William’s Creek is Port Perry’s most urbanized watercourse, with watershed characteristics that compromises its hydrology, water quality, and ecological function significantly. High stormwater flows in particular cause erosion upstream and sedimentation downstream, and create the kind of disturbed areas that are ideal for the establishment of invasive plants.
The Problem
Invasive plants, specifically Japanese knotweed, are prevalent along the banks of William’s Creek in Reflection Park. Streambank erosion in this reach presents an additional issue: the spread of Japanese knotweed root fragments downstream. Japanese knotweed is an invasive plant of great concern. Its roots can damage infrastructure and building foundations in areas where it has not been controlled, and once established, it is especially resilient to removal efforts. Invasive plant legislation has been introduced elsewhere – and will soon be introduced in Ontario as well - to explicitly control the spread of this plant.
This project aimed to manage the isolated Japanese knotweed population in Reflection Park with the intent of eradicating it before it spreads further downstream and results in more extensive and expensive control efforts.
The Process
A number of steps were involved in preparing the site, as well as removal of existing Japanese knotweed and stabilization of the streambank, while reducing on-site erosion and sedimentation downstream.
Ontario Invasive Plant Council: https://www.ontarioinvasiveplants.ca/