Estimating groundwater recharge through glacial till at Bacon Hall, Shropshire

A study was undertaken to obtain estimates for recharge to groundwater through glacial till. The work was carried out in support of the Hydrogeological Classification of Superficial Clays programme; a cofunded programme of research between BGS and the National Rivers Authority. Estimates were made using data from Bacon Hall, one of a series of sites used to monitor the Shropshire Groundwater Scheme. The sites are instrumented to measure the effect on soil moisture due to the pumping of wells, installed to enhance flows in the River Severn during dry periods. Each site consists of two piezometers, two neutron probe access tubes and a nest of tensiometers. A value of 167 mm of groundwater recharge was obtained for 1989-90. This is 28.8% of the annual rainfall. However, doubts about the hydrogeological system at the site and the interval at which data was available, both in time and depth raises questions about the-accuracy of the estimates.