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الأربعاء، 9 نوفمبر 2016

Non-renewable groundwater resources - unesdoc - Unesco ...



NON-RENEWABLE GROUNDWATER
RESOURCES



EDITORS
Stephen Foster and Daniel P. Loucks
COORDINATORS
Raya Stephan, Alice Aureli and Karin Kemper
CO-SPONSORS
World Bank-GW.MATE 

Published in 2006 by the United Nations Educational, Scientific and Cultural Organization
7, Place de Fontenoy, 75352 Paris 07 SP (France)
Composed by Marina Rubio, 93200 Saint-Denis
© UNESCO 2006
SC-2007/WS/4


From UNESCO 

  Hydrogeology is a relatively young discipline and therefore the knowledge on the characteristics and dynamics of different types of aquifer is still not yet fully achieved.

  It is only very recently that groundwater experts have become aware of how climatic changes that took place during the various geological periods actually modified and shaped the earth and consequently the aquifer systems. Past climatic conditions made it possible to store vast groundwater resources in deep underground reservoirs. Some of these systems are the heritage of previous, more humid climatic conditions that existed thousands of years ago, and some of them are located in regions that today suffer from arid or hyper-arid climatic conditions and receive little contemporary natural recharge. The age of the water contained in these aquifers is therefore so old that it has inspired the use of terminology borrowed from paleontology; as a result these aquifers bear the nickname 'Fossil Aquifers'.

   In arid zones groundwater is a source of life and as such it is difficult to find a balance between preservation and use. This is made more difficult when the necessary data required to study these systems is inaccessible, and even more complicated when such systems are transboundary and therefore shared between two or more countries. 

  Considering the complexity of the issue, and its political sensitivity, the UNESCO International Hydrological Programme (IHP) and the World Bank decided to call upon international experts to support the preparation of a text that could provide valuable indications on the sustainable use and management of these water resources. 

  This publication intends to provide a contribution not only towards the development of an improved knowledge base in the field of hydrogeology, but also to the sustainable management of groundwater resources in different regions of the world. In particular it aims to provide decision-makers with the relevant scientific information

  UNESCO's IHP has been dealing with the issue of non-renewable groundwater resources since 1996. Indeed, in 1996 during its 12th session, the Intergovernmental Council of UNESCO's International Hydrological Programme, adopted Resolution XII-8 on the ‘Study of fossil groundwater in Sub-Saharan and Saharan Africa’ (Appendix 1). In this Resolution, the IHP Intergovernmental Council, considering that aquifer systems are often the main source of fresh water in arid and semi-arid zones, recommended to improve knowledge about Fossil Groundwater in Preface Sub-Saharan and Saharan Africa. Since then, UNESCO-IHP has undertaken several activities such as the International Conference on ‘Regional Aquifer Systems in Arid Zones – Managing non-renewable resources’ (Tripoli, 21-25 November 1999). The Conference marked a milestone in the review, discussion and analysis of the emerging concept of planned groundwater mining. One of the direct achievements of the Conference was the Tripoli Statement (Appendix 2) which recognized that in many arid countries the controlled and carefully regulated mining of non-renewable groundwater resources could provide an opportunity and a challenge for their social and economic development. 

  It is within this framework that UNESCO IHP in cooperation with the World Bank/ GW-MATE that UNESCO-IHP organized a seminar on the ‘Socially-Sustainable Management of Non renewable groundwater resources’ in Paris in September 2002. As a result of this meeting guidelines were formulated by a group of experts and the publication was initiated. It should be pointed out here that the authors contributed to this title under their own personal capacity. They were selected for their knowledge and expertise both in this specific field as well as within a specific region.

  The case studies as well as the data and the indications provided in the chapters, refer mainly to situations existing in arid and semi-arid regions, although non-renewable groundwater resources are also found in humid and permafrost regions. 

  One such example from a temperate climate, is the Albian-Neocomian aquifer system located in France, in the Parisian basin, composed of two reservoirs, the Albian and the Neocomian, which are hydraulically linked. According to the indications provided by the French Agency ‘Agence de l'Eau Seine-Normandie’, the system covers 84,000 km2 and its total estimated reserves are around 655 billion cubic meters. The Albian aquifer has very original characteristics: total protection against surface pollution, high reserves in water, and a very low natural recharge compared to its total volume. The Neocomian aquifer is still not well known, but seems to present similar characteristics. The Albian aquifer has been developed since the middle of the nineteenth century. The result was a drop in the water table of 80 meters. Public authorities reacted and in 1935 adopted a regulation imposing a licensing regime on all drillings of more than 80 meters depth in the Parisian basin. The Neocomian aquifer was developed only recently (in 1982).

  Today the Albian-Neocomian system is considered an important strategic resource (Agence de l'Eau Seine-Normandie, www.eau-seine-normandie.fr/index.php), exploited mainly for drinking water purposes. In 2003, the ‘Schéma Directeur d'Aménagement et de gestion des eaux du bassin Seine-Normandie’ was amended in order to maintain the emergency function of the system (arrêté préfectoral n°2003-248, 24 February 2003). Indications concerning the total annual volume of water that can be extracted from the system in case of emergency are carefully provided.

  Some of the aquifer systems considered in this monograph are transboundary, as already mentioned. Their management creates specific problems. The sharing of these resources implies equity of influences from all parties concerned, co-operation in development policies and plans and ideally joint monitoring. This particular issue has been considered and developed in the draft articles on the law of transboundary aquifers, in preparation since 2003 at the UN International Law Commission, with the scientific support of UNESCO-IHP.

   They are also part of the inventory of transboundary aquifers around the world initiated by UNESCO-IHP since 2000 under its Internationally Shared Aquifer Resources Management project (ISARM). The aim of the project is to reach the sustainable management of transboundary aquifers. 

   Finally, just recently, UNESCO-IHP together with WMO submitted the chapter on the status of the resources in the second UN World Water Development Report (March 2006) recommending to decision makers and water scientists to pay greater attention to non-renewable groundwater resources.

   We hope that this monograph could be useful to decision makers in addressing the environmentally and socially sustainable policies that should be set up as long as due consideration is given to the assessment and management modalities for non-renewable resources. 

Alice Aureli 
Responsible for the Groundwater Resources Activities
International Hydrological Program Division of Water Sciences UNESCO

Raya Marina Stephan 
Lawyer 
Consultant 
International Hydrological Program Division of Water Sciences UNESCO 


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