Examining the worthiness of dam projects is an important promise of the Democratic Party of Japan. The party's manifesto for the 2009 Lower House election called for halting the construction of the Yanba dam in Gunma Prefecture and the Kawabegawa dam in Kumamoto Prefecture.

Once large-scale public works projects are started it is extremely difficult to halt them. It has often been pointed out that such projects, especially dams, are a waste of public money. In view of the central and local governments' dismal financial situation and the ongoing depopulation of the countryside, it is questionable whether these dam projects are necessary. It is logical that the government investigate alternative means of flood control.

Efforts to review the worthiness of dam projects began last month at various locations around Japan. Involved are 30 dam projects under the jurisdiction of the central government and 53 dam projects under the jurisdiction of prefectural governments with subsidies from the central government.