maintenance dredging be conducted along Puget Sound, Greys Harbor and the Columbia River by the U.S. Army Corps of Engineers.

However, increased concern for Washington's shoreline by local and state government agencies, citizens and scientists, reduced the dredging and disposal activities in the early 1980s. In 1982 the State legislature created the Puget Sound Water Quality Authority, giving them the mandate of developing an environmental protection plan for Puget Sound. The Plan includes sediment management elements, requiring source control and education as primary tools to implement water and sediment quality improvements in the Sound.

Two state natural resources agencies have primary responsibility for marine sediment management in Washington State: the Department of Natural Resources (DNR), which manages state lands and issues leases to entities who propose development for water dependent uses; and the Department of Ecology (Ecology), which is responsible for regulatory oversight of Washington's environment.

After several attempts at managing these resources independently, coordinating poorly with the federal agencies, and receiving continued data from environmental samples revealing that contamination in some areas of Puget Sound, such as Eagle Harbor and Commencement Bay, had reached critical levels, Ecology and DNR decided to join expertise and resources. In 1984 the State of Washington entered into an agreement with the Federal EPA Region X (Seattle) office and the Corps of Engineers Seattle District to provide consistent scientific review and management of sediment quality in Puget Sound, naming it the Puget Sound Dredged and Disposal Analysis (PSDDA) program.

The PSDDA program is unique because it operates completely in a cooperative, non-regulatory atmosphere. It is also unique in several other ways: 1) although three of the four agencies have independent regulatory authority under the Federal Clean Water Act to manage water and sediment quality, and the fourth has final say on the use of the state aquatic lands, all four agencies share responsibility for expenses, studies, review of projects, management of the program and communication with the public; 2) consensus is always reached before an action is taken; 3) all decisions are based on a carefully laid out plan that includes years of scientific research and development, pre-approved disposal areas, and commitment to conduct long-term monitoring of all actions and take corrective action, if necessary; 4) all proposed changes to the program are subject to public review, allowing the public to propose revisions, and committing to the public to review and, if possible, implement their requests; and, finally, 5) the program operates under the philosophy that to maintain good water quality, management of sediments is critical.

Quality of the sediment is assessed by testing the material for 57 “chemicals of concern” (with an option to add more if historic practices warrant it). “Trigger” levels of contamination were established in 1984 by conducting extensive chemical analysis of local sediments, then conducting bioassay studies on five selected native marine organisms to determine what level of contamination in the sediments triggered a negative response on all five species. Statistical calculations were used to determine which levels of contamination most consistently triggered negative effects on all suites of bioassays, and on individual species. Reliability and predictability of effects were measured to determine if responses were statistically valid. This technique is commonly referred to as the Apparent Effects Thresholds (AETs).

The AETs allowed the PSDDA agencies to establish numerical regulatory levels to determine whether sediments passed or failed suitability for disposal. An exceedance of “maximum levels” (MLs) of contamination immediately determine the sediments are not suitable for disposal in open water. The full environmental assessment process also allows further testing of sediments if exceedance of “screening levels” (SLs) occurs.

This tiered testing approach allows results from bioassays, bioaccumulation and benthic studies to be used to make the determination whether the sediments are suitable for dredging and disposal in Puget Sound. Sediments that fail the tests can still be dredged, but must be placed in confined disposal sites, mostly upland (although near-shore sites can be proposed if appropriately managed). This approach allows the applicant to decide whether they wish to spend minimum funds and efforts by exclusively testing for chemistry (the most inexpensive of options), and abiding by its established trigger levels; or, following through with biological testing to determine whether the sediments will or will not affect marine populations.

The PSDDA program manages, on average, 8 million cubic yards of sediments per year, and tests over 10 million. Testing is conducted by taking surficial samples (generally collected with a Van Veen grab sampler) and core samples (generally using a Vibracore), allowing compositing of several adjacent samples to obtain “dredged material management units” (DMMUs) - or prisms that can be dredged in one cut. Enough sediments are always collected to also run bioassay tests and bioaccumulation tests, if tier 2 testing becomes necessary.

