Dredging and underwater cultural resources

Creating the navigable waters of the Trent-Severn Waterway involved engineering changes to natural watercourses, including pre-European contact water levels and flooding surrounding lands. These flooded lands, and original lake and riverbeds have archaeological potential due to their proximity to important transportation corridors that ran along rivers and lakes. Additionally, these flooded lands may have potential for early European settlement sites, which may include buildings constructed prior to flooding, or docks, cribs and other in-water structures.

All sites proposed for dredging have archaeological potential, except those that have already undergone significant disturbance, such as previous dredging or excavation.

The Policies for In-water and Shoreline Works and Related Activities clearly state that dredging will not be permitted if cultural resources will be destroyed. As part of the review to determine if the proposed activity can be approved, the application may require an underwater Archaeological Impact Assessment (AIA).

Dredge permit application review

1. Pre-screening of new dredge permit applications by Parks Canada
• To start the dredge permit application process, applicants must fill out and submit the in-water and shoreline works permit application
• All applications are subject to a pre-screening based on their location, and known cultural resource finds and recorded archaeological sites.
• All applications are subject to a fee and will be collected once the application has been submitted.
• Parks Canada provides proponents with a preliminary risk-assessment for likelihood of encountering cultural resources, which will determine if an archaeological investigation is required.
2. Notification of pre-screening results
• Applicant notified of pre-screening results, preliminary risk-assessment, and decision whether the application requires an Archaeological Impact Assessment (AIA) to proceed in the permitting process.
1. Required, if the area of impact is adjacent to a known archaeological site, and/or is over 12 m² and not previously disturbed or previously archaeologically assessed.
   Proceed to Step 3
2. Not required, if the area of impact is less than 12 m², previously disturbed, or previously undergone an archaeological assessment that identified no concerns.
   Proceed to Step 4
3. Submission of an Archaeological Impact Assessment (AIA), if required.
• Applicant proceeds with an independent underwater AIA to support their permit application.
• Procurement and cost of the AIA is the responsibility of the applicant. The AIA must be conducted under a Parks Canada Research and Collections permit by a qualified underwater archaeologist.
4. Package review
• Parks Canada reviews the dredge permit application package.
5. Issuance of decision
• Parks Canada issues dredge permit or notification that the project does not meet the necessary criteria and cannot proceed.

What are the requirements of an underwater Archaeological Impact Assessment (AIA)?

An AIA involves identifying and fully evaluating archaeological resources and the potential risks or impacts to these resources by the proposed works or activities. It includes both a desktop archaeological potential study and an archaeological fieldwork inventory. The AIA will identify if resources are present and which of those resources have significant heritage value, and/or are under the greatest threats, and will provide recommendations to eliminate or minimize potential adverse impacts of the development project on these important resources. Where appropriate, it is good practice to inform and/or consult on the proposed archaeological work and project with interested parties, including local or cultural communities connected to the potential archaeological resources. In some areas, consultation with Indigenous groups or presence of Indigenous monitors during fieldwork may be required. Recommendations on Indigenous engagement are provided with the pre-screening decision.

The AIA should include the area directly affected by the dredging activities as well as the adjacent area that may be affected by turbidity and sediment displacement caused by the activity.

An underwater AIA must be completed by a qualified underwater archaeologist under a Parks Canada Research and Collections Permit, which follows Parks Canada standards and practices. A qualified underwater archaeologist (consultant) should have a master’s degree in underwater archaeology, or a master’s degree in archaeology with significant experience conducting underwater archaeological assessments. Additionally, the consultant should have knowledge and experience in the identification of historical and Indigenous sites and artifacts common to the area.

The consultant undertaking the AIA must obtain a Parks Canada Research and Collection Permit prior to undertaking the work. The consultant should also contact Parks Canada’s Underwater Archaeology Team to obtain existing archaeological data for the site and surrounding area and to discuss proposed methodology. The methodology selected for the assessment will be based on the conditions of the proposed area, but must include one or more of the following to effectively cover the entire area of the proposed project, plus an adequate buffer zone;

• Diving survey of the proposed project area including hand fanning, probing, visual inspection, and dredging, depending upon the conditions. Note that any diving activities must follow all applicable regulations, including the Ontario Occupational Health and Safety Act;
• Snorkel surveys, in areas of very shallow water, may include the above listed methods;
• In-water sediment testing via shovel or auger. Sediment to be screened through a 6 mm mesh;
• Remote sensing surveys such as side-scan sonar sub-bottom profiling, or multibeam echosounder and remotely operated vehicles (ROV) (note that this method may not be effective for the identification of pre-European archaeological sites)

This assessment must identify potential cultural resources (or targets) to be evaluated as low, medium, and high archaeological potential. High and medium potential targets must be inspected using a diver or an ROV to determine their heritage significance. All significant cultural resources must be documented to allow for a sound impact assessment.

