Watershed planning for urbanization to avoid undesirable stream outcomes

Abstract

Watershed planning is presented as an advanced approach todevelopment. It is imperative that the impacts of urban developmenton water resources be set in the context of integrating human activity into landscape form and ecological function. Preliminary results from the Urbanization Issues group of the Ecoresearch project arepresented. The three areas of focus are: unintended outcomes of channel changes, the influence of off-floodplain development on non-point source surface water pollution, and innovation in the development process. Our studies were conducted in relation to proposed development in the headwaters of Laurel Creek. Virtually all Laurel Creek through the developed portion of Waterloo has had channel modifications. This led to many undesirable outcomes which were unexpected, or whose importance were not appreciated until later stages of development. Development in the watershed beyond the floodplain can also have significant adverse impacts on stream quality. These impacts may be especially large in typical suburban form with large areas of private lawn in relatively affluent neighbourhoods. We propose that in addition to maintaining channel integrity, innovative approaches to storm water management are required to protect ecological features. Attitudes to innovation in development were explored with planners and developers. It was found that controls of ecological innovations are complex. This suggested that consensus-based decision making for development has the best potential for facilitatingnecessary changes. Waterloo is undertaking development of the headwaters of Laurel Creek in line with recent Government of Ontario guidelines, using a round-table approach. These studies highlight somefundamental characteristics of a watershed approach to planning which should minimize unintended, undesirable stream outcomes. © 1996 Taylor & Francis Group, LLC.