ANNEX A: Natural Watercourse and Shoreline Development Permit Area Review for a Dock Piling Replacement at 335 Stewart Ave

RE: Natural Watercourse and Shoreline Development Permit Area Review for a Dock Piling Replacement at 335 Stewart Ave, Victoria, BC, Town of View Royal

On 28 May and 1 October 2020, Lehna Malmkvist, MSc, RPBio. of Swell Environmental Consulting Ltd. (Swell) visited the site at 335 Stewart Avenue, Victoria, BC to evaluate the existing condition of the property in reference to a proposed dock piling replacement within the Town of View Royal’s Natural Watercourse and Shoreline Areas Development Permit Area (Figure 1), additionally, Dr. Joachim Carosfeld, Executive Director, World Fisheries Trust reviewed video of the site to assess the existing condition and potential environmental impact of the proposed works (see report in Appendix 1). The underwater video was filmed by Lee Critchley, CHL Timberworks on September 25, 2020. (https://gopro.com/v/zPnrL12wvM7OR). As per View Royal’s Schedule Q of the Official Community Plan (2011) Bylaw No. 811, the site was assessed for sensitive ecosystems, red and blue listed species, wildlife trees, and all environmentally sensitive areas within the site. This Environmental Impact Assessment summarizes our assessment of the environmental conditions at the property and potential impacts from the proposed dock piling replacement construction work zone.

Natural Watercourse and Shoreline Areas Development Permit Area, Bylaw No. 811

The View Royal Official Community Plan (OCP 2011) Bylaw No. 811, identifies the following Guidelines from the Natural Watercourse and Shoreline Areas DPA that apply to this project:

• Docks and wharves should be sited to avoid impacts on sensitive ecosystems such as eelgrass beds, fish habitat, and natural processes such as currents and littoral drift.
• Piers and pilings and floating docks are preferred over solid-core piers.
• Docks should be constructed of stable materials that will not degrade over time. The use of unenclosed plastic foam or the use of creosote treated pilings is strongly discouraged.

Proposed Works

The owner is proposing to replace one creosote piling with a 12” steel piling. The current piling is creosote and is degraded and needs replacing for stability of the dock (Photos 1 and 2). No concrete work is proposed.

The proposed work is to use a vibratory hammer to minimize disturbance area to:

• remove the existing piling
• insert the new piling into the hole from the existing piling

The owner has stated that they are communicating with Department of National Defense for the work in Limekiln Bay, part of Esquimalt Harbour, and a DFO Project Review will be submitted, and the proposed work will follow the DFO “Best Management Practices for Pile Driving and Related Operations”(Appendix 2) to minimize the risk and prevent impacts to marine fish and their habitat.

Figure 1. Airphoto showing location of proposed piling for replacement. Airphoto courtesy of Capital Regional District Web Map

Site Conditions

The site of the proposed work is in the subtidal area adjacent to 335 Stewart Ave, in the vicinity of the existing dock. Dr. Joachim Carosfeld, Executive Director, World Fisheries Trust reviewed video of the site to assess the existing condition and potential environmental impact of the proposed works (see photos and report in Appendix 1). The underwater video was filmed by Lee Critchley, CHL Timberworks.

The work will take place approximate 15m from the shoreline, in approximately 4 metres water depth.

Dr. Carosfeld, described the site as follows:

The location is at the mouth of Limekiln Bay, part of the Esquimalt Harbour, an area characterized in the CRD Harbours Atlas (Fig. 3). In general, this is a bedrock and boulder shoreline, with pocket beaches, leading to a shallow soft bottom. The site evaluation confirmed this general character – a bedrock and boulder-rich steep shoreline extends approximately 2 m (horizontally) from the highest High tide line, reaching a sandy mud bottom at a depth of 1.1-1-8 m. The mud bottom extends at a low slope into the harbor, in this assessment to a depth of 4.2 m., with scattered debris, rocks, and patches of gravel.

The subtidal boulder region is dominated by sea lettuce (Ulva lactuca) in shallow water, progressing to large leafy kelp (Laminaria groenlandica). This kelp is also abundant on the dock and, as large plants, in one of the transects with more debris and rocks on the mud bottom, extending to the end of survey. A similar fringed kelp, Agarum fimbriatum, is likely mixed in with this, particularly in deeper water. Otherwise, the sandy mud bottom has a thick diatom biofilm, pock-marked by active clam and worm burrows (Fig. ..), with Laminaria kelp and plumose anenomes (Metridium spp.) attached to debris.

