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 1 - 100 of 339 management measures
Technology Project Phase Stressor Receptor Management Measure Advantages Challenges Project Documents
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 - Phase I, HS1000 at EMEC, Strangford Lough - MCT (SeaGen), Galway Bay Test Site, Torr Head Project
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Benthic
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 cost 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 cost to the project.

Reduced possibility of decommissioning.

Read less
Sustainable Energy Authority of Ireland (SEAI) 2011, Federal Energy Regulatory Commission (FERC) 2020, Atlantic Marine Energy Test Site (AMETS), PacWave South 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.

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
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.

Birds
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 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 - Phase I, 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 Operation & Maintenance Habitat Creation

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

Birds
Monitoring

Monitor near-field behaviors.

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

Increased value/fecundity of commercially important species.

Informs understanding of potential positive impacts from colonization and use of the project infrastructure.

This type of monitoring can be expensive and difficult to deliver in practice.

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

MeyGen 2012, Tidal Lagoon Power 2017, MeyGen Tidal Energy Project - Phase I, Swansea Bay Tidal Lagoon (SBTL)
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 - Phase I
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

Site selection.

Minimizes significance of interaction.

ScottishPower Renewables 2012, Ness of Duncansby Tidal Array
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 EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Fish
Migratory fish
Design feature

Micrositing of offshore infrastructure to avoid sensitive habitats and minimise footprint.

Could reduce/remove effects on sensitive habitats.

Relatively low cost measure.

DP Energy Ltd. 2013, ScottishPower Renewables 2012, Laminaria 2018, Tidal Lagoon Power 2017, The Marine Institute 2016, West Islay Tidal Project Energy Park, EMEC Billia Croo Grid-Connected Wave Test Site, Swansea Bay Tidal Lagoon (SBTL), Galway Bay Test Site
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 Barrier to movement

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

Habitat
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, OpenHydro and SSE Group 2013, Ness of Duncansby Tidal Array, Brims Tidal Array
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 - Phase I, 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 Installation, Operation & Maintenance Habitat Loss

Direct loss of protected or sensitive intertidal communities from changes in hydrodynamics due to nearshore WECs.

Habitat
Intertidal ecology
Design feature

Micrositing of nearshore WECs to minimise the impact on sensitive habitats and species.

Foubister 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, South West of England Regional Development Agency (SWDRA) 2006, SSE Group 2011, ScottishPower Renewables 2012, MeyGen 2012, Laminaria 2018, The Marine Institute 2016, EMEC Fall of Warness Grid-Connected Tidal Test Site, Kyle Rhea Tidal Stream Array Project, Wave Hub, Westray South Tidal Project, MeyGen Tidal Energy Project - Phase I, EMEC Billia Croo Grid-Connected Wave Test Site, Galway Bay 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
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
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 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 gathered 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 gathered 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
SIMEC Atlantis Energy Ltd 2011, Aquamarine Power Ltd 2011, GlaxoSmithKlineMontrose 2012, Orbital Marine Power 2014, ScottishPower Renewables 2010, Davison and Mallows 2005, McGrath 2013, Tidal Lagoon Power 2017, Orbital Marine Power 2018, Atlantis Resources Corporation at EMEC, Oyster 800 at EMEC, GSK Montrose Tidal Array, Sound of Islay Demonstration Tidal Array, Strangford Lough - MCT (SeaGen), Fair Head Tidal Array, Swansea Bay Tidal Lagoon (SBTL)
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).

SIMEC Atlantis Energy Ltd 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 - Phase I, 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 Operation & Maintenance Habitat Creation

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

Marine Mammals
Monitoring

Monitor near-field behaviours.

Informs understanding of potential positive impacts from colonization and use of the project infrastructure.

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).

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
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

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

Reptiles
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.)

Foubister 2005, MeyGen 2012, Xodus AURORA 2010, The Marine Institute 2016, THETIS Energy 2009, EMEC Fall of Warness Grid-Connected Tidal Test Site, MeyGen Tidal Energy Project - Phase I, HS1000 at EMEC, 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.

