Management Measures Tool for Marine Energy

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Accessing Management Measures that Support Deployment of Wave and Tidal Energy Devices

As the marine renewable energy (MRE) industry moves beyond deployment of individual wave and tidal energy devices towards arrays, certain risks of MRE devices on the marine environment are not well understood and have led to onerous monitoring requirements placed on device developers.

A workshop was held in May 2017 with researchers, regulators, and developers to create the basis for the tool shown below. In consultation with the research and regulatory communities, it was agreed that applying a set of robust management measures could act as safeguards for marine animals and habitats until available monitoring data allows for determining the level of risk from MRE devices. At that point, measures could be dialed back or removed, if warranted. More information on the workshop and input for the tool can be found here.

The Management Measures Tool for Marine Energy shows management (or mitigation) measures from past or current MRE projects as a reference to help manage potential risks from future projects and allow them to move forward in the face of uncertainty, or until a risk can be retired. Additional management measures are regularly added by the OES-Environmental team. In addition to the searchable tool below, the information can be downloaded here. The download file includes additional details not shown below, including comments from stakeholders on past experience, cost of management measures, and when a management measure is needed.

View the instructions document for more in-depth details and examples on how to use the Management Measure Tool for Marine Energy or check out this webinar for an overview and demonstration of the tool. 

Last updated January 2023

Displaying 101 - 200 of 339 management measures
Technology Project Phase Stressor Receptor Management Measure Advantages Challenges Project Documents
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Fish
Mitigation

Selective structural and blade coatings (e.g., colors to aide detection).

Unknown implications, but possible that it will aid detection of subsea structures and help reduce risk.

Minimal one-off cost that can be easily planned for at the design stage.

Unknown and further research is needed.

This could result in 'attraction', increasing risk of collision.

Uncertainty around how animals use visual cues. Other sensory organs are often more important for fish.

...Read more

Unknown and further research is needed.

This could result in 'attraction', increasing risk of collision.

Uncertainty around how animals use visual cues. Other sensory organs are often more important for fish.

Use of such measures may be limited to conform with IALA standards.

Read less
Xodus Group 2019, EMEC Billia Croo Grid-Connected Wave Test Site
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Fish
Elasmobranch, large fish
Design feature, Monitoring

Install tension sensors on mooring lines.

Informs of problem with mooring lines allowing rectification.

Additional cost.

Would require control system integration.

Load from entangled animal is likely to be smaller than the device loading on the moorings.

Uncertainty of the efficacy of this measure.

Laminaria 2018, EMEC Billia Croo Grid-Connected Wave Test Site
Wave, Tidal Operation & Maintenance Changes in sediment dynamics

The potential wider or secondary effects (siltation changes or smothering) on protected or sensitive littoral habitat due to devices and associated moorings, support structures, or landfall cables.

Habitat
Benthic species
Monitoring

Periodic visual monitoring through the use of divers, drop down video, or intertidal shore surveys.

Help reduce uncertainty.

Technical and Health and Safety risks associated with periodic monitoring operation in close vicinity of infrastructure.

Power shut down potential.

Subsea static monitoring options require O&M.

GlaxoSmithKlineMontrose 2012, Xodus AURORA 2010, Davison and Mallows 2005, GSK Montrose Tidal Array, HS1000 at EMEC, Strangford Lough - MCT (SeaGen)
Wave, Tidal Installation, Decommissioning Habitat Loss

Direct loss of protected or sensitive sub-littoral seabed communities due to the presence of devices and associated moorings or support structures on the seabed.

Habitat
Benthic invertebrates, demersal fish
Mitigation

Use of locally sourced materials, for cable protection, of the same type as the habitat to be disturbed by cable installation.

Minimizes habitat loss as lost seabed is replaced with same material.

Wave, Tidal Operation & Maintenance Collision risk

Pontential risk of collision with device giving size and character of structure.

Marine Mammals
Design feature

Device components (e.g., transformer and power conditioning equipment) are designed internally.

Reduces potential for collision with external moving parts.

The Marine Institute 2016, Galway Bay Test Site
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Marine Mammals
Mitigation

Source vessels locally.

Reduce/remove risk of transfer and settlement of non-native species.

Argyll Tidal Demonstrator Project, PacWave South Test Site, Orbital Marine Power O2 at EMEC, Mocean Wave Energy Converter: Blue Horizon
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Displacement

Potential displacement of essential activities due to the presence of devices and associated moorings/support structures.

Reptiles
Design feature

Array/ mooring configuration designed to avoid migratory routes or other important sites

Minimizes risk of development creating displacement by avoiding migratory routes or other important sites.

May be inconsistent with optimal layout of the development for exploitation of the energy source.

Can be a costly measure when scaling up to larger arrays.

Aquamarine Power Ltd 2011, Davison and Mallows 2005, Oyster 800 at EMEC, Strangford Lough - MCT (SeaGen)
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for accidental or unplanned events which could lead to contamination of the marine environment.

Benthic
Mitigation

Material selection - lubricants, coolants, hydraulic fluids etc. selected with low ecotoxicity levels and biodegradable.

Reduces/removes risk of pollution from materials which may have escaped structure.

Use of lower toxicity materials may compromise performance or impact other technical issues (e.g. fluid changes).

Foubister 2005, MeyGen 2012, Xodus AURORA 2010, Foubister 2005, Davison and Mallows 2005, The Marine Institute 2016, THETIS Energy 2009, EMEC Fall of Warness Grid-Connected Tidal Test Site, MeyGen Tidal Energy Project , HS1000 at EMEC, Strangford Lough - MCT (SeaGen), Galway Bay Test Site, Torr Head Project
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Benthic
Mitigation

Establish and implement a Biofouling Management Plan.

Reduce/remove risk of transfer of non-native species.

Lack of industry specific guidance.

European Marine Energy Centre (EMEC) 2014, Xodus Group 2019, RSK Group 2012, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Billia Croo Grid-Connected Wave Test Site, West Orkney South Wave Energy Site
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for accidental or unplanned events which could lead to contamination of the marine environment.

Birds
Mitigation

Material selection - lubricants, coolants, hydraulic fluids etc. - selected with low ecotoxicity levels and biodegradable.

Reduces/removes risk of contamination/pollution from materials which may have escaped structure.

Use of lower toxicity materials may compromise performance or impact other technical issues (e.g., fluid changes.)

