In 2015, Nord Stream 2 AG conducted reconnaissance environmental surveys for both route options shown in Figure 5-2 and developed high level design concepts in order to make an informed comparison of the two options, see also Atlas Maps AL-01-Espoo and AL-02-Espoo.
Based on the outcome of this evaluation, the Narva Bay route option was found to be the preferred option. The main reasons are:
• The route is shorter for both onshore and offshore segments, thus resulting in a smaller impact area and a shorter construction time frame;
• Seabed conditions are more favourable; therefore the total volume of required pre-lay trenching and seabed intervention works is significantly less.
- The total volume, and therefore duration, of required pre-lay trenching and seabed intervention works for the Narva Bay option is significantly less than for the Cape Kolganpya option.
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The impact on the marine environment for the Narva Bay option would be significantly less than for the Cape Kolganpya option. The extent and duration of sediment dispersion for the Narva Bay option is much lower than for the Cape Kolganpya option, and known contamination levels of the seabed sediments are lower.• The vulnerability of ecosystems as well as individual components of biodiversity and aquatic biological resources in the area of the Narva Bay route is lower than for the Cape Kolganpya option. However, for the onshore section of the Narva Bay route, mitigation is required to manage impacts on sensitive forest habitat. The Narva Bay route, therefore, would affect fewer valuable ecosystems and communities, including:
- Important bird areas and ringed seal haul-outs, where the average distance from the Narva Bay route is significantly greater than for the Kolganpya alternative and underwater noise impacts on marine mammals are lower.
This option would provide significantly greater technical security for pipeline construction and operation, which would mean reduced risks of accidents and emergency situations and associated large-scale environmental impacts.
• The environmental and social impacts associated with the upstream gas pipeline that is required to supply the compressor station would also be greater along the Cape Kolganpya option because of its encroachment of the Kotelsky state complex nature reserve.
Final decision on approval of this route will be given by the Russian Federation authorities based on a detailed analysis of environmental damage prepared for both options and evaluation of the final outcome of the Russian environmental impact assessment (EIA).
Detailed discussion and assessment of alternatives is provided in the Russian EIA and in an Assessment of Alternatives report which will be publically displayed as part of the national procedure.
Figure 5-2 Project alternatives in the Russian Federation.
Alternative routes for NSP2 in the Finnish EEZ 5.4.3
In the Finnish EEZ, the proposed NSP2 route crosses the existing NSP pipelines immediately after entering the Finnish sector. The subsequent route lies north of the NSP pipelines.
The length of the Finnish section is approximately 378 km from KP 114 to KP 492). The Finnish EIA report includes assessments of the following alternatives: NSP2 route, sub-alternatives, non-implementation.
In the Finnish EEZ, there are two sections along the pipeline route where the route divides into two alternative routes, see /27/ and Atlas Maps AL-01-Espoo ro AL-02-Espoo. The eastern section is located south or south-west of Porkkala in the Gulf of Finland, and the sub-alternatives are called ALT E1 and ALT E2. Another section is located in the northern Baltic Proper in the western part of the Finnish EEZ, and the sub-alternatives are called ALT W1 and ALT W2.
Figure 5-3 Pipeline route and route alternatives in the Finnish EEZ.
The main characteristics of the four sub-alternatives are shown in /27/.
Table 5-1 Comparison of sub-alternatives ALT E1 and ALT E2.
ALT E1 ALT E2 ALT W1 ALT W2
Length (km) 20.5 – 20.8 19.8 – 20.1 59.1 – 60.1 56.3 – 57.0
Rock volume (m3) 121,000 279,000 340,000 282,000
Freespans > 100 m 9 15 40 25
Number of crossings 18 8 8 4
Minimum depth (m) 33.2 – 35.4 45.9 – 48.5 45.2 - 54.9 82.9 – 87.1 ALT E1/E2
The southern sub-alternative ALT E2 is about 700 m shorter than ALT E1. The seabed profile along ALT E2 is more irregular. Therefore the estimated number of long freespans and the rock volume required for intervention works are higher. Both sub-alternatives are mostly in the range of 50-70 m water depth, but ALT E1 runs through a short shallow water section where the minimum water depth is 33 m. There are more cable crossings with ALT E1 than with ALT E2.
ALT E2 is located closer to NSP than ALT E1 (0.2 km at its closest point).
ALT W1/W2
The southern sub-alternative, ALT W2, is about 3 km shorter than ALT W1. The seabed profile along ALT W1 is more irregular. Therefore the estimated number of freespans and the rock volume required for intervention works are higher. Both sub-alternatives are mostly in the range of 80-160 m water depth, but ALT W1 runs through a short shallow water section where the minimum water depth is 45 m. There are more cable crossings with ALT W1 than with ALT W2.
ALT W2 is located closer to NSP than ALT W1 (0.2 km at its closest point).
The environmental impacts of the sub-alternatives are assessed on an equal basis in the Finnish EIA and in Chapter 10 – Assessment of environmental impacts.
