Water demand: the Austrian end-use study and conclusions for the future

Demographic and climate change will affect in the long term the total water consumption and therefore the planning and management of the related infrastructures. End-use studies provide information on water consumption and its influencing factors. However the availability of such detailed data is very limited. The research project carried out was based on total daily water consumption collected from 12 Austrian water supply areas for periods covering up to 10 years. The general data were complemented with high resolution measurements (ranging from day to 10 second intervals) of household consumption of residential buildings, semi-detached houses, single family homes, and weekend cottages as well as with meteorological data and comprehensive socio-economic and personal information. The major factors influencing residential household consumption are: demographic dynamics; age distribution; household size/family size; living conditions; and regional economic development. In the short term, water consumption is influenced by temperature, precipitation, day of the week and time. For residential consumption, these last parameters were found to be the main causes for the existing peak demands. Modernisation will lead to a further decrease of the indoor per capita water demand. The outdoor demand and its peaks are expected to increase due to climate change.