Some of the goals pertaining to the Don river restoration efforts include better management and/or restoration of the river flow regime. Some of the problems that are currently afflicting the watershed include flooding, erosion of the surrounding land, and poor water quality which could ultimately negatively affects the river’s aquatic/terrestrial communities. My partner Gabriella Gerzon and I explored River Bank 1 for observation of potential ongoing problems with the bank and/or stabilization efforts that may have been put in place in the past. During our hike we noticed successful efforts such as fencing along the bank, as well as some areas that need work, such as a broken gabion and erosion.
The first photo we took of the bank (Figure 1), before we found a way to get directly to it, depicts a birds-eye view of the location from the Bayview street bridge. As seen in the picture, a fence has been installed alongside the riverbank that refrains the land from slumping into the river. It is holding up well, unlike the scattered pile of rocks that lie prior to its instalment. It seems as though these rocks were placed in this location to act as a gabion, although from this picture it is hard to see the enclosing wiring. The rocks have dispersed farther than the border of the riverbank and have slightly began to enter the stream, potentially restricting its flow. This is an area of concern that needs more attention in restoring a gabion and/or extending the fencing to help better manage the stream flow and reduce the potential of flooding.
The next thing we noticed at riverbank 1 was on the opposite side of the fencing. Figure 2 shows the erosion that was seen along the entire stretch of the river in our sight. This side of the bank, as it appeared, had no manmade fencing or structures to battle this potential problem and therefore there is a prominent cutoff of where the water eroded the soil, expanding the river width. When soil is eroded from an area, it loses its most nutrient-rich layer, and therefore soil quality is reduced. This could cause clearing of riverbank vegetation and enable more flooding (Rinaldi et al, 2007).
The last thing noted at this riverbank site was a large pipe expelling water into the river (Figure 3). The Don River is known to serve as a stormwater conduit which carries snowmelt and rain water. It inevitably contains runoff and sewage flow which eventually get carried into the lake (Hayashi et al, 2002). This could also have a negative impact on the vegetation and aquatic communities surrounding the bank.
After visiting Glendon’s riverbank it is reasonable to conclude that more effort needs to be put in to the restoration and preservation of the riverbank as its degradation could have detrimental effects on its surrounding vegetation as well as ecosystem as a whole, extending to the tributaries of the river.
Hayashi, M., & Rosenberry, D. O. (2002). Effects of ground water exchange on the hydrology and ecology of surface water. Ground water, 40(3), 309-316.
Rinaldi, M., & Darby, S. E. (2007). 9 Modelling river-bank-erosion processes and mass failure mechanisms: progress towards fully coupled simulations. Developments in Earth Surface Processes, 11, 213-239.