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Urban Wastewater Treatment Directive

Aims to protect the environment from the adverse effect of waste water.

The Urban Wastewater Treatment Directive regulates the collection and treatment of waste water from our homes and from industry.

It protects the environment from the negative effects of urban waste water and discharges from certain industrial sectors, such as food and drink processing plants. Some of these types of plants can produce waste that has a similar polluting effect as untreated sewage.

In the UK, the directive is implemented through the Urban Waste Water Treatment Regulations 1994.

The collection and treatment of waste water plays a vital part in the protection of public health, water resources and wildlife. The directive sets the standards for that collection and treatment. A sewerage system is provided for all urban areas above a specified size and that the collected sewage receives at least secondary (biological) treatment before it is discharged to the environment. Discharges from the sewerage systems are only allowed under storm conditions.

'Sensitive' are identified where sewage requires extra treatment before discharge. One type of sensitive area is 'eutrophic waters', where additional nutrients, mainly nitrogen or phosphorus, stimulate the growth of algae and other plants, damaging the natural environment. In these areas, larger sewage discharges must be treated to reduce their load of nutrients.

The directive also banned the disposal of sludge to sea from the end of 1998.