Bedload sediment transport and morphologic data in semi-alluvial rivers conditioned by urbanization and stormwater management

Watershed urbanization and stormwater management (SWM) alter the hydrologic and geomorphologic processes of rivers. This purpose of this study is to characterize the bedload sediment transport regime of semi-alluvial gravel-bed rivers, and how it is affected by watershed urbanization and common SWM strategies. Data was collected from three rivers in the Greater Toronto Area of Southern Ontario: Ganatsekaigon Creek (City of Pickering), Wilket Creek (City of Toronto), and Morningside Creek (City of Toronto). The grain size distribution at each site was calculated using a Wolman Pebble count with a 200-stone sample size. Bedload transport was monitored over three years using Radio Frequency Identification (RFID) tracer stones, and periodic topographic surveys were conducted. A total of 300 tracers in 3 size classes were seeded in each site in August 2015. Tracer positions were recorded after each major rainfall event during the active field season each year, resulting in a total of 10, 12, and 13 recoveries in Ganatsekaigon Creek , Wilket Creek, and Morningside Creek, respectively. With each recovery, the travel distance of each tracer since its last known position is calculated. Detailed topographic surveys of the channel bed were conducted in the summers of 2016 and 2018 using a total station. Surveys were used to create DEM of Difference (DOD) at each site after a Triangular Irregular Network interpolation.