Water is one of the most essential natural resource known in the world, covers around 80 percent of the earth’s surface and it is elixir of life without water life is not possible and it represents a fundamental requirement for all life activities and it is essential to human, plants and animals, but only small portion of the water in the world is available to manage human use (WHO; Anunan, et al., 1993).
Supply of water is among the most essential requisites for continuity of living things. Water supply plays an important role in both social and economic development of a people and the availability and accessibility of adequate water supply with safe quality is the basic thing for improvement of public health, better living standard and economic development (Hofkes 1998, cited Yitayh, 2011). Access to safe, clean and adequate water is a universal need and a basic human right, but majority of the world’s population or nearly a billion people living in the developed world does not have access to adequate and safe water and people might be forced to use unsafe water for drinking and other domestic purpose. According to the world health organization more than 80 percent of the disease in the world are associated with unsafe drinking water (Woreda, 2018).
In general the water supply coverage in towns of developing countries and African towns in particular is relatively lower while compared to the water demand (WHO and UNICEF, 2010). This problem is also true for Ethiopian towns like Arba-minch.
River water is the water that available on the surface play a vital in providing water resource for various purposes such as, for human, ecosystem survival and health. River encompass the most important water resources for irrigation, industrial use and domestic water supply and other purposes in a watershed. So the tends to simulate serious hygienic and ecological problems (Choo, 2015).
Most of the quality of urban river water is might be affected by many biological, chemical and physical parameters introduced by means of human (anthropogenic) activities, development of agricultural and livestock activities along the river and natural force (Mophin-Kani and Murugesan, 2011). Generally, land use change contributes to increase pollutants through the agricultural runoff, sediment transport (erosion) in to the river and it makes the quality of water undesirable for domestic purpose. Water quality is managed by setting water quality standards, criteria’s and related legislation Water quality criteria, standards and related legislations to achieve the customer’s requirement.
Nowadays, Water quality is an issue of major concern given the scarcity of freshwater resources throughout the world, because around 80 % of disease caused health problems associated with provision of availability of unsafe water (WHO, 2004; Ibrahim et al., 2014). According to CSA (2004) providing unsafe water is the major cause of water-borne diseases in most developing countries, including Ethiopia. Unavailability of adequate, safe, and affordable water seriously affects health, social, and economic conditions of people (Yitayh, 2011).
Water quality is the measure of how good or bad the water is, in terms of supporting beneficial uses and meeting its environmental standards. Water is safe for drinking if and only if biological, chemical and physical characteristics that meet WHO guidelines or national standards on drinking water quality (Benignos, 2012).
The quality of ground and surface water is determined in terms of its physico-chemical and biological characteristics, since the physico-chemical and biological parameters indicates the quality of water (A. Loukas, 2010). The water quality of rivers is characterized by high level of heterogeneity in space and time, due to the distinction of cover land around. Water treatment is the most mechanism of converting unsafe raw water into safe drinking water and other uses or it involves physical, chemical and biological processes that transform raw water into drinking water (Kriti & Smita, 2013).
Surface water without treatment can’t be used as municipal drinking water, because surface water may contain high concentration of natural organic matter and other substances which can be harmful for public health and can form intolerable reaction or biological growth in the systems (Hamel et al., 2007). Therefore, water treatment is necessary to treat or purify water the raw water impurities and make the water suitable for human consumption through the removal and killing of pathogens, tastes, smell and other undesirable physical and chemical constituents and the treatment process may be arranged in a treatment sequence.
Kulfo River is one of the River basin in southern rift valley in which human activities associated with industrial, rapid urbanization and agricultural activities might be the main source of water pollution or contamination. Range of the water quality variations in the river depends on the percentage of change in land use. Therefore, the land use activities in the river basin must be carefully planned and controlled on account of protecting water resource and water quality status.\nKulfo river basin, covering the western part of Arbaminch, some of the people in the local areas used the river water for different purposes such as, household, industrial, agricultural and other purposes making it a crowded river basin in Arbaminch. Therefore, water quality of the river will be changed from time to time due to human activities and it needs to assess the quality of the water and will propose the treatment process will required to make the potable and palatable water to providing of safe and adequate water for Limat Kebelle.