Protecting Water Resources and Health by Protecting the Environment: A Case Study

Abstract

The effluent from growing populations and the increasing use and disposal of chemicals into the environment can overwhelm ecosystems’ natural ability to absorb and treat waste. Historically, the approach to protecting the environment from sewage discharged into it is to collect and treat it. Similarly water taken from sources used for public water supply is treated to protect populations from the effects of untreated or diffuse pollution. Both approaches have proved successful and will continue to play an essential role in protecting ecosystems and public health. However, if the cost of treatment and the associated carbon footprint of these treatment processes are to be controlled, a complementary approach is needed to protecting ecosystems and the water extracted from them for public supply. Catchment management, a means of minimising diffuse pollution, and therefore the need for more complex treatment, is being used by Wessex Water and other water companies to drive down the cost and carbon footprint of more expensive and energy-intensive treatment processes needed to meet the demands of tightening health and environmental standards. The impact of this approach in a number of defined catchments in the Wessex Water region has been studied over the last three years. Whilst the catchment management approach has demonstrated that a reduction in the residual levels of nitrogen in the soil can be achieved without affecting a farm's output, it is not yet clear whether the impact of these changes has reached the water supply aquifer. However, in surface waters where travel times are much faster, immediate impacts have been achieved, particularly a reduction in the detection of pesticides.