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 Installation Barrier to movement

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

Benthic
Design feature

Site selection to avoid sensitive routes/areas.

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

Argyll Tidal Limited 2013, OpenHydro and SSE Group 2013, Argyll Tidal Demonstrator Project, Brims Tidal Array
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 Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Lay cables in natural crevices.

MeyGen 2012, MeyGen Tidal Energy Project - Phase I
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)
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.

Birds
Design feature

Design structures to minimise effect on turbulence structure.

Minimises 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 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 Operation & Maintenance Habitat Creation

The introduction of infrastructure and artificial substrates will provide potential roosting habitat.

Birds
Roosting birds
Monitoring

Monitor use of device as a roosting platform.

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

Data mortgage (concept of generating data more quickly than it can be analysed).

Could be expensive to monitor.

DP Energy Ltd. 2013, Orbital Marine Power 2018, West Islay Tidal Project Energy Park
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.

SIMEC Atlantis Energy Ltd 2011, OpenHydro and SSE Group 2013, Atlantis Resources Corporation at EMEC, Brims Tidal Array
Tidal Operation & Maintenance Changes in water flow

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

Fish
Design feature

Site selection.

Minimizes significance of interaction.

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
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 Group 2013, Aquatera Ltd 2011, Foubister 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, SSE Group 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 Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Fish
Demersal fish
Design feature

Install cable protection/armour.

Higher levels of insulation reduces the level of EMF to surrounding water column and therefore any potential effects.

DP Energy Ltd. 2013, Foubister 2005, Federal Energy Regulatory Commission (FERC) 2020, West Islay Tidal Project Energy Park, EMEC Fall of Warness Grid-Connected Tidal Test Site, PacWave South Test Site
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 Barrier to movement

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

Habitat
Design feature

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

Minimizes 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, Davison and Mallows 2005, Oyster 800 at EMEC, Strangford Lough - MCT (SeaGen)
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 Habitat Loss

Loss of intertidal habitat from trenching for cable landfall.

Habitat
Intertidal ecology
Design feature

Pre-construction cable route surveys to avoid sensitive habitats.

Orbital Marine Power 2014, OpenHydro and SSE Group 2013, ScottishPower Renewables 2012, Brims Tidal Array, Pelamis Wave Power P2 Demonstration at EMEC
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
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
Mitigation

Implement a 'soft start'/cut in speed management approach during cut-in at sensitive sites, i.e. those where the potential for collisions is high.

Soft start could reduce risk by allowing animals time to move away from the turbine.

Cut in speed management could be used to reduce risk during periods of known higher activity in sensitive species.

Low cost option, adopted for other activities (e.g., piling).

Unclear if this offers additional mitigation as many devices power up gradually anyway.

Implementation of this measure could result in a loss of revenue for the developer.

Xodus Group 2019, EMEC Billia Croo Grid-Connected Wave 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 Operation & Maintenance Lighting

Potential for lighting to adversely affect nocturnal and migratory species.

Marine Mammals
Design feature

Consider type, color, and use of lighting during design and consultation with navigational stakeholders.

May reduce impacts on sensitive species if they are known to use or migrate near to the project site.

Navigational safety and interests need to be considered and make take precedence.

DP Energy Ltd. 2013, European Marine Energy Centre (EMEC) 2014, Tidal Lagoon Power 2017, West Islay Tidal Project Energy Park, EMEC Fall of Warness Grid-Connected Tidal Test Site, Swansea Bay Tidal Lagoon (SBTL)
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, SIMEC Atlantis Energy Ltd 2011, Oyster 800 at EMEC, Atlantis Resources Corporation at EMEC
Wave, Tidal Installation, Operation & Maintenance, Decommissioning Contamination

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

Reptiles
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.

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 Installation Barrier to movement

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

Benthic
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, 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
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, 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 EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Micrositing of offshore infrastructure to avoid sensitive habitats and minimise footprint.

Could reduce/remove effects on sensitive habitats.

Can often be done with little additional cost

ScottishPower Renewables 2012, Laminaria 2018, The Marine Institute 2016, EMEC Billia Croo Grid-Connected Wave Test Site, 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.

