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quantity or volume of water
雨が少なく川の水量が減った。
Rainfall was scarce and the river's water level dropped.
ダムの水量を管理して洪水を防いだ。
They managed the reservoir's water level to prevent flooding.
水量が豊富な山岳地帯では水力発電が盛んだ。
Hydroelectric power generation thrives in mountainous areas with abundant water.