MeyGen 2012, Foubister 2005, Xodus AURORA 2010, Davison and Mallows 2005, The Marine Institute 2016, THETIS Energy 2009, MeyGen Tidal Energy Project , EMEC Fall of Warness Grid-Connected Tidal Test Site, HS1000 at EMEC, Strangford Lough - MCT (SeaGen), Galway Bay Test Site, Torr Head Project
Wave, Tidal Decommissioning Vessel disturbance

Potential for disturbance from project vessels.

Birds
Mitigation

Limit use of vessels, e.g. one vessel present with regular use of thrusters to maintain position.

Reduces potential disturbance effects.

Low 2012, MeyGen 2012, Atlantis Resources Corporation at EMEC, MeyGen Tidal Energy Project
Wave, Tidal Operation & Maintenance Displacement

Potential displacement of essential activities due to the presence of devices and associated moorings/support structures.

Fish
Design feature

Site selection (taking into account cumulative impact of other developments).

Minimizes risk of development causing displacement by avoiding migratory routes or other important sites.

ScottishPower Renewables 2012, Ness of Duncansby Tidal Array
Wave, Tidal Installation, Decommissioning Habitat Loss

Direct loss of protected or sensitive sub-littoral seabed communities due to the presence of devices and associated moorings or support structures on the seabed.

Fish
Demersal fish
Design feature

Cable protection management measures to ensure that any rock placement that is required will be kept to a minimum to reduce seabed disturbance.

Could reduce effects on sensitive habitats

Additional cost.

DP Energy Ltd. 2013, Federal Energy Regulatory Commission (FERC) 2020, West Islay Tidal Project Energy Park, PacWave South Test Site
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for accidental or unplanned events which could lead to contamination of the marine environment.

Habitat
Mitigation, Compliance

Management: Establish and implement a Contamination Control Plan/Ship Oil Contamination Emergency Plans (SOPEPs).

Compliance with International Maritime Organization (IMO) and Maritime Coastguard Agency (MCA) codes for the prevention of contamination.

Reduces risk of any contamination/pollution event and ensures that contingency plans are in place.

Demonstrates compliance with environmental management systems.

Foubister 2005, GlaxoSmithKlineMontrose 2012, MeyGen 2012, Davison and Mallows 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, South West of England Regional Development Agency (SWDRA) 2006, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, EMEC Fall of Warness Grid-Connected Tidal Test Site, GSK Montrose Tidal Array, MeyGen Tidal Energy Project , Strangford Lough - MCT (SeaGen), Kyle Rhea Tidal Stream Array Project, Wave Hub, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site, PacWave South Test Site
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Barrier to movement

Potential barrier to movement due to the physical presence of devices and associated moorings/support structures, cables and electrical equipment.

Marine Mammals
Monitoring

Monitoring of existing developments.

Reduces scientific uncertainty.

Can be complex and costly.

Aquamarine Power Ltd 2011, GlaxoSmithKlineMontrose 2012, Orbital Marine Power 2014, Oyster 800 at EMEC, GSK Montrose Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Displacement

Potential displacement of essential activities due to the presence of devices and associated moorings/support structures.

Marine Mammals
Mitigation

Employ an MMO during periods when noisy operations are likely to cause disturbance (e.g, all operations using a DP vessel).

SAE Renewables 2011, Orbital Marine Power 2010, Minesto 2016, Foubister 2005, European Marine Energy Centre (EMEC) 2014, Xodus Group 2019, Magallanes Renovables 2020, McGrath 2013, MeyGen 2012, DP Energy Ltd. 2017, Royal Haskoning 2012, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, THETIS Energy 2009, Davison and Mallows 2005, Atlantis Resources Corporation at EMEC, Pelamis Wave Power P2 Demonstration at EMEC, Minesto Holyhead Deep - Non-grid connected DG500, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Billia Croo Grid-Connected Wave Test Site, Magallanes Renovables ATIR at EMEC, Fair Head Tidal Array, MeyGen Tidal Energy Project , Fair Head Tidal Array, Oyster 800 at EMEC, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site, Torr Head Project, Strangford Lough - MCT (SeaGen)
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Vessel disturbance

Potential for disturbance from project vessels.

Marine Mammals
Mitigation

Care will be taken to avoid splitting up groups and mothers and young.

Reduces potential effects and is a relatively low cost measure.

European Marine Energy Centre (EMEC) 2020, Magallanes Renovables 2020, Aquatera 2017, Orbital Marine Power 2018, EMEC Scapa Flow Scale Wave Test Site, Magallanes Renovables ATIR at EMEC, Tocardo InToTidal at EMEC, Orbital Marine Power O2 at EMEC
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Reptiles
Mitigation

Establish and implement a Biofouling Management Plan.

Reduce/remove risk of transfer of non-native species.

Lack of industry specific guidance.

European Marine Energy Centre (EMEC) 2014, Royal Haskoning 2012, EMEC Fall of Warness Grid-Connected Tidal Test Site, Oyster 800 at EMEC
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Install cable protection or armour.

Foubister 2005, Federal Energy Regulatory Commission (FERC) 2020, EMEC Fall of Warness Grid-Connected Tidal Test Site, PacWave South Test Site
Wave, Tidal Installation Barrier to movement

Potential barrier to movement due to the physical presence of devices and associated moorings/support structures, cables and electrical equipment.

Birds
Design feature

Array/ mooring configuration designed to avoid migratory routes or other important sites.

Minimises risk of development acting as a barrier to movement by avoiding migratory routes or other important sites.

May be inconsistent with optimal layout of the development for exploitation of the energy source.

Can be a costly measure when scaling up to larger arrays.

Aquamarine Power Ltd 2011, Oyster 800 at EMEC
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in lost fishing gear or other equipment trapped on infrastructure.

Birds
Diving birds
Mitigation

Fisheries management: Agreement with fishermen not to fish near to the device, warning of the dangers of losing equipment.

Reduces potential for entanglement of fishing gear in mooring lines and thus potential for entanglement of marine animals.

Xodus Group 2019, EMEC Billia Croo Grid-Connected Wave Test Site
Tidal Operation & Maintenance Changes in water flow

The potential wider or secondary effects on protected or sensitive sub-littoral seabed due to removal or alteration of energy flow arising from devices and moorings or support structures.

Fish
Monitoring

Installation of ADCPs and turbulence sensors to better understand the baseline tidal flow conditions and hence the change in tidal flow due to presence of the device(s).

Reduce scientific uncertainty.

Tidal Energy Ltd 2008, Aquatera 2017, Ramsey Sound, Tocardo InToTidal at EMEC
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Fish
Migratory fish
Design feature

Use of 3-phase cables instead of DC cables.

