What is "rivpacs"

RIVPACS (River Invertebrate Prediction and Classification System) is a system for assessing water quality in freshwater rivers based on the macroinvertebrate species found at the study site. The species found at the reference sites collectively make up the species assemblage for that site and are the basis for a statistical comparison between reference sites and non-reference sites. Reference sites can be chosen and adjusted several ways. Usually they represent the best conditions within the region or area under study. Sometimes the reference site expectations are adjusted for degradation of the entire region by human impact.

'Pristine' freshwater sites are sampled to collect information on physical characteristics, chemistry and macroinvertebrates. This information is then used to predict what invertebrates are present from samples of physiochemistry from other sites.

This classification of freshwater sites based on the macroinvertebrate fauna was first derived in 1977. Since then it has been developed and updated with addition of a wider range of freshwater sites.