Mekong Dam Victims - Thailand. The Pak Mun dam with open gates. The building of the Pak Mun Dam in Thailand has lead to strong opposition by the local population as the number of fish and fish species in the river is dramatically reduced because of the dam, affecting more than 20,000 people. Known as "The Mother of Waters", more than 60 million people depend on the Mekong river and its tributaries for food, fresh water, transport and other aspects of daily life. The construction of big dams is now threatening the life of these people aswell as the vital and unique ecosystem of the river.