Reduce the level of EMF to surrounding water column and therefore any potential effects

Potential commercial and technical feasibility issues - the cables used will largely depend upon the project requirements.

Some uncertainty as to the efficacy of this measure.

Wave, Tidal Operation & Maintenance Underwater noise

The potential effects from underwater noise generated by wave and tidal energy converters.

Fish
Monitoring

Measure noise generated by device(s) during operation to better understand the potential effects on sensitive species.

Measured noise levels can be correlated with threshold values of relevant species and baseline noise levels of the site to determine impact and need for adaptive management measures.

Can be complex and costly to undertake this type of monitoring in high energy environments.

Data and analysis have requirement for acoustic experts.

SAE Renewables 2011, European Marine Energy Centre (EMEC) 2019, Atlantis Resources Corporation at EMEC, EMEC Billia Croo Grid-Connected Wave Test Site
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Habitat
Benthic invertebrates
Design feature

Bundle cables together to reduce field vectors.

Reduce the level of EMF to surrounding water column and therefore any potential effects.

Less redundancy in system.

Potential commercial and technical feasibility issues.

MeyGen 2012, MeyGen Tidal Energy Project
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
Mitigation, Monitoring, Design feature

Install a 'detect and shut-down' system using active sonar and other appropriate monitoring equipment (e.g., Marine Mammal Detections Sonar System [MMDS]).

Could reduce/remove risk of collision with moving blades and enable a route through the consenting process, particulalrly at high sensitivity locations.

Could affect power production, is expensive to implement, and does not help reduce scientific uncertainty regarding the risk.

Uncertainty around effects of sonar on sensitive species.

Not certain how often ‘shut-downs’ would be required.

...Read more

Could affect power production, is expensive to implement, and does not help reduce scientific uncertainty regarding the risk.

Uncertainty around effects of sonar on sensitive species.

Not certain how often ‘shut-downs’ would be required.

Detection systems are currently insufficient to detect animals (in particular at array scale).

Reductions in power production, although small, would bring about uncertainty in the investment process.

Read less
Harrison et al. 2015, Orbital Marine Power 2010, European Marine Energy Centre (EMEC) 2014, Keenan et al. 2011, Davison and Mallows 2005, Xodus Group 2019, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Aquamarine Power Ltd 2011, Minesto 2016, Magallanes Renovables 2020, Churchill Barriers - Wave Overtopping and Tidal Flow Energy Capture, Pelamis Wave Power P2 Demonstration at EMEC, EMEC Fall of Warness Grid-Connected Tidal Test Site, Strangford Lough - MCT (SeaGen), Strangford Lough - MCT (SeaGen), EMEC Billia Croo Grid-Connected Wave Test Site, Kyle Rhea Tidal Stream Array Project, Oyster 800 at EMEC, Minesto Holyhead Deep - Non-grid connected DG500, Magallanes Renovables ATIR at EMEC
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in lost fishing gear or other equipment trapped on infrastructure.

Marine Mammals
Cetaceans
Mitigation

Fisheries management: Agreement with fishermen not to fish near to the device, warning of the dangers of losing equipment.

Reduces potential for entanglement of fishing gear in mooring lines and thus potential for entanglement of marine animals.

Xodus Group 2019, EMEC Billia Croo Grid-Connected Wave Test Site
Tidal Operation & Maintenance Changes in water flow

The potential wider or secondary effects on protected or sensitive sub-littoral seabed due to removal or alteration of energy flow arising from devices and moorings or support structures.

Reptiles
Monitoring

Installation of ADCPs and turbulence sensors to better understand the baseline tidal flow conditions and hence the change in tidal flow due to presence of the device(s).

Reduce scientific uncertainty.

Wave, Tidal Installation, Decommissioning Changes in sediment dynamics

Reduced visibility from altered water clarity associated with sediment mixing that can impact prey detection and obstruction avoidance.

Benthic
Mitigation

Best practice methodologies to reduce resuspension of sediment during cable burial or device foundation/mooring installation.

Foubister 2005, ScottishPower Renewables 2010, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, South West of England Regional Development Agency (SWDRA) 2006, Sustainable Energy Authority of Ireland (SEAI) 2011, Tidal Lagoon Power 2017, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, EMEC Fall of Warness Grid-Connected Tidal Test Site, Sound of Islay Demonstration Tidal Array, Kyle Rhea Tidal Stream Array Project, Wave Hub, Atlantic Marine Energy Test Site (AMETS), Swansea Bay Tidal Lagoon (SBTL), Galway Bay Test Site, PacWave South Test Site, Mocean Wave Energy Converter: Blue Horizon
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Bury cables where possible and viable.

Sustainable Energy Authority of Ireland (SEAI) 2011, Federal Energy Regulatory Commission (FERC) 2020, Atlantic Marine Energy Test Site (AMETS), PacWave South Test Site
Tidal Operation & Maintenance Changes in water flow

Modifications to prey distribution and abundance (to include for other receptors) resulting in changes to foraging behavior.

Birds
Diving birds
Design feature

Site selection.

Minimizes significance of interaction.

Argyll Tidal Limited 2013, ScottishPower Renewables 2012, Argyll Tidal Demonstrator Project, Ness of Duncansby Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Birds
Mitigation

Establish and implement a Biofouling Management Plan.

Reduce/remove risk of transfer of non-native species.

Lack of industry specific guidance.

European Marine Energy Centre (EMEC) 2014, EMEC Fall of Warness Grid-Connected Tidal Test Site
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Fish
Mitigation

Minimise turbine standstill periods.

Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Fish
Elasmobranch, large fish
Monitoring

Fishing debris detected during routine inspections of mooring lines and cables will be removed.

Remove/reduce risk of entanglement.

Low cost measure, implemented as part of standard O&M procedures.

Regular monitoring will benefit system performance in addition to addressing environmental risks (e.g., early detection of damage or failures in the system).

Wave, Tidal Operation & Maintenance Changes in sediment dynamics

The potential wider or secondary effects (siltation changes or smothering) on protected or sensitive littoral habitat due to devices and associated moorings, support structures, or landfall cables.

Habitat
Benthic species
Design feature

Micrositing of landfall cables and infrastructure to minimise the impact on sensitive habitats and species. Best practice techniques for cable installation, burial and protection.

