Abstract:
The Gidabo River and its tributaries are the main sources of water for more than 1,584,646 inhabitants. It is an important source of water for the surrounding rural communities for various uses such as domestic, irrigation, livestock watering, fishing, and recreation. The river is the main tributary of Lake Abaya. The present study was designed to investigate the water quality status of the Gidabo River and its tributaries for domestic and aquatic life. To assess the water quality status, water samples were collected in monthly intervals for a period of 3 months from September to November (coffee processing time), 2022. Arc GIS 9.3, 3 DEM, and spreadsheet were used to analyze the data collected from SRTM (Shuttle Radar Thematic Mapper, 90 m) and field observation. Of all the water quality parameters analyzed; turbidity, BOD5, DO, COD, pH, Ni, Fe, NO3 -, and PO4 3- were higher than the recommended limits of national and international standards for aquatic life. Based on the Weighted Arithmetic Mean (WAM), Water Quality Index (WQI) calculations of the River, WQI value of the river ranges between 34.83 and 54.31 in different reaches of the watershed which is classified under bad category. The wet coffee processing industry which is the main sources of contamination in the watershed uses 63 L of processing water to produce 1 kg of green coffee beans. Traditional lagoons, with an average hydraulic retention time (HRT) of 1.99 days, are the most common methods of treating wastewater. The river is at higher risk from harmful anthropogenic activities in the watershed and requires urgent monitoring and mitigation to prevent further degradation.
摘要:
Gidabo河及其支流是1,584,646多名居民的主要水源。它是周围农村社区的重要水源,用于各种用途,如家庭,灌溉,牲畜浇水,钓鱼,和娱乐。这条河是阿巴亚湖的主要支流。本研究旨在调查Gidabo河及其支流对家庭和水生生物的水质状况。为了评估水质状况,从9月到11月(咖啡处理时间),每月一次收集水样,为期3个月,2022年。ArcGIS9.3,3DEM,和电子表格用于分析从SRTM(航天飞机雷达专题映射器,90μm)和野外观测。在所有分析的水质参数中;浊度,BOD5,DO,COD,CODpH值,Ni,Fe,NO3-,和PO43-高于国家和国际水生生物标准的建议限值。基于加权算术平均值(WAM),河流水质指数(WQI)计算,在流域的不同河段,河流的WQI值在34.83和54.31之间,被归类为不良类别。作为流域主要污染源的湿咖啡加工业使用63L的处理水来生产1kg的绿咖啡豆。传统的泻湖,平均水力停留时间(HRT)为1.99天,是最常见的废水处理方法。该河流面临流域有害的人为活动的高风险,需要紧急监测和缓解,以防止进一步退化。