Privacy notice Cookies notice

3.3 Methodology for Assessing Cumulative Hazards

The hazards identified in the FSA for the Array are also assessed for cumulative risks with other projects and proposed developments within the cumulative risk assessment. Given the varying type, status and location of developments, different scenarios have been considered in the cumulative risk assessment, which allocates developments into the scenarios depending upon the following criterion:

The scenarios and associated level of assessment undertaken for each, are summarised in Table 3.4.
The maximum distance within which developments are considered for the cumulative risk assessment is 50 nautical miles (nm) from the Array perimeter as set out in the Array EIA Scoping Report (Ossian OWFL, 2023), noting the UK Chamber of Shipping (CoS) indicated this was an appropriate value during consultation (see section 4). This distance is standard within NRAs and provides a good overview of cumulative traffic patterns.
An aggregate of the criterion can determine the relevant scenario(s) for each development. For example, if a development is located within 50 nm of the Array but does not impact a main commercial route passing within 1 nm of the Array and has low data confidence it may still be screened out of the cumulative risk assessment.
Outputs of the cumulative tiering process are given in section 14.

Tier	Minimum Development Status	Criterion	Level of Cumulative Assessment
Baseline	Under construction or Operational	Existing development.	Screened out of cumulative assessment as captured in the baseline.
1	Consented or under determination	May impact a main commercial route passing within 1 nm of the Array. Offshore wind farm within 50 nm. Subsea cable within 2 nm.	Quantitative assessment of vessel routeing
2	Scoped	Offshore wind farm within 50 nm. Subsea cable within 2 nm.	Qualitative assessment of vessel routeing
3	Pre-Scoping	Offshore wind farm further than 50 nm. Subsea cable within 2 nm.	Screened out