Sediment transport and morphodynamics in an urbanized river: the effect of restoration on sediment fluxes

Margot Chapuis (1) , Vernon Bevan (1) , Bruce Macvicar (1) , André Roy (2)

1 Department of Civil and Environmental Engineering [Waterloo]
2 Faculty of Environment

Urbanized rivers are heavily impacted by human activities that modify their hydrology and morphodynamics. This study focuses on Wilket Creek, a small gravel-bed river (14.5 km² drainage area, 12 m width, 1% slope, D50 = 0.039 m) located in the suburban area of Toronto. Existing infrastructures are threatened by incision and lateral migration of the channel. In 2012, a 400 m long reach has been restored with a riffle-pool design that was assumed to be the most efficient to dissipate flow energy. This project investigates the interactions between hydrology, sediment transport and morphodynamics to assess the stability of the restoration design. We used topographic surveys and RFID tracking to assess the sediment mobility and morphodynamics changes in unrestored and restored sections. After two bankfull events, adjustments of the riffle-pool design consist primarily of local bank erosion and local exposure of the underlying glacial till.

Domaines: Ingénierie de l'environnement; Géomorphologie; Hydrologie

Margot Chapuis, Vernon Bevan, Bruce Macvicar, André Roy. Sediment transport and morphodynamics in an urbanized river: the effect of restoration on sediment fluxes. River Flow 2014 International Conference on Fluvial Hydraulics, Sep 2014, Lausanne, Switzerland. pp.2119-2126. ⟨hal-01285798⟩