Utilization of Environmental Water Resources in the Reconstruction of Otsuchi Town After the 2011 Tsunami

Abstract

In Otsuchi Town, which suffered the effects of a tremendous tsunami in 2011, civil engineering reconstruction work is now progressing rapidly. In such situations, if the scale of a reconstruction project is excessive and assessments of the condition of the water environment are made too hastily, a burden in excess of that caused by tsunami damage itself might be placed on the aquatic ecosystem. In the Otsuchi case, concern has arisen about the deterioration of natural springs caused by the construction of embankments, landfill and floodgates, as well as the fact that the inland water has become disconnected from the sea due to the formation of a huge tidal breakwater. These aspects could possibly cause the degeneration of the spring water environment, thereby jeopardizing the region’s principal “local blessing”, namely its high-quality natural water resources. Responding to these challenges is not only a matter of preserving biodiversity, but is also a serious matter for the future development of Otsuchi Town, especially given its long history of enjoying the benefits of its natural water springs and the sea. In this context, there is a danger that any civil engineering reconstruction project might destroy the attractiveness of the region and cause disruption to future town management. Even 2–3 years after the earthquake, the plan for a so-called ‘Reconstruction Park’ in the disaster risk area was only a sketchy outline with no firm budget. However, since the early summer of 2014, the town administration has devised more concrete plans for the construction of embankments, floodgates, and tidal banks. A full-fledged study on the content of reconstruction work was initiated, based on the results of research carried out by local authorities. Having established a forum for the exchange of views among the local authorities and specialized researchers, I believe that Otsuchi Town’s natural resources, its flora and fauna, and its water environment should be regarded as “local blessings”. On that basis, I recommend in this chapter some rational and scientific contributions to town planning in the reconstruction of Otsuchi town.