The localized depression created on the seabed following the extraction of subsea infrastructure, often associated with water injection systems, is generally termed a “seabed gouge” or “excavation.” This refers to the physical void left behind after removing pipelines, umbilicals, or other components of the injection setup. The dimensions and characteristics of the “seabed gouge” will depend on the size and configuration of the infrastructure that was removed, as well as the sediment properties of the seabed. For example, a large pipeline removal will result in a more substantial “seabed gouge” than the removal of a smaller umbilical.
The formation of a “seabed gouge” carries environmental and operational implications. Environmentally, it can disrupt the benthic habitat, impacting marine life and potentially altering seabed morphology. Operationally, it poses risks to other subsea assets, such as trawling gear or future installation activities, if not properly managed. Historically, the creation of “seabed gouges” was not always a primary concern during decommissioning activities, leading to long-term environmental impacts. However, increasing environmental awareness and regulatory requirements have driven the development of strategies for mitigation and remediation.
