Why is irrigation important for rice farming in the Mekong basin?

Irrigation is essential for rice farming in the Mekong basin because the region experiences a long dry season, lasting from November until May, during which rice cultivation is impossible without supplemental water.1

Under normal conditions, rain-fed lowlands and upland areas relying on wet-season precipitation can only support a single crop per year. Irrigation transforms this agricultural capacity in several ways:2

• Multiple Harvests: By storing water during the wet season, farmers can use it to produce a second or even a third crop throughout the year.2
• Flood Management: Irrigation systems, when combined with flood control, protect cultivable land by reducing the delays and crop losses typically caused by floodwaters overflowing the river’s banks.2
• Economic Productivity: Water management allows for more consistent agricultural output, which is vital to the economy of the lower basin.21

While the Irrawaddy River also supports irrigation in its own basin, the Mekong’s specific hydrological cycle—driven by seasonal monsoon winds—makes irrigation the primary factor in overcoming the limitations of the dry season.13