The history of flood plain development and the levee construction of the Ishikari River down stream

Abstract

The agriculture development of Ishikari River down stream plains began at early period of Meiji. It was the important measure of the country, and we had many plans for such development programs. However, the prewar development speed was very slow because this area was snow cold district, peaty soft ground zone, and flood frequent occurrence zone. Postwar and the development finally kept smoothly.
The early maintenance of the levee which was a safe base of the community was request of the communities. However, the levee maintenance is affected by a natural condition, war, financial circumstances, and there is it in the maintenance way now.
In this article, I considered relations of flood plain development and the levee construction of the Ishikari River down stream historically. Theconcrete contents is the history of a formation process of flooding surface, flood plain development program, and the levee construction, development of the land use and the levee construction of the surface flood plain.
In addition, I considered the role that a levee served as from these histories.
As a resultof consideration, I made clear that the reliability improvement for safe security of the flood plain society. Furthermore, for lasting safe security of the future flood plain society, I showed the ideal method of a new levee security systemof administration.