Streamflow Responses To Rainfall Events In Wetland, Urban And Agricultural Environments

Abstract

<p> Through the use of unit hydrographs this paper demonstrates the effect of land uses on the stream discharge of three watersheds located in Southern Ontario. The watersheds represent urban, agricultural and wetland environments. The three different environments each demonstrate different responses to a unit magnitude of uniformly distributed precipitation. </p> <p> The rainfall events occurred during September and October 1981 and 1986. Three durations of events, six, twelve and twenty-four hours, are studied. </p> <p> The paper demonstrates that an urban watershed experiences a greater magnitude of peak discharge and faster response time than either of the other two studied watersheds. The unit hydrograph resulting from a wetland showed that the wetland watershed was an important regulator of streamflow. </p> <p> Special emphasis were placed on the urbanization of agricultural lands as this is the most applicable land use change currently occurring in Southern Ontario.The results from this study will be useful when assessing the magnitude of the potential runoff problem when these agricultural watersheds are urbanized. </p>