Isotope Hydrology Section
IAEA Programme on Water Resources (2004-2005)
Rationale:
The 1992 United Nations Earth Summit in Rio de Janeiro concluded that “the holistic management of freshwater as a finite and vulnerable resource, and the integration of sectoral water plans and programmes within the framework of national economic and social policy, are of paramount importance for action in the 1990's and beyond”. The Commission on Sustainable Development (CSD) in its second (1994) and sixth (1998) sessions, and the 1997 Special Session of the UN General Assembly called for a concerted effort to develop more integrated approaches to water management and for a stronger focus on the needs of poor people and developing nations. Reflecting upon the increased water demands in the future, the World Water Vision, launched at the Second World Water Forum in The Hague in March 2000, states that “this increase in water withdrawals implies that water stress will increase significantly in 60% of the world, including large parts of Africa, Asia and Latin America. Will this lead to more frequent and more serious water crises? Assuming business as usual, yes”. Through the sustainable use of water resources basic needs can be met, vulnerabilities can be reduced, and improved and secure access to water can be created. Correct policy decisions necessarily depend upon th e quality of knowledge available to decision makers, and the complexity of water issues creates a need for policies that maintain and extend the knowledge base. Isotope and related nuclear techniques are effective and unique tools for obtaining hydrologic information for a broad range of water resource management issues. The Agency is the lead UN agency in this area and provides the basic means of using these techniques in the form of global reference data and isotope reference materials. A wider use of isotope hydrology in the developing Member States for water resources development and management requires the development of technology and human resources as well as financial assistance. The water resources programme of the Agency aims to fulfil these needs. As isotope techniques are more effective when used as an integral part of hydrologic practices, the programme also aims to co-ordinate its activities with other national and international organizations active in the water sector. In particular, collaborative programmes with the WMO, UNESCO, the World Bank, FAO and UNEP are presently active and are to be strengthened in the future. The Agency's continued involvement in extending the use of isotope hydrology has been duly recognized by the Member States through a number of General Conference resolutions, the most recent being GC (45)/RES/12B. Substantial Member State interest in the programme is indicated also by an increasing number of requests for assistance through the technical co-operation programme.
Sub-programme G.1. Isotope Methodologies for the Protection and Management of Surface Water Groundwater and Geothermal Resources
Rationale: More than 50% of the fresh water used for drinking and irrigation worldwide is obtained from aquifers. Groundwater development in many countries has been relatively unrestricted and has produced a variety of adverse effects, particularly in areas where groundwater is in fact fossil, or non - renewable, with low rates of replenishment under present day climate conditions. In many cases, groundwater from non-renewable aquifers is being used to increase food production, making both the water supply and food production unsustainable. In coastal aquifers, groundwater use needs to be carefully balanced to avoid the negative effects of seawater intrusion but with maximum exploitation of fresh groundwater. Surface water resources are also being exploited with dams and reservoirs to meet present water and energy demands and are prone to pollution from waste water discharge and irrigation runoff. Pollution has also adversely affected many groundwater reservoirs. Many of the Member States in Latin America, Africa and Asia are increasingly exploiting geothermal resources for meeting their energy needs. Planners and managers in Member States need an improved knowledge base of hydrological information to make appropriate decisions for the sustainable management of water and geothermal resources. Co-ordinated research, while helping to develop, test and adapt techniques under a variety of hydrogeological conditions, strengthens the capacity of Member State institutions for research and implementation of isotope applications. The Agency's research contracts programme provides an excellent mechanism for bringing together Member State institutions and other UN agencies to jointly study issues of international concern that are beyond the scope of national research institutions.
Project G.1.01: Development and transfer of isotope methodologies for groundwater management
Project G.1.02: Assistance to Member States for development and management of geothermal resources
Project G.1.03: Development of analytical tools for dam leakage and reservoir sedimentation
Project G.1.04: Exchange of information and training in isotope hydrology
Project G.1.05: Isotope methods for the assessment of groundwater sustainability
Sub-programme G.2. Reference Isotope Data and Analysis for Hydrological Applications
Rationale: The use and development of isotope applications for water resources management requires isotope data for various components of the hydrologic cycle. These data, termed global reference data, and the ability to measure isotope compositions are necessary for the Member States to use and integrate isotope methods into their water resources management practices. The primary components of the earth's hydrological cycle are precipitation, river flow, and evaporation/transpiration from vegetation. The Agency has initiated and maintained (jointly with WMO) a Global Network of Isotopes in Precipitation (GNIP) for the last 40 years. Continued isotopic monitoring of precipitation provides an ability to understand the processes influencing the amount and geographical distribution of precipitation, as well as a baseline input function for other hydrological applications. Runoff accounts for about 35% of precipitation losses from the continents. Isotope monitoring of large river systems provides reference data as an integrated output function for continental runoff and water balance studies and for the analysis of climate and environmental change in large river basins. A network of isotope monitoring stations for rivers is necessary to maximize and broaden the use of reference isotope data for water resources assessment and management. Evaporation and transpiration account for about 65% of precipitation losses on the continents. A global survey of isotope contents of air moisture and leaf water on different types of vegetation may provide an effective tool for improving water balance calculations and assessment of climate change and development impacts. Although critical to the practice of isotope hydrology, these reference data are not collected on a global scale and disseminated in the public domain by any other institution. The role of Agency in providing global isotopic data is well recognized by the isotope hydrology community in both the developed and the developing Member States. Member States have requested the Agency to strengthen their analytical capacity. This requires assistance in the form of equipment as well as an assurance of the quality of measurements being made. The Agency, as an impartial body, is also the primary source of reference materials for isotope measurements, and the main co-ordinator for inter-laboratory comparisons in both developing and developed Member States. The capabilities of the Agency's Isotope Hydrology Laboratory will be enhanced by the addition of a facility for the measurement of helium isotopes, which would allow age measurement of young waters with low tritium content. Building upon the outcomes of project activities in the 2002–2003 cycle, the analytical capability of Member State laboratories will continue to be improved through capacity building and information dissemination activities.
Project G.2.01: Collection and use of isotope data for precipitation and runoff
Project G.2.02: Strengthening Member State capability for isotope measurements
Project G.2.03: Isotope methods for the study of water and carbon cycle dynamics in the atmosphere and biosphere
Project G.2.04: Development of helium isotope applications for water resources management
