Some Geotechnical Aspects of Land-to-Sea Transition Zones

ABSTRACT: The transition between land and water, whether in lakes, rivers, and ocean shorelines, often presents special challenges by virtue of geological conditions as well as the geotechnical aspects relating to design, construction and operation of facilities located in such zones or activities which may take place in them. The transition zones often contain beaches which can be prominent features, particularly in areas with high tidal ranges. Structures in transition zones may include transportation facilities (such as roads, bridges, causeways, and tunnels), wharves, harbors, pipelines, power stations, sea defence and coastal management works, pumphouses and intakes, and residential areas. In terms of operations, such zones are significant from both civilian and military standpoints. Civilian activities include dredging, mining, reclamation, environmental protection, marine salvage operations, exploration, and specialized construction. From a military standpoint, such zones are obviously important in respect to amphibious landings and shoreline defense installations. The paper will review the special geotechnical issues associated with land-to-sea transition zones and present several case histories from the Authors’ experience, pertinent to such zones.