Agriculture, water and the environment: future challenges

Various countries in the Mediterranean Basin and other arid and semi-arid regions are facing a gap between water supply and demand. This gap is closely linked with agricultural production and environmental issues. It is probably due to small amounts of precipitation and low availability of natural water sources. Special ventures have to be undertaken in order to supply water at adequate quality for all requirements. These can be accomplished by development of additional water sources that currently are considered marginal. The additional sources include saline ground water, treated wastewater and runoff water and are usually required to augment the limited supply from the regional conventional high quality local sources. The paper presented options for development of the marginal water sources in arid zones in conjunction with minimizing the dependence on high quality water. Domestic secondary effluent is a valuable water source for reclamation however, additional treatment is required to use it for unrestricted purposes. It can be achieved primarily by implementation of the membrane technology, namely ultrafiltration (UF) and reverse osmosis (RO) stages.