Knowledge Note

"What would it cost to achieve the water-related Sustainable Development Goals?"

Investments in irrigation can have negative impacts on environmental flows and on forests—because of the rebound effect created by higher yields, which increase the expansion of cultivated land—and thus on greenhouse gas emissions and biodiversity. Further, in dry areas, irrigation can lead to maladaptation, whereby farmers drain finite underground water resources or specialize in “thirsty” crops ill-suited for the local climate. Thus, complementary policies are needed to limit the negative impacts on ecosystems and provide farmers with climate-smart practices and technologies.