PSDDA program policy does not allow dredging projects to leave exposed materials which test more contaminated than prior to dredging, thus ensuring that the dredging site will, at a minimum, have the same water and sediment quality conditions found prior to dredging.

Every year extensive physical and chemical monitoring is conducted by the Corps and DNR, respectively, and the data entered by Ecology into a multi-task relational database called SEDQUAL. Comparison of historical data and new data is conducted to determine trends. Monitoring results at the end of each dredging year cycle have shown continued improvement in the quality of the sediments and waters in the disposal areas.

In 1991 Washington State adopted the majority of PSDDA's procedures in regulatory form as the Sediment Management Standards (SMS), under the State's water quality and waste clean-up regulations. EPA Region X approved the SMS as water quality standards in accordance with the Federal Clean Water Act, and as part of Washington's Comprehensive Conservation and Management Plan (CCMP) - the first in the Nation.

The two programs are consistent with each other primarily because both use an established sediment sampling protocol originally developed for the Puget Sound area, but now used in all of Washington's marine sediments. We refer to these as the Puget Sound Estuary Program (PSEP) protocols.

The SMS provide an additional dimension to the management of sediments in Washington marine waters. A portion of the regulation requires “remediation” of sediments at a certain level of contamination. This trigger level is referred to as “minimum clean-up level” (MCULs), and essentially match with PSDDA's MLs (see attached relational graph). Because the SMS are primarily concerned with the quality of the sediments in the “biological active zone”, or the first 10 centimeters, compositing of these samples is not allowed, making sampling a bit more complicated. This practice is not necessary if preliminary review of historical records indicate the area is pristine or not heavily affected by human activities.

Three portions of the SMS are not complete: 1) determination of how human health effects will be factored into the current chemical standards; 2) development and implementation of fresh water sediment standards; and, 3) interpretive regulatory guidelines for assessment of benthic community populations. PSDDA will use and incorporate both the information obtained for development of human health criteria, and assessment of benthic populations.

The PSDDA program is working on refinements to the suite of bioassays, and bioassay protocol updates. Studies have been completed on the 20-day Neanthes arenaceodentata chronic-sublethal bioassay, and the larval toxicity bioassays. Under study is the Microtox toxicity bioassay (including the new solid phase test), and the possibility that sensitivity of the amphipod bioassay may be jeopardized if species substitution is used. The SMS science advisory board will review this information to determine if revision of the standards is warranted.

These scientific improvements are incorporated into PSDDA by conducting continuing research, proposing the improvement to the public in an annual report and public notice, and obtaining public comment and proposals in an annual review meeting held every spring. The SMS will incorporate improvements during triennial modifications. As an example, last year PSDDA incorporated the 20-day chronic/sublethal Neanthes arenaceodentata bioassay test as part of the suite of bioassays. Washington State is the first in the nation to use this regulatory interpretation tool. The Neanthes bioassay was studied for more than six years before the PSDDA program decided the test increased the overall accuracy of the suite of bioassays.

Can shortcuts be taken and costs of testing be reduced further without jeopardizing the hard-won improvement of water and sediment quality in Puget Sound?

The PSDDA program believes that as the program matures and experience is gained, regulatory tools will become cheaper and easier to use. Right now, Ecology is using the SEDQUAL database, with a data bank that has increased one-hundred-fold, to recalculate the AETs. Preliminary results indicate the new trigger levels in some chemicals will more accurately predict sublethal and lethal effects to biota.

Can the rest of the U.S. and Americas benefit from our states' knowledge and experience?

