Skip to content

Feedback collected in the Bay of Bothnia on map markings of Aids to navigation to be removed for winter

Published 15.11.2023

In the Bay of Bothnia, a new experiment on map marking operating models will be launched in the winter season 2023–2024. The aim of the operating model is to specify the map markings of Aids to navigation (AtoN) to be removed during the winter season to better correspond with the actual situation at sea.

The Finnish Transport and Communications Agency Traficom, the Finnish Transport Infrastructure Agency and Fintraffic’s Vessel Traffic Services will collaborate to collect feedback on the functioning of the operating model from vessels moving in the area during the coming winter season.

In the Bay of Bothnia, the demanding winter season requires the practice of removing some of the AtoN for the season. This ensures that the AtoN cannot move from their places, for example as a result of ice movements. 

In the upcoming operating model experiment, map markings will be specified as follows:

  • ENC AtoN markings will remain the same throughout the year, and the point category ‘Caution area' is added to the ENC material for AtoN removed during the winter season. 
  • The absence of physical  AtoN is reported by means of virtual AIS -Aton transmissions and by placing the text "Withdrawn" in the name of the AIS- AtoN. The transmission is switched on when the buoys are lifted out during November, and switched off when the buoys are reinstalled, no later than 15 June 2024.

In the operating model experiment, feedback will be collected from vessels during the winter season 2023–2024. In particular, we hope that vessels will send images of their AtoN views (ECDIS and radar equipment), but other feedback will also be important in the further development of our operations. Please send your feedback by email to  [email protected]

Bay of Bothnia AtoNs included in the experiment on operating models for map markings:

1 Left buoy, TL-88397 "Ke 4" 65°26.4987'     24°13.2516'
2 Right buoy, TL-88399 "Ke 3" 65°24.5831'     24°08.6874'
3 Left buoy, TL-88398 "Ke 2" 65°23.9503'     24°05.3643'
4 Right buoy, TL-88395 "Ke 1" 65°22.8921'     24°03.4679'
5 Right buoy, TL-85067 "O1A" 65°20.2617'     23°57.7057'
6  Right buoy, TL-53071 "East Northern Quark no 2" 63°27.0261'     20°38.3294'
7 Right buoy, TL-45946 "Waldersgrund"   63°25.1980'     20°35.7460'
8 Right buoy, TL-8756 "Norrskär North" 63°18.7074'     20°35.7408'
9 Right buoy, TL-8749 "Gloppet" 63°16.1084'     20°48.0817'

The operating model experiment for the winter season 2023–2024, which will begin in the Bay of Bothnia, will be carried out as a cooperation between Traficom, the Finnish Transport Infrastructure Agency, and Fintraffic. Traficom acts as the AtoN autherization authority and Finnish nautical chart authority, the Finnish Transport Infrastructure Agency maintains aids to navigations, and Fintraffic’s Vessel Traffic Services are responsible for Finland's AIS broadcasts.