Municipal Wastewater Irrigation Quality and Its Impacts on Selected Soil Properties Around Harar City, Eastern Ethiopia

Abstract

In many arid and semiarid countries, wastewater irrigation is becoming a common practice in agriculture. Commitment of government and social intervention for more effective waste management are the major constraints. The study was conducted in eastern Ethiopia to identify the impacts of municipal wastewater soil physicochemical properties and irrigation water quality. Soil samples were collected from different farm fields to determine the physical and chemical properties of soil, and heavy metal accumulation at different irrigation farms and wastewater samples were also analyzed. Manusipal wastewater taken from different study sites was categorized into three groups: control (nonirrigated), municipal wastewater irrigated farmland and municipal wastewater irrigated farmland. The results showed that bulk density was negatively decreased and moisture contents and total porosity were significantly increased. The soil EC, cadmium, lead available phosphorus, OM, and CEC levels significantly increased with increasing wastewater application. The concentrations of Zn, Cu, Cd, Pb and Cr are highwere higher in irrigated effluent than in nonirrigated effluent. Untreated and treated MWW were tested for heavy metal presence and accumulation. In the present study, soil OM increased as the content in the soil also increased as the number of irrigations increased. The most effective way to eliminate the impact of this municipal wastewater on the soil is to develop and implement an effective wastewater management plan. Limited studies have been done, and they should be encouraged to address municipal wastewater impacts on plants and farmers. The government should be focused on awareness of creation and management systems.