All the information gathered will be assessed and evaluated to produce an impact assessment report that clearly identifies the potential effects of the project activities and estimates their severity and probability of occurrence relative to the significance of the resource. The report should also provide recommendations for suitable ways to mitigate the negative impacts and indicate whether a follow-up program may be necessary.

The report should contain, but is not limited to the following sections:

1. Project outline – the objectives of the AIA with an outline of the proposed project including a description of the study area, and associated maps.
2. Historic background – History of the area of impact and its surroundings including research on the subject property, local waterbodies, and known pre-European history of the region.
3. Archaeological background – An outline of the known archaeological and previous archaeological assessments conducted in the area (the area being approximately 1 km to 3 km surrounding the study area).
4. Methodology – An outline of the methods used to assess the study area for archaeological resources. This will include the details of all equipment used in the survey, areas of coverage, and photographs of the survey.
5. Results – The results of the AIA to include details of targets, artifacts or features discovered in the study area, details on the environment of the study area, photographs of finds, maps indicating the locations of any finds, and scaled plans of any archaeological features discovered during the survey.
6. Analysis and conclusions – This section will discuss, in detail, the archaeological findings and history of the study area and provide information on the heritage value and archaeological significance of any finds, with cultural affiliations, etc., when applicable. It will also outline the potential impacts of the proposed work on the archaeological resources.
7. Recommendations – The recommendations contained in the AIA will differ, between sites, projects and resources, depending on the significance of the archaeological resources and the magnitude of the impacts. Recommended mitigation measures will be outlined and may include alterations to the original proposed plan, recommendations for additional archaeological work including complete excavation or archaeological monitoring or alternatively no further archaeological recommendations, if no resources have been found.

The report will be submitted to Parks Canada for review.

For more information please contact:

Parks Canada – Ontario Waterways
2155 Ashburnham Drive
PO Box 567
Peterborough ON K9J 6Z6
Tel: 705-750-4900
Toll Free: 1-888-773-8888
Email: on-tsw-vnts.permits-permis@pc.gc.ca

Frequently asked questions

• Do I need a permit to dredge?

  Yes. All dredging activities on the Trent–Severn Waterway require a permit from Parks Canada. This includes the removal, relocation, or dislodging of substrate, sediment, logs, stumps, or rocks from the waterbodies of the Trent-Severn Waterway.
• Why does Parks Canada regulate dredging?

  Dredging can cause significant environmental and cultural impacts. It may destroy fish habitat, disturb or destroy archaeological sites, and increase sedimentation and turbidity. Regulation ensures these activities do not harm the environment, navigation, or cultural resources protected within this national historic site.
• What is considered dredging?

  Dredging means removing or disturbing material from the bed of a lake, river, or channel. This includes:

  • Deepening a boat slip or access channel;
  • Removing or relocating logs, stumps, or rocks;
  • Maintaining previously dredged areas;
• Is dredging allowed anywhere on the Waterway?

  No. Dredging is generally discouraged and only permitted in limited cases where there are no significant environmental or cultural impacts. Dredging is not allowed in wetlands, species at risk habitat, significant fish spawning sites, areas of rock rubble, or where cultural resources would be destroyed.
• How do I apply for a dredging permit?

  Applications must be submitted through the Online In-water and Shoreline Works Permit Application available on Parks Canada’s website. Each application is reviewed under the Policies for In-water and Shoreline Works and Related Activities.
• What happens after I apply for my dredging permit?

  Permit application fees will be collected, followed by a pre-screening process to determine if the proposed site has archaeological potential.
• How long does the review take?

  Timelines vary depending on the complexity of the project and whether an AIA or environmental assessment is required. Applicants are encouraged to apply well in advance of their planned work.
• Does this dredging permit review process apply only to residential properties?

  No. The review process applies to all dredging projects, including residential, commercial, municipal, and governmental.
• Why is archaeology a concern when dredging?

  Many sites along the Trent–Severn Waterway have high archaeological potential due to centuries of Indigenous use and early European settlement. If not properly managed, dredging can disturb or destroy these underwater cultural resources.
• What is an Archaeological Impact Assessment (AIA)?

  An AIA is an archaeological study conducted by a qualified underwater archaeologist to identify and evaluate any archaeological resources that may be affected by the proposed dredging. It includes both background research and underwater field investigations.
• When is an AIA required?

  An AIA may be required if:

  • The dredging site is adjacent to a known archaeological site;
  • The proposed dredge area is larger than 12 m²; or
  • The area has not been previously disturbed or archaeologically assessed.

