Estimating the amount of cold water wastage in UK households

Current and future water demand pressures arising from inadequate supplies and forecasts of increased population in the UK have prompted the government and other stakeholders to set up strategies that will ensure sustainable water supplies. Demand-side management strategies are one of the key priorities being pursued and the water regulator, Ofwat, has set a target of 13% reduction from 2010 levels of per capita household water consumption in England and Wales by 2030. This paper reports on estimated water wastage in UK households resulting from users waiting for water to reach a sufficiently warm temperature when using a hot water outlet (including kitchen sinks, showers and hand wash basins). It is estimated that, on average, 10% of the daily average per capita water consumption in UK households is wasted in this way. Possible means of reducing this waste are identified and a recommendation is made that boilers should carry a water efficiency rating in addition to the standard energy efficiency rating.