noun
irrigation water
Water supplied for agricultural irrigation, typically via canals or pipes.
この地域では、灌漑用水が不足している。
In this region, irrigation water is in short supply.
農家は川から灌漑用水を引いている。
Farmers draw irrigation water from the river.
農業用水 is a broader term for agricultural water, which may include water for livestock or washing, while 灌漑用水 specifically refers to water for irrigating crops.
Compound of 灌漑 (irrigation) and 用水 (water for a specific use). The kanji 灌 means 'to pour' or 'to irrigate', and 漑 also means 'to irrigate'. 用水 is a common suffix for water used for a particular purpose.