Domestic per Capita Water Consumption in South West England

WHEN THE Component Method is applied to produce a forecast of future water demand, particular attention must be paid to the unmeasured consumption. This component consists largely of domestic water demand and takes into account the major water uses within the home. A knowledge is therefore required of the ownership of water-using appliances, the volumes of water involved and the frequency of use. These data are best obtained by the metering of individual households, supplemented by questionnaire surveys and the completion of diaries for each major element of water use. Such a survey was carried out by South West Water over a 13-month period during 1977-78. Subsequent updating, which has included further surveys of appliance ownership in the original sample of households and of the capacities of individual appliances, has shown that domestic per capita consumption has increased from 113.4 1/hd/d in 1977 to 131.6 1/hd/d in 1985.