The Fundy Ocean Research Centre for Energy proposes to construct, operate and decommission a Tidal Energy Demonstration Facility in the Minas Passage, near Parrsboro, Nova Scotia.
The objectives of the Demonstration Facility are:
- To build and operate a tidal energy Demonstration Facility to test the commercial potential of in-stream tidal energy devices designed to convert tidal kinetic energy to electrical energy;
- To acquire information necessary to assess the performance of tidal energy devices including their effect on the environment and the effect of the environment on the devices; and,
- To develop monitoring techniques and methodologies for these devices in the tidal environment.
The Facility will consist of three subsea turbine generators, individual subsea cables connecting the turbines to land-based infrastructure, an onshore transformer substation, and buried power lines connecting to the local power distribution system (the Project). This Project is subject to a screening level Environmental Assessment under the Canadian Environmental Assessment Act and is a Class 1 Undertaking under provincial regulations. The Environmental Assessment will be reviewed jointly under the terms of the Federal-Nova Scotia Environmental Assessment Agreement.
This Environmental Assessment Document addresses the potential impacts associated with the Demonstration Project only, and relates to the deployment of three turbine generators. It does not address or predict the impacts of a larger array of turbine generators or a commercialization level project, as these projects would require a separate Environmental Assessment process. It is anticipated that some of the information gained from the environmental effects monitoring for the Demonstration Project can be used by researchers to model and predict potential impacts of scaled-up developments.
The demonstration turbines will be located within a Crown Lease on the seabed in the vicinity of Black Rock on the north side of the Minas Passage, approximately 1.25 km from shore. The generators (with the possible exception of the Minas Basin Pulp and Power/ Marine Current Turbines unit) will be installed on gravity bases, rather than drilled foundations. The units will be installed on the seabed in approximately 30 - 45 m depth at low tide.
The Clean Current 2.2 MW model is approximately 18 m in length and has an outside diameter of approximately 20 m. The Nova Scotia Power/OpenHydro turbine is rated to 1 MW and the total diameter is 10 m with a 4 m diameter open centre. The MBP&P/Marine Current Turbine unit is 1.0 - 1.2 MW and will consist of twin axial flow rotors approximately 15 m in diameter. The MCT turbine will either be mounted on a steel gravity based structure or steel pin pile foundations in the seabed. A visible portion of the turbine's support structure will project approximately 21.5 m above the sea surface at low tide. The total capacity of the three devices together will be approximately 4.4 MW.
The Crown Lease will also include a 1.25 km long cable corridor connecting the generators to a land based facility above the high water mark. The terrestrial facility will be built on land leased from a private landowner and will consist of an underground vault to receive the submarine cables, a small building housing electrical switchgear and an interpretive centre, a parking area, a transformer substation and an underground cable connection to the power lines along West Bay Road.
Deployment of the NSPI/OpenHydro turbine is scheduled for October, 2009 when construction of the onshore electrical facility will also begin. The onshore facility is expected to be connected to the electrical grid by summer 2010. Installation of the subsea cables is planned for late summer of 2010, and this will be combined with or followed shortly by installation of the two remaining turbines, which will be completed by mid-summer, 2011. The demonstration turbines will operate for one to four years, following which the turbines and their gravity bases will be removed.
Emissions and discharges are expected to be similar those associated with other marine and small terrestrial construction projects. Electromagnetic fields and noise associated with the turbines are less well understood and will require additional monitoring. Preliminary information suggests these emissions will have negligible impact due to the limited scale demonstration facility.
Studies undertaken in 2008 to characterise the sea bed included the use of high-resolution seismic reflection systems, sidescan sonar, multibeam bathymetric sonar and photographic surveys. For the most part, the deployment area consists of exposed and scoured volcanic and sedimentary bedrock with course gravel and boulders covering glacial-era muds that may remain between upturned sedimentary ridges. Moving toward shore, thick surficial sediments overlie the bedrock. The cable route has been selected to avoid areas of slump and regions of gravel bedforms.
