Towards a specific definition of alpine water uses for accurate quantification

CALIANNO, MARTIN

Simposio; 6th IAHS-EGU International Symposium on Integrated Water Resources Management; 2014

Several integrated studies on water management have been conducted recently in the Alps. They combinewater resources and uses estimations in order to identify water scarcity issues that could occur inmountainous regions. Regarding the quantification of water resources availability, these works often rely onwell-known hydro-climatic science and exhaustive datasets. However, regarding water uses, directmeasurements are rare and researchers either depend on rough estimations given by water managers orcreate indirect datasets using proxies. Therefore, there is a strong need to correctly quantify water uses andto define a monitoring methodology in alpine regions. But before that, the definition and conceptual schemeof water use must be clarified.First, there is some confusion about the terms used in water management and scientific literature, like forinstance water 'needs', 'uses', 'demands', 'withdrawals' or 'consumption', but also between the terms'drinking', 'delivered' and 'household' waters. In this work we propose a methodical terminology to preciselydefine water uses in mountainous territories.Secondly, when water uses need to be quantified, many questions arise on how they are conceptualised,from a systemic approach. Which kind of water system should be considered: hydrological or human-impacted catchment? From which point of view should we apprehend water uses: preservation of waterresources or management of water use conflicts? What about the upstream-downstream issue? Whichspatial scale should be considered when uses have to be compared to other uses and water resources?Block-diagrams have been designed to answer these questions and to illustrate the different definitions ofalpine water uses. For each conceptual definition, scenarios of water balance between water uses andresources are computed. The most suitable systemic and spatial approaches capable of highlighting localalpine water shortages are then identified. This gives the first guidelines for a monitoring strategy.