Dniester River Basin subject of international meeting
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"Integrated Management of Natural Resources in the
Transboundary Dniester River Basin"
16-17 September 2004
Chisinau, Republic of Moldova
TRANSBOUNDARY RIVER BASIN MANAGEMENT
Convention on Wetlands, Ramsar Secretariat, 28 rue Mauverney, CH-1196 Gland, Switzerland
Tel.: (+41) 22 999 01 73, Fax (+41) 22 999 01 69, E-mail: email@example.com, www.ramsar.org
River basins or river catchments (the land area between the source and the mouth of a river including all of the lands that drain into the river) and coastal and marine systems influenced by catchment discharges, are important geographical units for considering the management of water resources and wetlands. Where river basins are transboundary, this requires regular and structured consultation, coordination and cooperation among all states sharing the catchment. Rapid and unsustainable development of river basins and their wetlands has led to the disruption of natural hydrological cycles. In many cases this has resulted in greater frequency and severity of flooding, drought and pollution. Appropriate transnational planning, protection and allocation of water to wetlands is essential to avoid disaster and enable these ecosystems to continue to provide important goods and services to local communities.
Assessing and enhancing the role of wetlands in water management
Wetlands perform a host of ecological and hydrological functions. These include mitigating the impacts of floods, reducing erosion, recharging groundwater and maintaining or improving water quality. Wetlands can be managed to secure a range of objectives in water resources management, such as to maintain water supply and quality, to recharge groundwaters, to reduce erosion, and to protect the human population from floods.
While it may be desirable to have long-term and detailed studies, it is often more appropriate to use rapid assessment techniques to determine the relative importance and functions of wetlands within a river basin. Once the functions have been determined, it is possible to assess the role that the wetlands could play in the management of water resources within a river basin. Numerous studies throughout the world have shown that it is almost always more cost-effective to maintain natural wetlands than to drain or convert the wetlands to other (often marginal) uses, and then to try to provide the same services through structural control measures such as dams, embankments or water treatment facilities. In many cases it has also been found cost-effective to restore or even create wetlands to provide these functions rather than create expensive engineering structures.
An essential component of river basin management is knowledge of both current and future supply and demand upon water resources in a river basin, taking into consideration the possible impacts of climate change. Assessments of the resource need to focus on the human uses of water (such as irrigation, hydro-electricity and domestic or industrial water supply) as well as the ecological needs for water within different parts of a river basin. In this respect, water demands should not only be defined in terms of water quantity but also water quality. Ecological water demands are less obvious and more difficult to quantify and consequently have often been ignored or underestimated in terms of water demand. Ignoring such requirements may lead to major environmental and social problems such as collapse of fisheries or downstream saline intrusion. It is also important to recognize that the greatest damage to the environment may occur during extreme events rather than the average situation.
Socio-economic systems are constantly changing and therefore it is often necessary to develop a range of future demand scenarios and develop flexible sustainable use strategies which can be adapted to a range of circumstances. These problems should not be restricted to issues related to human activities but should also include ecological problems such as adaptation to reduced water supply or quality within certain ecosystems.
Water demand is mainly determined by the economic incentives for water and wetland use. Provision of incentives for practising environmentally sustainable water use can minimise the impacts on wetland areas. It is critically important to impose water prices that reflect the true cost of supplying water which will encourage the optimisation of water use, ensuring that in so doing there is recognition of the economic value of other services from wetlands. Environmentally unsound or inequitable incentives which are encouraging practices that are unsustainable need to be identified and removed.
Maintenance of water flows to maintain wetland functions
Wetland ecosystems depend on the maintenance of the natural water regimes such as flows, quantity and quality, temperature and timing to maintain their biodiversity, functions and values. The natural flow regime can be considered the most important variable that regulates the ecological integrity of riverine wetland ecosystems. In response to this, a number of countries have introduced legislation and guidelines to ensure adequate allocation of water to maintain natural wetland ecosystems.
A long-term strategy or plan should be established to manage water demand. Water allocations may be achieved in a variety of ways, including flow releases from reservoirs or restrictions to abstraction. Groundwater extractions to supplement stream flows to wetlands should only be supported where such extraction does not significantly impact on other water-dependent ecosystems and their values.
Flows should normally follow the natural regime as closely as possible. This may be achieved by relating the magnitude, duration and timing of releases or abstractions to flows in nearby unregulated reference catchments, which will require real-time monitoring. Special abstraction and release rules should be defined for droughts, floods, and emergency situations. Effective communication mechanisms should be established with all stakeholders for exchange of real-time information about releases and flow patterns. Management of water quality also needs to follow natural processes and mechanisms. Water releases from a reservoir may be of different quality to that of the natural river, so outlet structures should be designed to reduce such impacts. It is important to monitor compliance with water allocations and to ensure appropriate actions and responses. Where necessary, management strategies should be adapted in the light of monitoring and evaluation.
National policies, legal instruments, and a decision-making framework should be developed in order to promote the allocation of water to wetlands and to manage river basins. In most countries, this is still conducted according to administrative boundaries and not river basin boundaries. This can lead to measures for one site being nullified by activities elsewhere in the river basin.
Minimizing the impacts of land use and development projects
The land uses which can impact most significantly on rivers and wetlands are forestry, agriculture, mining, industry and urbanisation. Inappropriate forestry practices, especially in the upper watershed, can lead to increased soil erosion and reduced water retention capacity. Agricultural activities can also cause significant levels of pollutants from agro-chemicals and agricultural wastes. Upland agriculture through land clearing and subsequent operation can have a major negative impact on water quality and also lead to significant changes in flood and dry season flows. Lowland agriculture can lead to the drainage or conversion of floodplain wetlands leading to loss of biodiversity and natural functions and benefits. In many countries, irrigation is the main justification for abstracting water from rivers.
