Water Quality Issues in Ethiopia - PDF

Unit 7 Water Quality Issues in Ethiopia 1 Water quality: is a term used to express the suitability of water to sustain various uses or processes Some of the main drivers behind water quality are: Land cover and land use: The type and amount of vegetation, soi...

Unit 7 Water Quality Issues in Ethiopia 1 Water quality: is a term used to express the suitability of water to sustain various uses or processes Some of the main drivers behind water quality are: Land cover and land use: The type and amount of vegetation, soil, and urbanization in a catchment can affect how water flows and how much sediment, nutrients, and pollutants are carried into waterways. Example: forests and wetlands can help filter and retain water, while agricultural and industrial activities can increase runoff and contamination. 2  Climate and rainfall: The amount and intensity of precipitation can affect the quantity and quality of water in a catchment. Examples: heavy rainfall can cause flooding and erosion, which can increase turbidity and suspended solids in water. Droughts can reduce water availability and increase salinity and nutrient concentrations. Climate change can also alter the patterns and variability of rainfall and temperature, which can affect water quality in the long term 3  Catchment geology and topology: The underlying rocks and soils in a catchment can affect the chemistry and mineralogy of water. Examples: limestone and dolomite can increase the hardness and alkalinity of water, while granite and basalt can increase the acidity and iron content. The shape and slope of the land can also affect how water flows and how much energy and erosion it generates. 4  Human activities: The withdrawal, consumption, and discharge of water for various purposes, such as domestic, industrial, agricultural, and recreational, can affect the quality and quantity of water in a catchment. Examples: water withdrawals can reduce the flow and dilution capacity of waterways, while wastewater discharges can introduce contaminants, such as pathogens, metals, organic compounds, and nutrients, into water. Human activities can also alter the natural hydrological cycle and the ecological balance of water systems. 5 Critical Water Quality Issues in Ethiopia: Open defecation: Pollute and contaminate drinking water sources. Major source of fecal-oral transmitted water borne diseases and water based diseases, common in urban and rural part of Ethiopia. Sewage discharges: Direct liquid discharge into freshwater bodies (sewerage coverage of Addis Ababa City is less than 10 %) Industrial discharges: Unregulated discharge from industries: textile industry, tanneries, breweries, food processing plants, coffee processing industries, chemical manufacturers and paint factories Solid waste disposal: Open dumping and improper landfill site selection adversely affect both surface and groundwater 6  Urban runoff: Runoff from urban surfaces could damage and contaminate protected water supply sources. Agricultural applications: Pesticides and fertilizer applications are the major concern from water quality deterioration.  Nitrogen and phosphate fertilizers end up in water bodies and result in eutrophication. Hydrologic modification: Deforestation for agricultural land, wetlands to agricultural land conversion, removal of riparian vegetation, stream bank modification and channelization of tributaries affects the physical, chemical and biological qualities of water. 7  Resource extraction: Mining, runoff from mine tailing sites could affect water quality Lake and dam pollution: Eutrophication 8 Water hyacinth, siltation and nutrient enrichment 9 Textile wastewater discharges 10 Water quality monitoring Water quality monitoring systems are the processes and activities that measure and assess the physical, chemical, and biological characteristics of water sources and water supply systems in the country. Water quality monitoring systems are essential for ensuring the safety, reliability, and sustainability of drinking water protecting the environment and public health. Water quality monitoring systems in Ethiopia face various challenges, such as lack of adequate resources, capacity, coordination, data management. 11 T E h n e d 12 Quiz 6 (5 pts) Instruction: Answer the following questions in short 1. ___________is water that is added to an industrial water system to replace water lost through processes such as evaporation, leaks, or steam production. (1 pt) 2. ------------------- and --------------------- can increase the hardness and alkalinity of water. (2 pts) 3. ------------------ and --------------------- can increase the acidity and iron content of water. (2 pts) 13