Improving the evidence base for coexistence between offshore renewables and commercial fishing

Harding, J.; Boblin, E.; Coyle, A.; Andrews, J.; Fisk, V.; Page, A.; Cooper, B. (2026). Improving the evidence base for coexistence between offshore renewables and commercial fishing. Report by Intertek Metoc. Report for Offshore Renewables Joint Industry Programme (ORJIP).

@techreport{Harding-2026-2130966,
author = {Harding, J and Boblin, E and Coyle, A and Andrews, J and Fisk, V and Page, A and Cooper, B},
title = {Improving the evidence base for coexistence between offshore renewables and commercial fishing},
institution = {Intertek Metoc},
year = {2026},
month = {feb},
url = {https://www.carbontrust.com/our-work-and-impact/guides-reports-and-tools/orjip-improving-the-evidence-base-for-coexistence-between-offshore-renewables-and-commercial-fishing},
keywords = {Wind Energy, Fixed Offshore Wind, Floating Offshore Wind, Human Dimensions, Fisheries, Stakeholder Engagement},
}

Export Citation to BibTex

TY - RPRT
TI - Improving the evidence base for coexistence between offshore renewables and commercial fishing
AU - Harding, J
AU - Boblin, E
AU - Coyle, A
AU - Andrews, J
AU - Fisk, V
AU - Page, A
AU - Cooper, B
AB - Intertek Metoc (Intertek) was commissioned by The Carbon Trust, as part of The Carbon Trust’s Offshore Renewables Joint Industry Programme (ORJIP) for offshore wind, Co-Ex (main) project, to investigate improving the evidence base for coexistence between offshore renewables and commercial fishing. The primary objective of this project was to understand opportunities to increase available evidence to support decision making around fishing activities within or near Offshore Wind Farm (OWF) developments. This report presents the results of the project, broken down into three work packages: literature review and stakeholder engagement, a review of fishing gear penetration, and a survey and trial evaluation. The UK Government aims to nearly quadruple its 2023 offshore renewable electricity production to 50 Gigawatts (GW) by 2030. The current expansion of Offshore Renewable Energy (ORE) developments in the UK has led to an overlap in space between ORE projects and fisheries, these interactions are expected to become more frequent with ORE expansion plans. Such colocation instances can lead to increased risk to fishing gear and subsequent loss or damage to ORE infrastructure. All information presented within this report are based on current literature, regulations, industry guidance and advice as well as stakeholder viewpoints, which are relevant at the time of publication. As the industry develops and more research is undertaken, it is expected that some assertions about information presented in this report may change over time. Literature review and stakeholder engagement The literature review revealed limited publications on the impacts of OWFs on commercial fishing activity, with evidence of both displacement and coexistence. Coexistence success appears to be influenced by OWF design, management, and early stakeholder engagement, but the variability in outcomes highlights the challenge of addressing fisher concerns. While some fishers cite adverse impacts, these views often lack robust evidence, presenting an opportunity for industry collaboration to improve data collection and baseline information for Environmental Impact Assessments (EIAs). Positive effects, such as artificial reef benefits from OWFs, are challenged by stakeholders, and further research is needed to fully understand their impacts on commercial fisheries. Spatial mapping of the UK fishing fleet showed otter trawling to dominate UK fishing activities for vessels over 12 m in length, accounting for 63% of landings, focused on Scottish waters and the Central Irish Sea. Other fishing methods, such as dredging and beam trawling, are geographically concentrated in areas like the Irish Sea and Southern North Sea. Future OWF development areas in the UK are projected to overlap with fishing areas accounting for 7.3% of total UK fishery value (for vessels >12 m in length, based on averaged 2011-2020 figures), based on around 70 GW of planned Offshore Wind, while active OWFs (as identified in 2024) impacted less than 1% of fishing intensity. Key stakeholder recommendations to enhance coexistence include inclusive OWF design, early liaison plans, and improved evidence bases for impacts like electromagnetic fields and underwater noise. Data gaps, particularly for smaller vessels, complicate assessments of fishing intensity near OWFs. Stakeholders emphasise the importance of transparent collaboration, informed decisionmaking, and government involvement to navigate coexistence challenges. Successful examples of coexistence included Westermost Rough OWF and the lobster fishery in this area, this success was attributed to the work of the Holderness Fishing Industry Group (HFIG). Certain turbine and array cable layouts as well as fishing community funds highlight potential pathways, however costs associated with changes to design or siting of infrastructure can be extraordinarily high, and further constrained by other geological, environmental and engineering constraints, which can limit design flexibility and consequential project feasibility. It was also identified that spatial constraints and concerns around floating OWFs warrant attention in future planning. Fishing gear penetration Industry and maritime safety guidance strongly advises against any type of fishing where there is a known and charted cable, however, this is not currently written into legislation in the UK and interactions between