The impact of mining and industrial activities is mainly through the release of pollutants, some of which may be highly toxic. In addition, industrial activities or mining can instantly jeopardise entire river basins and all the associated wetlands and biodiversity through accidental spills. Urban areas have impacts through encroachment on wetlands, either directly or through associated infrastructure such as roads, ports, water supply and flood control. In addition the human populations they support lead to increased demands on resources and direct pollution.
The impact of existing land uses on river systems and associated wetlands needs to be monitored and controlled through the integration of regulations and guidelines on forestry, agricultural, mining or urban waste management. In many cases the implementation of such guidelines may lead to advantages for the land users themselves - for example, reforestation and good forest practices enhance the long-term timber yields; better agricultural practices reduce soil erosion and retain water for the dry season; better waste management improves quality of life and health for urban residents. However, there is normally a need to have a proper monitoring and enforcement mechanism to ensure effective use of the regulations.
Various mechanisms can be used to minimise environmental impacts. The first is environmental assessment and zoning, whereby the land use and natural resources of the river basin are surveyed, and the basin is zoned according to the different types of land use that may be permitted in each zone without having a significant impact on other zones or the river or wetland systems. A measure applicable to proposed new development projects is Environmental Impact Assessment (EIA). Cost-Benefit Analysis (CBA) is another tool to calculate the net impact of a project on the economic welfare of society by measuring all the costs and benefits of the project. Appropriate decision-making requires an analysis of the economic, social and environmental costs and benefits of water management plans through EIA and CBA. It is important that multidisciplinary teams conduct these processes and seek to engage the stakeholders at an early stage.
Water resource development projects are generally aimed at modifying the natural water flows in a river basin for purposes such as storing water through drought periods, preventing floods, transferring water to irrigated agricultural areas, industrial and domestic water supply, improving navigation and generating electricity. Such projects have frequently been developed through the construction of engineered structures such as dams, diversion canals, channelisation of rivers, flood levees, etc. Some of the most significant impacts of such projects include: reduction in river flows, blocking of pathways for migratory fish and other aquatic species, increased water pollution levels, disruption of timing of natural floods which maintain wetlands; reduction of sediment and other nutrient input into floodplain wetlands, drainage or permanent inundation of riverine wetlands, and salinisation of surface and groundwater.
In a number of cases it has been found that the social and economic losses as a result of the degradation of the downstream wetlands have been significantly greater than the benefits gained from the water development project itself.
In cases where a river basin is shared between two or more Contracting Parties, the Ramsar Convention's Article 5 makes it clear that these Parties are expected to cooperate in the management of such resources.
The UN Economic Commission for Europe has elaborated a specific Convention on the Protection and Use of Transboundary Watercourses and International Lakes (www.unece.org/env/water ).
Countries sharing a drainage basin are encouraged to establish frequent specific contacts in order to exchange information on the water resource and its management. Options for this include:
- establishing networks for monitoring and exchanging data on the water quality and quantity in the basin;
- a joint analysis of information on the quantity and type of water used for various purposes in each country;
- exchange of information on protection measures for groundwater, upper catchments and wetlands;
- sharing of information on structural and non-structural mechanisms for regulating flow for navigation and flood prevention.
The aim should be the preparation of technical reports on the river basin, including information on the needs of the local inhabitants in each part of the basin, as well as existing or potential problems in parts of the river basin that require separate or collaborative efforts to deal with them.
In October 2000, the European Union adopted an operational tool for a modern water policy: the "Water Framework Directive" (WFD) which aims to expand the scope of water protection to all waters, surface waters and groundwater, to achieve "good status" for all waters by a set deadline, to undertake water management based on river basin management, using a combined approach of emission limit values and quality standards in order to getting the prices right, the citizens involved more closely, and to streamline legislation.
These objectives must be integrated for each river basin, for which detailed objectives have to be established. Subsequently, an analysis of human impact is conducted so as to determine how far from the objectives each body of water is. If the full objective of the WFD is not attained, the Member State must identify additional measures to satisfy all established objectives. These might include stricter controls on polluting emissions from industry and agriculture, or urban waste sources.
The River Basin Management Plan will include the results of the above analysis, specify the river basin's characteristics, and provide a review of the impact of human activity on the status of waters in the basin, as well as an estimation of the effect of existing legislation to meet the "good quality" objectives, and a set of additional measures, where needed. An economic analysis of water use within the river basin must be carried out. This is to enable a rational discussion on the cost-effectiveness of the various possible measures. Member States are required to ensure that the price charged to water consumers reflects true costs, although in less-favoured areas, deviations from this may be possible so that basic services are provided at an affordable price.
It is essential that all interested parties are fully involved in preparatory discussions and in the preparation of the River Basin Management Plan. The greater the transparency in the establishment of objectives, imposition of measures, and reporting of standards, the greater the care Member States will take to implement the legislation in good faith. For more information, visit http://europa.eu.int/comm/environment/water/ .
The issues of transboundary river basin management are further detailed in the Ramsar Handbooks for the Wise Use of Wetlands which can be downloaded fromwww.ramsar.org/lib_handbooks_e.htm , notably in Volume 4 on Integrating wetland conservation and wise use into river basin management, and Volume 12 providing Guidelines for the allocation and management of water for maintaining the ecological functions of wetlands.