Case Study: Guarding the Pa Sak River, Thailand
Thailand, as in many of the ASEAN countries, has been rapidly growing and industrializing in the past few decades. Along with the benefits of this economic growth, there are also the associated costs, which often surface as unexpected externalities, such as air and water pollution.
While, according to the Water Environment Partnership in Asia (WEPA), Thailand’s overall surface water quality is rated fair and improving in the majority of its river basins, rivers in the south adjacent to the major city centers remain stressed by municipal and industrial pollution sources, resulting in harmful algal and bacterial blooms, anoxic events, and large fish kills. One such river, the Pa Sak, located within the Chao Phraya River drainage basin, has been heavily polluted over the years from municipal and industrial wastewater discharge. Several large and high profile fish kill events (e.g.
Trichopodus trichopteru - an abundant local species) has prompted the government to action, including the funding for real-time water quality monitoring projects.