Defra have launched the long awaited Biodiversity Metric 3.0 after the consultation and updates to the BETA BM2.0 version. The new BM3.0 guidance, the Calculation Tool and details of changes can be accessed here.

The good news for all River Condition Assessment surveyors is that no changes to the core RCA methodology have been made. The peer-reviewed MoRPh Pro and RCA River Type methods, guidance and supporting materials all provide the information needed to calculate the River Condition preliminary score and class values.

The really important news to note about the RCA approach in BM.3.0 is a new requirement in the final stage of assessment that takes account of the channel dimensions (as width to depth ratio) and hydrological connectivity in relation to restoration potential.

More information about how to consider connectivity in the final stage of River Condition Assessment for BM3.0 can be found here.