Sectoral marine plan for offshore wind energy: social and economic impact assessment scoping report

A.13. Commercial Shipping

A.13.1 Sector Definition

This sector relates to the transport of freight and passengers both within Scottish waters and internationally. Shipping routes can be split into two distinct types; transiting vessels passing through Scottish Waters and vessels with either their origin or destination port within Scotland. This section also considered anchorages.

A.13.2 Overview of Activity

AIS density grid data ( Figure A.13.1) indicates that, in general, vessels move up the west coast of Scotland through the North Channel (or Straits of Moyle), the Minches, and east-west between the northern coast of the mainland and Orkney, from where vessels access the North Sea. Some of the areas showing the highest intensity of vessel movement include ferry routes ( e.g. between Northern Ireland and Loch Ryan, between the outer Hebrides and the mainland via the Sound of Mull and between the Shetland Islands, Orkney and the Scottish mainland) and around the Clyde. There is also an area of particularly high intensity of vessel movements around Fraserburgh, Peterhead and Aberdeen, related to the offshore oil and gas sector. To minimise collision risk, some heavily used areas have Traffic Separation Schemes ( TSS) which divides opposing traffic into lanes (see Figure A.13.1). Anchorages are located all around the Scottish coastline in inshore waters ( Figure A.13.2) but are located in highest densities along the west coast, Orkney, the Moray Firth and the Firth of Forth.

In 2013, shipping contributed an estimated £200 million GVA (17% of the UK total) and it was estimated 11,200 of the UK nationals employed in the shipping industry (31% of the UK total) were based in Scotland (Oxford Economics, 2015).

With regard to future trends, shipping volumes bear a direct relationship to the global economic market. As markets react to the changing financial situation, shipping lines respond with services to move goods and people. The most notable variable to affect the volume and intensity of shipping into the future will be the technology and innovations used to design future shipping. Ship design seeks for bigger, faster and more economic transhipment of goods and people ( ABPmer and RPA, 2013).

Figure A.13.1 shows an overview of commercial shipping activity in Scotland. Information sources that can be used in the assessment are listed in Table A.13.1.

Figure A.13.1 Commercial shipping activity in Scotland

Figure A.13.2 Anchorages

Table A.13.1 Information sources for the commercial shipping sector

A.13.3 Potential Interactions with Offshore Wind

Table A.13.2 shows potential interaction pathways between commercial shipping and offshore wind arrays and export cables. Based on the approach to scoping described in Section 2 in the main report, the table also records whether the interaction:

• Is not likely to result in a significant socio-economic impact on the sector; or
• Is likely to result in a significant socio-economic impact on the sector and hence will require a detailed assessment;

The rationale underlying this expert judgement is provided in the table. Where it is not currently possible to make a judgement regarding the likelihood of a significant socio-economic impact due to insufficient information (for example, in relation to the extent of overlap between a sector activity and the DPO Areas) the table indicates that scoping will be required to be undertaken once sufficient information becomes available. Furthermore, as described in the main report, there is currently no information regarding the likely location of export cable routes/corridors and as such, it is not possible to undertake a meaningful assessment of the potential for any sector activity/export cable interaction to give rise to significant socio-economic effects. Rather, the potential for any interaction will be identified in Regional Locational Guidance.

Table A.13.2 Potential interaction pathways

A.13.4 Scoping Methodology

A.13.4.1 Impacts to shipping/ferry routes

To determine where detailed assessments of the interaction may be required when DPO area locations are available, the following scoping criteria are proposed:

• Where DPO areas are transected by commercial navigation route(s) or ferry routes, the density of traffic should be assessed. If the average density of traffic is 5 or more vessel movements per day, a detailed assessment should be undertaken;
• If the DPO area is transacted by an IMO recognised "ship routeing system", a detailed assessment should be undertaken;
• However, if the spatial extent of indicative arrays is predicted to occupy less than 5% of the DPO area it has been assumed that spatial planning within the DPO area can be used to avoid significant impacts and no detailed assessment should be required.

A.13.5 Assessment Methodology

A.13.5.1 Impacts to shipping/ferry routes

Where scoping indicates that a detailed impact assessment is required, the cost of displacement of commercial shipping/ferry routes can be assessed based on the number of vessels potentially displaced (based on AIS data), the estimated potential extra steaming distance and time and average fuel and labour costs for commercial vessels.

A.13.6 Data Limitations

AIS A transmission is mandatory for commercial vessels above 300 GT and all passenger ships regardless of size. As a result, some vessel classifications are underrepresented in the AIS data, including: commercial vessels below 300 GT; recreational vessels (see Appendix A.12), fishing vessels (See Appendix A.7) and naval vessels on deployment (see Appendix A.8). AIS B is optional and may be carried by smaller vessels including recreational, fishing and smaller commercial craft.

AIS data collected by the Maritime and Coastguard Agency is monitored from terrestrial receiver stations. Reception range is therefore limited to line of sight and dependent on the power of the transmitting vessel (hence, larger vessels with transmitters mounted higher up are more likely to be received than smaller vessels). Therefore, AIS coverage is more defined closer to shore, and underestimated for vessel activity outside of the reception range ( i.e. further offshore).