Beneficial Use Impairments, or BUIs, are changes in chemical, physical and/or or biological properties that have impaired ecosystem benefits, or uses. A status summary for the Thunder Bay Area of Concern follows:
Delisting Criteria and Additional Information
The following information sets out the criteria for removing, or “delisting” the remaining impairments in the Thunder Bay Area of Concern.
FISH HEALTH CRITERIA
DYNAMICS OF FISH POPULATIONS
Fish populations will no longer be impaired when the fish community within the AOC has the following characteristics, as observed by the MNR Fish Community Index Netting (FCIN) program.
- The fish community within the Thunder Bay AOC should be similar to nearshore (0–80 m deep) fish communities adjacent to the AOC for a minimum of three consecutive years, as measured by the relative abundance (Catch Per Unit Effort) and species composition of the fish community.
- Also, the nearshore fish community should be dominated by self-sustaining populations of native species showing the following characteristics:
• The mean age of lake trout is greater than eight years.
• The length at age of seven-year old lake trout caught in the FCIN or harvested by the commercial fishery is stable and greater than 430 mm.
* The FCIN and/or commercial catch is dominated by mature fish and many age classes.
• Population capable of supporting a commercial fishery with sustainable yields that do not exceed 0.51 kg/ha/yr (Busiahn 1990).
• Maximum total annual mortality does not exceed 60-65%
• Average age in the catch should be two years older than the age at which 50% of the population matures.
LAKE STURGEON, WALLEYE, AND BROOK TROUT
The overall understanding of the population dynamics of these native species within Thunder Bay is limited, therefore it is difficult to establish population criteria. Efforts are currently underway to better understand these species and their habitat use within Thunder Bay and its tributaries. As a result, criteria that reflect lake sturgeon, walleye, and brook trout populations are covered under the loss of habitat delisting criteria.
Lead Agency: Ontario Ministry of Natural Resources and Forestry.
LOSS OF FISH HABITAT
This beneficial use will no longer be impaired when the following habitat-related projects from the Thunder Bay Stage 2 RAP Report (2004) have been completed, evaluated for effectiveness, and areas support diverse self-sustaining biological communities:
- Alleviation of water quality barriers to fish migration in the Kaministiquia River
- Re-vegetation projects in McVicar Creek and McKellar River
- Habitat improvements associated with the creation of Sanctuary Island at the mouth of McVicar Creek
- Habitat remediation on McKellar River
- Rehabilitation of walleye spawning habitat at Current River Estuary
- Improving salmonid access to the upper reaches of the Current River
- Implement the Slate River Watershed Management Plan
- Monitoring to support lake sturgeon rehabilitation strategy
- Implement plan for shoreline naturalization within the Thunder Bay AOC
In addition to the Stage 2 RAP projects, the following should also be completed:
- Remaining and created wetlands are protected from further degradation through existing environmental legislation, with provincial standards used to inventory and classify wetlands within the Thunder Bay AOC
- Provide unrestricted access to critical spawning habitat by providing adequate flow in the Kaministiquia River
- Ensuring that native fish populations are not negatively affected by industrial water-use practices, including water intake and discharge
Lead Agency: Ontario Ministry of Natural Resources and Forestry
FISH CONSUMPTION RESTRICTIONS
This beneficial use will no longer be impaired when the fish consumption advisories in the AOC (inner and outer Harbour) are no more restrictive than the advisories for the same contaminants in an open water reference site (Schreiber Point to Sewell Point – Block 7), based on samples collected in the same time frame (<5 years) for a minimum of two consecutive studies
Lead Agency: Ontario Ministry of the Environment and Climate Change
Status: Requires further assessment
FISH TUMOURS AND OTHER DEFORMITIES
This BUI will no longer be impaired when a survey of 100 white suckers (Catostomus commersoni) – and more if available – encompassing a diverse age range indicates a liver tumour prevalence rate of less than 5%.
WILDLIFE HEALTH CRITERIA
DYNAMICS OF WILDLIFE POPULATIONS
DELISTING CRITERIA (proposed)
Monitoring data shows that the wildlife community (at a population level) does not differ significantly from the abundance that would be expected from the amount and quality of physical, chemical and biological habitat typical of the AOC.