Orbital Marine Power 2014, Craig 2008, OpenHydro and SSE Renewables 2013, DP Energy Ltd. 2013, South West of England Regional Development Agency (SWDRA) 2006, SSE Renewables 2011, ScottishPower Renewables 2012, DP Energy Ltd. 2017, Laminaria 2018, Sustainable Energy Authority of Ireland (SEAI) 2011, Tidal Lagoon Power 2017, OpenHydro Alderney, Brims Tidal Array, West Islay Tidal Project Energy Park, Wave Hub, Westray South Tidal Project, Fair Head Tidal Array, EMEC Billia Croo Grid-Connected Wave Test Site, Atlantic Marine Energy Test Site (AMETS), Swansea Bay Tidal Lagoon (SBTL)
Wave, Tidal Installation, Decommissioning Habitat Loss

Direct loss of protected or sensitive sub-littoral seabed communities due to the presence of devices and associated moorings or support structures on the seabed.

Habitat
Benthic invertebrates, demersal fish
Design feature

Site selection to avoid sensitive or protected sub-littoral seabed communities.

Could reduce/remove effects on sensitive habitats.

ScottishPower Renewables 2012, OpenHydro and SSE Renewables 2013, Ness of Duncansby Tidal Array, Brims Tidal Array
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
Diving birds
Mitigation

Design proportion of swept area to structure area to minimise collision risk.

Could reduce the likelihood/consequence of potential collision events.

Can be a high cost associated with this.

Can present financial, logistical, or design challenges to technology developer to alter design of device.

MeyGen 2012, MeyGen Tidal Energy Project
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Marine Mammals
Compliance

Compliance with all relevant guidance (including IMO guidelines) regarding ballast water management and transfer of non-native species.

Reduce/remove risk of transfer and settlement of non-native species.

McPherson 2015, MeyGen 2012, Davison and Mallows 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Magallanes Renovables 2020, Federal Energy Regulatory Commission (FERC) 2020, Nova Innovation - Shetland Tidal Array, MeyGen Tidal Energy Project , Strangford Lough - MCT (SeaGen), Kyle Rhea Tidal Stream Array Project, Magallanes Renovables ATIR at EMEC, PacWave South Test Site
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Reptiles
Sea turtles
Design feature

Maintain taut mooring lines.

Remove/reduce risk of entanglement.

Regular inspections can provide operational insight into condition and track events.

Mooring design driven by technical and commercial consideration.

Regular ROV/dive or drop-down camera inspections required.

Aquatera Ltd 2011, Wello Penguin at EMEC
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for accidental or unplanned events which could lead to contamination of the marine environment.

Benthic
Mitigation

Where rock placement is used, ensure clean rock is used.

Reduces/removes risk of contamination/pollution from materials.

Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Benthic
Compliance

Adhere to appropriate measures when jettisoning ballast water.

Reduce/remove risk of transfer of non-native species.

Sustainable Energy Authority of Ireland (SEAI) 2011, Atlantic Marine Energy Test Site (AMETS)
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for accidental or unplanned events which could lead to contamination of the marine environment.

Birds
Mitigation

Where rock placement is used, ensure clean rock is used.

Reduces/removes risk of contamination/pollution from materials.

Wave, Tidal Installation, Operation & Maintenance, Decommissioning Vessel disturbance

Potential for disturbance from project vessels.

Birds
Birds on water
Mitigation

Vessel speed limitation to and from site.

Reduces potential effects.

Relatively low-cost measure.

SAE Renewables 2011, OpenHydro and SSE Renewables 2013, Atlantis Resources Corporation at EMEC, Brims Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Displacement

Potential displacement of essential activities due to the presence of devices and associated moorings/support structures.

Fish
Mitigation

Timing of installation and decommissioning & marine operations to avoid times of particular sensitivity (e.g. breeding).

Minimizes risk of development causing displacement by avoiding works during sensitive times.

Can be disruptive and hence costly to developer.

OpenHydro and SSE Renewables 2013, Aquatera Ltd 2011, Foubister 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, SSE Renewables 2011, ScottishPower Renewables 2012, McGrath 2013, Orbital Marine Power 2014, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, THETIS Energy 2009, ScottishPower Renewables 2012, Brims Tidal Array, Wello Penguin at EMEC, EMEC Fall of Warness Grid-Connected Tidal Test Site, Kyle Rhea Tidal Stream Array Project, Westray South Tidal Project, Fair Head Tidal Array, Galway Bay Test Site, PacWave South Test Site, Torr Head Project, Ness of Duncansby Tidal Array
Wave, Tidal Installation, Decommissioning Habitat Loss

Direct loss of protected or sensitive sub-littoral seabed communities due to the presence of devices and associated moorings or support structures on the seabed.

Fish
Demersal fish
Mitigation

Use of locally sourced materials, for cable protection, of the same type as the habitat to be disturbed by cable installation.

Minimizes habitat loss as lost seabed is replaced with same material.

Wave, Tidal Installation Contamination

Accidental release of contaminants during installation including diesel fuel, oil hydraulic fluids, etc.

Habitat
Mitigation

Best practice methodologies to reduce risk of accidental release of contaminants.

Reduces risk of contamination/pollution escaping from structure.

DP Energy Ltd. 2013, West Islay Tidal Project Energy Park
Wave, Tidal Installation, Decommissioning Changes in sediment dynamics

Reduced visibility impacting prey detection and obstruction avoidance.

Marine Mammals
Mitigation

Best practice methodologies to reduce resuspension of sediment during cable burial or device foundation/mooring installation.

Foubister 2005, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, EMEC Fall of Warness Grid-Connected Tidal Test Site, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site, PacWave South Test Site
Wave, Tidal Operation & Maintenance Displacement

Potential displacement of essential activities due to the presence of devices and associated moorings/support structures.

Marine Mammals
Design feature

Site selection (taking into account cumulative impact of other developments).

Minimizes risk of development causing displacement by avoiding migratory routes or other important sites.

ScottishPower Renewables 2012, Ness of Duncansby Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Vessel disturbance

Potential for disturbance from project vessels.

Marine Mammals
Mitigation

Vessel speed limitation to and from site.

Reduces potential effects and is a relatively low cost measure.

Aquamarine Power Ltd 2011, SAE Renewables 2011, Oyster 800 at EMEC, Atlantis Resources Corporation at EMEC
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Reptiles
Mitigation, Compliance

Adhere to appropriate measures when jettisoning ballast water.

Reduce/remove risk of transfer of non-native species.

Sustainable Energy Authority of Ireland (SEAI) 2011, Atlantic Marine Energy Test Site (AMETS)
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Use of 3-phase cables instead of DC cables.

