Abstract:
ABSTRACT
Background: Despite the day today increasing of river pollution due to anthropogenic
activity in Gondar like some other cities in Ethiopia, little information is available about the
present situation of rivers.
Objective: Therefore this study was assessing the physicochemical and bacteriological
parameters status of Megech, Shinta, Lesser Angereb (Keha), and Demanza Rivers in
Gondar, Ethiopia from January to April 2019.
Method: The water samples were collected from twelve different sampling points which
were selected based on anthropogenic interference along the aforementioned four rivers after
reconnaissance was done. From each sampling point three samples were collected per month
for three consecutive months i.e. January, February and March. Over all 108 river water
samples 24 waste waters sampling were collected. These samples were subjected to
bacteriological analysis, i.e. Total coli form count and faecal coliform count by using
membrane filtration method. The physicochemical analysis of the water samples includes
pH, temperature, electrical conductivity, total dissolved solids (TDS), dissolved oxygen
(DO), turbidity, nitrate, chloride, nitrite, calcium, magnesium, sulphate, phosphate by using
spectrophotometer as well as heavy metals like copper, iron, zinc, manganese and lead by
using atomic absorption spectroscopy (AAS).
Result: Among the 21 studied river water quality parameters: electrical conductivity (413 to
2470?s/cm), turbidity (0.8 to151 NTU), total dissolved solids (201 to 1214mg/l), ph (4.75 to
8.0), and temperature (14.5 to 29.8 °C), The observed value of major ions and nutrients on
water samples of Megech River and its tributaries: i.e. Chloride, sulphate, calcium,
magnesium, nitrate, nitrite, ammonia and phosphate was1.2 to 39 mg/l, 3 to 69mg/l, 28 to
109mg/l, 24 to 70mg/l, 0.88 to 79.2mg/l, 0.012 to 2.4mg/l and 0.25 to 11.6 mg/l were
respectively.
Conclusion: The high levels of fecal and total coliforms are often associated with disease
causing microorganism such as bacteria and other parasites, so that consuming this water
source may cause water borne diseases. The increasing values of other parameters of certain
contaminants also indicate that the study River water will be unsafe for domestic purposes
without some form of treatments. Excess nutrients and heavy metals in drinking water can be
toxic to humans and requiring costly treatment of water for human consumption. Again,
excess nutrients in water bodies enhances algal growth and causes expansion aquatic invasive
species