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 - Phase I, Nova Innovation - Shetland Tidal Array, Magallanes Renovables ATIR at EMEC, Oyster 800 at EMEC, Mocean Wave Energy Converter: Blue Horizon
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.

Birds
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 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 - Phase I, 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 Operation & Maintenance Lighting

Potential for lighting to adversely affect nocturnal and migratory species.

Birds
Seabirds
Design feature

Consider type, color, and use of lighting during design and consultation with navigational stakeholders.

A targeted lighting plan may have the potential to reduce impacts on sensitive species.

Navigational safety are a consideration and may take priority over implementation of ecological aspects.

Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Kyle Rhea Tidal Stream Array 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
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Fish
Monitoring

Environmental monitoring to detect collision events.

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

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 gathered 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 gathered 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
SIMEC Atlantis Energy Ltd 2011, GlaxoSmithKlineMontrose 2012, Orbital Marine Power 2014, Atlantis Resources Corporation 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.

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 Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Fish
Demersal fish
Design feature

Limit cable voltage.

MeyGen 2012, MeyGen Tidal Energy Project - Phase I
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 Barrier to movement

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

Habitat
Mitigation

Adherence to vessel management plan.

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

OpenHydro and SSE Group 2013, Aquatera 2017, ScottishPower Renewables 2010, Brims Tidal Array, Tocardo InToTidal at EMEC, Sound of Islay Demonstration 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 - Phase I, Galway Bay Test Site, Pelamis Wave Power P2 Demonstration at EMEC
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

Micrositing of offshore infrastructure to avoid sensitive habitats and minimise footprint.

Could reduce/remove effects on sensitive habitats.

Low cost measure at single device or small-scale array.

MeyGen 2012, ScottishPower Renewables 2012, ScottishPower Renewables 2010, Davison and Mallows 2005, SSE Group 2011, Laminaria 2018, Tidal Lagoon Power 2017, Sustainable Energy Authority of Ireland (SEAI) 2011, MeyGen Tidal Energy Project - Phase I, Ness of Duncansby Tidal Array, Sound of Islay Demonstration Tidal Array, Strangford Lough - MCT (SeaGen), Westray South Tidal Project, EMEC Billia Croo Grid-Connected Wave Test Site, Swansea Bay Tidal Lagoon (SBTL), Atlantic Marine Energy Test Site (AMETS)
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
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
Monitoring

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

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 gathered 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 gathered 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
GlaxoSmithKlineMontrose 2012, Minesto 2016, Davison and Mallows 2005, Xodus Group 2019, McGrath 2013, MeyGen 2012, Orbital Marine Power 2018, GSK Montrose Tidal Array, Minesto Holyhead Deep - Non-grid connected DG500, Strangford Lough - MCT (SeaGen), EMEC Billia Croo Grid-Connected Wave Test Site, Fair Head Tidal Array, MeyGen Tidal Energy Project - Phase I
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 Group 2013, Aquatera Ltd 2011, Foubister 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, SSE Group 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 Operation & Maintenance Lighting

Potential for light from installation vessels to adversely affect nocturnal and migratory species.

Marine Mammals
Monitoring

Monitoring effects on animals.

Reduce scientific uncertainty.

Can be difficult to detect change as a result of interaction as opposed to natural variability.

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).

SIMEC Atlantis Energy Ltd 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 - Phase I, 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 Contamination

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

Reptiles
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, MeyGen 2012, Xodus AURORA 2010, Foubister 2005, Davison and Mallows 2005, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, The Marine Institute 2016, Federal Energy Regulatory Commission (FERC) 2020, EMEC Fall of Warness Grid-Connected Tidal Test Site, MeyGen Tidal Energy Project - Phase I, HS1000 at EMEC, Strangford Lough - MCT (SeaGen), Kyle Rhea Tidal Stream Array Project, Galway Bay Test Site, PacWave South 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.

Reptiles
Mitigation

Source vessels locally.

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

Mocean Wave Energy Converter: Blue Horizon
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.

Benthic
Mitigation

Adherence to vessel management plan.