Reduce the level of EMF to surrounding water column and therefore any potential effects.

Potential commercial and technical feasibility issues.

Uncertainty around the need for and efficacy of this measure.

Tidal Energy Ltd 2008, Ramsey Sound
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Barrier to movement

Potential barrier to movement due to the physical presence of devices and associated moorings/support structures, cables and electrical equipment.

Birds
Mitigation

Adherence to vessel management plan.

Minimizes the potential interaction between animals and construction or maintenance vessels.

OpenHydro and SSE Renewables 2013, Aquatera 2017, ScottishPower Renewables 2010, Brims Tidal Array, Tocardo InToTidal at EMEC, Sound of Islay Demonstration Tidal Array
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Birds
Diving birds
Design feature

Cable design with maximum bend radius.

Remove/reduce risk of entanglement

Mooring design driven by technical and commercial consideration.

Foubister 2005, EMEC Fall of Warness Grid-Connected Tidal Test Site
Tidal Operation & Maintenance Changes in water flow

The potential wider or secondary effects on protected or sensitive sub-littoral seabed due to removal or alteration of energy flow arising from devices and moorings or support structures.

Fish
Design feature

Design structures to minimise effect on turbulence structure.

Minimizes change in turbulence structure and hence potential interaction.

Can present financial, logistical, or design challenges to technology developer to alter design of device/moorings.

Aquamarine Power Ltd 2011, Davison and Mallows 2005, Tidal Energy Ltd 2008, Oyster 800 at EMEC, Strangford Lough - MCT (SeaGen), Ramsey Sound
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Fish
Elasmobranchs
Design feature

Use of 3-phase cables instead of DC cables.

Reduce the level of EMF to surrounding water column and therefore any potential effects.

Potential commercial and technical feasibility issues.

Some uncertainty as to the efficacy of this measure.

Tidal Energy Ltd 2008, Ramsey Sound
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Underwater noise

The potential effects from underwater noise generated during installation/ construction (excluding piling).

Fish
Mitigation

Limit vessel speed.

Reduces potential effects.

Relatively low-cost measure.

SAE Renewables 2011, Atlantis Resources Corporation at EMEC
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Habitat
Benthic invertebrates
Design feature

Bury or HDD cables where possible and viable.

Reduce the level of EMF to surrounding water column and therefore any potential effects.

Reduces 'snagging risk' for vessels.

May have an impact on surrounding benthic habitats and sensitive species.

Uncertainty around the need for and efficacy of this measure.

Can be very challenging or impossible at sites where seabed tends to be rocky.

Additional expense to the project.

...Read more

May have an impact on surrounding benthic habitats and sensitive species.

Uncertainty around the need for and efficacy of this measure.

Can be very challenging or impossible at sites where seabed tends to be rocky.

Additional expense to the project.

Reduced possibility for decommissioning.

Read less
Sustainable Energy Authority of Ireland (SEAI) 2011, Tidal Lagoon Power 2017, Federal Energy Regulatory Commission (FERC) 2020, Atlantic Marine Energy Test Site (AMETS), Swansea Bay Tidal Lagoon (SBTL), PacWave South Test Site
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Collision risk

The potential effects from airborne noise from support vessel activity.

Marine Mammals
Seals
Mitigation

Adherence to Scotish Marine Wildlife Watching Code (SMWWC).

European Marine Energy Centre (EMEC) 2014, Xodus Group 2019, European Marine Energy Centre (EMEC) 2020, SSE Renewables 2011, Magallanes Renovables 2020, Aquatera 2017, Laminaria 2018, Orbital Marine Power 2018, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Billia Croo Grid-Connected Wave Test Site, EMEC Scapa Flow Scale Wave Test Site, Westray South Tidal Project, Magallanes Renovables ATIR at EMEC, Tocardo InToTidal at EMEC, EMEC Billia Croo Grid-Connected Wave Test Site, Orbital Marine Power O2 at EMEC, Mocean Wave Energy Converter: Blue Horizon
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Marine Mammals
Cetaceans
Design feature

Minimise the number of mooring lines.

Reduce risk of entanglement.

Could be a costly measure for technology developers.

Tidal Operation & Maintenance Changes in water flow

The potential wider or secondary effects on protected or sensitive sub-littoral seabed due to removal or alteration of energy flow arising from devices and moorings or support structures.

Reptiles
Design feature

Design structures to minimise effect on turbulence structure.

Minimizeschange in turbulence structure and hence potential interaction.

Can present financial, logistical, or design challenges to technology developer to alter design of device/moorings

Aquamarine Power Ltd 2011, Davison and Mallows 2005, Oyster 800 at EMEC, Strangford Lough - MCT (SeaGen)
Wave, Tidal Installation, Decommissioning Changes in sediment dynamics

Sediment disturbance disrupting water clarity that results in smothering of fish spawning grounds.

Benthic
Mitigation

Best practice methodologies to reduce resuspension of sediment during cable burial or device foundation/mooring installation.

ScottishPower Renewables 2010, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, South West of England Regional Development Agency (SWDRA) 2006, Sustainable Energy Authority of Ireland (SEAI) 2011, Tidal Lagoon Power 2017, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, Sound of Islay Demonstration Tidal Array, Kyle Rhea Tidal Stream Array Project, Wave Hub, Atlantic Marine Energy Test Site (AMETS), Swansea Bay Tidal Lagoon (SBTL), Galway Bay Test Site, PacWave South Test Site
Wave, Tidal Operation & Maintenance Entrapment

Potential risk of entrapment within device chambers and mooring arrays.

Benthic
Mitigation

Regular ROV/drop down camera surveys to establish occurrence of entrapment

Early detection of entrapment.

Additional cost.

Foubister 2005, Orbital Marine Power 2010, Orbital Marine Power SR250 at EMEC
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Birds
Diving birds
Monitoring

Environmental monitoring to detect collision events.

Understand avoidance behavior, nature of interactions, and outcome of collision events.

Can be a high cost associated with measure.

Unclear how much monitoring will be required to fully understand this risk.

Technology is not advanced enough yet to do this efficiently.

Data mortgage (data generated more quickly than it can be analysed).

...Read more

Can be a high cost associated with measure.

Unclear how much monitoring will be required to fully understand this risk.

Technology is not advanced enough yet to do this efficiently.

Data mortgage (data generated more quickly than it can be analysed).

Power supply availability - hard-wired vs. battery; power is required for monitoring and power availability can present logistical, financial, and technical challenges.

