Management of stream compensation for a large conjunctive use scheme, shropshire, UK

Abstract

The Shropshire Groundwater Scheme (SGS) is the largest conjunctive use scheme in the United Kingdom. The SGS operates in drought periods, pumping water from the Permo-Triassic Sandstone aquifer in Shropshire, England to regulate flows in the River Severn, alongside releases from conventional surface water reservoirs. This regulation protects the environment and increases the security of supply of major public water supply abstractions downstream. An important operational consideration is the impact SGS groundwater abstraction has on small streams that rise on the Shropshire Permo-Triassic Sandstone. Compensation boreholes have been installed to maintain flows during and after the operation of the SGS. This paper shows how a groundwater model of the East Shropshire Permo-Triassic Sandstone has been used to estimate the required level of compensation flows for recent climatic conditions to optimise the use of the SGS. The catchment wide conditions are included in this analysis by using the results of a large-scale surface water model of the River Severn. © 2009 Environment Agency. Journal compilation © 2009 CIWEM.