## 1 Introduction  
Studies have shown that urban, agricultural, and industrial discharges have a direct effect on surface water quality. Similarly, urban wastewaters cause fecal contamination of surface waters, and urban stormwater runoff, which contains large amounts of fecal microbes, also affects surface water quality [1]. Surface water bodies are vital natural resources that are vulnerable to pollution. The contaminants are chemical, physical, and biological constituents resulting from anthropogenic activities and are of greater environmental consideration [2]. Surface water bodies are extensively used as the major sources for domestic, non-domestic, industrial, and irrigation purposes. Therefore, monitoring and assessment of water bodies is imperative to obtain reliable information on water quality for effective management [3]. Anthropogenic uses of the waterbodies in the study basin can degrade the quality of surface water and impair its usability as potable water supply or for industry, agriculture, recreation, or other purposes. Hence, regular monitoring of water quality of rivers and lake is indispensable [4; 5]. The most affected river stretches are those that flow through urbanized and exceedingly populated urban areas where there is no adequate sanitation. Upstream rural areas are mainly affected by pollutants from non-point sources such as agricultural runoff, whereas urban areas are polluted by point sources, sewage discharges, urban runoff, and pollutants from upstream areas [6; 7]. Studies have shown that some lakes and wetlands around the world have disappeared or are showing changes in their ecosystem. Furthermore, factors such as intensive land use for urbanization and agriculture have had significant impact on the hydrology, ecology, and ecosystem services of lakes, which has eventually led to a decline in lake levels [8]. In addition, pollutants have long been a concern, as their accumulation can have serious effects on fauna, flora, and human health when the huge amount of urban and industrial wastewater reaches the shores [9]. Lake Hawassa is located near the city of Hawassa and is surrounded by agricultural land, industries and residential areas. Therefore, it is susceptible to a variety of pollutants that enter the lake directly or indirectly. On the other hand, the Lake Hawassa Watershed is experiencing rapid land cover change, and natural resources have overwhelmingly diminished. The lake is hydrologically closed and has no apparent outlet, so all pollutants entering the lake are retained. As a result, the lake faces numerous problems, and the water quality deteriorates over time, threatening biodiversity [10]. Significant industrialization, augmented with rapid urbanization and increasing economic development, has increased the extent of pollution [11]. The pollution is mainly from non-point sources caused by urban and agricultural runoff, overgrazing, deforestation, soil erosion, land development, and industrial effluents. This leads to numerous environmental concerns that have resulted in substantial hydrological disturbances. The main factories in the study area are a ceramics factory, a flourmill, a cement products factory, a Moha soft drink factory, a BGI (St. George Brewery factory), an Etabs soap factory, an industrial park in Hawassa, and other small-scale industries. They are virtually all concentrated along the main road, which is close to the shallow swamp, and discharge their effluents into the lake through streams. On the other hand, deforestation and irrigation of the land have caused the drying up of Lake Cheleleka by reducing the streamflow [12]. Various studies have been conducted to examine water quality in the LHW catchment and identify sources of pollution. [PERSON] [11] investigated the eastern catchment of Lake Hawassa Watershed to assess the seasonal water quality and its suitability for the designated uses.