fishing gear and subsea cables do occur. The maximum penetration depth observed in the literature review was 35 cm for soft sediment and 29 cm for coarse sediment (Eigaard et al., 2016; Szostek et al., 2022). However, these depths are estimated and not evidenced through experimental data or field observations. Outside of the UK, in the Baltic, otter trawl penetration depths of up to 30 cm have been observed (Jones, 1992). The maximum evidenced penetration ranged between 15 and 20 cm and was observed in a study of oyster dredging in gravel (Southern Science, 1992). This study collated measurements of fishing gear penetration across sediment types and water depths in 22 areas around the UK, focusing on offshore renewable energy (ORE) project regions. The average penetration depth ranged from 2.5 cm in gravel to 7.5 cm in sandy mud, with a maximum depth of 12.7 cm observed in sandy mud. Results largely aligned with existing literature, though the study recorded shallower penetration depths. This trend may reflect efforts by fishers to minimise seabed drag for fuel efficiency and gear preservation or could be influenced by sediment infill and natural reworking. In terms of subsea cable burial, it is important to note that target burial is based on a case-by-case assessment. Where cable burial is not feasible, external cable protection measures are often used to protect the cable. There are a variety of cable protection measures with rock berms, concrete mattresses, fronded mats, articulated pipe/cable protection systems and rigid concrete protection, most widely used in the industry. An overview of these options highlighted that all cable protection measures have the potential to result in the snagging and subsequent damage to commercial fishing gear and/or subsea cables. When deciding on the appropriate cable protection, there are numerous factors to consider, including cost, the environment, supply, and installation feasibility, therefore fishing is one of multiple factors to consider on a site-by-site basis. Survey and trial evaluation Surveys are critical to offshore renewable projects, addressing risks like cable exposure and snagging hazards. Pre-installation and monitoring surveys often use technologies such as Multibeam Echosounders, Side-Scan Sonar, and Remotely Operated Vehicles. Emerging tools like uncrewed vessels promise cost-effective solutions but are still in their infancy. Over-trawl trials are intended to determine snagging risks and potential fishing gear damage when being used over subsea cable infrastructure. A review of these trials around OWF export cables revealed methodological inconsistencies, such as varying survey designs, frequencies, and types of fishing gear tested. Key findings indicate that over-trawl trials produce localised results specific to the area used, vessel, and gear used at the time, making their outcomes limited without information of long-term risks. While over-trawl trials are intended to provide assurance to fishers to resume fishing in the over-trawled area, they are considered by some to instil a false confidence of safety, as a risk of snagging and damage still persists after an over-trawl trial. Commissioned surveys/trials, undertaken in a controlled environment, investigating trawl gear penetration in different sediment types and over different cable protection measures on a long-term basis could improve our understanding on the impacts of fishing over installed subsea cables, helping support decision making in this sector. Fishing gear trials looking into scallop dredges showed designs were identified which reduced damage to benthic fauna and decreased seafloor penetration. However, carbon emissions were not reduced through any noticeable lower fuel usage and some sites recorded high bycatch and debris volumes. The Hywind floating OWF static fishing gear trial, highlighted a proof of concept with static gear successfully operated within the prescribed areas of the OWF with no safety issues, gear snagging, or gear lost. However, as these static gear trials were undertaken on mobile fishing grounds the economic viability as a replacement fishing method is not yet understood. Future studies looking into the commercial feasibility of this colocation in operational OWFs is recommended to quantify results on a larger and longer-term basis. Cable Burial Risk Assessments (CBRAs) can be cost-efficient, site-specific, standardised methods that use reliable data to inform cable installation and burial depths, factoring in fishing risks and future threats, while adopting a cautious approach to ensure cable integrity. In some cases, modelling to support an assessment of seabed mobility, though costly and reliant on high-quality data, helps identify high-risk areas for cable exposure and supports risk assessments, monitoring strategies, and appropriate installation methods. Technologies like Distributed Acoustic Sensing, Distributed Temperature Sensing and Optical TimeDomain Reflectometer enable real-time cable monitoring, however, can be affected by environmental and technical factors. Future improvements, such as integrating Artificial Intelligence (AI) with vessel tracking systems could enhance cable monitoring and risk management
DA - 2026/02//
PY - 2026
SP - 143
PB - Intertek Metoc
UR - https://www.carbontrust.com/our-work-and-impact/guides-reports-and-tools/orjip-improving-the-evidence-base-for-coexistence-between-offshore-renewables-and-commercial-fishing
LA - English
KW - Wind Energy
KW - Fixed Offshore Wind
KW - Floating Offshore Wind
KW - Human Dimensions
KW - Fisheries
KW - Stakeholder Engagement
ER -

