Skip to main content

Vocabulary Term Details

River Quality Objectives

Definition (

The RQO classification was used for planning water quality improvements until 2006 when the scheme ended. RQOs were assigned to all significantly sized rivers (based on river flow). RQOs were based on the River Ecosystem (RE) Classification Scheme which was introduced in 1994 to replace the National Water Council's methodology. The RE system consists of five classes (1-5) and is based on the same determinands used in GQA chemistry assessment of BOD, ammonia and dissolved oxygen but also includes the additional determinands of (free (or un-ionised) ammonia, pH, hardness, dissolved copper and total zinc) that reflect the requirements of a river ecosystem. (EA)

Preferred Units: N/A

Scope Note:

Broader TermsNarrower TermsRelated Terms
Environmental standards
N/AEnvironment Agency
Environmental quality
Pollutant load

This term is used for the following terms: 

Approved Date

Items having a keyword or observed-property relationship to this subject term

Click here to give feedback on this term or suggest an update.