River Resources Allocation and Participatory Irrigation Management in Japan Today

Abstract

In Japan, the main source of irrigation is not ground water but river water, which is allocated among water users such as irrigation associations, mayor to supply domestic water, and CEOs of manufacturing companies to use water by water right systems or by the permission of the Minister. The amount of river water administratively available to water users is “Normal” low flow discharge with a risk of 10% probability exceeding “River Maintenance” flow. The Irrigation Associations or (farmers') Water Users Associations, called “Land Improvement Districts” in Japan, are managed to satisfy the requirements of PIM, 1) to establish democratic farmers' irrigation associations, 2) to collect water charge from farmers. In principle, the construction costs of the projects are subsidized, but the operation and maintenance costs are not subsidized.