Sustainable water management and shortage risk on small islands

• Main Author: Chiron, Thomas
• Other Authors: Littoral, Environnement, Télédétection, Géomatique (LETG - Brest), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN), Université de Nantes (UN)-Université de Nantes (UN), Université de Bretagne occidentale - Brest, Louis Brigand
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2007
• Subjects: small islands; freshwater resources; drought; shortage; risk management; îles; ressource en eau; sécheresse; pénurie; gestion du risque; [SHS.GEO]Humanities and Social Sciences/Geography; Breton Island
• Online Access: https://theses.hal.science/tel-00281315; https://theses.hal.science/tel-00281315/document; https://theses.hal.science/tel-00281315/file/TheseChiron.pdf

Freshwater resources of small islands as Breton islands are naturally restricted by hydroclimatic and hydromorphological conditions. The hypothesis that lack of freshwater could limit their economic development, namely touristic development, has often been mentioned in the bibliography. Results of investigations in archives and interviews of “local memories” underline how much water management constituted a main topic in Breton island history. That is testified by many references to the question, namely relative to conflicts of uses. Nowadays, freshwater question seems to be secondary to managers and islanders. For the last four decades, hydraulic equipments had actually been considerably improved in order to supply the increasing water demand due to tourism activity and the improvement of living standards. Technico-economic analysis shows that such a structural effort has led to hydraulic oversizing and a relative overinvestment in comparison with regional and national figures. Nevertheless summer water shortage risk is not stemed yet for some islands that still remain vulnerable to the most important droughts, as in 2005 when Belle-Île faced its fourth water shortage since the 1950's. While integrating natural, human and infrastructural parameters, the proposed retrospective and prospective assesment of water shortage risk constitutes a new approach to analyse the sustainability of water policy on small islands, giving managers figures to make decisions. Les contextes hydroclimatiques et hydromorphologiques qui caractérisent les petites îles, à l'instar des îles bretonnes, sont autant de contraintes naturelles qui limitent physiquement leurs ressources endogènes en eau. La bibliographie a souvent émis l'hypothèse selon laquelle l'eau pourrait justement constituer un frein à leur développement, surtout touristique. Dans les cas bretons, les recherches en archives et les témoignages des « mémoires locales » rappellent combien l'eau fut une préoccupation insulaire majeure : c'est toute leur histoire moderne qui ...