Status: Impaired

Restrictions on Fish and Wildlife Consumption was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to the presence of mercury from historic Cornwall industries.

This BUI has remained “Impaired” since 1992.

IJC Delisting Guidelines

When contaminant levels in fish and wildlife populations do not exceed current standards, objectives or guidelines, and no public health advisories are in effect for human consumption of fish or wildlife. Contaminant levels in fish and wildlife must not be due to contaminant input from the watershed.

AOC Delisting Criteria

1.1 Consumption advisories for fish of interest in the AOC are non-restrictive or no more restrictive than the advisories for suitable reference site(s) due to contaminants from locally controllable sources.

1.2 An increase in the Akwesasne community knowledge and/or willingness to engage in safe biocultural and traditional consumption of fish and wildlife.

Status: Not Impaired

Tainting of Fish and Wildlife Flavour was identified as “Requires Further Assessment” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to potential tainting from Domtar effluent, combined with a survey which found no concerns of tainting from local anglers.

This BUI was redesignated as “Not Impaired” in the 1997 Stage 2 Report: Great Lakes, Great River, as testing of Domtar effluent found no potential for tainting. 

IJC Delisting Guidelines

When survey results confirm no tainting of fish or wildlife flavor. 

AOC Delisting Criteria

2.1 When the zone of potential tainting extends less than 100 metres from the Domtar diffuser and there are no complaints about fish tainting in the AOC.

Status: Impaired

Degradation of Fish and Wildlife Populations was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to the construction of the St. Lawrence Seaway, commercial and recreational fisheries, the presence of invasive species, shoreline development, and the presence of contaminants.

This BUI has remained “Impaired” since 1992.

IJC Delisting Guidelines

When environmental conditions support healthy, self-sustaining communities of desired fish and wildlife at predetermined levels of abundance that would be expected from the amount and quality of suitable physical, chemical and biological habitat present. An effort must be made to ensure that fish and wildlife objectives for Areas of Concern are consistent with Great Lakes ecosystem objectives and Great Lakes Fishery Commission fish community goals. Further, in the absence of community structure data, this use will be considered restored when fish and wildlife bioassays confirm no significant toxicity from water column or sediment contaminants.

AOC Delisting Criteria

3.1 Maintenance of marsh bird and amphibian populations and diversity at or above Great Lakes non-Area of Concern averages as determined by the Marsh Monitoring Program of Bird Studies Canada.

3.2 Presence of successfully reproducing osprey in the Area of Concern for a minimum 5 years.

3.3 Maintain no net loss of populations of great blue herons, great egrets, black-crowned night herons, common terns, and herring and great black-backed gulls on Dickerson Island and Strachan Islands or other suitable areas within or immediately adjacent to the Area of Concern.

3.4 Temporal trends in contaminant levels in herring gulls, night herons, snapping turtles and/or cormorant eggs are stable or declining. Spatial comparisons show that contaminant concentrations in eggs of the above species in areas under the influence of the Area of Concern are equal to or less than those from sites removed from any influence of the St. Lawrence River Area of Concern.

3.5 Acceptance for implementation of actions recommended in the Lake St. Francis Fisheries Management Plan, Walleye Fisheries Management Study, Muskellunge Management Strategy and broader St. Lawrence River Restoration plans for these species to help restore, protect and monitor populations of muskellunge, sturgeon and walleye.

3.6 Establishment of fish community objectives by the Ontario Ministry of Natural Resources Lake Ontario Management Unit for Lake St. Francis. These objectives will, when established be imbedded within the Fisheries Management Plan.

Status: Requires Further Assessment

Fish Tumours or Other Deformities was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to tumours found in white suckers and walleye.

This BUI was redesignated as “Requires Further Assessment” in the 1997 Stage 2 Report: Great Lakes, Great River, as data from previous fish tumour studies was deemed not suitable for assessing the BUI against the guidelines.

This BUI has remained “Requires Further Assessment” since 1997.

IJC Delisting Guidelines

The incidence rates of fish tumors or other deformities do not exceed rates at unimpacted control sites and when survey data confirm the absence of neoplastic or preneoplastic liver tumors in bullheads or suckers.

Status: Not Impaired

Bird/Animal Deformities or Reproductive Problems was identified as “Requires Further Assessment” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to the presence of contaminants and a lack of available data.

