wastewater can be considered as both a resource and a problem. Wastewater and its
nutrient content can be used extensively for irrigation and other ecosystem services. Its reuse can
deliver positive benefits to the farming community, society, and municipalities. However,
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wastewater reuse also exacts negative externality effects on humans and ecological systems, which
need to be identified and assessed.
Before one can endorse wastewater irrigation as a means of increasing water supply for
agriculture, a thorough analysis must be undertaken from an economic perspective as well. In
this regard the comprehensive costs and benefits of such wastewater reuse should be evaluated.
Conventional cost benefit analysis quite often fails to quantify and monetize externalities associated
with wastewater reuse. Hence, environmental valuation techniques and other related tools should
be employed to guide decision-making. Moreover, the economic effects of wastewater irrigation
need to be evaluated not only from the social, economic, and ecological standpoint, but also from
the sustainable development perspective.
Pakistan is a case which illustrates this problem. Both treated and untreated municipal
wastewater in the vicinity of large cities like Faisalabad is used for vegetable production. But,
how safe is this practice? How does one tradeoff between the obvious benefits of this use and
the costs associated with i