What action caused the Aral Sea’s water levels to fall in the 1960s?

• A. Prolonged drought in the region
• B. Soviets diverted rivers for irrigation projects
• C. Dam construction along tributaries
• D. Industrial pollution in the basin

Answer: (B)

The main concept here is how altering water supply through large-scale irrigation can drastically reduce a body of water’s level. In the 1960s, the Soviet Union redirected major rivers—the Amu Darya and Syr Darya—from feeding the Aral Sea to irrigation for crops like cotton. This greatly cut the freshwater input to the sea. Even if rainfall or local droughts varied, the reduced inflow meant the sea began to shrink because evaporation continued or even increased in the hot, arid basin. Dams and canals were part of the system that redirected water, but the crucial action was diverting river flows away from the sea to support agriculture. As the volume decreased, salinity rose and ecosystems collapsed, illustrating how human water management can transform a large aquatic system.