Browsing by Author "Eliakimu, Naziel"

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    Water quality in earthen dams and potential health impacts: case of Nadosoito Dam, Tanzania
    (IWA Publishing, 2018-09-01) Eliakimu, Naziel; Machunda, Revocatus; Njau, Karoli;
    The aim of the study was to assess seasonal water quality variations in an earthen dam and their potential impact on the health of those using the water for domestic purposes. High values of chemical oxygen demand, from <0.7 to 87 mg/l, and turbidity, from 204 to 53,300 NTU, were reported. Turbidity and total suspended solids were the highest at the onset of rainfall, and generally declined from the wet to the dry season. Ammonia concentrations ranged from 0.14 to 270 mg/l and nitrate from 0.6 to 1,715 mg-N/l, and were highest towards the end of wet season, while NO2-N was highest (290 mg/l) in the dry season. There were some notably high phycocyanin (PC) pigment values (19.9 to 495 μg/l) unique to cyanobacteria, well above the WHO alert level of 30 μg/l. PC is associated with a variety of toxins affecting humans and animals. Possible sources of pollutants include animal droppings/urine and runoff from farms applying fertilisers. A further aim was to assess water treatability with a pilot inclined plate settler system for pollutants and microbial removal. The results of this study suggest that water treatment systems must be designed to take care of the worst influent water quality conditions.
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    Water quality variation and pollutants transformation in the Nadosoito dam of Arkatani village, Monduli district
    (NM-AIST, 2019-02) Eliakimu, Naziel
    The study aimed at assessing seasonal dynamics of water quality parameters, transformation of selected pollutants and seasonal diversity of selected microorganisms (Cyanobacteria) in Nadosoito dam of Arkatani Village, Monduli district, Arusha Tanzania. The study aimed at establishing the treatability of the dam water using Inclined Plate Settler (IPS) coupled with settling tank and a constructed wetland, from January to September 2017 capturing the wet months and the driest month. Analysis was carried out as per standard methods for the examination of water and wastewater (APHA 2012). High values of COD, from <0.7 to 87 mg/l, and turbidity, from 204 to 53 300 NTU, were recorded. Turbidity and TSS were highest at the onset of rainfall, and generally declined from the wet to the dry season. The highest levels for both were due to loading materials into the dam. Ammonia concentrations ranged from 0.14 to 270 mg/l and nitrate-nitrogen from 0.6 to 1715 mg/l; they were highest towards the end of wet season in april, while NO2-N was highest (290 mg/l) in the dry season (September). There was a notably high value of Phycocyanin (PC) pigment (19.85 to 495 μg/l) unique to cyanobacteria, well above the WHO alert level of 30 μg/l. PC is associated with a variety of toxins affecting humans and animals. Possible sources of pollutants include; animals’ droppings/urine and runoff from farms applying fertilisers. The results of this study suggest that water treatment systems must be designed to take care of the worst influent water quality conditions.