Water scarcity is one of the tricky constraints not in the favor of constant economic development, social sector and natural veracity in the industrialized and unindustrialized country. To minimize water scarcity, utilization of treated wastewater as an alternative technique for irrigation and other purposes by installing wastewater treatment plants to treat the influent comes from the industries. Wastewater reuse has quiet restricted information and consciousness. To change the public behavior towards wastewater reuse, require to educate them, arrange public meetings, seminars and other practices that can easily pull the people mind. So, for this purpose, require to build up a tool which can easily help to policymakers during the consideration of main and significant factors that can manage implementation policies of wastewater reuse. Therefore, purpose and the scope of this work are to develop a system which can easily support the decision for accessing the possibility of implementing reuse of wastewater systems.

When water temperature and irradiance as well as meteorological conditions and nutrient supply are favourable, cyanobacteria can flourish in lakes and rivers where they can produce blooms usually in summer to late autumn, in both subtropical and temperate latitudes. Several of which are toxic and produce specifically hepatotoxins type microcyst ins. Studies undertaken in dams and natural lakes, particularly in the lake Oubeira and the dam Cheffia (East-Algeria), showed that these media evolve quickly to eutrophication, following an increased productivity stimulated continuously by the fertilizer contributions and a change of increasingly dry climate. The appearance of toxic cyanobacteria in these water bodies either used as drinking water or for recreational purposes may present serious health risks for the human population. The biodiversity of toxic cyanobacteria and their toxins, undertaken in the lake Oubeira and the dam Cheffia, showed that the Microcystic is the most implied genus in the formation of cyanobacterial blooms. The concentrations of microcyst ins, estimated by the PP2A method, are very high (28 mg/L) during the period of cyanobacterial blooms in summer and at the beginning of autumn. The MC-LR, MC-YR, and MC-RR are the most common microcyst in congeners identified in these water bodies.