A history of industrial activity in the area surrounding Kingston Inner Harbour (KIH) resulted in contamination of the sediment that lines the harbour bed. Historical uses included a railway, shipyard, fueling, coal gasification, tannery, lead smelter, landfill and other operations.
Studies have concluded that people, fish and wildlife may experience negative health effects (risks) if exposed to this contaminated sediment. Despite several decades of time for natural recovery, several areas have not recovered enough to be safe for current uses by people (such as wading), and fish and wildlife for feeding. Therefore, management measures have been recommended to address those risks.
The work is being led by Transport Canada and Parks Canada as much of the sediment of interest falls in parts of the harbour, called water lots, which are owned and managed by the federal government. The proposed management area is bound by Highway 2 (LaSalle Causeway Bridge) to the south and Belle Island/Cataraqui Park to the north, on the western side of the harbour.
A percentage of the proposed management area is under the administration of the City of Kingston. Transport Canada and Parks Canada are exploring opportunities to partner with the City.
The conceptual sediment management plan includes areas of dredging (removal), capping (covering with clean material), shoreline modifications (which entail careful and ecologically-minded solutions), and areas that will be left to recover naturally. The goal is to balance the protection of sensitive species, habitats, and valued features with a reduction of risks associated with contamination.
Prior to project implementation, an impact assessment will be completed, and feedback will be requested from Indigenous communities, local stakeholders and members of the public. The impact assessment will determine if any aspect of the project could cause significant adverse environmental effects and will identify measures required to mitigate those effects.
A complex history of industrial activity in areas surrounding Kingston Inner Harbour resulted in contamination of sediments (material lining the lake bottom) in Transport Canada, Parks Canada, and City of Kingston water lots. The chemicals of concern include metals, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The chemicals are mostly from historical land uses, including a former rail yard, landfill, coal gasification plant, tannery, lead smelter, shipyards, fuel and oil docks, scrap/demolition yards, and other industrial activities. Scientific studies have concluded that the contamination in the Kingston Inner Harbour may pose risk to humans, fish, birds, mammals, and other aquatic life. Despite several decades of being left to recover, several areas have not recovered enough to be safe, and continued recovery will be very slow if no sediment management action is taken.
Sediment investigations and risk assessments were completed following standard federal and provincial guidance, which kept the methods consistent with other assessments across Canada. The guidance included the Canada-Ontario Decision-Making Framework for Assessment of Great Lakes Contaminated Sediment (ttps://publications.gc.ca/collections/collection_2010/ec/En164-14-2007-eng.pdf) and the Framework for Addressing and Managing Aquatic Contaminated Sites under the Federal Contaminated Sites Action Plan (https://www.dfo-mpo.gc.ca/pnw-ppe/fcsap-pascf/docs/1-eng.htm). Federal Expert Support Departments (including Public Services and Procurement Canada, Health Canada, Fisheries and Oceans Canada, and Environment and Climate Change Canada) reviewed the investigations and provided technical support to Parks Canada and Transport Canada during these studies. Where warranted, adjustments were made to the technical reports to respond to the technical input of the Federal Expert Support Departments, prior to making recommendations for clean-up or management. Independent investigations were also undertaken by the Environmental Sciences Group of the Royal Military College over the last decade and a half, including scientific studies and interpretation. The results and recommendations of their studies were also reviewed in a similar way and were broadly consistent with those completed by the federal waterlot owners, providing additional confidence that the outcomes of the investigation are scientifically sound.
The strategy was designed to balance the least amount of environmental disturbance with the greatest degree of contaminant risk removed. With this in mind, the conceptual sediment management plan includes leaving sediments alone for most of the harbour, because the risks in most areas are low. Physical management (including areas of dredging, capping or shoreline engineering) was selected only in areas where risks are greatest to people, fish, or wildlife. Although sometimes nature can heal itself by either breaking down contaminants or slowing burying them with cleaner deposits, these processes may not be fully effective and can take a very long time. In Kingston Inner Harbour, the burial of contaminated sediment is very slow, as sediments are frequently stirred up by waves, ice, fish, and human activities.
