RE: the relocation of the Wye River channel and bridge construction along highway 27
Anthropocentric changes to river/stream courses have been going on throughout history; usually by engineers, and with little knowledge about how to evaluate unintended consequences. When river channels are relocated, they should, as much as possible, match the current patterns exhibited by the undisturbed flow. If the relocation does not consider this, the consequences to the riparian zone, and floodplain, can be serious for all facets of the river system in question: erosion, deposition, bed form, sediment load (turbidity), vegetative loss, flow characteristics, ecological disruption, aquatic species, and water quality. Avoiding the potential deleterious impacts of relocating, or seriously changing a channel, requires that the proponents of change have a deep understanding of the conditions responsible for the natural water course, and how to reduce impact to those conditions. In the case of the Schedule ‘C’ Municipal Class Environmental Assessment, Public Information Centre No. 1 and 2 (bridges 027574 and 027576); highway 27, north of the city of Elmvale, ON., as related to the Environmental Assessment Act (R.S.O. 1990, c. E. 18, s. 2.), there seems to be little or no consideration of the above mentioned concerns.
Strategic project planning and implementation require knowledge of pre-project, baseline conditions as well as post-project targets so that change can be measured during and subsequent to project completion. This is the only way to measure project success and to mitigate risks that are anticipated that might disrupt project success. This is the process of “evaluation” and requires that targets exist within a set of indicators that measure the progress of the project.
The assessment submitted to the government has no quantitative information on the current parameters that might be impacted by this intervention nor a way of measuring the anticipated level of change towards the desired outcomes. That is, there is only qualitative reference to any of the potential changes. Interestingly, within the report, there are many instances where the report mentions potential unwanted changes to the environments mentioned above but each is followed by a “however” statement that assumes that the worst-case scenario will not happen, and suggests, without justification, that the condition of the river system may improve. These statements seem to promote the choices that have been made, and temper the assessment to confirm the choices.
Finally, the assessment indicates that the intervention will take place below the groundwater table and that the water table is under pressure (artesian, flowing), which may cause problems. I would ask the proponents to make public their hydrological study that has measured the depth to the water table and to the artesian aquifers they mention …. I would point out that the water table exists in a very shallow soil that has formed on a virtually impenetrable, thick clay bed and that the artesian surface lays below this bed. The “evaluation” is inconsistent with the known hydrological setting.
This groundwater is the subject of a large, complicated project to understand its quality; the channel relocation could impact the outcome of this study, which is being anticipated internationally. The Wye River feeds Tiny and Wye marches, before entering Severn Sound or Georgian Bay: the entire water course along the existing flow path and the marshes and shores may be threatened by this project.
Are the risks commensurate with the importance of this construction? Have the assumptions of “neutral” (no impact: from assessment) been properly assessed by the proponents? Could the bridge regeneration occur in place and provide reasonable stability for the highway and future of the river? Have we really evaluated the changes proposed???
Michael A. Powell, PhD – 215 Concord Rd. London, ON, N6G3H9
Disclosure: Mike Powell is a personal friend and colleague of Bill Shotyk, whose letter appeared in the News last week.