Session FT 5.09
Groundwater and risk management coping with water scarcity. Climate Change and emergency situations
International Groundwater Resources Assessment Centre (IGRAC)
Research Group of Water Balance and its future expectation on alluvial fan (WEF), Japan
The session had the intention to highlight and discuss groundwater in the context of risk management, mainly from the perspective of groundwater availability. This placed the focus on water scarcity, either steadily developing in poorly water-endowed environments under human and/or climatic pressure, or caused by disasters. The session assessed and discussed approaches on how to control or mitigate such water scarcity conditions. Emphasis was put on technical and scientific rather than on socio-economic and institutional aspects.
- Small-scale recharge dams may be very effective to conserve water and have proven to generate clear benefits in the immediate surroundings, at affordable costs. But even beyond the immediate target area, they may have positive side-effects downstream by maintaining a baseflow in the watercourse and by reducing devastating floods.
- Floods and other natural catastrophic events can be seen as a warning to be prepared for next similar events. Preparedness may be achieved by setting up risk reduction strategies and empowering the role of strategic fresh groundwater resources to be mobilized during emergency situations (UNESCO-GWES)
- The identification and characterization of groundwater resources that are well-protected against or resilient to degradation in water quantity and quality constitute indispensable preparatory steps towards adequate water resources management in emergency situations.
- Groundwater resources are important, but often exposed to natural and anthropogenic degradation risks. Therefore, their exploitation should be accompanied by adequate protection and management.
- Proper attention should be paid to the key role groundwater may play in managing water-related risks, owing to its buffering capacity and high resilience.
- Transboundary aquifers require additional efforts in exchanging information and in reaching consensus on risk-control measures to be taken.
- Steadily increasing water demands in the many water-scarce regions of the world call for action, either augmenting usable water resources or reducing water use, or both.
- Water scarcity requires controlling groundwater abstraction, using regulatory measures, water saving techniques, incentives and/or awareness programmes.
- Artificial groundwater recharge using sand dams - as pioneered in Kenya - appear to be an affordable and effective approach to augmenting water resources in water-scarce regions.
- Change to dryer climatic conditions would reduce groundwater availability of the world’s dry regions disproportionally. This problem deserves special attention and targeted action.
- In Japan’s alluvial fan zones, integrated management of groundwater resources is indispensable for human well-being, to counteract observed environmental stress due to climate change and human activities.
- As the 2002 catastrophic flood of the Labe River in Czech Republic demonstrates, it is of crucial importance in disaster-prone areas to identify and study groundwater resources to be used for emergency water supplies.
- After a tsunami, attention for rehabilitation of water supplies and affected aquifers is an important step towards quick normalization of the lives of the affected population, as shown in Tamil Nadu.
- Groundwater has to be considered as an integral part of the hydrological cycle and needs to be taken into account in any integrated water resources management plan. To enable this, special attention should be given to the quantification of aquifer inflows and outflows (both water and solutes), including submarine discharges and possible sea water intrusions.
Orientations for action
- Replication of the sand dam projects as developed in Kenya to generate benefits in other similar areas is unlikely to occur spontaneously but needs to be organized. Feasibility of a pilot project in which different countries in the East African region participate should be investigated.
- Risk management related to groundwater is hampered by the lack of crucial information on groundwater worldwide. This lack of information should be combated by establishing or improving permanent groundwater information systems (in particular assessment programmes, monitoring systems and databases) at different levels (sub-national, national and regional). Concerted action of the international groundwater community is needed to convince governments and groundwater mandated national organisations of the need for developing and maintaining such information systems.
- The International Groundwater Resources Assessment Centre (IGRAC) has been established in particular for improving the world community’s access to existing world-wide groundwater information and experience, with the objective to unlock the potentially huge benefits this may produce. It does so by developing an international internet based platform for sharing globally relevant groundwater information and experience. Efforts are needed to acquire the international cooperation and the financial support needed to develop IGRAC’s functions optimally.
- Worldwide mapping of vulnerable areas and hot spots for natural hazards and disasters is required to assess regional priorities for developing risk reduction strategies.
Local Actions presented
Kenya sand dams
Mr Jeroen Aerts, Free University Amsterdam
During the last ten years, a Kenyan NGO called SASOL has implemented a methodology to mitigate droughts by developing so-called 'sand dams'. These low-cost dams are constructed through community inputs. The success of these dams as an affordable and effective technique for artificial recharge of groundwater resources triggers a challenge of upscaling and transferring this local expertise to other areas.
River Toyohiragawa alluvial fan
Mr Hu Sung Gi, WEF Japan
The alluvial fan of River Toyohiragawa is situated in the central part of of Sapporo city area and has a population of over 1 million. Groundwater of the fan head is extremely important for water supply in this area. However, the groundwater system is strongly affected by pressures of human activities and climate change. A study is carried out to enable integrated management of this complex water resources system, to safeguard it for the next generations.
Tsunami and the Indian coastal groundwater and emergency remediation strategy
Mr Bhanu Neupane, UNESCO New Delhi
After the December 2005 tsunami, action was undertaken in Tamil Nadu (India) to inventory and monitor fresh groundwater resources and to define how to rehabilitate water supply systems and affected aquifers. This action was carried out with a large degree of community involvement. Such an approach can be replicated in similar emergency situations for the benefit of quick normalization of the lives of the affected population.
Groundwater for emergency situation (GWES) with respect to the catastrophic flood on the Labe (Elbe) River in the Czech Republic
Mr Jan Šilar, Prof. Emeritus, Charles University (Prague)
Floods in the Czech Republic in 1997, 1998 and 2002 resulted in a collapse of water supply systems and stimulated a project to find substitution for damaged water resources. In the valley of the Labe (Elbe) river in its lower reaches in North Bohemia, hydrogeological and isotope-hydrology data of the artesian aquifers in the Cretaceous basin were evaluated. The methodology consisted in using groundwater dating for determining the vulnerability of the aquifers.