Interaction between equipment - e.g., multibeam sonar/ADCP/echosounder; can be interaction between monitoring equipment which can present challenges in monitoring.

Certain equipment used such as PAM may actually effect behaviour themselves.

Read less
SAE Renewables 2011, Aquamarine Power Ltd 2011, Orbital Marine Power 2014, Minesto 2016, SSE Renewables 2011, Xodus Group 2012, McGrath 2013, GlaxoSmithKlineMontrose 2012, Atlantis Resources Corporation at EMEC, Oyster 800 at EMEC, Minesto Holyhead Deep - Non-grid connected DG500, Westray South Tidal Project, Costa Head Wave Farm, Fair Head Tidal Array, GSK Montrose Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Birds
Mitigation, Compliance

Adhere to appropriate measures when jettisoning ballast water.

Reduce/remove risk of transfer of non-native species.

Sustainable Energy Authority of Ireland (SEAI) 2011, Atlantic Marine Energy Test Site (AMETS)
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Birds
Diving birds
Mitigation

Reduce maximum blade tip speed.

Could reduce the likelihood/consequence of potential collision events.

Potential impacts on power production.

Control mechanism of turbine blade speed unclear.

May cause increased fatigue.

Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in lost fishing gear or other equipment trapped on infrastructure.

Fish
Elasmobranch, large fish
Monitoring

Ensure standard notifications of loss of fishing gear in region notified to operators. Reporting of entanglement events.

Good practice for emergency preparedness.

Chances of lost fishing gear being reported is reportedly low.

Federal Energy Regulatory Commission (FERC) 2020, PacWave South Test Site
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Changes in sediment dynamics

The potential wider or secondary effects (siltation changes or smothering) on protected or sensitive sub-littoral seabed due to scour or siltation around devices and associated moorings, support structures, and export cables.

Habitat
Benthic species
Design feature

Minimise the amount of structure on the seabed.

Minimizes the changes in sediment dynamics due to presence of structure on the seabed.

Can present financial, logistical, or design challenges to technology developer to alter design of device/moorings

OpenHydro and SSE Renewables 2013, Brims Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Habitat
Compliance

Compliance with all relevant guidance (including IMO guidelines) regarding ballast water management and transfer of non-native species.

Reduce/remove risk of transfer and settlement of non-native species.

McPherson 2015, MeyGen 2012, Xodus Group 2019, South West of England Regional Development Agency (SWDRA) 2006, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Magallanes Renovables 2020, Federal Energy Regulatory Commission (FERC) 2020, Orbital Marine Power 2018, Nova Innovation - Shetland Tidal Array, MeyGen Tidal Energy Project , EMEC Billia Croo Grid-Connected Wave Test Site, Wave Hub, Kyle Rhea Tidal Stream Array Project, Magallanes Renovables ATIR at EMEC, PacWave South Test Site, Orbital Marine Power O2 at EMEC
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
Mitigation

Minimise turbine standstill periods.

Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Marine Mammals
Monitoring

Monitoring and reporting of MNNS.

Reduces/removes risk of transfer of non-native species.

Orbital Marine Power 2018, Aquatera 2017, Orbital Marine Power O2 at EMEC, Tocardo InToTidal at EMEC
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Reptiles
Sea turtles
Monitoring

Fishing debris detected during routine inspections of mooring lines and cables will be removed.

Remove/reduce risk of entanglement.

Low cost measure, implemented as part of standard O&M procedures.

Regular monitoring will benefit system performance in addition to addressing environmental risks (e.g., early detection of damage or failures in the system).

Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for accidental or unplanned events which could lead to contamination of the marine environment.

Benthic
Compliance

Management: Establish and implement a Contamination Control Plan/Ship Oil Contamination Emergency Plans (SOPEPs).

Compliance with International Maritime Organization (IMO) and Maritime Coastguard Agency (MCA) codes for the prevention of contamination.

Reduces risk of any contamination/pollution event and ensures that contingency plans are in place. Demonstrates compliance with environmental management systems.

Low 2012, Foubister 2005, GlaxoSmithKlineMontrose 2012, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, RSK Group 2012, Magallanes Renovables 2020, Sustainable Energy Authority of Ireland (SEAI) 2011, Tidal Lagoon Power 2017, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, Aquamarine Power Ltd 2011, Atlantis Resources Corporation at EMEC, EMEC Fall of Warness Grid-Connected Tidal Test Site, GSK Montrose Tidal Array, Kyle Rhea Tidal Stream Array Project, West Orkney South Wave Energy Site, Magallanes Renovables ATIR at EMEC, Atlantic Marine Energy Test Site (AMETS), Swansea Bay Tidal Lagoon (SBTL), Galway Bay Test Site, PacWave South Test Site, Oyster 800 at EMEC
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Benthic
Mitigation

Source vessels locally.

Reduce/remove risk of transfer and settlement of non-native species.

MeyGen 2012, McPherson 2015, Magallanes Renovables 2020, Aquamarine Power Ltd 2011, MeyGen Tidal Energy Project , Nova Innovation - Shetland Tidal Array, Magallanes Renovables ATIR at EMEC, Oyster 800 at EMEC, Mocean Wave Energy Converter: Blue Horizon
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for accidental or unplanned events which could lead to contamination of the marine environment.

Birds
Mitigation, Compliance

Management: Establish and implement a Contamination Control Plan/Ship Oil Contamination Emergency Plans (SOPEPs).

Compliance with International Maritime Organization (IMO) and Maritime Coastguard Agency (MCA) codes for the prevention of contamination.

Reduces risk of any contamination/pollution event and ensures that contingency plans are in place.

Demonstrates compliance with environmental management systems.

Low 2012, MeyGen 2012, Orbital Marine Power 2010, GlaxoSmithKlineMontrose 2012, Foubister 2005, Davison and Mallows 2005, Xodus Group 2019, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Magallanes Renovables 2020, McGrath 2013, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, THETIS Energy 2009, Atlantis Resources Corporation at EMEC, MeyGen Tidal Energy Project , Pelamis Wave Power P2 Demonstration at EMEC, GSK Montrose Tidal Array, EMEC Fall of Warness Grid-Connected Tidal Test Site, Strangford Lough - MCT (SeaGen), EMEC Billia Croo Grid-Connected Wave Test Site, Kyle Rhea Tidal Stream Array Project, Magallanes Renovables ATIR at EMEC, Fair Head Tidal Array, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site, PacWave South Test Site, Torr Head Project
Wave, Tidal Installation Barrier to movement

Potential barrier to movement due to the physical presence of devices and associated moorings/support structures, cables and electrical equipment.