The PSDDA agencies have presented the program to Oregon, Alaska, San Francisco, and British Columbia governments. Oregon and San Francisco are proceeding to implement this model. Alaska and British Columbia already use large portions of the PSEP and PSDDA protocols and regulatory interpretations. A presentation in France last year precipitated queries from the Netherlands and a visit from New Zealand scientists. New Zealand is in the process of adopting a scaled down version of the PSDDA program.

The knowledge we have gained can be used easily by any government in need of managing their water and sediment quality, by adapting Washington's process to their own needs. We consider it an honor to provide our information to others, and look forward to a closer partnership with other governments that can provide us their experiences and studies, thus enhancing our knowledge as well.


Environmental Effects of Contaminated Sediments

Sediments with elevated concentrations of chemical contaminants
Adverse effects to laboratory test animals
Fewer animals living on and in contaminated sediments
Bottomfish fin rot, gill lesions, reproductive failure and liver tumors
Local health department fishery advisories warning against human consumption

Discharge and Sediment Liabilities
Unresolved legal issue: whether a regulatory discharge permit that restricts, yet allows sediment contamination on someone else's land constitutes an action subject to proprietary laws

Landowner approval over regulatory permits could result in the landowner holding the discharger hostage. And there are legal questions about Ecology delegating regulatory powers to the landowner

Indemnifying the landowner for contamination that Ecology permits to be placed on their land would illegally rewrite legislated liability standards

Rule states that regulatory action does not address any proprietary requirements

Rule aligns the sediment standards so discharges do not create new cleanup sites

Rule establishes accountability to the discharger for sediment effects

State agencies are integrating regulatory and proprietary interests

Sediment Cleanup Standards

Example of the “application model” - the rule defines sediment cleanup standards using a “range of effects”

Cleanup standard is defined on a site-specific basis, as close as practicable to the sediment quality standards (the “cleanup objective”), not to exceed the “minimum cleanup level”

In defining practicability, net environmental effects, natural recovery rates, engineering feasibility and cost are all factors that are considered when determining the site cleanup standards

Sediment Dilution Zones

The rule uses “sediment dilution zones” as the vehicle for authorizing adverse effects over the “no effects” sediment quality standards

There are two types of dilution zones described in the rule: “sediment impact zones” and “sediment recovery zones”

For ongoing discharges, the rule allows the State to authorize an area outside the discharge known as a “sediment impact zone” within which the discharge can exceed the lower standard, but not the higher, “minor effects” standard

For historic contamination subject to cleanup, the State can determine that portion of the contamination above the “no effects” standard and below the “minor effects” standard does not need to be cleaned up - thus leaving a “sediment recovery zone”

The same computer models are used to predict sediment impact zones from discharge effluent data and to predict the rate of natural recovery in sediment recovery zones

Regulatory Application Model

Sediment quality standards represent a “no effects” goal

Exceeding the sediment quality standard does not mean terminate discharge or start cleanup

“No effects” standard was established solely using scientific information - not engineering feasibility or cost factors that are part of regulatory decisions

A second sediment standard, the “minor adverse effects level”, acts as an upper bound or ceiling on regulatory decisions

Between the two standards, source control and cleanup decisions are made in consideration of net environmental effects and cost/feasibility tradeoffs

This “allowable range of effects” necessarily requires technical and policy judgement during implementation

Dredged Material Disposal Standards

Per Element S-4 of the Puget Sound Plan, Ecology is developing a second sediment rule addressing dredging and disposal of sediments derived from navigation and cleanup projects

Dredged Material Management Standards, Chapter 173-227 WAC, will specify technical and procedural requirements for all dredging and dredged material disposal actions

Rule will codify key features of the current Puget Sound Dredged Disposal Analysis program

Rule will provide “minimum functional standards” for disposal of sediments in upland disposal sites (pursuant to Chapter 173-304 WAC)

Rule will be linked to the Dangerous Waste rule (Chapter 173-304 WAC) to address hazardous sediments

Draft guidance manual due April 1992; draft rule scheduled for release by end of 1992