Some clumps of Gracilaria filamentous red algae and drift sea lettuce (Ulva) are present, Dungeness crabs are common (Cancer magister), and a mottled seastar (Evasterias troschelli) was observed. Judging from the excavation marks in the sand, the crabs (including the similar Cancer gracilis – graceful rock crab) and different species of clam digging seastars are likely present in transient fashion. A school of juvenile herring was observed, but no other fish. Small fish and shrimp are nevertheless likely present in the Laminaria kelp bed. No eelgrass is reported for the head of Limekiln Bay, but was considered of patchy occurance in Esquimalt Harbour (AMR, 2004). None was observed at this site, likely because it is too deep.

The existing pilings are also covered with diatom film and barnacles, with scattered plumose anenomes and colonial tunicates.

Impact of Proposed Development

Following completion of the site assessment, Dr. Carosfeld, determined (Appendix 1):

No eelgrass was observed in the project area. The sandy mud bottom, with rich clam resources and Laminaria kelp bed, are typical of this region and widespread. Piling replacement, assuming adequate control of creosote leakage during removal, should not affect any sensitive habitats.

Recommendations and Best Management Practices (BMPs)

A dock is existing at 335 Stewart Avenue and the proposed dock piling replacement would have a minimal effect on the ecological conditions of the subtidal area in the vicinity of the work, and removal of the existing degrading creosote pile will be a benefit to the marine environment.

In addition to any requirements within the issued federal and provincial permits, the following Best Management Practices are recommended to ensure minimal risk to the DPA:

