| Abstract: | Water in the shape of rivers, lakes, fjords, oceans and so on, sometimes seems to provide a barrier to improving the environment and preventing further development. Hitherto unconsidered options may be available to cross over or under a water barrier. Without full knowledge of the available possibilities, planners and decision-makers are not able to make the best-informed choices. This paper initially examines the relative attributes of bridges, ferries, submerged floating tunnels, immersed tunnels, soft ground tunnels and rock tunnels. Reasons for selection or rejection of each option are discussed. The paper goes on to introduce immersed and floating tunnels in more detail. Specific examples are given to convey the concepts. |
