Background: Canadian Forces Base (CFB) Esquimalt is located at the south end of Vancouver Island, BC, and is the primary Pacific homeport for the Royal Canadian Navy (RCN). CFB Esquimalt is in a significant era of transformation to ensure it effectively supports the RCN into the 21st Century. Two significant marine projects forming part of this transformation are the A/B Jetty Recapitalization Project and the Small Boat Float Project. These projects require significant environmental oversight to protect the marine environment.
Approach/Activities: Construction activities related to the A/B Jetty and Small Boat Float projects have a potentially marked impact on aquatic life including marine mammals, fish, shellfish, and kelp. A harbour-wide remediation project is also underway to address contamination associated with historic use of the harbour. With deconstruction taking place to allow for new infrastructure, remedial actions have taken advantage of the removal of structures to address the contamination in a number of ways.
Activities in these two projects include: jetty deconstruction, underwater bedrock blasting, sediment and rock dredging, shoreline reinforcement and pile installation. A series of environmental studies and assessments were prepared for both projects to successfully obtain authorizations from Fisheries and Oceans Canada (DFO). Based on these documents and the authorizations, intensive mitigation measures have been put in place in collaboration with stakeholders and regulators to ensure the marine environment is protected. Artificial reefs were created in advance of construction to offset habitat losses, kelp was salvaged and relocated, and a fish salvage was completed prior to construction start. During construction, marine biologists measured underwater noise levels along with on-going fish and marine mammal monitoring. Water quality monitoring plans were developed based on sediment contamination.
As new information was collected it became clear that some in-water work restrictions needed updating based on information collected during the underwater test-blasting program. One significant challenge was the presence of harbour seals within the 200m pinniped exclusion zone. These seals are generally curious and accustomed to life in an industrial harbour, resulting in some blasts being postponed by several hours or even a day. Following test blasting, project consultants completed an evaluation of the underwater noise thresholds which included a review of currently-available science and marine mammal acoustic thresholds being used in other jurisdictions. Based on this review and the data collected during test blasting, the projects were able to provide adequate rationale to DFO to adopt the more current NOAA 2018 underwater noise limits for marine mammals while reducing the required exclusion zone for pinnipeds from 200m to 100m. This resulted in reduced blast delays, project construction costs and schedule impacts while still ensuring marine mammals are protected.
Lessons Learned: Using an adaptive management approach, modifications to mitigation measures have occurred proactively during construction. Key examples include: adjusting underwater noise thresholds to align with new research/guidance while still protecting marine mammals; refinement of fish salvage at various stages of project implementation; and, field trials to further evolve fish detection and fish exclusion techniques to reduce the impact of underwater blasting on fish.
Shauna Davis, Environmental Services Coordinator, Defence Construction Canada Shauna Davis is an Environmental Services Coordinator with Defence Construction Canada (DCC) at CFB Esquimalt in Victoria, BC. Shauna has over 19 years of experience in the environmental industry, working on private industry and government projects both as a consultant and with DCC. Shauna is currently the DCC Deputy Project Manager for the Esquimalt Harbour Remediation project and the environmental coordinator for the Small Boat Floats project at CFB Esquimalt, working with consultants, DND and stakeholders to develop project plans and specifications while following the programs through to implementation to ensure the work is completed in compliance with environmental mitigation, monitoring and regulatory requirements.
Becky MacInnis, Environment Officer, Department of National DefenceBecky MacInnis, B.Sc., P.Chem., P.Ag is an Environment Officer with the Department of National Defence (DND) at Canadian Forces Base (CFB) Esquimalt in Victoria, BC. She has over 14 years of experience in the environmental industry, the majority of which has been spent working on federal government projects both as a consultant and with Defence Construction Canada (DCC) and DND. Becky provides environmental support to the Royal Canadian Navy at CFB Esquimalt, including major capital construction projects, to ensure activities are completed in compliance with environmental mitigation, monitoring and regulatory requirements.