• Marine construction activities are restricted to the following Reduced Risk Timing Windows in order to ensure that significant harm does not occur to fish or fish habitat, as per Fisheries and Oceans Canada under the federal Fisheries Act:
  • Summer Window: July 1 – August 1
  • Winter Window: December 1 – February 15
• Minimize the duration of in-water work.
• Avoid in-water works during periods of adverse weather.
• A silt curtain must be on-site and deployed around the in-water works, if recommended by the environmental monitor.
• If a vibrohammer is not used, and impact pile driving is required, the Contractor must engage hydroacoustic monitor during pile installation.
  • Contractor must have access to bubble curtain, if needed, to mitigate the pressure in excess of the levels described below.
• Erosion & Sediment Control and Spill Prevention & Response measures must be implemented to protect the marine ecosystem from construction activities:
  • Remove and properly dispose of all wastes associated with piling installation;
  • Spill response kits will be on site when heavy machinery is working, and operators trained in their use;
  • Equipment will be inspected for leaks prior to beginning work.
• Submit a Project Review to DFO concurrently with the Development Permit Application and implement any additional recommendations provided.
• Establish separate fish and marine mammal exclusion zones prior to impact pile driving and monitor the zones for the presence of fish for at least 10 minutes and for marine mammals for at least 30 minutes prior to the start of impact pile driving.
  • Conduct pile driving during daylight hours and when weather conditions permit visual assessments for marine mammals in the exclusion zones.
  • If fish and marine mammals are not observed in the respective exclusion zones during the pre-start period, a soft start procedure is recommended where the energy is gradually increased over a 10 minute period. The soft start procedure is also recommended anytime after there is a break of 30 minutes or more during impact pile driving.
  • If a marine mammal enters the marine mammal exclusion zone, temporarily suspend impact pile driving until the individual has left the exclusion zone or has not been sighted for 30 minutes.
  • The recommended sound thresholds are 206 dB re: 1 μPa and a SELcum of 186 dB re: 1 μPa2s at the boundary of the fish exclusion zone and 160 dBRMS re: 1 μPa at the boundary of the marine mammal exclusion zone.
  • If hydroacoustic monitoring indicates that these thresholds are being exceeded, impact pile driving should cease and only resume after additional mitigation measures (e.g., bubble curtain) are implemented to effectively reduce sound levels below the thresholds.
• BMPs from the DFO “Best Management Practices for Pile Driving and Related Operations”(Appendix 2) will be implemented during pile removal and installation unless directed otherwise by DFO, some of the key BMPs for this project include:
  • During removal of the creosote piling, the contractor will remove the piling by mechanical means and avoid breaking the piling at the mud line or below, to ensure the contractor will extraction of the entire length of the pile from the ground or seabed. All demolition operations should be monitored in order to control and contain the construction debris and to determine whether there are any effects on fish. All debris from pile removal must be disposed of at an appropriate upland disposal site in accordance with all applicable legislation.
  • Contractors must position their vessels and water borne equipment associated with pile driving activities in a manner that will prevent damage to fish habitat (e.g. eelgrass, kelp beds, shellfish beds, salt marshes, etc.).
  • Pipe piles must be capped or otherwise treated to prevent birds from being trapped inside the piles.
  • All equipment will be maintained in good proper running order to prevent leaking or spilling of potentially hazardous or toxic products. This includes, but is not limited to, hydraulic fluid, diesel, gasoline and other petroleum products.
  • All hydrocarbon products (fuel, oil, hydraulic fuel, lubricants), fueling equipment, and deleterious substances must be stored and handled in accordance with all applicable legislation, guidelines and BMP’s. An appropriate spill prevention, containment and cleanup contingency plan for hydrocarbon products and any other deleterious substances that may be used or transported to the project site, must be in place prior to work commencing on the project to ensure that spills are contained and prevented from entering the marine environment.
  • Contractors will have emergency spill equipment available whenever working near or on the water. The emergency spill equipment should be appropriate for the specific operation (e.g., pouring concrete, refueling, etc.) and environmental conditions (e.g., marine, riverine, etc.) and equipment operators should be trained in their deployment and use.
  • All work areas must be adequately contained to prevent the release of demolition and construction debris and materials and any deleterious substances to the marine environment. All construction/demolition debris must be contained, collected and disposed of in an appropriate upland facility in accordance with existing legislation, guidelines and best management practices. Demolition operations should be monitored to determine whether the works are resulting in any adverse effects on fish or fish habitat. Any adverse effects should be reported to DFO.
  • Without restricting the generality of the foregoing paragraph, with respect to the discharge or introduction of sediment, sediment-laden water, and turbid water into the marine environment, the following criteria must be complied with:
    • Total Suspended Solids (TSS):
      • TSS should not exceed 25 mg/L
    • Turbidity:
      • Turbidity should not exceed 2 nephelometric units (NTU) when background is less than 8 NTU.
      • Turbidity should not exceed 8 NTU when background is between 8 and 80 NTU.
      • Turbidity should not exceed background by more than 10% when background is greater than or equal to 80 NTU.
      • “Background” is defined as the level at an appropriate adjacent reference site, that is satisfactory to DFO, and is affected neither by works or activities associated with the project or the works site, nor by sediment-laden water, induced suspended sediments, or induced turbidity resulting from works or activities associated with the project or the work site.
      • Should the project result in TSS or NTU levels in excess of the criteria outlined above, then those works and activities that might be contributing to these conditions must be halted until measures that will ensure compliance with the criteria outlined above are put in place.
      • Where the suspended solids and turbidity criteria outlined above cannot be practicably achieved, work areas and those works and activities that might be contributing to these conditions must be contained and isolated from tidal and flowing waters such that fish are prevented from accessing the work areas, and sediments, sediment-laden water, and turbid water are contained and prevented from leaving the work areas.
  • The contractors must ensure that pile driving associated with the project does not result in underwater noise or increases in underwater peak pressures that would adversely affect fish. Increase in underwater peak pressures in excess of 30 kilopascals (kPa) are likely to adversely effect fish.
  • Any proposed pile driving activity that may result in pressure effects of greater than 30 kPa (e.g. steel piles and power hammer) must incorporate mitigation measures specifically intended to prevent increases in underwater peak pressures in excess of 30 kPa anywhere greater than 1 metre from the pile being driven from adversely affecting fish. Mitigatory measures that might be appropriate include:
    • The use of smaller diameter pipe pile.
    • The use of a vibrating hammer or non-power drop hammer.
    • Scheduling the works outside of periods of heightened sensitivity with respect to fish (e.g., periods of juvenile salmon seaward migration, periods of adult salmon upstream migration to local watercourses; periods of herring spawning)
    • The deployment of netting, or "silt curtains" to isolate the work area and prevent fish from entering any area where the pile driving shock wave might exceed 30 kPa.
    • The deployment of a "bubble curtain" of sufficient design to surround the entire length of each pile being driven and attenuate shock waves radiating out from the pile so that overpressures outside the bubble curtain do not exceed 30 kPa.
  • To ensure that mitigation measures are effective, a hydrophone must be deployed to measure in-water pressure changes resulting from pile driving, monitor the effectiveness of mitigatory measures in use (e.g., isolation curtains, bubble curtains), and to determine the need for further mitigatory measures
  • The deployment of a hydrophone to measure in-water pressure changes resulting from pile driving. Hydrophone measurements should be carried out over the entire course of pile driving, particularly during driving to resistance or seating in bedrock. Hydrophone measurements should include depth profiles taken at a range of distances radiating out from the pile being driven. Each hydrophone depth profile should include measurements taken near the water surface, near the seabed, and at mid water column. The range of distances for hydrophone depth profiles should include a depth profile within 2 metres of the pile. The continual monitoring of shock wave pressure during pile driving is necessary to monitor the effectiveness of mitigatory measures in use (e.g., isolation curtains, bubble curtains), and to determine the need for further mitigatory measures.
  • Any proposed pile driving activity that may result in pressure effects of greater than 30 kPa (e.g. steel piles and power hammer) must be monitored by an appropriately qualified professional who is familiar with pile driving activities (including the potential affects on fish and the measures required to mitigate these affects) to ensure that effective measures are applied to mitigate adverse affects to fish and that all activities are conducted in accordance with the Fisheries Act. Monitoring must utilize hydrophones operated by appropriately qualified professionals. Pressure levels should be recorded at a range of depths throughout the water column and at varying distances and directions form the driven pile. Monitoring should be carried out throughout the pile driving from beginning to end for various piles and soil conditions and particularly during periods of heavy pile driving or pile refusal.
  • The hydrophone monitoring may be discontinued if the experience with the first 4 or 5 piles shows that the particular pile installation method in use does not result in overpressure of 30 kiloPascals (kPa), when readings are taken 1 metre from the pile being driven, and there have not been any observations of distressed or injured fish. This would only be applicable in situations where future pile driving associated with the project will use the same equipment, methods, type of piles, size of piles and the substrate that the piles are being driven into has the same characteristics as the substrate the test piles were driven into.
  • All work must be suspended and further mitigation measures need to be employed to reduce the pressure wave (e.g. bubble curtain) if pile driving activities result in hydrophone readings in excess of 30 kPa, measured 1 metre or further from the pile being driven or should there be any sign of dead or injured fish within the work area. DFO must be consulted prior to proceeding with pile driving activities.
  • Vibratory hammer must be used wherever feasible, particularly when driving steel piles.
  • The contractor will provide a hydrophone for monitoring the pressure during the piling installation and will