Sediment Management Standards

Ecology recently adopted a new rule known as the Sediment Management Standards, Chapter 173-204 of the Washington Administrative Code

Rule establishes a set of narrative, chemical and biological criteria as 'sediment quality standards'

Rule describes use of standards in existing source control programs designed to control the discharge of contaminants (e.g., wastewater discharge permits)

Rule applies the sediment quality standards in the sediment cleanup decision process

Rule was recently approved by EPA as part of the State's “water quality standards” pursuant to Section 303 of the Clean Water Act

Institutional Challenges of Sediment Management

Like water, sediments are an environmental medium and are subject to aquatic protection laws

Unlike water, if sediments are picked up, they are similar to any other solid waste material

Contaminated sediments result in cleanup liabilities to the discharger, the waterfront developer and the landowner

Sediment management requires an innovative blend of legal mandates and procedures to effectively integrate water quality, dredging and cleanup programs

Cross-Program Implications

A key objective of the sediment rule was to ensure that the various government programs that affect sediment quality worked in harmony with one another

Same standards of quality are established for all regulatory programs

We do not want permitted discharge zones that will then result in increased disposal costs and liabilities to navigation dredgers

For cleanup programs, the upper standard is a cleanup trigger (“cleanup screening level”) above which we will list a site for active cleanup, below which we will not list a site for active cleanup

The status of point and nonpoint source controls is a key consideration in determining appropriate cleanup actions in sediments

This arrangement ensures that we will not be permitting discharges or creating dredged material disposal sites that will later become future cleanup sites.


Aquatic Weed Control in the Yarinacocha Pucallpa Lagoon

Olga Rios Del Aguila1

1 Regional Agricultural Director, Ministry of Agriculture, Jr. José Gálvez No. 287, Pucallpa, Ucayali, Perú
Note of the Editor: At the time of the publication of these proceedings, only the abstract of the presentation was available. Further details or the complete paper may be available by contacting the author at the specified address.


The Yarinacocha lagoon is located in the Ucayali region of Peru. The average annual temperature in the region is around 80°F (26.29°C) with an average precipitation of 70 inches/year (1777 m.m. year).

Since 1982 an increase ofwater hyacinth, water lettuce, and umbrella flatsedge has been observed. Approximately 15% of the surface area of the lagoon (180 Ha.) is covered with aquatic plants. In other lagoons and lakes almost 100% of the surface area is covered, making these water bodies unnavigable. In addition some of the plant roots are fixed in the soils creating secondary forests when the area dried out.

This invasion of aquatic plants is due to the disappearance of the manatees, tapirs, and fishes that were caused by boat traffic, human consumption and deforestation.

The principal methods of weed control are mechanical removal, herbicides that do not cause contamination and biological methods through the use of crickets and herbivorous fish.

There are also preventative methods such as promoting the reproduction of manatees, fresh water turtles, placing control on fishing and finding additional use for aquatic weeds such as food products and fertilizer.

Sub-track: Protection and Restoration Strategies

The Role of Non-Governmental Organizations in Environmental Assessment in the Pantanal Region
Conserving Aquatic Ecosystems for Sustainable Development
Management of Aquatic Ecosystems - The Pantanal Case
The Everglades Nutrient Removal Project: Hydrology, Hydrodynamics and Operation
Lessons Learned from Five Decades of Wetland Restoration and Creation in North America
The Role of Wetland Filters in Ecosystem Restoration
Development of the Kissimmee River Restoration Plan: Lessons Learned and Recommendations for Comprehensive Restoration Projects

The Role of Non-Governmental Organizations in Environmental Assessment in the Pantanal Region

Joaquim Rondon Rocha Azevedo1

1 Executive Director of Sociedade de Defesa do Pantanal - SODEPAN, Av. Americo Carlos Da Costa 320, 79080-170 Campo Grande, MS, Brazil
By now everyone is more or less acquainted with the context of the Pantanal, a vast wetland system located in South America. It is a very complex region, with a very high level of interconnectedness among the subregions that form it as well as the neighboring regions. We could mention, as an example, how it's hydrology influences the whole La Plata region, both by slowing down the flow of water coming from the upper basin into the Paraguay river, and by filtering solids in suspension and thus turning that water clearer. The cultural integration among the different regions of La Plata river basin is another factor that adds to that complexity.

