Inland waters support a rich aquatic biodiversity which occupies close to 2 million square kilometers in the ASEAN region, and this makes inland waters among the most diverse and productive natural habitats. Inland waters support several components of aquatic biodiversity including reptiles, amphibians, fish, mollusks, insects, other aquatic invertebrates, and water plants. Birds and several other migratory species in this region have a unique relationship with this ecosystem as it is among the
areas used as staging or feeding sites along the path of their migratory routes.
The region’s abundant freshwater resources receive 9.5 percent of the total global precipitation volume every year, and is endowed with 16.2 percent of the world’s total renewable water resources. The average annual per capita water resource available in the region is 12,980 cubic meters, a rate almost
double the world average.
Inland waters are the main sources of irrigation for agricultural areas in the region. The agricultural
sector consumes 85.5 percent of the total water withdrawals, followed by the industrial sector (7.8
percent) and domestic sector (6.6 percent). The well-being of ecosystems and humans strongly
depend on the vital ecosystem services that these provide.