The Development of a “BMP Matrix” for Mitigation Options in NW European Catchments

A comprehensive review of Best Management Practices (BMPs) was undertaken within the New‑Harmonica project to ensure mitigation measures for nitrogen (N) and phosphorus (P) losses align with recent scientific advances and the specific conditions of four NW European catchments. Seventy‑two BMP options were evaluated, considering trade‑offs and synergies with gaseous emissions and soil carbon sequestration. Catchment groups then developed scenario-based shortlists informed by stakeholder consultations on feasibility and effectiveness. While P‑focused measures such as buffer strips and wetlands remain central in many catchments, N mitigation emphasises source control and improved manure management. The resulting BMP Options Matrix provides a flexible tool for ongoing modelling and adaptation. Future work should address BMP longevity and support stakeholders through decision-support tools that aid targeted measure selection.