Fish
Design feature

Site selection to avoid sensitive routes/areas.

Minimizes risk of development acting as a barrier to movement by avoiding migratory routes or other important sites.

ScottishPower Renewables 2012, Ness of Duncansby Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Displacement

Potential displacement of essential activities due to the presence of devices and associated moorings/support structures.

Fish
Design feature

Array/ mooring configuration designed to avoid migratory routes or other important sites.

Minimizes risk of development creating displacement by avoiding migratory routes or other important sites.

May be inconsistent with optimal layout of the development for exploitation of the energy source.

Can be a costly measure when scaling up to larger arrays.

Aquamarine Power Ltd 2011, Davison and Mallows 2005, Oyster 800 at EMEC, Strangford Lough - MCT (SeaGen)
Wave, Tidal Installation, Decommissioning Habitat Loss

Direct loss of protected or sensitive sub-littoral seabed communities due to the presence of devices and associated moorings or support structures on the seabed.

Fish
Demersal fish
Design feature

Site selection to avoid sensitive or protected sub-littoral seabed communities.

Could reduce/remove effects on sensitive habitats.

ScottishPower Renewables 2012, Ness of Duncansby Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

Potential for oil spill incident resulting from the influence of unfavourable weather conditions.

Habitat
Mitigation

Vessel activities to occur in suitable weather conditions.

Reduces the chance for oil spill to the environment.

MeyGen 2012, The Marine Institute 2016, ScottishPower Renewables 2012, MeyGen Tidal Energy Project , Galway Bay Test Site, Pelamis Wave Power P2 Demonstration at EMEC
Wave, Tidal Installation, Decommissioning Changes in sediment dynamics

Sediment disturbance disrupting water clarity that results in smothering of fish spawning grounds.

Marine Mammals
Mitigation

Best practice methodologies to reduce resuspension of sediment during cable burial or device foundation/mooring installation.

Craig 2008, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, OpenHydro Alderney, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site, PacWave South Test Site
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Displacement

Potential displacement of essential activities due to the presence of devices and associated moorings/support structures.

Marine Mammals
Mitigation

Timing of installation and decommissioning & marine operations to avoid times of particular sensitivity (e.g., breeding).

Minimizes risk of development causing displacement by avoiding works during sensitive times.

Can be disruptive and hence costly to developer.

OpenHydro and SSE Renewables 2013, Aquatera Ltd 2011, Foubister 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, SSE Renewables 2011, ScottishPower Renewables 2012, McGrath 2013, Orbital Marine Power 2014, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, THETIS Energy 2009, ScottishPower Renewables 2012, Brims Tidal Array, Wello Penguin at EMEC, EMEC Fall of Warness Grid-Connected Tidal Test Site, Kyle Rhea Tidal Stream Array Project, Westray South Tidal Project, Fair Head Tidal Array, Galway Bay Test Site, PacWave South Test Site, Torr Head Project, Ness of Duncansby Tidal Array
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Vessel disturbance

Potential for disturbance from project vessels.

Marine Mammals
seals
Mitigation

Employ an MMO during periods when noisy operations are likely to cause disturbance (e.g., all operations using a DP vessel).

SAE Renewables 2011, Orbital Marine Power 2010, Minesto 2016, Foubister 2005, European Marine Energy Centre (EMEC) 2014, Xodus Group 2019, Magallanes Renovables 2020, MeyGen 2012, DP Energy Ltd. 2013, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, THETIS Energy 2009, Davison and Mallows 2005, Atlantis Resources Corporation at EMEC, Pelamis Wave Power P2 Demonstration at EMEC, Minesto Holyhead Deep - Non-grid connected DG500, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Billia Croo Grid-Connected Wave Test Site, Magallanes Renovables ATIR at EMEC, MeyGen Tidal Energy Project , West Islay Tidal Project Energy Park, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site, PacWave South Test Site, Torr Head Project, Strangford Lough - MCT (SeaGen)
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Reptiles
Mitigation

Source vessels locally.

Reduce/remove risk of transfer and settlement of non-native species.

Mocean Wave Energy Converter: Blue Horizon
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Limit cable voltage.

MeyGen 2012, MeyGen Tidal Energy Project
Wave, Tidal Installation, Decommissioning Changes in sediment dynamics

Reduced visibility impacting prey detection and obstruction avoidance.

Birds
Mitigation

Best practice methodologies to reduce resuspension of sediment during cable burial or device foundation/mooring installation.

Foubister 2005, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, EMEC Fall of Warness Grid-Connected Tidal Test Site, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site, PacWave South Test Site
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Birds
Diving birds
Monitoring

Install tension sensors on mooring lines.

Informs of problem with mooring lines allowing rectification.

Cost per unit.

Additional cost and control system integration requirement.

Load from entangled animal is likely to be smaller than the device loading on the moorings.

Uncertainty of the efficacy of this measure.

Laminaria 2018, EMEC Billia Croo Grid-Connected Wave Test Site
Tidal Operation & Maintenance Changes in water flow

Modifications to prey distribution and abundance (to include for other receptors) resulting in changes to foraging behaviour.

Fish
Design feature

Design structures to minimise effect on turbulence structure.

Minimizes change in turbulence structure and hence potential interaction.

Can present financial, logistical, or design challenges to technology developer to alter design of device/moorings.

Aquamarine Power Ltd 2011, Davison and Mallows 2005, Tidal Energy Ltd 2008, Oyster 800 at EMEC, Strangford Lough - MCT (SeaGen), Ramsey Sound
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Fish
Migratory fish
Design feature

Bundle cables together to reduce field vectors.

Reduce the level of EMF to surrounding water column and therefore any potential effects.

Less redundancy in system.

Potential commercial and technical feasibility issues.

Greater costs associated with not laying direct cable paths.

MeyGen 2012, MeyGen Tidal Energy Project
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Underwater noise

The potential effects from airborne noise from support vessel activity.

Fish
Mitigation

Adherence to Scotish Marine Wildlife Watching Code (SMWWC).

European Marine Energy Centre (EMEC) 2014, Magallanes Renovables 2020, Xodus Group 2019, European Marine Energy Centre (EMEC) 2020, Aquatera 2017, Laminaria 2018, Orbital Marine Power 2018, EMEC Fall of Warness Grid-Connected Tidal Test Site, Magallanes Renovables ATIR at EMEC, EMEC Billia Croo Grid-Connected Wave Test Site, EMEC Scapa Flow Scale Wave Test Site, Tocardo InToTidal at EMEC, Orbital Marine Power O2 at EMEC, Mocean Wave Energy Converter: Blue Horizon
Wave, Tidal Operation & Maintenance Habitat Creation

The introduction of infrastructure and artificial substrates will provide habitat and artificial refuges.

