water problem at the system level
Solutions to these challenges are in principle possible and need not be prohibitively expensive. A solution in a particular basin or country would utilize a combination of three fundamental ways to close the demand-supply gap. Two of these are ceteris paribus options and focus on technical improvements, increasing supply and improving water productivity under a constant set of economic activities, while the third is tied to the underlying economic choices a country faces and involves actively reducing withdrawals by changing the set of underlying economic activities. A well-managed sector would identify a sustainable and cost-effective mix of these three solutions.
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Assuring sufficient raw or “upstream” water resources is a precondition for solving other water issues, such as those of clean water supply in municipal and rural systems, wastewater services, and sanitation—the “downstream” water services.