6. Further processing of the AoS
The initial constraint output provides a guide as to the relative suitability of the study area for offshore wind energy projects. By avoiding areas with the highest levels of constraint, the resulting AoS are the first step towards identifying the locations potentially suitable for development. As such, the multi-criteria analysis serves as a useful and versatile tool to visualise many spatial layers of information simultaneously. However, the multi-criteria analysis could potentially lead to some individual issues being obscured where a greater density of constraint layers create a cumulative effect elsewhere
A selected set of interactions have been overlaid individually on the AoS to visualise where some of the single issues that are more likely to create barriers to development exist. These single issues can act to significantly limit or delay development opportunity, but may not have registered in the constraint output as high. This exercise was undertaken to alter or remove parts of AoS that had high probability of conflict with the principal single issue users of the sea.
The single issue interaction layers used to revise the AoS were:
- Fishing- offshore fishing intensity data (
information on vessels larger than 15 m in length) were used to
further identify likely interactions fishing types included:
- Scallop dredging
- Nephrops trawling and creeling
- Demersal trawling
- Pelagic trawling
- Crab and lobster creeling
- Shipping traffic- processed AIS data for all vessels for the year 2015 were used to discern the most heavily used routes and to draw the revised AoS around them.
- Nature protected sites- overlap with all MPAs, SACs, SPAs, Offshore SACs, RAMSAR sites, draft offshore SPAs and SSSIs was considered and changes made to avoid likely constraints.
- Oil and gas installation locations in the eastern North Sea overlapped with some of the AoS. The AoS were revised to decrease the overlap with oil and gas clusters.
Given that this process splits the AoS using these layers as a guide the resulting revisions are more numerous but individually cover a smaller area. The resulting revised AoS are shown in Figure 28 together with the originally identified AoS. Table 4 lists the names given to these revised AoS as well as the area they cover and what SORER area they are predominantly within.
Figure 28: Revised AoS to account for the foreseeable impacts of single issue activities. This includes fishing, shipping traffic, oil and gas infrastructure and overlap with designated nature protected areas. © Crown copyright and database rights (2018) OS (100024655).
Once the process of consultation on these AoS begins, the stakeholders may alert MS to interactions that could further alter their spatial extent.
Table 5: Names and area in km 2 of the revised AoS, the SORER area in which most of their area falls into is indicated also.
|Area km2||AoS name||SORER occupied|
6.1 Detailed description of the modifications applied to the initial AoS
The opportunity and constraint mapping process described above provided an initial set of AoS. These areas were presented at various workshops held early in the initial scoping stage to relevant stakeholders such as representatives of the OW industry, Scottish nature conservancy organisations, Royal Yachting Association and fishing industry representatives among others. As a result of feedback from these events and a more detailed single issue analysis the AoS have been further refined. The changes made to each of the areas are described below. The process of AoS revision follows the SORER regions.
6.1.1 South West
The Areas of Search Study has not identified any options in the South West Region, as Scottish Ministers' have previously ruled this region unsuitable for development in both 2011 and 2013, with the consideration to the potential adverse, economic environmental and visual impacts, and the related community concerns raised in the assessment and consultation processes at the time. Scottish Ministers' intend to maintain this position for the development of the new Sectoral Marine Pan for Offshore Wind Energy, unless sufficient evidence to the contrary is presented during the initial scoping stage consultation.
Figure 29: Detail of the south west SORER area. No AoS have been identified at this location. © Crown copyright and database rights (2018) OS (100024655).
The opportunity and constraint mapping exercise identified a large potential AoS ( AoS 6) that extended from the west coast of Islay, north west to the west coast of Barra.
Further analysis of the individual constraints that may affect this location suggested that the AoS should be divided into three distinct areas. High levels of shipping traffic are found in this area leading to the route between Scotland and Northern Ireland. Accordingly, a large section of AoS 6 (west and south west of Tiree) has been removed to allow suitable space for the shipping traffic. The remaining northern section (W1) has been slightly modified to account for the deep water channel, whilst the west section (W2) was also reduced in size to account for the shipping traffic. W3, the remaining section north west of Islay, has also been reduced in size to account for the shipping traffic to the west and for potential visual impacts at the east coast of Islay.
Both W1 and W3 include large sections of the existing Draft Plan Options (Marine Scotland, 2013a), adjusted for updated opportunity and constraint mapping.
Figure 30: Detail of the west SORER area showing how AoS 6 has been modified. © Crown copyright and database rights (2018) OS (100024655).
