What we expectLate autumn is usually when UK groundwater levels start to rise again. Plant growth slows at this time of year, and as the plants are taking up less water, soils 'wet up' so that rain can once again infiltrate down to replenish aquifers.
Across much of the UK the pattern has been different this year. Rainfall was lower than usual last winter, so groundwater levels did not rise as expected. Droughts were predicted and eventually declared in many areas. Exceptional rainfall between April and July then ended the drought, causing remarkable rises in groundwater levels. Groundwater hydrographs were practically inverted across the winter-spring-summer 2012 period, as illustrated by the example in the image.
An incisive overview of the hydrological events of this period has been published by CEH: "An overview of the 2010-12 drought and its dramatic termination".