This BUI was redesignated as “Not Impaired” in the 2007 Update to the Stage 2 Report: Great Lakes, Great River, as studies found that deformities were no more common in snapping turtles and colonial waterbirds from the AOC than those from upstream reference sites.

IJC Delisting Guidelines

When the incidence rates of deformities (e.g. cross-bill syndrome) or reproductive problems (e.g. egg shell thinning) in sentinel wildlife species do not exceed background levels in inland control populations.

Status: Not Impaired

Degradation of Benthos was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to high levels of contaminants in the environment, and the presence of contaminants in benthos.

This BUI was redesignated as “Not Impaired” in the 2007 Update to the Stage 2 Report: Great Lakes, Great River, as studies showed no contaminants in benthos and no risk of biomagnification.

IJC Delisting Guidelines

When the benthic macroinvertebrate community structure does not significantly diverge from unimpacted control sites of comparable physical and chemical characteristics. Further, in the absence of community structure data, this use will be considered restored when toxicity of sediment-associated contaminants is not significantly higher than controls.

AOC Delisting Criteria

5.1 This use impairment will be delisted when benthic community structure, diversity and abundance are comparable for sites with similar habitat (sediment grain size, water velocity) in the AOC at location upstream and downstream of Cornwall industrial and municipal discharges, and/or in comparison to suitable reference sites. Furthermore, acute and/or chronic effects on benthos attributable to trace metals or organics should not be evident at sites within the AOC.

5.2 This use impairment will be delisted when benthic invertebrate tissue contaminant concentration are comparable in the AOC at locations upstream and downstream of Cornwall industrial and municipal discharges for the contaminants of concern (contaminants that biomagnify in the aquatic food chain) or in cases where benthic invertebrate tissue contaminant concentration are greater than upstream sites but below concentrations considered to impair the beneficial uses associated with the consumption of fish and wildlife.

Status: Not Impaired

Restriction on Dredging Activities was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to contaminant levels which were higher than the guidelines for open water disposal of dredged sediment.

This BUI was redesignated as “Not Impaired” in the 2007 Update to the Stage 2 Report: Great Lakes, Great River, as there is no navigational dredging in the AOC and the Cornwall Sediment Strategy was implemented to protect contaminated sediments from being disturbed.

IJC Delisting Guidelines

When contaminants in sediments do not exceed standards, criteria, or guidelines such that there are restrictions on dredging or disposal activities.

AOC Delisting Criteria

7.1 This use impairment will be delisted when appropriate technologies have been identified that will protect against contamination of the river during dredging, transport, and disposal of sediment contaminated above the Lowest Effect Level (LEL).

Status: Impaired

Eutrophication or Undesirable Algae was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to excess nutrients, the presence of invasive species and the construction of the Moses-Saunders Power Dam.

This BUI has remained “Impaired” since 1992.

IJC Delisting Guidelines

When there are no persistent water quality problems (e.g. dissolved oxygen depletion of bottom waters, nuisance algal blooms or accumulation decreased water clarity, etc.) attributed to cultural eutrophication.

AOC Delisting Criteria

8.1 Demonstrate a reduction in phosphorus concentrations at St. Lawrence River tributaries as measured at Provincial Water Quality Monitoring Network (PWQMN) sites.

8.2 The mean annual Total Phosphorus (TP) concentration in Lake St Francis should not exceed 20 ug/L in waters between the two-meter nearshore contour and the open channel.

8.3 No evidence of sustained and widespread undesirable algae blooms in the St. Lawrence River, source-specific to the Area of Concern, whether free-floating or attached to surfaces. Site specific occurrences at tributary mouths and in developed areas should be monitored and nutrient control programs put in place.

8.4 Create and initiate a plan to improve water quality at the mouth/nearshore areas of Area of Concern tributaries to achieve site-specific annual mean TP concentrations, or in accordance with MCA standards when tributaries are on MCA lands.

Status: Not Impaired

Restrictions on Drinking Water Consumption, or Taste or Odour Problems was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to contaminants from Domtar causing taste and odour problems downstream of Cornwall.

This BUI was redesignated as “Not Impaired” in the 1997 Stage 2 Report: Great Lakes, Great River, as filters were installed at the Cornwall Water Treatment Plant in 1997.

