This document presents research on approaches to mitigate pollution from the herbicide MCPA (2-methyl-4-chloro-phenoxyacetic acid) in water catchments used as drinking water sources. The research monitored MCPA concentrations spatially and temporally in an agricultural catchment in Ireland that supplies drinking water. Key findings include: MCPA concentrations exceeded drinking water limits and persisted in the system; concentrations increased downstream; and concentrations correlated positively with improved grassland and negatively with rough grazing land use. The research demonstrates the need for enhanced monitoring and questions the sustainability of certain land uses like improved grassland near drinking water sources.