Yes, the strategy follows scientific investigation methods, combined with a standardized approach used for contaminated federal sediments across Canada. The process for the sediment management plan was based on guidance developed by both the Canadian and Provincial governments (Canada-Ontario Decision-Making Framework for Assessment of Great Lakes Contaminated Sediment and Framework for Addressing and Managing Aquatic Contaminated Sites under the Federal Contaminated Sites Action Plan). This guidance provides a science-based ecosystem approach to sediment assessment and considers potential effects on sediment-dwelling and aquatic organisms, as well as potential for contamination to accumulate in the food chain. The Framework used was intended to standardize the decision-making process while also being flexible enough to account for site-specific considerations. In addition to providing a tiered scientific process of investigation, the Framework includes some guiding principles that have been applied to the strategy, which include: (1) that it shall be applied within the context of common sense (not applied inflexibly); (2) that potential sources of ongoing contamination are addressed before undertaking clean-up; and (3) that the impacts of the plan do not cause more environmental harm than good.
No, the plan is currently at the concept stage, and will be refined based on feedback from Indigenous communities, local stakeholders, and the public, as well as results from further biological, chemical and archeological studies of the harbour.
The conceptual sediment management plan proposes to leave sediments alone for most of the inner harbour, because the risks to people, fish, and wildlife in most areas are low. Removal of the sediment was selected only in those areas where the risks were scientifically determined to be above safe levels to people, fish, and/or wildlife. The conceptual sediment management plan also balances the desire to limit the amount of environmental disturbance, and limit the costs and disruptions associated with the clean-up, while accomplishing a meaningful level of chemical risk reduction. Some sediment needs to be removed (i.e., dredged) because it contains high concentrations of contaminants that can be harmful to living organisms. These contaminants can persist in the environment for a long time and treating sediment in place is very difficult. Fish may eat items that have been exposed to the sediment contamination, and birds or people could then eat the fish. Also, the contaminants might touch the skin of people that wade or swim in the harbour, or people could swallow the sediment by accident. By carefully removing areas of sediment with high concentrations of contaminants, while using environmental controls to prevent spreading of these contaminants throughout the harbour, we can reduce the amount of contamination in the harbour and the risks to people, wildlife, fish, and their food.
Although sometimes nature can heal itself by either breaking down contaminants or slowly burying them with cleaner deposits, these processes may not be fully effective and/or can take a very long time in areas where contaminant inputs have overwhelmed nature’s capacity to heal. In Kingston Inner Harbour (KIH), the answer depends on the section of the harbour, as the contamination differs among areas of the harbour with respect to both overall magnitude of contamination and combinations of chemicals present. In a significant portion of the harbour, the level of contamination is low enough that the slow ongoing processes of degradation and burial are sufficient. However, in other areas the degree of contamination has exceeded nature’s capacity to recover naturally; the continued presence of moderate to high levels of some chemicals, despite the legacy source being discontinued, shows that natural river processes on their own, although important, have not yielded a reduced acceptable risk over a reasonable time frame. In KIH, the burial of contaminated sediment is very slow, as sediments are frequently stirred up by waves, ice, fish, and human activities. These areas are also an ongoing source of contamination to the cleaner areas because the sediments are redistributed throughout the harbour, as documented by the sediment transport investigations.
The objective of the sediment management project is to provide a level of protection that is sufficient for many users of the harbour, including humans and animals. Although some can make use of the harbour now in the way they would prefer or require, some cannot. In some areas of the harbour, there are visible impairments (e.g., fish deformities, aquatic community disturbance), some risks that are not easily visible (e.g., long-term human health effects), and the range of uses for recreation (e.g., wading, swimming, and fishing) is limited.
It is neither possible nor necessary to remove 100% of the contaminants. Low levels of chemical are safe and common in active harbours and urban environments. The goal is to remove the sediments with the highest amounts of chemicals to reduce the risks to an acceptable level. The level deemed safe is based on science and the protection goals for the harbour. Reaching safe levels will be monitored during and after the project to verify that the methods chosen work as intended.
Remediation typically involves removing contaminants from a site through on-site treatment or off-site disposal. Risk management typically involves managing contaminants in place, using covers and/or measures to block the exposure pathways identified as causing a potential risk. Often, risk management does not require any physical changes to the environment, but rather monitoring the conditions of recovery over time. Both remediation and risk management strategies are designed to reduce risks, and both strategies can be protective of human and ecological health. Various factors (e.g., engineering feasibility, financial responsibility, legal considerations) must be considered when choosing which remediation and/or risk management option(s) to use. Remediation and risk management measures can be used either alone or in combination to successfully manage risks in an environmentally and financially responsible manner.
