The impact of laying and maintenance of offshore pipelines on the marine environment and the North Sea fisheries

This paper reviews the impact of the laying and maintenance of offshore pipelines on the marine environment of the North Sea, with an emphasis on the interaction between the offshore oil and gas industry and the fishing industry. The paper describes the coating, laying, burying and surveying of pipelines. Both natural hazards (water movement, corrosion, sediment movement) and man-made hazards (anchors, fishing activities) are discussed. A case history of a pipeline floatation is given in more detail.

Further items are: fishery damage attributed to offshore activities, fishing activity in relation with pipelines, improvements of fishing gear to reduce the impact on pipelines and the biological effect of introducing structures on the bottom.

It is suggested to base the requirements for each new projected pipeline on a combination of considerations and to assess these requirements case by case instead of applying standard requirements on e.g. burial depth, trenching, etc.