The restoration of the Mesopotamian marshlands : Optimal water allocations to agriculture, marshland and navigation

This paper provides a decision support system, which embodies the highest possible level of analytical details about the essential features characterising the Southern Iraqi ecosystem, and which is suitable to use by the Ministry of Water Resources in deciding whether, and under which conditions, to restore marshlands in order to maximise the social welfare of the Iraqi general population. A production function approach has been adopted to evaluate impacts of water allocated to agriculture. An economic efficiency criterion has been implemented in order to assess direct and indirect benefits from wetland expansion, while option and existence benefits from wetland restoration have been assessed by applying a double bounded dichotomous choice econometric model to a dataset arising from face-to-face interviews of Iraqi people living in agricultural villages, cities and marshland villages. A replacement cost approach has been adopted to evaluate impacts of water allocated to navigation. The numerical maximisation of the overall social welfare function shows that it is sustainable and desirable to expand Mesopotamian marshlands up to one third of the maximum extension, with the agriculture being maintained at its status quo and the long-run navigation project being implemented.