Freshwater competition among agricultural, industrial, and municipal sectors in a water-scarce country. Lessons of Pakistan's fifty-year development of freshwater consumption for other water-scarce countries

Agriculture, industry and municipal water supply compete over scarce freshwater. This study calculated sectoral blue water footprints (WFs) in water scarce Pakistan between 1971 and 2020. Agriculture dominates blue WFs, industry contributed 0.5–1.4%, municipal WFs 0.5–1.7%. Manufacture (cloth and yarn) and electricity production (hydropower) dominated blue industrial WFs. Agricultural crop and livestock production tripled using the same amount of blue water, but industrial and municipal WFs increased with increasing production/population, the blue industrial WF by a factor of 3.3, municipal WFs by a factor of 3.6. Pakistan's water scarcity depends on environmental flow requirement (EFR) definitions. Volumetric government definitions generate low water scarcity allocating almost all water to society. Higher EFR's generate moderate to severe scarcity. Efficient agriculture leaves more water for industry and municipal supply, increasing crop output and decreasing sectoral competition. Policy might support improved water infrastructure. Pakistan's lessons are relevant for other water scarce countries.