This classification method enables the assessment of invertebrates in rivers in relation to general degradation, including organic pollution. Walley, 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.
The method statement published in December 2014 for the second river basin planning cycle has been amended and re-published for the third cycle to reflect changes to the web platform for RICT, which is now hosted by the Freshwater Biological Association.
