WASTE-WATER RECLAMATION AND WATER-RESOURCES MANAGEMENT

Wastewater reclamation and reuse are becoming important components of the management of urban, regional and national water resources. Recently, not only countries with chronic water shortage, but also urban areas in temperate climates have considered and implemented wastewater reuse schemes expanding the scope of consumptive uses to include toilet flushing and landscape irrigation, using dual distribution systems and even the reuse as potable waters is being considered and evaluated. Israel is an example of intensive reuse in agricultural irrigation and much experience has been gained in treatment, seasonal reservoirs and establishing quality requirements. The economical justification of wastewater reuse schemes should take into account the overall treatment costs, the 'environmental and health allowances', i.e. the cost of treatment required even when reuse is not practiced, the benefits of water and the savings in conveyance and pumping. The paper also briefly describes the two largest wastewater reclamation projects in Israel, namely: the Kishon Complex Scheme and the Dan Region Scheme, both aimed at unrestricted agricultural irrigation of all crops.