Sediment delivery to the Fraser River Delta; sediment transport mechanisms and modeling framework

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The objective of this research program is to advance our knowledge of the mechanics of sand-bedded river channels and, in particular, to develop physically-based predictive tools for how sediments move between their source and ultimate sink in the ocean. The program is designed to use the sand-bedded reach of the lower Fraser River as a natural laboratory to investigate and quantify processes. The Fraser also will serve as a prototype for more detailed observations in SFU's new Landscape Dynamics Laboratory that will ultimately lead to a physically-based predictive model for the morphodynamics of sand-bedded river channels, and the Fraser River in particular. At present, there is some understanding of how much sediment is moving into the sand-bedded reach of the Fraser River and how much is being deposited on the Fraser's delta and tidal flats, yet the mechanisms responsible for moving sediment through the 85 km river reach that passes through British Columbia's Lower Mainland is understood only conceptually. The dynamics of sediment in the river control response to flood flows and the quality of habitat in the channel, delta, and tidal flat environments. A physically-based model for sediment routing is required to make reliable predictions of how the sand-bedded channel and the delta environments will respond to various perturbations (i.e. a warmer climate, changes in water flux, changes in sediment flux associated with land use practices, and contemporary variation in sea level). There is a pressing need to make predictions of sediment transport in sand-bedded rivers that empty into the sea, such as the lower Fraser River, because they are often sites of intense urban development world-wide and the dynamics of these natural landscape processes significantly affect the socio-economic viability of this development.