A SUSTAINABLE SALT REGIME IN THE ISRAELI COASTAL AQUIFER

Water utilization, particularly in dry areas, augments the accumulation of salts in soils and groundwater. This chapter reports a study of the economic aspects of maintaining sustainable salt concentrations in the reservoirs and in water supplied to agriculture and urban consumers. The study has two major purposes, to stress the need to remove salts, an expensive process, and to point to the water sources from which salts should be removed. The analysis is of the Coastal aquifer in Israel and the area above it and on data forecasted for the year 2020. The total amount of salts that can be expected to reach the coastal region in that year is 120,000 tons chlorides; the same quantity has to be removed yearly for a sustainable salt regime to be maintained. A third, perhaps even half, the salts imported to the region will be removed in the natural outflow to the sea or in water exported to other regions, as fresh or recycled water. The rest, tenths of thousands tons per year, will have to be removed actively. The study is done under simplifying assumptions and it should be taken as a first step. A more detailed analysis will incorporate additional hydrological and engineering considerations and perhaps also other sources of contamination. But it seems that the major conclusions, on the need to remove the salts and the efficient way of doing it, will not be modified significantly.