This dataset is a subset of "WFD Classification Status Cycle 2" and contains classification data for benthic invertebrates in rivers. Benthic invertebrates can be used to indicate the ecological status of a river. Data on number of taxa (NTAXA) and average score per taxa (ASPT) is run through the River Invertebrate Classification Tool (RICT). Bias values are applied to these scores to account for identification and sample sorting errors. The actual (observed) scores are compared with a predicted score (reflecting a river in pristine condition). The comparison of the observed to expected scores is known as an Ecological Quality Ratio (EQR). Means of the annual EQRs are used to produce a benthic invertebrate classification (High, Good, Moderate, Poor, Bad) of the monitoring site for Water Framework Directive (WFD) purposes. The data is then run through another tool called VISCOUS to produce a water body level classification. Attribution statement: © Environment Agency copyright and/or database right 2015. All rights reserved.