The unaccounted costs of conventional urban development: protecting stream systems in an age of urban sprawl (10793)
Stream restoration is big business throughout Australia and internationally but recent findings suggest that channel construction does not necessarily lead to improved aquatic ecosystems. In light of these findings, and recent evidence on the drivers of urban induced geomorphic change, this paper compares channel construction to catchment-scale opportunities. Consideration is given to each approach relative to cost, ecological goals, and flood attenuation. Channel construction approaches, involving earth works and protection such as rock, for example, can readily address flood concerns for the immediate surrounds but hydraulically extend the cities drainage network and transfer floodwaters to major centres. Catchment-scale approaches, such as through stormwater harvesting and infiltration, or floodplain engagement, on the other hand, may require more space but also have more extensive benefits along the stream network. Catchment-scale approaches to reducing the stressors on urban streams appear necessary if complex and dynamic streams that better support aquatic ecosystems are desired. Quantitative evaluation of these approaches is required to assess the range of benefits provided by catchment-scale approaches to protecting urban streams.