Opening the Gates of the Pak Mun Dam: Fish Migrations, Domestic Water Supply, Irrigation Projects and Politics

Abstract

The Pak Mun Dam on the Mun River in Ubon Ratchathani Province in northeastern Thailand has long been one of the most controversial hydropower projects in Southeast Asia. The environmental and social impacts associated with blocking important fish migrations between the mainstream Mekong River and the Mun River Basin are particularly well known. Fishers, non-governmental organisations and academics have advocated for opening the gates of the dam either year-round or at least for an extended period, and especially at the beginning of the rainy season when a large number of fish migrate upstream. Crucially, however, the damʼs gates are not always opened at the beginning of the rainy season as required by previous agreements. Water management issues associated with opening the Pak Mun Dam have become increasingly complex and fraught because of additional challenges relating to the construction of new infrastructure such as irrigation dams on tributaries, and because of an increasing demand for piped domestic water to supply urban dwellers in Ubon Ratchathani City. In this paper, we adopt a political ecology approach to examine the present economic, ecological and political circumstances associated with the management of the Pak Mun Dam, including the trade-offs associated with different possible management decisions.