Assessment of water requirement changes for upstream development scenarios compared to 2000 baseline conditions

Abstract

     Vietnamese Mekong Delta (VMD) has total land area of about 3.9 million hectares, of which 2.4 million hectares are agricultural lands. The Delta is flat and low with an averaged altitude of about 1 meter. The Delta is considered the granary of the country as it contributes 40% of the national rice product and 85% of the rice export. Located on the downtream of the Mekong, the Delta water resource is affected by upstream developments, especially those increase the use of water from the Mekong. The increased use of water on the upstream results in the reduction of downstream flow that in turn amplifies salt intrusion in the Delta and threatens food safety and security of the whole country. This paper presents results of a study on the change of upstream water requirements under different development scenarios compared to the baseline conditions as of the year 2000. These results can later be used for estimating inflow to the Delta and for calculating water balance for each upstream development scenario.