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Freshwater Management Series No. 5

Guidelines for the Integrated Management of the Watershed
- Phytotechnology and Ecohydrology -

F. Policy and institutional approaches: the ecohydrology challenge

The maintenance of homeostatic equilibrium in the ecosystem in order to ensure its ability to continue to produce the desired resources, and to preserve and even enhance its resilience and carrying capacity to assimilate natural and anthropogenic stresses, is a key element in achieving sustainable development. The ecohydrological approach, by integrating knowledge of biota with that on the whole range of hydrological processes at medium or mesoscale (which includes microhabitats, river systems, and catchment areas), provides the scientific background for maintaining the integrity of ecological processes. This integration is one of the three key considerations on which the concept of sustainable development has been built, as depicted in Figure 1.15.

Being that water is essential to human life and economic growth, sound management of water resources is central to sustainable development. Ecohydrology, therefore, recognises that sustainable development is dependent on the ability of the ecosystem to maintain the evolutionary-established processes and patterns of water and nutrient circulation, and energy flows, at the basin scale.

In promoting the integration of the catchment and biota into a Platonian superorganism, the use of ecosystem properties becomes a management tool, within which ecohydrology can address fundamental aspects of water resources management. In effect, it provides the sound scientific basis for adopting the watershed as the basic planning unit. By incorporating the concept of improved ecosystem resilience into the management tool, ecohydrology strengthens the rationale for adopting a preventive, holistic, and global approach to the watershed - as opposed to the reactive, sectoral, and site specific approach typical of present extended practices in water resources management. At the same time, ecohydrology stresses the importance of ecotechnological measures as an integral component of water management, complementing standard engineering approaches.

But water resources management goes beyond these fundamental aspects, concerning the understanding of natural processes and adoption of technological approaches, to address the optimum development and use of water resources and their protection. Further, development, use, and protection, in terms of an ecohydrological approach, extend to present and intergenerational equity concerns, and a full accounting for the economic, social, and environmental values of water. Thus, ecohydrology involves policy, institutional, economic, social, environmental and legal issues which configure a multidimensional space which needs to be integrated by means of sound management tools and approaches.

Fig. 1.15. Interrelationships among economic growth, equity and sustainability

During recent decades, knowledge derived from successes and failures in the management of the environment and natural resources, particularly water, has contributed to build up a well documented set of basic principles for sound management of water and other natural resources, and for the protection of the environment, particularly aquatic ecosystems. These principles constitute a rationale, founded upon scientific knowledge, which, according to generalised worldwide experience, guaranteeing a better approach to the global objective of "sustainable management of water resources, including the protection of aquatic ecosystems and freshwater living resources".

Mar del Plata 1977, Dublin 1992, RúŚ de Janeiro 1992, and many other, renowned international meetings are milestones at which some basic global understandings, such as the rational use of water; integrated management of water resources; use of the watershed as a basic planning unit; the social and economic value of water; the role of water in ecosystem protection; etc., have been achieved. Together with the need for sound management tools, such as proper regulatory frameworks, the incorporation and transfer of "clean" technologies, environmental education, public participation, access to information, use of economic and financial instruments, and the promotion of sustainable practices, etc., these principles have gained international consensus. In particular, Dublin’s principles1 stand out among them because of their extended and complete recognition.

The international community, in its search for universal truths and simplicity, attempted to summarise this global knowledge in so-called "paradigms" which express, in a few words, a complex set of scientific, technological, policy, institutional, social, economic, and environmental issues. At the United Nations Conference on Environment and Development (UNCED 92), "sustainable development" - based on the definition proposed by the renowned Bruntland Commission2 - was incorporated into a broadly-accepted paradigm expressing the need to carry out development actions within the framework of economic efficiency, social acceptability, and ecological integrity.

With regard to water resources, Chapter 18 of UNCED´s Agenda 21 noted the concept of integrated water resources management, based on "the perception of water as an integral part of the ecosystem, a natural resource and a social and economic good, whose quantity and quality determine the nature of its utilization". Including the Dublin principles, integrated water resources management is presently being widely adopted as the paradigm which should drive society toward sustainable development of water resources. The Global Water Partnership (GWP), which is intensively contributing to spread the concept, adopted the following definition: "Integrated water resources management is a process that promotes the coordinated development and management of water, land and related resources in order to maximize the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems."

