The construction of the Seaway severed our physical access to the river and caused damage to our cultural connection to the waters, and the foods that sustained us for generations. The seaway also created an artificial environment and disturbed the natural balance that had formed along the banks of the St. Lawrence. The Kahnawà:ke Environment Protection Office has been studying the Recreation Bay for many years in order to understand the environment and come up with a long-term solution to the environmental challenges.
The low flows and wide area of the bay have been causing sediment carried from faster waters upstream to drop in the bay, slowly filling it up. The sediments coming from the Chateauguay River are very high in nutrients because of upstream agriculture and therefore aquatic plant growth is favoured and occurs very quickly. The challenge for KEPO is to develop a solution that will prevent the loss of the Recreation Bay and that will be sustainable over the long-term. KEPO has been working with experts to assess and design solutions that will meet this challenge.
The following studies have been carried out in and around the Recreation Bay. These studies can be viewed in their entirety at our office. Here is a summary:
2008: Shoreline Characterization Study – Groupe Hémisphères
This study was the first step in characterizing the health of the bay and the Kahnawà:ke shoreline more generally. It assessed the degree of human impact on all the shorelines in the community, including the Recreation Bay. This study confirmed the extent of sediment that had accumulated and also measured the high levels of phosphorus and biological oxygen demand in the water (these parameters confirm the presence of agricultural nutrients).
2011: Recreation Bay Assessment – Groupe Hémisphères
This study built on the work from 2008 with a specific focus on the Recreation Bay and was an attempt to determine the cause of the problem. The depth of sediment in the bay was measured in more detail and mapped. The study revealed that the area just downstream from the remnant natural island (a bottleneck) had the most sediment and this area was identified as a ‘shoal’. A preliminary model was completed that assessed the improvement to flow in the bay by the construction of a 10 m wide channel through the sediment.
2012 – 2013: Fish and Fish Habitat Study – AECOM
Whenever major work is considered, including dredging, it is very important to understand what the potential environmental impacts of the proposed work may be on the existing wildlife. To understand this, we needed to know what species were present in the bay. Fish surveys were done in numerous locations within the community including in the bay and also identified important habitat. The study concluded that the Recreation Bay was considered ‘very good’ fish habitat. Fifteen fish species were recorded in the inventory and they were generally healthy. The study did note, however, that the habitat was at risk because of the on-going sediment accumulation.
2014: Fish Characterization – Groupe Hémisphères
This study focused on the Recreation Bay and the development of a more comprehensive understanding of the species found there. We were specifically looking for Species at Risk such as the American eel and classifying the wetland habitat and plants found on either side of the bay. This work also concluded that the bay had very good fish habitat and recommended that work take place to maintain this habitat.
2015: Recreation Bay Modeling – Hydrosoft SA
With the information gained from previous studies, we now needed to understand how we should intervene in the bay to ensure that we achieve our desired goal and the work will be sustained. We developed a three-dimensional model that looked at all aspects of the flow through the bay. This included consideration of waves, wind patterns, flows from the St. Lawrence and Chateauguay rivers, sediment loads into the bay from various sources and the operation of the Seaway Canal. Equipment was installed in the bay for two months, one month in the spring and one in the fall, to obtain an accurate picture of what was occurring in the bay.
We looked at how different strategies would affect flow and sediment deposition in the bay. Three approaches proved to be the most beneficial, particularly when they were all done at the same time. These included:
- Dredging material from the shoal area;
- Harvesting aquatic plants regularly; and
- Increasing flow in the Seaway by modifying the operation of the Ste. Catherine locks.
These three options were adopted as a preferred approach and were carried forward to the detailed design stage.
2016 – 2017: Recreation Bay Detailed Design – AECOM
KEPO is currently developing the detailed design for the Recreation Bay to enhance the environment in the area and ensure the continued use for the community. In addition to the three flow enhancements mentioned above, three other areas in need of improvement have been identified. These include:
- Naturalizing the shoreline of Tekakwitha Island;
- Improving the soil on the island and creating pollinator habitat; and
- Enhancing the two wetlands that exist on either side of the bay, including Turtle Bay.
These measures, in conjunction with the dredging and maintenance of aquatic plants will restore and diversify ecosystems in the bay and create new opportunities for community enjoyment and use of the area.
We are currently seeking funding to undertake the work being finalized as part of the 2017 detailed design project. We will be hosting a public open house in May 2017 and we will be finalizing the plans based on feedback received. Proposed project plans will be posted on the website when they are available. Your feedback and ideas for the Recreation Bay are always welcome. Please contact KEPO at (450) 635-0600.