In recent years, environmental degradation has become an increasing concern in Thailand. Of the environmental problems and challenges facing the Kingdom, water pollution is one of the most serious. Among the rivers in Thailand, the Chao Phraya River is the most contaminated. Recently, the Pollution Control Department (1997) reported that the levels of dissolved oxygen in the lower reaches of the Chao Phraya River have been close to zero since 1990, and that by the year 2000, the "King's River" may well be "dead". The finality of this observation is not just an academic hyperbole