That the wildlife community (at a population level) does not differ significantly from suitable Lake Superior reference sites.
(Adopted from the International Joint Commission)
LOSS OF WILDLIFE HABITAT
DELISTING CRITERIA (proposed)
This beneficial use will no longer be impaired when riparian, wetland, and coastal habitat within the Thunder Bay AOC is in compliance with the guidelines set out through Environment Canada’s How Much Habitat is Enough? (2004).
In addition, remaining and created wetlands must be protected from further degradation through existing environmental legislation. Provincial standards should be used to inventory and classify wetlands within the Thunder Bay AOC.
BIRD AND ANIMAL DEFORMITIES OR REPRODUCTIVE PROBLEMS
DELISTING CRITERIA (proposed)
This beneficial use will no longer be impaired when concentrations of contaminants in wildlife tissues are below locally derived targets associated with adverse impacts of wildlife populations.
This BUI will be considered restored when contaminant levels in wildlife populations do not exceed current standards, objectives or guidelines for the protection of human health.
This beneficial use will no longer be impaired when tissue concentrations in sentinel wildlife species are comparable to suitable reference sites.
(Suggested criteria from the International Joint Commission)
SEDIMENT QUALITY CRITERIA
DEGRADATION OF BENTHOS
Benthic community impairments were originally identified in three locations within the Thunder Bay Area of Concern: the Kaministiquia River, the area adjacent to the Northern Wood Preservers (NWP) property, and the area adjacent to the former Cascades Fine Paper property (“North Harbour”). Each of the identified sites has its own unique characteristics, contaminants of concern, and prescribed management action, and therefore requires distinct delisting criteria.
Lower Kaministiquia River (including Mission & McKeller Rivers):
This BUI will no longer be impaired when monitoring data indicates that benthic invertebrate communities and contaminant concentrations in sediment from the lower Kaministiquia River, Mission River, and the McKellar River remain stable (similar to 2005 data), or are improving.
Northern Wood Preservers Site:
The Northern Wood Preservers Alternative Remediation Project for contaminated sediment (NOWPARC) was completed in 2003. Benthos will no longer be impaired when monitoring data indicates that the benthic community from the NOWPARC area is similar to the benthic community in other parts of the harbour.
North Harbour Industrial Site:
This BUI will no longer be impaired when:
1) monitoring data indicates that contaminant concentrations in sediment and/or benthos from the North Harbour are showing a declining trend in concentrations and benthic communities are improving; and
2) site specific criteria have been met (or objectives accomplished) as per the sediment management plan (to be added when available).
RESTRICTIONS ON NAVIGATIONAL DREDGING
No additional management action is necessary to restore restrictions on dredging as a beneficial use impairment within the Thunder Bay AOC.
(Update 2009-2012, p. 17)
Status: Not Impaired.
WATER QUALITY IMPAIRMENTS
This beneficial use will no longer be impaired when:
All public beaches have identified primary sources of fecal pollution and pollution control plans have been developed and implemented, including:
- management of stormwater inputs;
- upgrades of septic systems to provincial standards;
- implementation of a management program for birds and animals;
- completion of feasible actions to improve water circulation;
- water quality testing carried out at all public beaches on a regular, frequent and ongoing basis demonstrates that 80% of geographic means have E. coli counts of 100 or less colony forming units per 100ml of water (Provincial Water Quality Objectives) based on a five year monitoring average.
DEGRADATION OF AESTHETICS
This beneficial use will no longer be impaired when the waters are devoid of any substance which produces a persistent objectionable deposit, unnatural colour or turbidity, or unnatural odour (e.g. oil slick, surface scum).
DEGRADATION OF PHYTOPLANKTON AND ZOOPLANKTON POPULATIONS
None written. There is a recommendation in the Update 2009-2012 (p. 19) that the BUI be classified as NOT impaired.
Status: Requires further assessment.
ADDED COSTS TO AGRICULTURE OR INDUSTRY
Status: Redesignated to Not Impaired in 2004 (Stage 2 report, page 18).