The shortfall over the two-year period amounts to four months of missed rain. While February brought a welcome deluge with well above average rainfall, March so far has had significantly below the average.
The agency has asked water companies to submit detailed plans on how they intend to manage supplies. Few companies have so far applied to take extra water above their licensed level from rivers and groundwater in the summer but several have already been granted permission to take extra river water in the winter, using it to refill reservoirs.
Groundwater levels are drawn down more slowly than reservoirs' during dry periods but they also take longer to recover. Underground aquifers of porous rock provide more than two-thirds of tapwater in southern England, almost half the water for East Anglia and more than a third of the Thames valley area's supply. Nicholas SchoonReuse content