This classification method enables the assessment of invertebrates in rivers in relation to general degradation, including organic pollution. Whalley, Hawkes, Paisley & Trigg (WHPT) metrics replace the Biological Monitoring Working Party (BMWP) metrics used for status classifications in the first river basin planning cycle.
The River Invertebrate Classification Tool (RICT) is used to contextualize WHPT scores, by using a River Invertebrate Prediction And Classification System (RIVPACS) model to predict site specific reference values and provide a WFD compliant probabilistic classification.
NB There are two amendments to the WHPT ASP EQR boundaries in the July method statement. These have been revised in the December version.