Habitat
Monitoring

Monitor near-field behaviours.

Reduces scientific uncertainty around collision risk, displacement, and other impacts.

Increased value/fecundity of commercially important species.

Can be expensive and difficult to deliver in practice.

May require additional licensing (e.g., echosounders).

Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
Mitigation

Install propeller guards.

McGrath 2013, Fair Head Tidal Array
Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Marine Mammals
Cetaceans
Mitigation

Install strain gauges on the device

Alerts the opertaor in the event of an entanglement event.

Magallanes Renovables 2020, Magallanes Renovables ATIR at EMEC
Tidal Operation & Maintenance Changes in water flow

The potential wider or secondary effects on protected or sensitive sub-littoral seabed due to removal or alteration of energy flow arising from devices and moorings or support structures.

Reptiles
Monitoring

Modelling to predict the interaction between changes in tidal flow, flux, and turbulence structure and animals.

Reduces scientific uncertainty so appropriate management measures can be employed

Limited management measures available to minimise interaction despite modelling to fully predict interaction

Wave, Tidal Installation, Operation & Maintenance, Decommissioning Changes in sediment dynamics

The potential wider or secondary effects (siltation changes or smothering) on protected or sensitive sub-littoral seabed due to scour or siltation around devices and associated moorings, support structures, and export cables.

Benthic
Design feature

Minimize the amount of structure on the seabed.

Minimises the changes in sediment dynamics due to presence of structure on the seabed.

Can present financial/ logistical/ design challenges to technology developer to alter design of device/moorings.

OpenHydro and SSE Renewables 2013, Brims Tidal Array
Wave, Tidal Operation & Maintenance Habitat Creation

The introduction of infrastructure and artificial substrates may generate additional habitat diversity.

Benthic
Benthic species
Monitoring

Structure colonization and biofouling surveys.

Informs understanding of potential for increased prey availability and ecological diversity.

Cost associated with monitoring.

Magallanes Renovables 2020, Orbital Marine Power 2018, Magallanes Renovables ATIR at EMEC, Orbital Marine Power O2 at EMEC
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Birds
Diving birds
Monitoring

Environmental monitoring to better understand near-field behaviour and avoidance.

Telp reduce scientific uncertainty.

Can be a high cost associated with this.

Unclear how much monitoring will be required to fully understand this risk.

Technology is not advanced enough yet to do this efficiently.

Data mortgage (data generated more quickly than it can be analysed).

...Read more

Can be a high cost associated with this.

Unclear how much monitoring will be required to fully understand this risk.

Technology is not advanced enough yet to do this efficiently.

Data mortgage (data generated more quickly than it can be analysed).

Power supply availability - hard-wired vs. battery; power is required for monitoring and power availability can present logistical, financial, and technical challenges.

Interaction between equipment - e.g., multibeam sonar/ADCP/echosounder; there can be interaction between monitoring equipment which can present challenges in monitoring.

Certain equipment used such as PAM may actually effect behaviour themselves.

Read less
Aquamarine Power Ltd 2011, OpenHydro and SSE Renewables 2013, Minesto 2016, SSE Renewables 2011, Xodus Group 2012, GlaxoSmithKlineMontrose 2012, Orbital Marine Power 2018, Oyster 800 at EMEC, Brims Tidal Array, Minesto Holyhead Deep - Non-grid connected DG500, Westray South Tidal Project, Costa Head Wave Farm, GSK Montrose Tidal Array, Orbital Marine Power O2 at EMEC
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Birds
Mitigation

Source vessels locally.

Reduce/remove risk of transfer and settlement of non-native species.

McPherson 2015, Nova Innovation - Shetland Tidal Array, Mocean Wave Energy Converter: Blue Horizon
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Birds
Diving birds
Mitigation

Design proportion of swept area to structure area to minimise collision risk.

Could reduce the likelihood/consequence of potential collision events.

Can be a high cost associated with this.

Can present financial, logistical, or design challenges to technology developer to alter design of device.

Wave, Tidal Operation & Maintenance Entanglement

Potential for marine animals to become entangled in device mooring lines and cables.

Fish
Elasmobranch, large fish
Design feature, Monitoring

Routine inspections of mooring lines. Implement features into existing control systems to detect entanglement events.

Remove/reduce risk of entanglement.

Likely to be required as part of the technical monitoring of the device and therefore not an additional cost

Could be a costly measure for technology developers if not required as part of technical monitoring of device.

Argyll Tidal Limited 2013, European Marine Energy Centre (EMEC) 2014, Xodus Group 2019, Federal Energy Regulatory Commission (FERC) 2020, Argyll Tidal Demonstrator Project, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Billia Croo Grid-Connected Wave Test Site, PacWave South Test Site
Tidal Operation & Maintenance Changes in water flow

The potential wider or secondary effects (siltation changes or smothering) on protected or sensitive littoral habitat due to changes in tidal flow around devices and associated moorings, support structures, or landfall cables.

Habitat
Benthic invertebrates
Monitoring

Pre and post installation monitoring of sensitive benthic communities, based on visual surveys.

Reduce scientific uncertainty.

Interpretation of data for statistical purposes may not have power to detect change generated by impact.

May require correlation with detailed Computational Fluid Dynamics studies and physical flow measurements.

Orbital Marine Power 2014, European Marine Energy Centre (EMEC) 2011, Davison and Mallows 2005, ScottishPower Renewables 2010, The Marine Institute 2016, Orbital Marine Power 2018, EMEC Shapinsay Sound Scale Tidal Test Site, Strangford Lough - MCT (SeaGen), Sound of Islay Demonstration Tidal Array, Galway Bay Test Site, Orbital Marine Power O2 at EMEC
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Marine Non-Native Species (MNNS)

Potential for introduction of MNNS which can have an adverse impact on the native species at the site.

Habitat
Mitigation

Establish and implement a Biofouling Management Plan.

Reduce/remove risk of transfer of non-native species.

Lack of industry specific guidance.

European Marine Energy Centre (EMEC) 2014, Xodus Group 2019, Orbital Marine Power 2018, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Billia Croo Grid-Connected Wave Test Site, Orbital Marine Power O2 at EMEC