Some of the highest concentrations of PAHs and PCBs in the harbour are in shoreline areas that are easily accessible to people. Shoreline works are being proposed to reduce the levels of these nearshore contaminants and prevent accidental contact with the sediment. The benefit of these removals is greater than for central harbour areas that are contacted less frequently by humans. The project team will be looking for opportunities for habitat conservation gains that will improve existing habitat and address present ecological impairments. Shoreline plantings and other natural options for shoreline areas will be considered as part of detailed design.
There will be no additional restrictions to humans or wildlife after the project is complete; however, the consumption advisory for fish will remain as the contamination from Kingston Inner Harbour alone is not the primary driver for the fish consumption advisory.
Project timelines will be confirmed during the design process. Currently, we are undertaking Indigenous and public consultation on the conceptual sediment management plan. It is estimated that detailed design for the project and environmental impact assessment will begin in 2023, and physical works could begin in 2025; however, this is subject to change as planning progresses. Physical works are anticipated to take 2–3 years to complete. Once the physical works are complete, long-term monitoring of the site will take place. Click here to visit the “Project Schedule” section for more details.
The intent of the sediment management project is not to combat erosion, but rather to reduce the potential for exposure to nearshore contaminants, while also preventing shoreline work from negatively impacting wildlife habitat capacity (e.g., turtle access to laying areas). The project team will be looking for opportunities for habitat conservation gains that will improve existing habitat and address present ecological impairments. Riparian plantings and natural options for shoreline areas will be considered as part of detailed design.
Various “softer” shoreline management options can and will be considered to ensure the shoreline incorporates riparian habitat, is functional for wildlife (i.e., maintains turtle access to laying areas), and reduces the potential for exposure to nearshore contaminants. Specific design of shoreline features will be completed during the detailed design phase and will include consideration of feedback received during Indigenous and stakeholder engagement, as well as engineering factors, hydrological processes, and beneficial habitat features. It is understood that the City of Kingston has shoreline improvements planned for the area, and those improvements could be coordinated with the sediment management project. The sediment management plan is in the conceptual phase, and as such, there is flexibility in design options for shoreline features. Options will be refined through to detailed design, based on feedback from Indigenous and stakeholder engagement activities, and results of ongoing studies, including development of the DIA. The ongoing inventory of ecological resources and habitat mapping will be particularly important in refining shoreline plans. Where specific areas of sensitivity are identified, they will be accounted for in the design.
The answer depends on the area of the harbour and the nature of the sediment under the proposed dredged layers, but yes, placement of clean sediment is among the options being considered for several portions of the harbour. The clean sediment would not be a thick layer, but could be thin layers of either clean sand, siltier natural material (with more organic carbon), or a special layer of material (with activated carbon) designed to reduce chemical uptake and with desirable properties for invertebrate recolonization. The sediment management program will also include a post-management monitoring component, whereby sediment contamination and the recolonization by aquatic plants and invertebrates of natural habitats will be monitored to confirm the project objectives have been achieved. Should recolonization of dredge habitat not perform as expect, additional mitigation measures may be implemented to fast track this restoration. The details of the potential cover design will be outlined in the detailed design phase.
Archaeological assessments, including desktop evaluations, geophysical surveys, and visual inspections, are underway to ensure areas and objects of archeological significance (including shipwrecks) are appropriately identified as part of project planning. Geophysical surveys will capture high resolution imagery and mapping of features located on the bottom of the harbour, and may identify submerged features buried under the sediment. A Remotely Operated Vehicle (ROV) will be utilized to collect visual data during investigations. This information will be used to assess the context and possible cultural significance of features and to help guide the development of mitigation measures that will ensure impacts to these objects of archeological significance can be avoided. Techniques and instruments being used include multi-beam echo sounding (MBES), side-scan sonar, marine magnetometer and sub-bottom profiler.
Have more questions? Please visit the Q&A page for the project for the full list of questions and answers.