Assessment of Impacts of Urbanization on Surface Water Quality, The Case of Keha River, Gondar Town

Alemu Amsalu
2018
This study assessed the impacts of urbanization on surface water quality and identify the sources of pollution on Keha River in Gondar town. Urbanization and anthropogenic activities are the key factor causing water quality degradation as we go downstream along Keha River. Based on Keha watershed land use land cover in1999,2004,2006 and 2017, it is shown that there is significant land use change of the bare land, grassland and agricultural land converted into urban land use and Keha River water
more » ... nd Keha River water quality has deteriorate in the past 15 years. The critical source of pollutions are industries like Moha soft drink industry, Gondar hospital, Kedame Gebeya Commercial market, a lot of hotels and restaurants among others. To analyze the river water quality fourteen (14) different strategic sampling sites were selected. The analysis consisted of in situ and laboratory analysis of samples using standard methods. The result indicated that the range of PH (5.9-8.97mg/l), Conductivity (142-1231 us/cm), Turbidity (8-1072 NTU), Dissolved Oxygen (7.4-2.1mg/l), BOD (4.1-217mg/l), TDS (102-1298mg/l), Alkalinity (89-508mg/l), Total Hardness(103283mg/l), Iron(0.15-0.76), Chromium(0.02-0.42), Manganese(0.02-3.9), Phosphate(1.3732.7mg/l), Nitrate(35.4-178mg/l), Total coliform counts(2.9-495) and E.Coli counts (2273.8) for rainy and dry seasons. At all sampling sites except upstream of Keha River the Physico- chemical and bacteriological results of water samples were above the Ethiopian and WHO standard limit indicated that Keha River was polluted. Except upstream of Keha River, at all sites the Dissolved Oxygen (DO) is less than 5 mg/l that is below the WHO and Ethiopian minimum standard limit. High nitrate and phosphate cause of eutrophication, high total coliform and high E.coli lead to water borne disease and the death of the communities especially children because some people like the daily laborers and street children were used for drinking this polluted River within the study area. It is therefore concluded that the river in the s [...]
doi:10.20372/nadre/5472 fatcat:nlfrcgn5fbai3ewuv2gj2elacu