Export Citation to RIS

Abstract

Intertek Metoc (Intertek) was commissioned by The Carbon Trust, as part of The Carbon Trust’s Offshore Renewables Joint Industry Programme (ORJIP) for offshore wind, Co-Ex (main) project, to investigate improving the evidence base for coexistence between offshore renewables and commercial fishing. The primary objective of this project was to understand opportunities to increase available evidence to support decision making around fishing activities within or near Offshore Wind Farm (OWF) developments. This report presents the results of the project, broken down into three work packages: literature review and stakeholder engagement, a review of fishing gear penetration, and a survey and trial evaluation.

The UK Government aims to nearly quadruple its 2023 offshore renewable electricity production to 50 Gigawatts (GW) by 2030. The current expansion of Offshore Renewable Energy (ORE) developments in the UK has led to an overlap in space between ORE projects and fisheries, these interactions are expected to become more frequent with ORE expansion plans. Such colocation instances can lead to increased risk to fishing gear and subsequent loss or damage to ORE infrastructure.

All information presented within this report are based on current literature, regulations, industry guidance and advice as well as stakeholder viewpoints, which are relevant at the time of publication. As the industry develops and more research is undertaken, it is expected that some assertions about information presented in this report may change over time.

Literature review and stakeholder engagement

The literature review revealed limited publications on the impacts of OWFs on commercial fishing activity, with evidence of both displacement and coexistence. Coexistence success appears to be influenced by OWF design, management, and early stakeholder engagement, but the variability in outcomes highlights the challenge of addressing fisher concerns. While some fishers cite adverse impacts, these views often lack robust evidence, presenting an opportunity for industry collaboration to improve data collection and baseline information for Environmental Impact Assessments (EIAs). Positive effects, such as artificial reef benefits from OWFs, are challenged by stakeholders, and further research is needed to fully understand their impacts on commercial fisheries.

Spatial mapping of the UK fishing fleet showed otter trawling to dominate UK fishing activities for vessels over 12 m in length, accounting for 63% of landings, focused on Scottish waters and the Central Irish Sea. Other fishing methods, such as dredging and beam trawling, are geographically concentrated in areas like the Irish Sea and Southern North Sea. Future OWF development areas in the UK are projected to overlap with fishing areas accounting for 7.3% of total UK fishery value (for vessels >12 m in length, based on averaged 2011-2020 figures), based on around 70 GW of planned Offshore Wind, while active OWFs (as identified in 2024) impacted less than 1% of fishing intensity.

Key stakeholder recommendations to enhance coexistence include inclusive OWF design, early liaison plans, and improved evidence bases for impacts like electromagnetic fields and underwater noise. Data gaps, particularly for smaller vessels, complicate assessments of fishing intensity near OWFs. Stakeholders emphasise the importance of transparent collaboration, informed decisionmaking, and government involvement to navigate coexistence challenges. Successful examples of coexistence included Westermost Rough OWF and the lobster fishery in this area, this success was attributed to the work of the Holderness Fishing Industry Group (HFIG). Certain turbine and array cable layouts as well as fishing community funds highlight potential pathways, however costs associated with changes to design or siting of infrastructure can be extraordinarily high, and further constrained by other geological, environmental and engineering constraints, which can limit design flexibility and consequential project feasibility. It was also identified that spatial constraints and concerns around floating OWFs warrant attention in future planning.