Environmental Monitoring

• A Qualified Environmental Professional (QEP) will monitor the piling installation, including a pre-construction meeting with the contractor, and monitoring for sediment releases, spills, water quality, and pressure within the marine environment.
• The Environmental Monitor must be on site at all times during the course of the project whenever there is the potential for adverse effects or fish or fish habitat.
• Upon completion of the project, the Environmental Monitor will provide DFO with a monitoring report summarizing the project and describing any environmental issues that arose during the project. Monitoring results should be forwarded to the appropriate contact at DFO’s Oceans, Habitat and Enhancement Branch.
• If contractors are working and a herring (or other fish) spawning occurs or if there are any negative impacts to fish or fish habitat, the work will be suspended until the appropriate DFO contact has been notified and has provided direction.

Provided the Best Management Practices above are followed, the applicable guidelines for the Development Permit Area are expected to be met, and we do not expect the proposed construction activities to have any negative impacts to the current ecosystems of the 15-m DPA setback or subtidal marine environment.

In summary, the proposed work will not disturb any rare or endangered species or ecosystems and provided the measures described in this review are followed, the effects of the project on the marine environment and shoreline conditions are minimal.

Please do not hesitate to contact us with any questions you may have.

Sincerely,

Lehna Malmkvist, MSc, RPBio (#1613)

Photo 1. Above water photo of piling to be replaced.

Photo 2. Underwater photo of piling to be replaced.