A straightened concrete channel was replaced with natural meanders and habitat features such as riffles, pools and runs, improving fish habitat and invertebrate habitat.
Toronto and Region Conservation Authority’s Alfred Kuehne Boulevard Stream Realignment Project is located in the City of Brampton, within the highly urbanized Etobicoke Creek watershed. This restoration site is approximately 400 metres long.
Approximately 60 per cent of Etobicoke Creek has no natural cover or has been altered through straightening. Because of this, increased flow in the water channel is recognized as one of the main reasons for the creek’s degraded aquatic habitat. Adding to the negative impacts is stormwater run-off from the neighbouring industrial parks. Pollutants from the road and parking lots run-off unfiltered into the creek, contributing to the decrease in water quality.
Within a natural stream channel, flora and fauna communities can adapt to survive a periodic disturbance provided that a natural balance returns to the system. But anthropogenic alterations of a stream course (such as channelization) do not typically mimic natural functions. This can cause frequent disturbances that communities cannot adapt to.
The Alfred Kuehne Boulevard Stream Realignment Project incorporates a natural channel design, adding meanders and riffle pool sequences to the creek to reduce the energy of the water flow and return the stream to a more desirable frequency of disturbance. The design also improves fish and invertebrate habitat, enhancing the integrity of the trophic structure.
TRCA increased vegetation through tree and shrub plantings, providing greater cover for bird, mammal and amphibian species within the area. The creation of offline ponds or wetlands further enhances the site and provides a measure of flood control during frequent storm events. This project limits urban run-off, which decreases the flow of the creek and limits the level of pollutants reaching the creek.
For more information on any of TRCA’s restoration projects, please visit https://trca.ca/conservation/restoration/