The term "integrated" implies a multidimensional concept which calls for the simultaneous consideration of natural resources, social, cultural, institutional, regulatory, economic, and political issues in the watershed. As a reaction to the sectoral, thematic, and geographical fragmentation that has characterised present water resources management in most parts of the world, integrated water resources management pursues integration within and between the natural and socioeconomic components of the environment, utilising the river basin as the natural planning unit.

The concept of Integrated Water Resources Management - in contrast to "traditional," fragmented water resources management - at its most fundamental level is as concerned with the management of water demand as with its supply. Thus, integration can be considered within two basic systems:

  • the natural system, with its critical importance for resource availability and quality, and
  • the human system, which fundamentally determines the levels of resource use, waste production, and pollution of the resource, and which must also set development priorities.

Integration has to occur both within and between these categories, taking into account variability in time and space3.

Ecohydrology is another "paradigm" which addresses the integrated study and use of ecosystems, including their hydrological characteristics and processes, and their combined potential to influence water dynamics and quality, particularly at the catchment scale. In terms of integrated water resources management, it addresses, and scientifically strongly supports, integration within the natural system as well as providing guiding principles and tools to integrate a consideration of ecosystem components within the development framework. Furthermore it enhances a preventive approach, through ecosystem resilience improvement, that amplifies opportunities for achieving sustainable development.

Within the context of integrated water resources management, ecohydrology should be incorporated into the objectives and policy framework for water management at the highest institutional levels, as well as be disseminated at the community level to promote environmental awareness, enhance water resources values, and stimulate their protection.

Ecohydrology also provides scientific support for the use of the watershed as the planning unit of choice for water resources management. In this manner, ecohydrology contributes to building a basin approach to water resources management at the community level. In effect, ecohydrology creates a common watershed vision that is fundamental for promoting the active involvement and participation of stakeholders, and for putting into effect a process of "social negotiation" which should be at the root of all decision-making within a basin. Also, it facilitates the solution of downstream-upstream conflicts through enhancing so-called "hydro-solidarity."

Ecohydrology also helps to strengthen the incorporation of social and environmental values into strategic water resources planning at the watershed level, facilitating technological approaches that will contribute to sustainability, making use of ecosystem properties. Improved ecosystem resilience and ecotechnologies may well be an integral part of pollution prevention and water quality restoration programs and measures.

By simultaneously addressing both hydrological and biotic processes at various levels (microhabitat, river systems, entire watershed) within the ecosystem, ecohydrology provides a sound basis for land and water use, as well as for integrated surface and ground water management. Thus, ecohydrological principles may strongly influence the conceptual basis upon which regulatory and economic instruments are devised to induce human behaviours compatible with the objectives and goals of strategic, basin-scale planning.

Because of its holistic and basin wide approach, ecohydrology requires a strong commitment from governments and water users to strengthen the knowledge base - in terms of monitoring and data management, research and technological development. It also involves the joint efforts of governmental agencies and stakeholders across various jurisdictional boundaries within a basin to coordinate data gathering, information exchange, and joint interpretation of ecosystem functioning, root cause analyses, and the effects of human interventions on ecosystem components. It basically requires that stakeholders, users, and civil society become aware of its principles and guidelines for action, thus promoting a bottom up process that will instill ecohydrological principles into institutional and legal frameworks.

Therefore, ecohydrology should evolve from a scientific approach to an institutional approach, within the framework of integrated water resources management, incorporating the economic, financial and social dimensions that currently characterise globally-accepted paradigms.

1 (i) Freshwater is a finite and vulnerable resource, essential to sustain life, development and the environment; 
(ii) Water has an economic value in all its competing uses and should be recognized as an economic good; 
(iii) Decisions are to be taken at the lowest appropriate level, with public consultation and involvement of users in the planning and implementation of water projects; 
(iv) Women play a central role in the provision, management and safeguarding of water. International Conference on Water and the Environment Development Issues for the 21st Century. Dublin, January 1992.

2 Sustainable development is the satisfaction of present needs without compromising the ability of future generations to satisfy theirs.

3 Integrated Water Resources Management, TAC Background Papers No. 4. Global water Partnership. Technical Advisory Committee, 2000.


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