SEPA had a requirement under the Water Framework Directive to assess the morphological impacts of modifications to rivers. Within Scotland this is based on the MImAS assessment methodology and feeds into the operation of Controlled Activities Regulations and potentially into the type-specific Programmes of Measures. One of the key factors in the sensitivity of rivers is the geomorphic typology of the river, the classification of rivers based on their morphological attributes. GeoData implemented a river typology using geology, slope, confinement and sinuosity across the entire river network for Scotland. A suite of tools were developed in ArcGIS to process the Scottish river network and assigned a typology at reach level.