Sectoral marine plan: appropriate assessment

Physical Loss/Gain of habitat

(loss of habitat in development footprint)

PLG

Loss of coastal and offshore habitat due to installation of devices, cables and cable armouring from the installation, operation and decommissioning of these structures.

Loss of coastal/offshore seabed within development footprint

Physical Loss/Gain of habitat

(direct change to habitat around the development footprint)

PLG

Loss of foraging areas from reduction in coastal and offshore habitat due to installation of devices and cable armouring both at the development footprint and outside these areas from associated scour and indirectly from changes to the hydrodynamic regime, as well as from chains anchoring devices disturbing seabed habitat during operation.

Loss of coastal/offshore foraging areas within development footprint

Physical Loss/Gain of habitat

(direct change to habitat around the development footprint)

PLG

Presence of structures on or above seabed for the duration of the project resulting in changes to prey and species behaviour (e.g. acting as FAD (Fish Aggregating Device), artificial reef or bird roost).

Loss or gain of habitat from introduced structures causing species change

Physical Damage to habitat

(indirect and temporary damage to marine habitat)

PD

Changes to coastal and offshore habitat as result of damage from baseline surveys (e.g. boreholes/trawls); from equipment use causing abrasion, damage or smothering during installation and from maintenance and removal of cables/devices (e.g. jack-up legs, vessels, anchors, mooring chain).

Damage to coastal/offshore seabed during all project phases

Physical Damage to habitat

(indirect and longer-term damage to habitat)

PD

Changes to coastal and offshore habitat as a result of alterations to the wave climate or hydrodynamic regime from the presence of devices, power cables or cable armouring causing physical changes (including changes to sediment transport and/or sediment scour.

Damage to coastal/offshore seabed from hydrodynamic changes

Physical Damage to habitat

(indirect and temporary damage to habitat)

PD

Reduction in quality of foraging areas as result of damage to coastal and offshore habitat from baseline surveys (e.g. boreholes and trawls); from equipment use causing abrasion, damage or smothering during installation; from maintenance and removal of cables/devices or from scour, sediment transport and hydrodynamic change, and damage from chains anchoring devices during operation.

Damage to coastal/offshore foraging areas during all project phases

Physical Damage to species

(direct and temporary damage to habitat)

PD

Damage to seal haul out locations during the installation, decommissioning and operation of the cables and cable armouring.

Damage to seal haul out from cables or pipelines

Physical Damage to species

(direct damage to species from collision risk)

PD

Collision risk and possible mortality of species due to the presence of devices or from vessels travelling to and from the site (including above and below water collision risk and the influence of lighting); risk of entanglement following a collision with power cables or mooring elements.

Damage to species from collision, entanglement or disorientation

Non-Physical disturbance

(barrier to species movement)

NPD

Presence of structures or disturbance (noise or visual) resulting in a barrier to movement, migratory pathways and/or access to feeding grounds depending on array design.

Disturbance from introduced structures causing barrier to mobile species movement

Non-Physical disturbance

(disturbance to species)

NPD

Visual disturbance and exclusion from areas as a result of surveying, cable and device installation/operation and decommissioning activities and movements of vessels.

Disturbance (visual) from activities during all project phases

Non-Physical disturbance

(disturbance to species)

NPD

Noise/vibration disturbance and exclusion from areas as a result of vessels and other activities during survey work (e.g. seismic exploration and geophysical surveys), construction (e.g. piling, drilling, cable laying), operation (e.g. device noise), maintenance or decommissioning.

Disturbance (noise) from activities during all project phases

Non-Physical disturbance

(disturbance to^[34] species)

NPD

Impacts from Electromagnetic Fields (EMF) and thermal emissions on benthic invertebrates and electromagnetically sensitive fish and cetaceans interfering with prey location and mate detection in some species and creating barriers to migration.

Disturbance (EMF and thermal emissions) from activities during all project phases

Non-Physical disturbance

(exclusion/ displacement of species)

NPD

Presence of structures resulting in an exclusion/displacement of a species from the area.

Disturbance from introduced structures causing exclusion/ displacement of species

Toxic Contamination

(reduction in water quality)

TC

Spillage of fluids, fuels and/or construction materials during installation or removal of structures (devices and cables) or during survey/maintenance.

Contamination during surveys or maintenance activities

Toxic Contamination

(reduction in water quality)

TC

Release of contaminants associated with the dispersion of suspended sediments during installation or removal of structures (devices and cables).

Contamination during installations/removal of structures

Non-Toxic Contamination

(elevated turbidity)

NTC

Increase in turbidity (and possibly reduced dissolved oxygen) associated with the release of suspended sediments during installation or removal of structures (devices and cables).

Non-toxic contamination from increases in turbidity

Biological Disturbance

(introduction of non-native species)

BD

Introduction of new structures on the seabed providing new substratum that facilitates the colonisation and ingress of invasive non-native species.

Biological disturbance from non-native species on substratum

Biological Disturbance

(introduction of non-native species)

BD

Introduction and ingress of invasive non-native species as biofouling species on the surfaces of vessels or construction plant.

Biological disturbance from non-native species on vessels