We believe that, in that context, environmental assessment, like any other environmental issue, needs an “ecosystem-level approach” in order to be effective. This “ecosystem-level approach” should lead to an integration, from the beginning, of the multiple aspects involved, such as biologic, physiographic, socio-economic, and policy! providing broad and coherent analysis and solutions.

We have found that this kind of approach for environmental assessment stresses two points: building capacity for analysis, and communications. In the course of SODEPAN's programs, we've identified some actions to be taken, as well as constraints, regarding these two points, which I would like to talk about. First, however, it is necessary to introduce you to SODEPAN.

SODEPAN stands for Sociedade de Defesa do Pantanal. It is a private, non-profit organization founded by land owners of the Pantanal concerned with the maintenance of the ecological balance of the region. In its eight years of existence, SODEPAN has worked jointly with other agencies in the research of behavioral and biological needs of “flagship” species of the Pantanal, the ecology of flooded areas, and migration of fish, just to name a few examples. It has also conducted a diagnostic survey of the local political base and attitudes toward conservation in each microwatershed of the Upper Paraguay river basin, and has initiated a coalition of environmental groups in the La Plata region to address development issues such as MERCOSUR and the Hidrovia.

A recent reorganization and strategic planning session prepared SODEPAN to integrate the broad effort for the conservation of the Pantanal, which involves many different actors. The two issues of environmental assessment I intend to address, communications and capacity building, should be focused by the organization's programs from the perspective of our positioning within this effort.


As for capacity building, we envision three major courses of action:

1. Develop capacity to assess major development schemes

Direct and indirect impact assessment is reasonably well developed already. We have participated in workshops to improve capability of analyzing environmental impact assessments (EIAs) with satisfactory results. However, sometimes this is not enough. Much of the assessment is based on incomplete studies, that reveal gaps in knowledge that must be fulfilled.

In addition, development projects are often related to other projects, which leads to the necessity for a broader understanding of the implications of each project in a wider development scheme, in order to make a comprehensive analysis. Using the example of the Hidrovia Project, it is predictable that it will influence other projects such as monocrop agriculture development in the west of Brazil, or the ZPE (zone for processing and exporting of industrialized goods) in Corumba.

2. Investigation of alternative scenarios

The need for the investigation of alternative scenarios can be explained in the context of the polarization between development and conservation that some development agencies suggest. We often run short of arguments to counter that position, because there are no studies that indicate the alternatives that can potentially integrate development and conservation. Elaborating models, assessing available technology that could be useful, and most important, valuing the natural resources and the potential economical losses due to bad use is essential.

3. Develop instruments for micro-scale planning

In a region where 95% of the land is privately owned, any conservation strategy needy support on that level. Environmental assessment must not only take this into account to be socially sound, but also be operational in orienting and promoting actions on that level. Rapid Environmental Assessment techniques can be a solution, in the sense that it is accessible. Also, in microwatershed actions and planning, like in Bonito or Rio Verde, it would be useful.


The complexity of the Pantanal region, and the number of actors involved in the process of its development create a demand for coordination among these actors, and most important, a necessity for consensus around the guidelines for the development of the region. This situation presents an opportunity for a number of actions, some of which SODEPAN is currently undertaking.

1. Educate involved community groups

It is necessary to inform the involved community groups about development projects and policy making, in terms of their potential benefits and threats. In order to do that, we've developed a program with the following activities: Circulate information through media, create a telephone information system (hot-line), and increasing the circulation of the organization's newsletter.

