Contamination of Stream Sediment With Heavy Metals in the Awetu Watershed of Southwestern Ethiopia

Surface sediment samples were collected from different streams of Awetu Watershed in southwestern Ethiopia. Sediment analyzed for As, Cd, Cr, Pb, and Hg levels using inductively coupled plasma optical emission spectrometry. The heavy metal concentration ranged 183.60 to 1,102.80 mg/kg As (mean 623.32 ± 291.65 mg/kg), 4.40–303.20 Cd (151.09 111.5 149.20–807.20 Cr (375 212.03 485.60–3,748.80 Pb (2005.94 954.99 mg/kg) 3.6–5.6 (4.64 0.59 mg/kg). mean the followed decreasing order > Hg. are detected at high concentrations with values 623.32, 375.00, 2,005.94 respectively. A low level (3.6 was recorded contamination factor (CF) all studied metals a degree (CF < 1) very ≤ 6). Mainly, Dololo Kito show 6) than Boye streams. Specifically, have significantly elevated others. Geo-accumulation index (Igeo) shows moderate Hg; uncontaminated heavily contaminated by Cr; extreme Cd. Untreated solid waste, garages farmlands sources contamination. Streams receiving wastewater effluents teaching institutions had higher concentrations. Dumping electronic wastes car washing discharges also identified as another source pollution.