Arase Becomes First Operating Dam To Be Demolished in Japan

Kumamoto Prefecture's Governor Yoshiko Shiotani has announced plans for the removal of the prefecture-run Arase Dam, marking the first time in Japan that an operating dam will be dismantled. The demolition will start as soon as the prefecture's water rights expire in March 2010; the prefecture plans to ask for only a seven-year extension when the current water rights run out in March 2003.

Completed in 1955, the hydropower dam is about 25 meters high, spans some 210 meters, and has a maximum capacity of about 10 million cubic meters.

While the Prefecture initially sought to continue the dam operation with the Ministry of Land, Infrastructure and Transport, residents near the Arase Dam demanded its removal, citing environmental problems such as red tides and foul smell, ground tremors caused by water discharge, and other adverse effects. The assembly of Sakamoto village, where the dam stands, adopted a written statement against renewing the water rights.

The Arase Dam supplies less than 1 percent of the annual electricity demand in the prefecture. Considering environmental costs and repair expenses imposed on the prefectural coffers, some people questioned the cost-effectiveness of continuous usage of the aging hydroelectric dam.

The removal cost will total about 4.7 billion yen (about U.S.$39 million). If subsidized by the government or other some other body, the prefecture will consider starting deconstruction ahead of schedule. As a start, it will form a project team to study demolition methods.

Japan today has around 3,200 dams, including those currently under construction. With more than 20 dams being completed every year, Japan is said to be the only member country of the Organization for Economic Cooperation and Development (OECD) that is actively promoting more large dams. One of the driving forces behind Japan's pro-dam stance is the country's large number of construction workers, who account for 10 percent of the work force.

Under these circumstances, this first-ever planned dismantling of a dam has drawn attention in Japan as a sign of change. Meanwhile, public funds totaling 410 billion yen (about U.S.$3.4 billion), including related costs, are being poured into the Kawabegawa Dam project to make a large flood-control dam on the Kumagawa River, upstream from the Arase Dam. The removal of the Arase Dam, together with a local community campaign against the construction of the Kawabegawa Dam, may affect river control policies and the future of the Kawabegawa Dam.


Posted: 2003/02/02 07:45:22 AM
Japanese version