15. Water, hydropower, and aquaculture. A total of 60% of Viet Nam’s total river flow and 95% of the Mekong River’s flow originates from outside its borders causing increasing water insecurity. Investments in water resource–dependent developments, particularly those with long-term time horizons for return on investment, are constrained by variability in water supply. Upstream damming of the Mekong River in the PRC for hydroelectric power is already affecting flows and sediment deposition in the Mekong Delta. Similarly, intensive hydropower development in Viet Nam is having significant effects on water flow and quality with impacts on agriculture, fisheries, industry, and biodiversity (ICEM 2010). Large-scale deforestation and reduction in forest density for conversion to plantation monoculture impacts evapotranspiration and alters stream flows reducing water availability. Current average annual countrywide water availability is 9,800 m3 per capita, although there are significant regional variations due to local microclimatic and geological conditions. In some basins, demand will exceed supply by 2020 based on current rates of development and water resource projections (ADB 2009b).