  If the area is small, previously disturbed, or already assessed with no concerns, an AIA may not be required.

• Who conducts and pays for the AIA?

  The applicant is responsible for hiring a qualified underwater archaeologist and covering the cost of the work. The archaeologist must obtain a Parks Canada Research and Collection Permit before starting the assessment.
• Can Parks Canada recommend an archaeology consultant?

  No. Parks Canada cannot provide referrals or endorse specific consultants.

  Applicants should seek qualified underwater archaeologists through professional associations such as:

  • The Canadian Archaeological Association (CAA);
  • The Ontario Archaeological Society (OAS); or
  • Provincial directories of licensed archaeologists.
• What qualifications should the consultant have?

  The archaeologist should have:

  • A master’s degree in underwater archaeology or in archaeology with significant underwater experience;
  • Proven experience identifying historic and Indigenous sites and artifacts in Ontario;
  • Obtained a valid Parks Canada Research and Collection Permit for the proposed work.
• How much does an Archaeological Impact Assessment cost?

  Costs vary widely depending on site size, water depth, accessibility, and survey methods. Applicants should obtain quotes directly from consultants, but typical underwater AIAs can range from several thousand to tens of thousands of dollars for larger or complex sites.
• Does submitting an AIA guarantee my dredging permit will be approved?

  No. An AIA provides information to help Parks Canada evaluate your application, but it does not guarantee approval. If the study identifies significant cultural resources that could be harmed, the proposed dredging may be modified or denied.
• The bed fronting my property was previously dredged. Does that mean an AIA is not required?

  Not necessarily. Previous dredging may reduce archaeological potential, but Parks Canada will still review your site. An AIA may still be required if:

  • Records of past dredging are unavailable or incomplete; or
  • The area exceeds 12 m² and may contain undisturbed sediments.
• I plan to dredge every 5, 10, or 20 years. Do I need a new permit and AIA each time?

  Yes. Each dredging event requires a new permit and review under current regulations and environmental requirements. If the area and scope of work remain unchanged, the previous AIA may be referenced, but Parks Canada will determine whether a new assessment is needed.
• I have an inland wetslip, boathouse, or boatport. Do I need a permit and AIA to dredge within it?

  Yes. Dredging within an enclosed or inland area still involves disturbing the bed of the Waterway and requires a permit. Whether an AIA is needed depends on the site’s disturbance history and archaeological potential.
• I have a boathouse or boatport on the lake or riverbed. Do I need a permit and AIA to dredge inside it?

  Yes. Dredging inside a structure built over the lake or riverbed requires a permit from Parks Canada. An AIA may be required if the location has not been previously disturbed or assessed and/or the dredge exceeds 12 m².
• What are the limits on dredging fronting my residential property?

  To reduce impacts:

  • An area no wider than 25% of a property’s shoreline length, up to 15 metres (50 feet), may be dredged.
  • A single boat channel may not exceed 6 metres (20 feet) in width.
  • A shared channel among neighbouring properties may not exceed 8 metres (26 feet).
  • Dredging depth and footprint must be minimized.
• What are the limits on dredging fronting a commercial, municipal or governmental property?

  To reduce impacts:

  • Dredge only areas of existing use.
  • Depth and footprint of dredge must be minimized.
• Are there environmental protection measures I must follow?

  Yes. Environmental mitigation measures are mandatory, including:

  • Installing and maintaining a silt or turbidity curtain around the work area;
  • Placing dredged material at least 15 metres (50 feet) from the shoreline, above the floodplain, and stabilizing it;
  • Avoiding vertical dredge edges to allow natural stabilization;
  • Avoiding fish spawning and nursery areas;
  • Obtaining authorization for nighttime or winter dredging, if proposed.
• Can I remove logs, stumps, or rocks from the bed of the waterway?

  No. These materials may not be removed as they provide important fish habitat and may have cultural or archaeological value. In some cases, Parks Canada may allow them to be relocated fronting the same property in an area of similar water depth.
• Will I need to provide an environmental impact assessment for my residential dredge permit application?

  No. Parks Canada will administer the environmental impact assessment to determine if the dredging activity may have adverse effects on the environmental heritage of the site.
  
  Note: commercial and municipal projects are required to provide an environmental IA as part of the permit application.
• Who can I contact for more information or help with my dredging application?

  Parks Canada – Ontario Waterways
  2155 Ashburnham Drive, P.O. Box 567
  Peterborough, ON K9J 6Z6
  Tel: 705-750-4900 | Toll-free: 1-888-773-8888
  Email: on-tsw-vnts.permits-permis@pc.gc.ca

• Where can I find the policies and application forms?

  Visit:

  • Online In-water and Shoreline Works Permit Application
  • Policies for In-water and Shoreline Works and Related Activities