River and Suspended Sediment Discharge into Byam Channel, Queen Elizabeth Islands, Northwest Territories, Canada

Résumé

During 1974, a stream from a small drainage basin (117 km²) on the east coast of Melville Island discharged approximately 1.63 × 10,000,000 cubic m water containing 7.08 × 10,000,000 kg suspended sediment. Because nearby basins show hydrological similarity, these data can be extrapolated to provide an indication of the total suspended sediment discharge into the adjacent channels. The results suggest that much of this sediment is not deposited in the channels; rather it is incorporated into the active delta fronts or possibly transported out of Byam Channel above a pycnocline. The values agree well with a hydrological study on nearby Bathurst Island where predicted discharge values for both runoff and suspended sediment are within an order of magnitude of those measured. Recent attention has focussed on the Mecham River which flows into Bridport Inlet, the site of a proposed LNG terminal which is to be situated on an active delta front. Values extrapolated from this study indicate that design criteria must consider typical runoffs of 1.2 × 100,000,000 m³ with peak mean daily discharges in excess of 9.0 × 1,000,000 m³/day and suspended sediment loads of 5.0 × 100,000,000 kg/year.