Evaluating stream rehabilitation projects: reasons not to, and approaches if you have to

Abstract

Over the last thirty years, the work of river engineers has shifted from the protection of physical and economic assets, to include the protection and enhancement of environmental assets. River engineers now work in multi-disciplinary teams that include biologists and social scientists. Environmental flow, and river rehabilitation projects are typical of this work. Unlike the well established engineering designs and practices of the past, there is now less confidence in the effectiveness of interventions, particularly where the outcomes involve animals, ecological functions, or imprecise ideas of ‘stream health’. Quite rightly, there is pressure to ‘evaluate’ the effectiveness of every publi..