Currents were measured over the lunar month using bottom mounted instruments three times at three different sites around the deployment area. The mean speed, mean velocity and maximum current speeds with the corresponding directions at specific water depths were measured at each site.
Information on benthic animal and seaweed communities was obtained from seabed video and still camera photography in August and September 2008, as well as from several bottom samples obtained by scallop dredge in August 2008. Four main types of benthic communities are described based on the substrate they inhabit. Benthic communities exhibit moderate diversity and abundance of organisms reflective of communities adapted to the particular environment at the Project site.
The Minas Passage/Minas Channel supports small commercial fisheries which tend to be fished from nearby. Inner Bay fisheries comprise primarily lobster, herring and soft-shell clams; however, many species in the Outer Bay also move in and out of the Inner Bays, and the Inner Bay may be an important nursery area for many species. Most lobster fishing takes place along the Blomidon, Scots Bay and Parrsboro shores, and is concentrated nearshore although traps are occasionally set in deeper, high current areas. Eleven lobster boats routinely fish in the Minas Channel/Passage (part of LFA 35) although considerably fewer are known to fish in the Project area.
There are no First Nations reserves in or immediately surrounding the Project area. The Fort Folly First Nation in Dorchester, New Brunswick operates commercial fishing vessels from Parrsboro Harbour. A Mi’kmaq Ecological Knowledge Study (MEKS) has been commissioned for completion by August 2009, and is jointly funded by FORCE and the province of Nova Scotia.
The largest and most frequent commercial vessels moving through the Minas Channel/Passage are exclusively gypsum bulk carriers with a maximum draft of 10 m when fully loaded, sailing at high tide or falling high tide. Gypsum vessels sail through the deepest part of the Minas Passage generally tending to the Cape Split (southern) side. The closest the shipping route approaches the edge of the Demonstration Deployment Area is 1 km.
A scoping exercise was undertaken to identify an appropriate list of Valued Ecosystem Components (VECs) upon which to focus the assessment. VECS were established based on a review of the Strategic Environmental Assessment Report and supporting Background Report, formal and informal discussions with provincial/federal regulatory agencies and government scientific authorities, a review of listed species and species at risk found within the Project area, discussions with stakeholders and First Nation/Aboriginal groups and the professional judgment of the Proponent’s Study Team. Following this process, the following VECs were retained for detailed analysis.
|Marine Benthos||Intertidal Environment|
|Marine Fish and Water Quality||Terrestrial Species at Risk|
|Marine Mammals||Recreational and Commercial Fishing|
|Marine Birds||Archaeological and Heritage Resources|
|Marine Species at Risk||Tourism and Recreation|
|Terrestrial Wildlife and Wildlife Habitat|
Each of the VECs was evaluated for potential interactions between the VEC and Project activities during all project phases as well as malfunctions or accidents that may occur. These interactions were evaluated for potential significance after application of technically and economically feasible mitigative measures. The cumulative effects of the proposed Demonstration Facility in conjunction with past, present and likely future projects were also evaluated. Environmental monitoring and follow-up measures are proposed and will be undertaken to ensure compliance with applicable regulations, standards and guidelines, to verify environmental effect predictions and refine mitigative measures, as well as to gather important information to further evaluate the potential for environmental effect s for future larger scale tidal energy projects ( i.e., commercialization).
With the implementation of the proposed mitigation measures including development and implementation of a detailed monitoring plan, adverse residual environmental effects of the Project are predicted to be not significant for all VECs. A positive effect is anticipated for recreation and tourism given the potential for an increase in ecotourism.
The Project will contribute to the goals established in the Provinces’ Renewable Energy Standards for the reduction of GHGs and dependence on fossil fuels for generating electricity. In addition, a demonstration project of this nature is required and has been recommended in the Strategic Environmental Assessment and the Background Report to gather valuable and much needed information to fully assess the potential environmental effects of tidal energy and tidal in-stream energy conversion technology as a renewable commercial energy source in the Bay of Fundy.