Alternative routes for NSP2 in the Swedish EEZ 5.4.4
Three different route alternatives have been identified during the design and planning of NSP2 through Swedish waters: the route east of NSP (ES route), the route west of NSP (FS-new route) and the alternative route (RA route), see Figure 5-4, Atlas Map 01-Espoo and Atlas Map AL-03-Espoo.
Figure 5-4 NSP2 route alternatives in the Swedish EEZ.
It should be noted that since the initial alternative route assessment was carried out, a new Natura 2000 area has been designated by the Swedish authorities, within the Swedish EEZ and named ”Hoburgs Bank and Norra Midsjöbanken”. The area is an extension of the existing sites Hoburgs Bank and Northern Midsjö Bank (see Section 9.6.6). This new protected area has been addressed and assessed in the national Swedish application documents.
ES route – east of NSP
The ES route branches off from the old FS route north-east of Gotska Sandön, crossing the existing NSP and running mostly parallel to the existing pipelines on the eastern and south-eastern side for the rest of the NSP2 section in the Swedish EEZ. The ES route has a greater distance from the Natura 2000 sites of Hoburgs Bank and Northern Midsjö Bank compared with NSP and is closer to the deep water shipping channel.
FS route – west of NSP
Originally the FS route was thought to run parallel to NSP on the west and north-western side for the entire section in the Swedish EEZ. On account of new circumstances, the FS route from the NEXT phase was amended and became the FS-new route. The FS-new route follows the ES route from the start of the Swedish sector at the Finnish border to midway through the Swedish EEZ to take into account the recently installed Sea Lion submarine cable between Finland and Germany.
It then crosses NSP and joins the originally intended FS route down towards the Danish EEZ border, crossing NSP again and re-joining the ES route. The FS-new route is closer to the Natura
2000 sites of Hoburgs Bank and Northern Midsjö Bank than NSP. Consequently, the distance from the route to the deep water shipping channel is greater compared with the ES route.
RA route – south of NSP
The RA route is in the southern part of the Swedish EEZ that originates from the ES route, crossing the border to the Danish EEZ further south. The RA route enters the Danish border through the Bornholm Deep. This route is the shortest option, but it does not run parallel to the existing NSP. The route also passes through the anchoring restriction area that surrounds the chemical munitions dumping site east of Bornholm.
The three route alternatives for NSP2 in the Swedish EEZ have been considered in relation to the relevant technical, safety, environmental and socio-economic aspects. The routes have been compared and experience and alternatives from NSP and the NEXT feasibility study have been considered in the evaluation and selection of the preferred route.
For the majority of the aspects, the ES route is favourable compared with the FS-new route. The FS-new route includes two additional crossing sites of NSP compared with the ES and RA routes.
The crossings will result in significantly increased intervention works. In addition, the ES route is located further away from the Natura 2000 sites of Hoburgs Bank and Northern Midsjö Bank, which is favourable from an environmental point of view.
The RA route alternative crosses the important fishing grounds of Bornholm Deep and therefore would interfere more with fishery than the ES route and FS-new route. In addition, the route deviates from the existing NSP, while the other alternatives remain parallel to NSP, and is therefore considered less favourable in relation to marine spatial planning. The majority of the RA alternative is located in the Danish EEZ, where it crosses an area that is potentially contaminated by CWAs associated with a chemical munitions dumpsite.
The preferred route in Sweden that has been selected for assessment in the Swedish ES and in Chapter 10 – Assessment of environmental impacts is the ES route.
Alternative routes for NSP2 in Danish waters 5.4.5
Two different route alternatives have been identified during the design and planning of NSP2 through Danish waters: the route east of NSP (ES route) and the alternative route (RA route), see Figure 5-5, Atlas Map AL-01-Espoo and Atlas Map AL-04-Espoo.
Figure 5-5 NSP2 route alternatives in Danish waters.
RA route – alternative route
The RA route does not run parallel to the existing NSP and crosses approximately 40 km of the area that has restrictions on anchoring and fishing due to the potential presence of chemical munitions or CWAs, see also Section 5.4.4. Although shorter, and therefore less expensive to install, it can be assumed that the risk of encountering chemical munitions is high compared with other areas. This would present health and safety concerns during construction and operation of the pipelines and has the potential to impact the marine environment.
ES route – east of NSP
The ES route runs parallel to the NSP route for the whole pipeline section inside Danish waters and is located outside the area that has restrictions on anchoring and fishing due to the potential risk of chemical munitions and CWAs. As the ES route runs parallel to the NSP route, this is advantageous in terms of marine spatial planning. The occupied area which could affect other uses of the seabed is thus reduced to a minimum.
Furthermore, it has been assessed in the Danish EIA that impacts, especially on CWAs, fishery and military areas, would be lower for the ES route than for the RA route /26/.
The preferred route in Denmark that has been selected for assessment in the Danish EIA and in Chapter 10 – Assessment of environmental impacts is the ES route.
Alternative routes for NSP2 in German waters 5.4.6
The route planning and landfall assessment in Germany considered a wide area of options, which was narrowed to the selection of a preferred landfall alternative and route as follows (see also Atlas Map AL-01-Espoo and Atlas Map AL-04-Espoo):