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

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

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

Benthic
Mitigation

Vessel activities to occur in suitable weather conditions.

Reduces the chance of oil spill to the environment.

MeyGen 2012, Aquamarine Power Ltd 2011, ScottishPower Renewables 2012, MeyGen Tidal Energy Project - Phase I, Oyster 800 at EMEC, Pelamis Wave Power P2 Demonstration at EMEC
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Maximise length of any drilled boreholes.

MeyGen 2012, MeyGen Tidal Energy Project - Phase I
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

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.

MeyGen 2012, McPherson 2015, OpenHydro and SSE Group 2013, European Marine Energy Centre (EMEC) 2014, Xodus Group 2019, Magallanes Renovables 2020, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, SSE Group 2011, Tidal Lagoon Power 2017, Federal Energy Regulatory Commission (FERC) 2020, MeyGen Tidal Energy Project - Phase I, Nova Innovation - Shetland Tidal Array, Brims Tidal Array, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Billia Croo Grid-Connected Wave Test Site, Magallanes Renovables ATIR at EMEC, Kyle Rhea Tidal Stream Array Project, Westray South Tidal Project, Swansea Bay Tidal Lagoon (SBTL), PacWave South 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.

Birds
Design feature

Site selection.

Minimizes significance of interaction.

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

Potential for oil/hydraulic spill incident resulting from the maintenance activities.

Fish
Mitigation

All maintenance activities involving oil/hydraulic fluid treatments will be carried out on-shore.

Reduces the chance for oil spill to the environment.

Foubister 2005, EMEC Fall of Warness Grid-Connected Tidal Test Site
Wave, Tidal Installation Lighting

Potential for light from installation vessels to adversely affect nocturnal and migratory species.

Birds
Seabirds
Mitigation

Limit lighting on installation vessels to that safe for navigational purposes only.

Reduce impact on sensitive species.

A lot of the light on navigational vessels is superflous so would not detract from their safe operation.

Xodus Group 2019, EMEC Billia Croo Grid-Connected Wave 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.

Fish
Design feature

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

Minimizes 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, Davison and Mallows 2005, Oyster 800 at EMEC, Strangford Lough - MCT (SeaGen)
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Fish
Elasmobranch
Mitigation

Implement a 'soft start'/cut in speed management approach at sensitive sites, i.e. those where the potential for collisions is high.

Soft start could reduce risk by allowing animals time to move away from the turbine.

Cut in speed management could be used to reduce risk during periods of known higher activity in sensitive species.

Low cost option, adopted for other activities (e.g., piling).

Unclear if this offers additional mitigation as many devices power up gradually anyway.

Implementation of this measure could result in a loss of revenue for the developer.

MeyGen 2012, European Marine Energy Centre (EMEC) 2014, SIMEC Atlantis Energy Ltd 2011, Tidal Lagoon Power 2017, MeyGen Tidal Energy Project - Phase I, EMEC Fall of Warness Grid-Connected Tidal Test Site, Atlantis Resources Corporation at EMEC, Swansea Bay Tidal Lagoon (SBTL)
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from subsea cables on sensitive species.

Fish
Migratory fish, elasmobranchs
Design feature

Install cable protection, armor, rock placement, or other cable protection.

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

Reduces 'snagging risk' for vessels.

Creation of artificial habitat.

May have an impact on surrounding benthic habitats and sensitive species

Creation of artificial habitat may cause aggregation effect causing greater impact of EMF.

Increased cost to project.

Reduced possibilities for decommissioning in future.

Orbital Marine Power 2014, Foubister 2005, McGrath 2013, Federal Energy Regulatory Commission (FERC) 2020, EMEC Fall of Warness Grid-Connected Tidal Test Site, Fair Head Tidal Array, PacWave South 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

Maintain taut mooring lines.

Remove/reduce risk of entanglement.

Regular inspections can provide insight to interaction with marine animals.

Mooring design driven by technical and commercial consideration.

