This paper provides an overview of the issues in and approaches to measuring and enhancing the value of agricultural water
in large irrigated river basins. It develops a framework and a set of indicators for valuing agricultural water by looking
into various dimensions and underlying key factors that influence the value of water at micro, meso and macro levels. The
indicators are applied to recent, primary- and secondary-level empirical data from the Indus basin Irrigation system of Pakistan.
In addition, the paper compiles recent estimates of the value of agricultural water from 40 settings in 23 countries. Finally,
the paper outlines measures for enhancing the value of agricultural water. The paper makes four main points: (1) The popular
productivity indicators based on crop output do not capture the full range of benefits and costs associated with agricultural
water use. (2) The value of agricultural water may not be as low as it is generally perceived or estimated when all major
uses and direct and indirect benefits of water at various levels are properly accounted for. (3) The value of water varies
across time and space, and the value to stakeholders at various scales (farmer, system manager, basin planner and national
policy maker) could be quite different. For example, the estimate of agricultural water value in the upper Indus basin in
Pakistan varies from US
0.04/m < sup > 3 < /sup > at the farm scale to US0.04/m3 at the farm scale to US0.22/m
3 at the national scale. The farm-scale value is more relevant, e.g., for agricultural water charging policies, but for water-sector
investments and allocation decisions, the national-scale value is important. The decision-making processes related to water
sector investments, allocations, management, and charging/cost recovery schemes could be potentially misguided if key dimensions
of water value that are related to water availability and use, benefits/costs, and temporal and spatial aspects are not properly
accounted for in valuation. (4) Efforts should be directed not only at increasing the productivity of water in terms of mass
of output per unit of water, but also the overall benefits or value of water at various levels for larger growth and poverty
alleviation impacts, considering the sustainability of the systems.
Communicated by R. Evans.