Natural England engaged Westcountry Rivers Limited (the commercial arm of Westcountry Rivers Trust) to develop a method for catchment-wide pollution risk and source apportionment assessments.

The objective of these assessments was to undertake a detailed review of the available evidence and to use visualisation techniques to present this information so it is more accessible and therefore better able to inform the delivery of future catchment management initiatives.

In order to deliver the Catchment Investigations, Westcountry Rivers Trust developed a scalable methodology that can be adapted to meet the specific requirements of any study catchment.

The investigations also provide targeted and fully costed intervention strategies for each of the study catchments, which are designed to achieve the most significant improvements in water quality using the most cost‐effective and resource efficient approach.

The reports produced are intended to be working documents that become a shared resource used by local groups to deliver tangible measures on the ground.