The effects of boat waves on sheltered waterways – thirty years of continuous study

The waves generated by boats and ships (termed wave wake, wake wash or simply wash) that operate within sheltered waterways or close to any shore, have received considerable attention over the past few decades. Although many various issues arise from the waves from vessel operations, such as damage to maritime structures and presenting a danger to other users of the waterways, it is erosion of surrounding shorelines that occurs most frequently and receives the most attention. Along with the interested parties, including those in vessel construction and operation through to regulation and monitoring, comes the inevitable and often overwhelming politics; the clash of public amenity, economics and environment.

The Australian Maritime College (AMC) first became involved in the field thirty years ago, with the assessment and monitoring of tourist vessels on the World Heritage listed Gordon River in Tasmania – a project that continues to this day. The AMC’s expertise expanded into high-speed commuter ferries, of which Australia was an early pioneer, and eventually to recreational craft. A summary of past and present research is presented, which includes: deep water wave packet development and propagation; shallow water wake components and their relationship to deep water wakes; the distribution and intensity of erosive components within vessel wakes and the opportunities for, and limitations on, their mitigation through vessel design and operation.