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Title: Less sensitive areas and candidate high natural dispersion areas in the North West region
Author: National Rivers Authority North West Region
Document Type: Monograph
Under Article 6 of the Urban Waste Water Treatment directive, member states are permitted to designate waters as less sensitive. Discharges into such waters from works serving a population equivalent of <150,000 are permitted to receive only primary treatment. To implement this part of the directive, the U.K. government introduced the concept of High Natural Dispersion Areas (HNDAs). The various regulators were asked to nominate discharges which in their opinion would satisfy the requirements for an HNDA. The underlying principal in the guidance notes from the DoE was that the receiving water would not benefit from the provision of secondary treatment on the discharge. It is significant that the process was discharge driven; the potential HNDAs, as approved by the DoE, are sea areas around a particular outfall, not entire lengths o f coast line. To justify the designation 'HNDA', the government requires that comprehensive studies' are carried out to demonstrate that limiting the treatment on qualifying discharges will not have an adverse impact on the receiving waters. The scope of these comprehensive studies is set out in considerable detail in a document published in February 1994 under the auspices of the Marine Pollution Monitoring Management Group. The onus of carrying out the comprehensive studies was placed on the discharger - in this case North West Water Ltd. The studies being undertaken by North West Water are focused on determining the impact of their discharges on near-field water quality, in particular the complex task of discriminating the differing effects of a primary or secondary treated effluent.
Publisher: National Rivers Authority
Publication Date: 1996
Publication Place: Warrington
Subject Keywords: Urban Waste Water Treatment DirectiveDirectives (European Union)Wastewater treatmentRegional planning
Geographic Keywords: EA North West
Extent: 6; + figures
Total file downloads: 258

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