RIVERS IN JAPAN 1998
CONTENTS
Water management
The Land and itfs River
Flood and sediment disaster
Flood damage prevention
Urbanization and flood damage
Integrated flood control measures
Housing development and flood control
Super levees for flood preparedness and
community development
The use of dams for flood control
Preventing sediment disasters
Coastline protection
Disaster recovery
Characteristic water resource
Serious consequences of drought
Diverse approaches to water resources
development
Improving water quality
Conservation
Restoring livable environments
Outline of the 1997 Amendment to the River Law
New system for planning river improvement
Drought conciliation
Fluvial forestation
Preventing illegal mooring
Preventing accidental water pollution
Japan, tough blessed with abundant natural beauty, is plagued by frequent natural perils including floods, landslides, earthquakes, tidal waves, and volcanic eruptions. With the enactment of The River Law in 1896, a regular flood control plan was established. In recent years, however, with urbanization resulting in greater damage from natural disasters, river maintenance projects have become even more essential.
Water management
Natural disasters are common in Japan. Urbanization has created new types of disasters (disruption of inner water, the triggering of landslides, etc) and increased water demand. Calamities and sudden water shortages can paralyze cities and impact heavily on everyday and economics activities. We implement various projects to protect the land and people and to create safe and comfortable living environments within the active society.
The Land and itfs River
Rivers in Japan are short and steep and flow rapidly and violently.
Moreover, the ratio between the normal volume of the flow and that during a
storm is extremely great.
Seeing the Joganji River in Toyama prefecture, Johannes de Rijke exclaimed, gRivers in Japan are like waterfallsh.
A Dutch engineer hired during the Meiji Era (1868 –19111), de Rijke contributed substantially to flood project in major rivers in Japan, such as the Kiso, the Nagara, and the Ibi Rivers, known as the gthree rivers of Kisoh.
De Rijkefs statement is an apt description. Rivers in Japan characteristically flow directly from mountain to sea. A great amount of rains falls on the Japanese archipelago during the rainy season (heavy rains of June and July) and typhoon seasons; and during periods of intensive rainfall, even a small stream that usually runs low may become a raging torrent.