نمک زدایی یا انحراف؟ مقادیر غیر بازار ساحلی به عنوان یک ابزار تصمیم گیری برای سیاست های مدیریت یکپارچه آب : مورد حوضه رود اردن

This paper deals with a cost effective analysis of two options to increase the water supply in Israel. The first policy is to divert 300 Million Cubic Meters (MCM) of water from the Sea of Galilee (SOG) to the central part of Israel. This policy is the existing one. The second policy is to replace this diversion with desalinated water plants that will be built on the Mediterranean Coast (MC). These two options carry both market and non-market consequences. The first policy has a negative effect on the SOG itself due to the lower lake level. It also carries some negative consequences on the Jordan River (JR) and the Dead Sea (DS) which are located downstream. The second policy involves water production at a higher cost and has negative external effects of scarce coastal land usage and high energy consumption. A Payment Card (PC) Contingent Valuation (CV) survey was performed at the four sites (the SOG, the DS, the JR and the MS). We show that when one takes these non-use values into account, the preferred solution will shift from the usage of the SOG to the desalination policy.

Water resources are essential for household, farming and industrial uses. Projected demand, especially in the household sector, will worsen the existing water problems worldwide (Afgan et al., 1998). Therefore, water use should be planned in a rational way in order to account for all uses and allocate water where the marginal contribution is the highest. This should be done by taking into account both market as well as non-market values of the water resources (Mitchell and Carson, 1989; Loomis, 2005). After counting out approximately 99% of the available water on earth (too saline or stored in icebergs), even the remaining 1% is not equally distributed. Therefore, while observing high rainfall areas, we also observe semi-arid as well as arid regions. Desalination is one of the proposed solutions to alleviate the increasing demand vs. supply gap in such semi-arid and arid regions.

For many years, Israel has used the SOG's water for agricultural and domestic uses. This ongoing policy led to two major implications, a negative effect on the SOG due to the lowering of its water level as well as negative impacts on the JR and the DS which are located downstream. This impact was a major concern from a touristic and heritage perspective. This article examines the overall expected impact of discontinuing the diversion of the SOG's water and replacing it with desalinated seawater. This analysis includes for the first time the non-market values of the four sites (the SOG, the DS, the JR and the MS). By providing such an analysis we comply with Ledoux and Turner (2002) and Pendelton et al. (2007) arguments about the insufficient environmental values in the decision making process.