A tool for assessing the impact of modifications to a river on river morphology and associated ecological quality. The inputs to the tool are:
Each type of modification has a particular impact rating for each channel type, which is multiplied by the length of channel affected, and scaled to the reach assessment length:
where M is the modification impact rating, L is the length of the modification, and R is the length of the reach being assessed. See Gilvear and Jefferies in J. Holden (2012) p. 360.