Investigating Ship Induced Scour in a Confined Shipping Channel

Deep draft ships transiting through confined channels can significantly alter surrounding hydrodynamic conditions. The Burlington Shipping Channel is a confined channel on Lake Ontario which has experienced significant scour due to ship drawdown. A range of investigations including the development of an SGH model of the Burlington Channel have been undertaken to understand the processes leading to scouring near the channel walls. It is proposed the direction of ship motion is fundamental to the depth of scour observed at the entrances to the channel. The SGH model achieved a good level of hydrodynamic calibration and an assessment of modeled scour based on spatial variation in critical sediment size is consistent with observed scour patterns. The critical sediment diameter along the channel is an order of magnitude greater than the native bed material. In the mid-sections of the channel, scour potential is generally independent of direction of ship motion and consecutive ship movements in opposite directions appear to cause minimal net sediment transport. The development of design criteria curves for channel protection using the SGH model is presented.