Sediment movement in lakes in the central area of the Mackenzie Delta, N.W.T.
Ferguson, Mary Elizabeth
This study is concerned with the movement of water and sediment into and out of three characteristic lake systems in the Mackenzie Delta. The literature reveals that there have been few attempts to quantify sediment movement and to establish rates of evolution of any of the lakes found in the Mackenzie Delta. The major research objectives were: 1) to determine a sediment budget for each of the three lake/channel systems; 2) to determine sedimentation rates in the lakes with particular attention focused on the lake deltas. Field work was undertaken to measure the sediment budget within the study lakes. Established sampling methodologies used by Water Survey of Canada and a number of relatively new sampling devices were employed. Data indicate that there is a positive influx of sediment to all three lakes from breakup in early June to the end of August. In all three lakes the greatest depths of sediment deposited were near the channel entrances on the lake deltas. There were differences in rates of sedimentation between lakes which can be explained by the types of channels which connect the lakes to the main distributary. South Lake, which is connected to the main distributary, had a larger sedimentation rate than Skidoo Lake which is connected by a longer channel. The lowest sedimentation rate occurred in NRC Lake, a small perched, lake which is not connected directly to the main distributary.