Trenching and Burial of Submarine Pipelines

Abstract

There have been two kinds of requirement for pipeline trenching. In shallow water, on beaches and on tidal flats, usually within a few hundred metres of the shore line, there is a need for relatively deep trenches, so that the pipeline does not become exposed if storm action changes the level of the sea bed. In deeper water, pipelines need to be protected against trawl gear and anchors, and to be safe against changes in the bottom, as a result of local scour or of large-scale sediment transport phenomena such as sandwave migration. It may also be desirable to reduce wave and current forces by sheltering the pipeline in a trench.