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

Aquatera Ltd 2011, Laminaria 2018, Federal Energy Regulatory Commission (FERC) 2020, Wello Penguin at EMEC, EMEC Billia Croo Grid-Connected Wave Test Site, PacWave South Test Site
Wave, Tidal Operation & Maintenance Lighting

Potential for lighting to adversely affect nocturnal and migratory species.

Fish
Design feature

Consider type, colour and use of lighting during design and consultation with navigational stakeholders.

Could redcue impacts on sensitive species if they are known to use or migrate near to the project site.

Navigational saftey need to be considered at all times and may take precedent over ecological needs.

DP Energy Ltd. 2013, European Marine Energy Centre (EMEC) 2014, Tidal Lagoon Power 2017, West Islay Tidal Project Energy Park, EMEC Fall of Warness Grid-Connected Tidal Test Site, Swansea Bay Tidal Lagoon (SBTL)
Wave, Tidal Installation, Decommissioning Changes in sediment dynamics

Reduced visibility impacting prey detection and obstruction avoidance.

Habitat
Mitigation

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

Orbital Marine Power 2014, Foubister 2005, ScottishPower Renewables 2010, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, EMEC Fall of Warness Grid-Connected Tidal Test Site, Sound of Islay Demonstration Tidal Array, Kyle Rhea Tidal Stream Array Project, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site
Wave, Tidal Operation & Maintenance Contamination

Potential for oil/hydraulic spill incident resulting from the maintenance activities.

Habitat
Mitigation

All maintenance activities involving oil/hydraulic fluid treatments will be carried out on-shore.

Reduces the chance for oil spill to the environment.

Foubister 2005, EMEC Fall of Warness Grid-Connected Tidal Test Site
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

Minimise footprint of anchors/foundations.

Could reduce effects on sensitive habitats.

May impact technical considerations.

Low 2012, OpenHydro and SSE Group 2013, SSE Group 2011, Brims Tidal Array, Westray South Tidal Project
Tidal Operation & Maintenance Changes in water flow

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

Marine Mammals
Monitoring

Observational surveys (including remote sensing) of bird and marine mammals (prey availability linked to benthic community).

Reduces scientific uncertainty.

Statistical power of studies can be low. Can be difficult to distinguish between natural variation and direct effects of energy removal from the system.

Monitoring may be expensive.

Aquamarine Power Ltd 2011, GlaxoSmithKlineMontrose 2012, Orbital Marine Power 2014, Tidal Energy Ltd 2008, Xodus AURORA 2010, European Marine Energy Centre (EMEC) 2011, Davison and Mallows 2005, McGrath 2013, Xodus Group 2012, Orbital Marine Power 2018, Oyster 800 at EMEC, GSK Montrose Tidal Array, Ramsey Sound, HS1000 at EMEC, EMEC Shapinsay Sound Scale Tidal Test Site, Strangford Lough - MCT (SeaGen), Fair Head Tidal Array
Tidal Operation & Maintenance Collision risk

Potential for collision with turbine blades.

Marine Mammals
Mitigation

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

Possible that this will aid detection of subsea structures and help reduce risk.

Can be captured in early project design for a small one-off cost.

Could result in 'attraction', increasing risk of collision.

Uncertainty around how animals use visual cues, further research needed. Other sensory organs are often more important for seals.

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

Xodus Group 2019, EMEC Billia Croo Grid-Connected Wave 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
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 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

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
Wave, Tidal Decommissioning Vessel disturbance

Potential for disturbance from project vessels.

Marine Mammals
Cetaceans, seals
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 - Phase I
Wave, Tidal Operation & Maintenance Displacement

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

Reptiles
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.

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
Monitoring

Monitoring and reporting of MNNS.

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

Wave, Tidal Operation & Maintenance 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
Benthic invertebrates, demersal fish
Monitoring

Periodic visual monitoring through the use of divers or drop down video, static cameras / remote sensing techniques, benthic grab surveys, geophysical survey to identify scour pits, turbidity measurements.

Generation of data to quantify level and spatial extent of effect.

Technical and health and safety risks associated with periodic monitoring operation in close vicinity of infrastructure.

May require power shut down measure.

Subsea static monitoring options require O&M which may have time and cost implications.

