The impacts of channelisation on the geomorphology and ecology of the Kuils River, Western Cape, South Africa

Abstract

Urbanisation and storm water input in the Kuils River catchment changed the flow of the river from ephemeral to perennial. This led to flooding problems in the Kuilsrivier central business district. The river was channelised in 2000 to increase the carrying capacity of the channel and thus to reduce the flood risk. This study aims to monitor the impacts of channelisation on the geomorphology and ecology of the Kuils River. This was done by selecting representative study sites upstream, within and downstream of the channelised reach. The geomorphological and ecological characteristics of the river were recorded in detail with changes tracked over a year period incorporating channelisation activities and winter floods.