2. Build sound terms of reference for development programs and policy-making

Once the communities are well informed, it is necessary to create mechanisms that ensure their participation in the decision-making process. SODEPAN is currently carrying out a program of public hearings that will provide the baseline for the Mato Grosso do Sul state environmental policy act. This program will be enhanced and incorporate the use of focus groups.

3. Develop methodologies/coordinate efforts

The coordination of efforts of the various groups involved in the process of development of the Pantanal is essential. Not one single group can undertake this task alone. SODEPAN envisions creating a computer network and hold meetings with environmental and development agencies of the whole La Plata region, thus supporting open debate regarding issues of common interest and the development of appropriate and comprehensive methodologies to address these issues. This network could also serve as an early warning system of activities that could potentially create impacts on the environment.


Even though many of the programs mentioned are already being carried out, SODEPAN still faces some major problems in getting them accomplished. It is a temptation to say that the major constraint to implement these actions is the lack of financial and technical resources. This is a reality in most of Latin American organizations, specially NGOs. However, I think that the challenge we face, the development of innovative methods to cope with complex scenarios such as the Pantanal, needs a bilateral, collaborative approach, in which local institutions would receive the resources, but would actively help adapting them to their specific reality. In return, methods developed from the integration of conceptual frameworks and real parameters, would certainly be useful once transposed to other complex scenarios. SODEPAN We certainly need help to overcome these constraints, but looking at them from the perspective of the opportunities they present, one sees that the whole matter is relevant not only on local level, but can also bring benefits to the whole world.

Conserving Aquatic Ecosystems for Sustainable Development

Gonzalo Castro, Ph.D.1

1 Executive Director, Wetlands for the Americas, P.O. Box 1770, Manomet, MA 02345, USA
Aquatic ecosystems, or wetlands, are an integral component of the water cycle and are thus inextricably linked with the management of water resources. Given the variety and importance of the services that wetlands provide to society, their conservation must be a central component of any rational strategy for the long-term utilization of water. In this paper, I review the connections between aquatic ecosystems (i.e. wetlands) and sustainable development, and stress the need for society to incorporate wetland conservation within the formulation of water use policies.


Wetlands, or aquatic ecosystems, are defined by the Convention on Wetlands of International Importance (Ramsar Convention) as “Areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static, flowing, fresh, brackish or salt, including areas of marine water, the depth of which at low tide does not exceed six meters.” As a descriptive definition, it is broad and encompasses a variety of aquatic ecosystems, including reef and seagrass beds, mudflats, mangroves, estuaries, rivers, marshes, swamp forests, and lakes. Because this is a definition in an international convention, it is often adopted as the “official” definition of a wetland (Davies and Claridge 1993).

There are numerous ways to classify wetlands, and a variety of criteria can be applied to this end. Again, the Ramsar classification is widely recommended (Dugan 1992), and includes Salt Water Wetlands (Marine, Estuarine, Lagoonal, and Saline with internal drainage); Freshwater Wetlands (Riverine, Lacustrine, and Palustrine); and Man-Made Wetlands (Aquaculture/Mariculture, Agriculture, Salt Exploitation, Urban/Industrial, and Storage).


Traditionally, wetlands have been considered useless ecosystems. Widespread ignorance about the important benefits that wetlands provide to human societies has contributed to this notion, promoting the destruction and degradation of wetlands throughout the world.

The conterminous U.S. has lost an estimated 53-55 percent of its original wetlands. By the 1980's, twenty-two states had lost 50 percent or more of the wetland areas that were contained within state borders (Dahl 1990). This loss is equivalent to an area larger than the state of California, and translates into a loss of one acre every single minute for the last two hundred years. Many human activities are responsible for the draining, filling, flooding, and degradation of wetlands and riparian habitats. Agriculture, dams and flood control projects, road building, urban development, pollution discharges, groundwater pumping, and deforestation are important agents of wetland destruction. Most wetland degradation occurs from changes to the land base, primarily due to agriculture (Dahl, pers. comm.).