6.1.3 North West
A large AoS ( AoS 4) bridged the North West and North regions. In the North West region, this AoS occupied the area between Lewis and mainland Scotland and extended north past North Rona. The AoS has been split in two ( NW1 and NW2), accounting for shipping traffic as described by the AIS data above. This partition will allow for shipping traffic navigating around Scotland, specifically those vessels which will make use of the deep water channel to the west of Lewis.
Additionally, the opportunity and constraint mapping process highlighted a potential area of opportunity further west of Lewis which was not originally considered in the initial AoS exercise. This new AoS ( NW2) has now been included. NW2 includes the area north west of the deep water channel north of Lewis. The area selected excludes a location identified as containing a high level of fishing activity and remains distant from North Rona and Sula Sgeir, avoiding the SPAs in the same location. The opportunity and constraint exercise also suggested that the area between Lewis and the deep water channel could offer a potential area for offshore wind development. However, the potential visual impact at this location would suggest that the more distant AoS ( NW2) is more appropriate.
Figure 31: Detail of the north east SORER area showing how area 4 has been modified. © Crown copyright and database rights (2018) OS (100024655).
In the North region, AoS 4 extended from the east of North Rona, down to the north coast of mainland Scotland, avoiding the Solan Bank Reef SAC. It extended east encompassing much of the west coast of Orkney and also the existing wind Draft Plan Option.
As a result of further analysis of single issue constraints, this AoS has been reduced to two smaller areas. N6 is now located off the north coast of mainland Scotland encompassing an area between higher levels of shipping traffic. Similarly, N5 off the east coast of Orkney is situated within the previous Draft Plan Option but now encompasses a much reduced area due to shipping traffic and higher levels of fishing activity in the area.
North of Shetland, the opportunity and constraint exercise identified a large potential area of search. This AoS ( AoS 1) remains unchanged following examination of specific single issues.
AoS 2 east of Shetland covered a large area along the east coast of Shetland. Whilst the opportunity and constraint exercise highlights this a potential area of opportunity, including the previous Draft Plan option, looking specifically at the demersal fishing activity in the area suggests that the southern section of this AoS could be reduced. N7 now includes only the northern most section of the previous Draft Plan Option.
AoS 3 extends from the east coast of Orkney south into the Moray Firth and further east. Specific analysis of individual issues, including shipping traffic, fishing activity, oil and gas infrastructure and suggested helicopter routes to oil and gas locations suggested that this large AoS should be split into several distinct AoS. Four of these distinct areas are now located in the North region. N1, N2, N3 and N4 occupy areas of low shipping traffic whilst also allowing for helicopter routes through to the oil and gas infrastructure to the east.
Figure 32: Detail of the north SORER area showing the modifications to AoS 3, AoS 4 and part of AoS 2. © Crown copyright and database rights (2018) OS (100024655).
Figure 33: Detail of the north SORER area showing the modifications to AoS 1 and 2. © Crown copyright and database rights (2018) OS (100024655).
6.1.5 North East
As in the North region, AoS 3 has been divided into distinct smaller areas in the North East region. In addition to accounting for shipping traffic, a high level of fishing activity was already identified during the initial opportunity and constraint mapping process and this area was removed from the initial AoS. This area remains excluded in the new AoS and that location, between NE4 and NE5, has now been expanded.
Much of AoS 3 in the Moray firth has been reduced, due to anticipated visual impact issues and shipping traffic. NE6 and NE7 remain as AoS within the Moray Firth occupying areas with lower constraint.
These refinements have removed the previous Draft Plan Option, north east of Fraserburgh, from the AoS.
Further south, AoS 5 extended across the North East and East regions. Whilst the opportunity and constraint exercise identified a large initial area of search, a single issue analysis recommended reducing the AoS inside the North East region. Shipping traffic closer to shore was taken into account and an area of focused pelagic and demersal fishing indicates potential conflict that is not clear in the opportunity and constraint mapping exercise. Accordingly, the north section of AoS 5 has been reduced to two smaller AoS ( NE1 and NE2) which account for these additional constraints.
Figure 34: Detail of the north east SORER area showing the modifications to AoS 3 and 5. © Crown copyright and database rights (2018) OS (100024655).
As above, AoS 5 has been modified after further analysis of single issues. E2 and E3 both represent areas of greater opportunity but are reduced from the original AoS 5 so as to account for higher levels of shipping traffic and common shipping lanes. The same fishing activity as described above resulted in E2 and E3 not extending any further to the north. The new AoS were modified to account for the Marine Protected Areas ( MPA) in this region.
Figure 35: Detail of the east SORER region showing the modifications to the southern part of AoS 5. © Crown copyright and database rights (2018) OS (100024655).