Developing and validating a decision support tool for media selection to mitigate drainage waters

•A DST was developed to select media for mitigation of drainage water.•The DST enables users to choose media specific to pollution and local conditions.•DST considers static/dynamic criteria to ensure environmental/logistics compliance.•The DST was tested using case studies in Ireland, Belgium and USA.•Consequent SWOT analysis found the DST to be systematic, flexible and transparent.