Fishing gear penetration

Industry and maritime safety guidance strongly advises against any type of fishing where there is a known and charted cable, however, this is not currently written into legislation in the UK and interactions between fishing gear and subsea cables do occur.

The maximum penetration depth observed in the literature review was 35 cm for soft sediment and 29 cm for coarse sediment (Eigaard et al., 2016; Szostek et al., 2022). However, these depths are estimated and not evidenced through experimental data or field observations. Outside of the UK, in the Baltic, otter trawl penetration depths of up to 30 cm have been observed (Jones, 1992). The maximum evidenced penetration ranged between 15 and 20 cm and was observed in a study of oyster dredging in gravel (Southern Science, 1992).

This study collated measurements of fishing gear penetration across sediment types and water depths in 22 areas around the UK, focusing on offshore renewable energy (ORE) project regions. The average penetration depth ranged from 2.5 cm in gravel to 7.5 cm in sandy mud, with a maximum depth of 12.7 cm observed in sandy mud. Results largely aligned with existing literature, though the study recorded shallower penetration depths. This trend may reflect efforts by fishers to minimise seabed drag for fuel efficiency and gear preservation or could be influenced by sediment infill and natural reworking.

In terms of subsea cable burial, it is important to note that target burial is based on a case-by-case assessment. Where cable burial is not feasible, external cable protection measures are often used to protect the cable. There are a variety of cable protection measures with rock berms, concrete mattresses, fronded mats, articulated pipe/cable protection systems and rigid concrete protection, most widely used in the industry. An overview of these options highlighted that all cable protection measures have the potential to result in the snagging and subsequent damage to commercial fishing gear and/or subsea cables. When deciding on the appropriate cable protection, there are numerous factors to consider, including cost, the environment, supply, and installation feasibility, therefore fishing is one of multiple factors to consider on a site-by-site basis.

Survey and trial evaluation

Surveys are critical to offshore renewable projects, addressing risks like cable exposure and snagging hazards. Pre-installation and monitoring surveys often use technologies such as Multibeam Echosounders, Side-Scan Sonar, and Remotely Operated Vehicles. Emerging tools like uncrewed vessels promise cost-effective solutions but are still in their infancy.

Over-trawl trials are intended to determine snagging risks and potential fishing gear damage when being used over subsea cable infrastructure. A review of these trials around OWF export cables revealed methodological inconsistencies, such as varying survey designs, frequencies, and types of fishing gear tested. Key findings indicate that over-trawl trials produce localised results specific to the area used, vessel, and gear used at the time, making their outcomes limited without information of long-term risks. While over-trawl trials are intended to provide assurance to fishers to resume fishing in the over-trawled area, they are considered by some to instil a false confidence of safety, as a risk of snagging and damage still persists after an over-trawl trial.

Commissioned surveys/trials, undertaken in a controlled environment, investigating trawl gear penetration in different sediment types and over different cable protection measures on a long-term basis could improve our understanding on the impacts of fishing over installed subsea cables, helping support decision making in this sector. Fishing gear trials looking into scallop dredges showed designs were identified which reduced damage to benthic fauna and decreased seafloor penetration. However, carbon emissions were not reduced through any noticeable lower fuel usage and some sites recorded high bycatch and debris volumes.

The Hywind floating OWF static fishing gear trial, highlighted a proof of concept with static gear successfully operated within the prescribed areas of the OWF with no safety issues, gear snagging, or gear lost. However, as these static gear trials were undertaken on mobile fishing grounds the economic viability as a replacement fishing method is not yet understood. Future studies looking into the commercial feasibility of this colocation in operational OWFs is recommended to quantify results on a larger and longer-term basis.

Cable Burial Risk Assessments (CBRAs) can be cost-efficient, site-specific, standardised methods that use reliable data to inform cable installation and burial depths, factoring in fishing risks and future threats, while adopting a cautious approach to ensure cable integrity. In some cases, modelling to support an assessment of seabed mobility, though costly and reliant on high-quality data, helps identify high-risk areas for cable exposure and supports risk assessments, monitoring strategies, and appropriate installation methods.

Technologies like Distributed Acoustic Sensing, Distributed Temperature Sensing and Optical TimeDomain Reflectometer enable real-time cable monitoring, however, can be affected by environmental and technical factors. Future improvements, such as integrating Artificial Intelligence (AI) with vessel tracking systems could enhance cable monitoring and risk management