Tidal Energy Ltd 2008, OpenHydro and SSE Group 2013, Foubister 2005, European Marine Energy Centre (EMEC) 2011, ScottishPower Renewables 2010, Davison and Mallows 2005, SSE Group 2011, Federal Energy Regulatory Commission (FERC) 2020, Xodus Group 2012, Ramsey Sound, Brims Tidal Array, EMEC Fall of Warness Grid-Connected Tidal Test Site, EMEC Shapinsay Sound Scale Tidal Test Site, Sound of Islay Demonstration Tidal Array, Strangford Lough - MCT (SeaGen), Westray South Tidal Project, PacWave South Test Site
Wave, Tidal Operation & Maintenance Contamination

Potential for oil/hydraulic spill incident resulting from the maintenance activities.

Benthic
Mitigation

All maintenance activities involving oil/hydraulic fluid treatments will be carried out on-shore.

Reduces the chance of oil spill to the environment.

Foubister 2005, EMEC Fall of Warness Grid-Connected Tidal Test Site
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Benthic
Benthic invertebrates
Design feature

Strategic use of rock placement/other cable protection.

Orbital Marine Power 2010, MeyGen 2012, DP Energy Ltd. 2017, ScottishPower Renewables 2010, DP Energy Ltd. 2013, Westray South Tidal Project, MeyGen Tidal Energy Project - Phase I, Sound of Islay Demonstration Tidal Array, West Islay Tidal Project Energy Park
Wave, Tidal Installation Marine Non-Native Species (MNNS)

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

Benthic
Design feature

Avoid the introduction of hard bottom substrate into a soft bottom habitat.

Ensures the efficient recovery of species native to the surrounding habitat.

May have technical implications.

Minesto 2016, Federal Energy Regulatory Commission (FERC) 2020, Minesto Holyhead Deep - Non-grid connected DG500, 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

Design structures to minimize 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 Displacement

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

Birds
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.

Argyll Tidal Limited 2013, Orbital Marine Power 2014, ScottishPower Renewables 2012, Argyll Tidal Demonstrator Project, Ness of Duncansby Tidal Array
Wave, Tidal Operation & Maintenance Lighting

Potential for light from installation vessels to adversely affect nocturnal and migratory species.

Birds
Seabirds
Monitoring

Monitoring effects on animals.

Reduce scientific uncertainty.

Can be difficult to detect change as a result of interaction as opposed to natural variability.

Xodus Group 2019, EMEC Billia Croo Grid-Connected Wave 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.

Fish
Mitigation

Adherence to vessel management plan.

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

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

Potential for collision with turbine blades.

Fish
Monitoring

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

Could reduce potential effects on sensitive species during sensitive periods.

Help 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 gathered 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 gathered 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
Xodus Group 2019, Magallanes Renovables 2020, EMEC Billia Croo Grid-Connected Wave Test Site, Magallanes Renovables ATIR at EMEC
Wave, Tidal Operation & Maintenance EMF

Impacts of electromagnetic fields from landfall cables on sensitive species.

Fish
Demersal fish
Design feature

Use of 3-phase cables instead of DC cables.

Tidal Energy Ltd 2008, Ramsey Sound
Wave, Tidal Operation & Maintenance Entanglement

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

Fish
Elasmobranch, large fish
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
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.

Fish
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, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Federal Energy Regulatory Commission (FERC) 2020, Nova Innovation - Shetland Tidal Array, MeyGen Tidal Energy Project - Phase I, Kyle Rhea Tidal Stream Array Project, PacWave South Test Site
Wave, Tidal Installation, Decommissioning Changes in sediment dynamics

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

Habitat
Mitigation

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

Orbital Marine Power 2014, ScottishPower Renewables 2010, Royal Haskoning and Sea Generation (Kyle Rhea) Ltd. 2013, Sustainable Energy Authority of Ireland (SEAI) 2011, The Marine Institute 2016, Sound of Islay Demonstration Tidal Array, Kyle Rhea Tidal Stream Array Project, Atlantic Marine Energy Test Site (AMETS), Galway Bay Test Site