Water Stewardship Information Sources

Citation Attard, M.A., J.G. Venditti, M. Church. 2014. Suspended Sediment Transport in Fraser River at Mission, British Columbia: new observations and comparison to historical records, Canadian Journal of Water Resources. doi: 10.1080/07011784.2014.942105
Organization SFU
URL http://www.sfu.ca/~jvenditt/publications/2014_Attard_et_al_CWRJ.pdf
Abstract/Description or Keywords The sediment budget of the lower Fraser River provides the basis to understand the net sedimentary changes in the river
and delta distributary channels and sediment delivery to the Strait of Georgia. Currently, it is not possible to construct
the contemporary sediment budget because the input and output volumes of sediment to the sand-bedded reach of the
river are unknown. In this study, the results of a sediment sampling program at Mission, British Columbia, designed to
explore sediment delivery into the sand-bedded reach and delta over an annual hydrograph, are presented. The 2010
daily sediment load, in a year with a low freshet, varied between 2700 tonnes in April and 100,732 tonnes in late June.
The annual sediment load was ~7.2 M t. About 70% of the 2010 sediment load transport was silt- and clay-sized material.
Most of the sand transport occurred during the high-flow months of May, June and July. The threshold discharge
for significant sand suspension lies between 5000 and 5700 m3
/s. In 2010, 94% of the total load and 97% of the sand
load were moved when the river discharge was above 1000 m3
/s. A strong hysteresis for silt-clay, but a weaker effect
for sand, was found. This pattern of transport is consistent with observations between 1966 and 1986 by the Water Survey
of Canada. The 2010 sediment budget is on the low side of historically measured annual suspended sediment loads,
raising the possibility that recently there may have been a secular shift in the suspended sediment influx into the estuary.
Information Type article
Regional Watershed Lower Fraser
Sub-watershed if known Fraser River
Aquifer #
Comments
Project status
Contact Name Jeremy Venditti
Contact Email [email protected]