The dataset was created in order to update the information regarding underwater cables in the Baltic Sea Region for the HELCOM Assessments. Data was collected by the HELCOM Secretariat during 2015 and 2016. The dataset contains information on submarine cables in the Baltic Sea. The dataset is based on available public sources on cables and due to variety of data sources (national and international), should be taken as general data based on best available public data with variable resolution over the different region in the Baltic. For Danish areas, the data represents constructions on Danish territorial waters, authorized facilities and activities from 2015. Depending on area, more accurate spatial data might exist, but data is unavailable for public use. National data submissions from Latvia and Russia were not available. For 2018 version of dataset, cables that have only approximate location were removed from the dataset, as the spatial accuracy of these objects is not sufficient for the scale of the index. Attribute specification and units NAME COUNTRY CAPACITY (MW) STATUS (Operational, Under Construction, Application Submitted, Planned, Unknown) SOURCE

The dataset contains cables in the marine environment that was made available by HELCOM Contracting Parties in response to a data call. Data were collected by the HELCOM Secretariat in 2022. Data were reported in polylines (Estonia, Finland, Poland, Denmark and Germany) and polygons (Poland). For Estonia and Sweden, HOLAS3 dataset was supplemented with HOLAS2 data. Attribute specification and units with predefined values specified from the data call Status: The status of the cable harmonized with the values from a predefined list (operational, under construction, application submitted, planned, approved, other), and following a precautionary approach that attributed the value operational for values that were out of the predefined list Type: Cable type (telecommunication, power, other) Capacity: Potential capacity of the cable or amount of data Unit: Capacity unit (kV or GB) Year: Year the cable was built Cab_prot: Specify the type of cable protection (none, sediment fill, rock fill, other) Sediment: Sediment type (mud, sand, hard, substrate, mixed sand, other) Cab_posit: Cable position in the seabed (in the sediment, on the sediment) Lay_depth: Laying depth in meters Refiling: Refilling of the trench (YES, NO) Method: The method utilized when laying the cable (digging/dredging device [open, enclosed], suction device, flushing, other) Cab_width: Widht of the cable Notes: Notes regarding the reported data and HOLAS 2 data indication. orig_stats: Original status declared by the Contracting Parties