THE LOWER GREENSAND OF SOUTHERN ENGLAND: A SOUTHERN WATER PERSPECTIVE OF AQUIFER STORAGE AND RECOVERY (ASR)

摘要

The UK water industry has developed a number of successful artificial recharge schemes over the last twenty years in order to mitigate local resource/demand imbalances. However, unlike counterparts in North America, the application of ASR technology, in its true sense, has not been realised. Across the UK the potential for ASR is currently being explored in response to contemporary resource/environmental stresses and the encouragement of legislation to optimize existing water resource.rnSouthern Water supplies drinking water to over 2 million people in the south-east of England, of which approximately 70% is attained from Chalk aquifers. The demand/resource balance during the peak demand period (July and August) is a major issue for the company due to the Chalk's low storage capacity, heightened demand due to domestic garden watering/tourist influxes and the perceived impacts of climatic change. Consequently, Southern Water have initiated a major ASR capitol expenditure program with the long-term objective of developing an integrated multi-site ASR system, utilizing the Lower Cretaceous Lower Greensand at depth, along a significant section of the south coast of England.rnThe Lower Greensand along the coastal fringe is approximately 350m below ground level with essentially potable water (except for iron), which is about 6000 years old. At one site the unit has been proven to be 33m thick with an estimated permeability of 2.6 m/d.rnThe objective of this paper is to present a Southern Water perspective with regard to ASR for comparison and the dissemination of knowledge.