As the blue economy expands, the increased scale and frequency of marine industries further increases the risk of cumulative impacts on the environment. Quantitative cumulative impact assessments (CIAs) are needed to understand potential impacts but require interoperable ecological datasets across broad spatial and temporal scales, yet data availability remains inadequate. Two barriers constrain data availability: interoperability barriers prevent dataset integration due to a lack of standardised survey designs and methods, and commercial barriers restrict data sharing due to commercial risks including loss of competitive advantages. We propose a novel data infrastructure comprising a five-stage pipeline that addresses both barriers through FAIR (Findable, Accessible, Interoperable, Reusable) data principles (ensuring interoperability through consistent data standards), and a secure analysis platform (enabling data use without raw data access). We demonstrate this pipeline through a CIA of benthic habitats applied to one of six declared Offshore Electricity Infrastructure (OEI) zones critical to Australia’s energy transition. The demonstration shows how the proposed data pipeline can support compiling of private and open-access data sources to improve the precision of impact predictions, and enable assessment across the broad spatial scales required for CIAs. The pipeline has immediate applications across offshore wind zones (e.g. Australia, North Sea) and multi-industry user environments. Broader adoption of FAIR-compliant standardisation could transform CIA from project-specific assessment to proactive ecosystem health monitoring. This pipeline provides an operational blueprint for increasing data interoperability and availability to enable the quantitative CIA necessary for rigorous environmental protection that is increasingly advocated in regulatory guidance.