Although reliable figures are not available for other countries in the hemisphere, evidence indicates that wetlands are rapidly being destroyed and degraded everywhere. Many countries that have been studied have shown losses in mangrove cover of more than 50%. Throughout Mexico and the Caribbean, many coastal wetlands have been lost because of tourism expansion. Agricultural runoff and other sources of contamination are also a serious threat in South America, especially in the La Plata Basin. Mining waste is dumped directly into many high Andean lakes, especially in Peru and Bolivia. Conversion to rice fields is also a serious problem, especially in Uruguay and Brazil. These losses erode many important wetland benefits and impinge upon their ability to act as the basis for future sustainable development.


Wetlands provide a great variety of benefits to society. These benefits are often referred to as functions, uses, values and attributes, features, and goods or services, and are defined as any of these terms which may have a value to people, wildlife, natural systems or natural processes (Claridge 1991). According to Adamus and Stockwell (1983), there are about 75 such characteristics of wetlands that can be considered beneficial. In this paper, I classify wetland benefits as functions, products, and attributes following Davies and Claridge (1993) and Dugan (1992).

Wetland Functions

Popocatépetl volcano

Popocatepetl is one of Mexico's most active volcanoes. After almost 50 years of dormancy, "Popo" came back to life in 1994 and has since then been producing powerful explosions at irregular intervals.
In the past centuries befor European invasions, large eruptions produced giant mud flows that have buried Atzteque settlements, even entire pyramids.


Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, towers to 5426 m 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 250-450 m deep crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano.
At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas south of the volcano. The modern volcano was constructed to the south of the late-Pleistocene to Holocene El Fraile cone. Three major plinian eruptions, the most recent of which took place about 800 AD, have occurred from Popocatépetl since the mid Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since precolumbian time.
Source: GVP, Smithsonian Institution - Popocatepetl information

Popocatépetl Photos:

Popocatepetl is one of Mexico's most active volcanoes and also part of an Aztec legend, a warrior who fell in love with a young woman (Iztaccihuatl) who died while he was...
Volcano Tecajete, Popocatepetl in clouds (background), view from San Pedro Cholula , Mexico (Photo: WNomad)

Latest satellite images

Popocatepetl and Iztaccíhuatl
Photo from the International Space Station showing a pair of volcanoes in Mexico: active Popocatepetl (left) and extinct Iztaccíhuatl.(right).
This 2003 photo from the International Space Station shows a pair of volcanoes in Mexico. As part of the “Ring of Fire” stretching around the Pacific, Mexico hosts several of the world’s most continually active volcanoes, including the massive Popocatepetl (Aztec for "smoking mountain") at left. The neighboring volcano is Iztaccíhuatl (the "Woman in White"). The faint plume emanating from Popocatepetl’s summit crater shows the ever-present hazard the volcano represents to the 25 million people living in the region, including the nearby city of Amecameca, as well as the metropolitan centers of Mexico City to the northwest and Puebla to the east.
Credit: NASA

Last update: 7 Mar 2018
Typical eruption style: Dominantly explosive, construction of lava domes. Plinian eruptions at intervals of several centuries or few thousands of years, vulcanian and strombolian activity in intermittent phases.
Popocatépetl volcano eruptions: 1345-47, 1354, 1363(?), 1488, 1504, 1509(?), 1512, 1518, 1519-23(?), 1528, 1530, 1539-40, 1542, 1548, 1571, 1580, 1590, 1592-94, 1642, 1663-65, 1666-67, 1697, 1720, 1802-04, 1827(?), 1834(?), 1852(?), 1919-22, 1923-24, 1925-27(?), 1933, 1942-43, 1947, 1994-95, 1996-2003, 2004-ongoingNo recent earthquakes
TimeMag. / DepthDistanceLocation

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