IJC Delisting Guidelines

For treated drinking water supplies: 1) when densities of disease-causing organisms or concentrations of hazardous or toxic chemicals or radioactive substances do not exceed human health objectives, standards or guidelines; 2) when taste and odor problems are absent; and 3) when treatment needed to make raw water suitable for drinking does not exceed the standard treatment used in comparable portions of the Great Lakes which are not degraded (i.e. settling, coagulation, disinfection).

AOC Delisting Criteria

9.1This use impairment will be delisted when effective treatment is in place to remove the taste and odour problem in Cornwall drinking water.

Status: Not Impaired

Beach closings was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to beach closures caused by high levels of bacteria.

This BUI was redesignated as “Not Impaired” in 2023, as bacteria levels were below guidelines and plans such as the farm stewardship program were implemented to help control the levels of bacteria entering waterways.

IJC Delisting Guidelines

When waters, which are commonly used for total-body contact or partial body-contact recreation, do not exceed standards, objectives, or guidelines for such use.

AOC Delisting Criteria

10.1 At public beaches, no more than 20% of weekly tests (i.e., five sample E. coli geometric means) exceed the Provincial Water Quality Objective during an annual swimming season. In addition, the main/predominant sources of fecal pollution are known; most of these exceedances are associated with local events, such as significant rainfall or high wind periods.

10.2 The ‘vast majority’ of body contact water recreation areas in the Area of Concern, other than public beaches, must meet the E. coli threshold during the swimming season. Body contact water recreation sites that do not meet these objectives are highly localized and exceedances occur only sporadically (i.e. the Area of Concern does not show widespread evidence of fecal pollution).

10.3 For body contact water recreation areas where water quality objective exceedances occur, the main sources of fecal pollution must be identified, pollution control plans must be developed, and these plans must be actively implemented.

Status: Not Impaired

Degradation of Aesthetics was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to masses of aquatic weeds and odour issues.

This BUI was redesignated as “Not Impaired” in the 1997 Stage 2 Report: Great Lakes, Great River, as odours from Domtar were greatly lowered and masses of plants were found to be caused by factors outside the scope of the RAP.

IJC Delisting Guidelines

This use impairment will be delisted when the waters are devoid of any substance which produces a persistent objectional deposit, unnatural color or turbidity, or unnatural odor (e.g. oil slick, surface scum).

Status: Not Impaired

Added Costs to Agriculture or Industry was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to the impacts of contaminants on fisheries and tourism.

This BUI was redesignated as “Not Impaired” in the 1997 Stage 2 Report: Great Lakes, Great River, as the impacts to fisheries would be addressed by the Delisting Criteria for BUI 01 – Restrictions on Consumption of Fish and Wildlife, and no added costs were found for agriculture or other industries.

IJC Delisting Guidelines

This use impairment will be delisted when there are no additional costs required to treat the water prior to use for agricultural purposes (i.e. including, but not limited to, livestock watering, irrigation and crop-spraying) and industrial purposes (i.e. intended for commercial or industrial applications and noncontact food processing).

Status: Requires Further Assessment

Degradation of Phytoplankton and Zooplankton Populations was identified as “Requires Further Assessment” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to the presence of invasive species, and the lack of available data.

This BUI has remained as “Requires Further Assessment” since 1992.

IJC Delisting Guidelines

When phytoplankton and zooplankton community structure does not significantly diverge from unimpacted control sites of comparable physical and chemical characteristics. Further, in the absence of community structure data, this use will be considered restored when phytoplankton and zooplankton bioassays confirm no significant toxicity in ambient waters.

Status: Impaired

Loss of Fish and Wildlife Habitat Consumption was identified as “Impaired” in the 1992 Stage 1 Report: Environmental Conditions and Problem Definitions, due to the construction of the St. Lawrence Seaway and Moses-Saunders Power Dam, and shoreline development.

This BUI has remained “Impaired” since 1992.

IJC Delisting Guidelines

When the amount and quality of physical, chemical, and biological habitat required to meet fish and wildlife management goals have been achieved and protected.

AOC Delisting Criteria

14.1 Create and initiate a plan to protect the number, the form and function of coastal provincially significant wetlands, with a goal of “no net loss” in area.

14.2 Create and initiate a plan to establish a minimum riparian cover width of 3 meter, or greater, along the St. Lawrence River shores on Akwesasne lands, public lands and private lands.

14.3 Create and initiate a plan to improve conditions in Pattingale Creek to enhance fish and wildlife habitat.