Wake Up - Impacts of Recreational Boat Wakes on Shoreline Habitat in the Rideau Canal Waterway

Growth in pleasure craft ownership and the emerging popularity of wake-enhancing boats have raised concerns that freshwater and riparian ecosystems may be under increased stress from recreational boating. Boat wakes, the series of waves generated by a moving boat, can have variety of potentially harmful effects on shoreline environments, including shoreline erosion, increased turbidity, habitat disturbance, and impacts to biological communities. The relative impact of boat wake energy is most pronounced in low-fetch environments where wind wave energy is limited, such as rivers and canals. We present preliminary results of a boat wake impact study conducted on the Rideau Canal Waterway (RCW), one of Canada’s most popular destinations for recreational boating. The study has two components: 1) a boat traffic survey to quantify the types and abundance of recreational boats in use on the RCW; and 2) experimental trials with different types of boats run at known speeds and distances from shore. In both study components, near-shore wave fields and turbidity were measured by RBRmaestro3 multi-channel logger to correlate boat wakes to sediment resuspension (a proxy indicator of erosion). Wakes were characterized by peak and significant wave heights and analyzed via continuous wavelet transforms. Sediment resuspension was inferred from turbidity data and correlated to boat wakes by time series analysis. The results will contribute to developing predictive models of shoreline impacts based on boat type, speed, and distance from shore that can be used to inform management action on the RCW and other Canadian waterways