AquaBiota has investigated the impact of shipping to provide a basis for the marine spatial planning mission held by the Swedish Agency for Marine and Water Management. Within the project two separate investigations have been performed in Kattegatt and at Salvorev north of Gotland. The project was carried out in collaboration with SSPA.
Investigation in Kattegatt
In Kattegatt the suggested area to be used by the shipping sector is evaluated both from the perspective of the spatial needs of the sector and in terms of conservation values. The investigation analyses the current traffic situation regarding the characteristics of the shipping traffic and compares this to the expected traffic after the implementation of the suggested new route systems in Kattegatt. The report also describes the known conservation values in Kattegatt, with focus on the valuable Natura 2000-areas that are located within or in close proximity to shipping routes and the area utilized by the shipping sector.
The results indicate that the width denoted to be utilised by the shipping sector in the marine spatial plan is essentially deemed well dimensioned and localised out of interest for maritime safety. The suggested new route systems are assessed to contribute to increased maritime safety and the traffic to become more localised, with less traffic outside the sea lanes. Since a large number of marine conservation values are very vulnerable to oil spills, and difficult to remediate, an increased maritime safety is considered to be important also from a conservation point of view. As there are indications that shipping may affect Harbour Porpoises, as well as other organisms in the ocean area, it is desirable that the width of the area to be utilised by the shipping sector does not exceed the width needed for a preserved maritime safety. Further, it is recommended to investigate the possibility of decreasing marine noise from the shipping sector in areas considered to be particularly sensitive to noise pollution, and to monitor valuable areas that have previously been investigated in Kattegatt to be able to evaluate the consequences of the changed shipping.
Tano, S., Forsman, B., Balosch, A., Andersson, A. 2017: Sjöfartens rumsliga behov och miljöpåverkan i Kattegatt – fördjupat underlag för svensk havsplanering. Havs- och vattenmyndigheten 2017:27.
At Salvorev the impact of shipping on conservation values are investigated, as well as the consequences that can be expected from the forecasted changes to shipping traffic in the area. The report describes the current shipping traffic in the area, and an assessment is made of how the shipping traffic over Salvorev would increase if traffic in the future is redirected from the route at Hoburgs Bank to the sea lane west of Gotland. In addition to this, a qualitative impact assessment is made of how shipping is affecting Natura 2000-areas, habitats deemed worthy of protection as well as important species such as Long-tailed Duck and Grey Seal.
The results show that the current shipping traffic at Salvorev is constituted of approximately 2 100 yearly passages, and that there are indications that the current traffic may negatively affect the conservation values in the area, but that it is difficult to assess to what degree. The elevated risk for oil spills in the area illustrates an increased risk profile for sensitive conservation values, such as wintering grounds for Long-tailed Ducks, the passage of ships may interfere with seabirds, and marine noise may for example negatively affect juvenile fish. The forecasted increase in ship traffic is expected to be substantial (16 000 yearly passages), which is assessed to result in an increased risk of ships running aground or colliding. Further, increased traffic of loaded oil tankers carries the risk of large oil spills with serious environmental impacts. This is also deemed to be the principally increased risk for the conservation values in the area, as several species and biotopes are considered vulnerable to oil spills. Particularly for seabirds this is considered to constitute a considerably increased risk to conservations values, as compared to the current traffic.
As the sea lane at Salvorev is only approximately half the width of the existing passage at Hoburg, and the condensed traffic conditions is complicated by a diagonally intersecting sea lane, it is recommended that an investigation of maritime safety is conducted if the discussed redirection is to be implemented.
Tano, S., Forsman, B., Balosch, A., Andersson, A. 2017: Sjötrafikbelastning på Salvorev, norr om Gotland. Havs- och vattenmyndigheten 2017:28.