Types of water pollution
The different types of water pollution are explained below.
Point source pollution
Pollution from a single identifiable source, such as a drain or sewer, is known as 'point source' pollution. These discharges are usually regulated by permits that have strict conditions to minimise the effects on the receiving water environment. Failure to meet permit conditions is an offence which can result in legal action by the environmental regulator. Despite being legal some of these permits need to be tightened to improve to meet new water quality standards.
Examples of these are discharges from sewage treatment works and industry.
Diffuse pollutionDiffuse pollution is dispersed and widespread with no single point of entry into the water environment. It is the accumulated effect of many contaminants sources over a large area. Rainfall then washes these contaminants into rivers, beaches or ground water. Whilst the impacts may be individually small, when added together they can be damaging. These impacts have increased as agriculture has intensified and as we have built more roads and houses. More urbanisation also impacts on the natural flow of rivers and streams as rainfall tends to run off faster.
Diffuse pollution results from the way we live our lives, use land and manage soil. Unlike point source discharges we cannot easily control diffuse pollution by issuing licences or permits. Due to the widespread and dispersed nature of diffuse pollution it is very difficult to identify who is responsible and we have to control this in other ways. There are some real challenges regarding how we can address diffuse pollution. The ConnectRight campaign is working to improve knowledge and get cooperation from many organisations and individuals.
Examples of diffuse pollution include run off agricultural fields or seepage from abandoned mine workings. Pollution in urban areas is often diffuse - road runoff, misconnections, litter, old deposits of polluted sediment and discharges from industrial areas all damage ecosystems in rivers, streams and ponds. and make our urban areas less pleasant places to live and work in.