Surface current effects on ice floe accumulation
University of New Brunswick
A spur dike constructed on the Mackenzie River at Fort Providence, Northwest Territory creates a safe location for docking the ferry during its operation in the summer. However, because of the flow characteristics around it ice floes accumulate behind the spur dike even after the main channel is free of ice. Because ice accumulates in the ferry loading area, ferry service is not able to resume immediately after the ice bridge is decommissioned and the main channel becomes free of ice. While the ice floes prevent the ferry from operating, the only method of transportation across the river is by helicopter. This has proven to be expensive and inconvenient to the residents of the surrounding communities. If the length and orientation of the spur dike could be modified to reduce the ice blockage, transportation and daily living expenses for the surrounding communities would be significantly decreased. The main objectives of this study were to: 1) Construct a physical model at an appropriate scale replicating the bathymetry of the Mackenzie River and 2) Use the wide shallow flume to simulate flow with various configurations of the spur dike. Testing revealed that constructing a longer spur dike oriented downstream will deflect the ice into the main channel and prevent ice floes from accumulating in the ferry loading area during spring breakup. A 10 metre extension oriented 45 degrees downstream from the original spur dike produced the most promising result; it deflected the ice floes into the main channel so very little ice became trapped in the downstream eddy and re-circulated upstream to the ferry loading area.