MEKELLE UNIVERSITY

ETHIOPIAN INSTITUTE OF TECHNOLOGY (EIT-M)

SCHOOL OF CIVIL ENGINEERING

AN ASSESSMENT OF WATER QUALITY IN MEKELLE CITYCASE STUDY GEREB

SEGEN

A Thesis Proposal Submitted In Partial Fulfilment of the Requirement for the

Master of Science Degree in Environmental and Sustainable Infrastructure
Engineering

BY

NIGUS HALEFOM

ID NO: - EITM /PR 176275/12

ADVISOR: SOLOMON TSEGAY (PH.D.)

CO -ADVISOR: TESFAY TSEGAY (M.Sc.)

November 29, 2023

ABSTRACT

Water is an essential requirement of human life and activities associated with industry,
agriculture, and others, and it is one of the most delicate parts of the environment. The quality of
water is usually described according to its physical, chemical and biological
characteristics.despite concerted efforts; mekelle is suffering in water quality. The infiltration of
water through Calcium and magnesium rich soil, unwise use of chemical fertilizers and
pesticides in agriculture are causing deterioration of water quality.

The main objective of proposal of gereb segen is to assessment of water quality in the influent
and effluent of water. This will be done through serious sampling of water quality in difference
seasons and analysis will done in situ and in laboratory. It is therefore necessary to check the
water quality through ES withWHO at regular interval of time.

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TABLE OF CONTENTS

ABSTRACT................................................................................................................................................... i
TABLE OF CONTENTS .............................................................................................................................. ii
LIST OF FIGURE........................................................................................................................................ iii
LIST OF TABLES ....................................................................................................................................... iii
LIST OF ABBREVATIONS ....................................................................................................................... iv
1. INTRODUCTION............................................................................................................................... 1
1.1. Background ................................................................................................................................. 1
1.2. Statement of Problem ................................................................................................................. 2
1.3. Objectives ..................................................................................................................................... 2
1.3.1. General Objective ............................................................................................................... 2
1.3.2. Specific objective .................................................................................................................. 2
2. LITERATURE REVIEW................................................................................................................... 3
3. MATERIALS AND METHOD ............................................................................................................ 5
3.1. Location of study area ................................................................................................................ 5
3.2. Materials to be used .................................................................................................................... 5
3.3. Methods to be used...................................................................................................................... 7
4. Expected output ................................................................................................................................ 10
5. Schedule ............................................................................................................................................. 11
5.1. Budget ........................................................................................................................................ 12
References .................................................................................................................................................. 13

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LIST OF FIGURE
Figure 1 water treatment unit Source: (Michigan State University, East Lansing, USA) ............. 4
Figure 2 Picture of gereb segen reservoir (Source: internet) .......................................................... 5

LIST OF TABLES

Table 3-1 Water quality standard on selected parameters .............................................................. 9

Table 5-1 Activity Schedule ......................................................................................................... 11
Table 5-2 estimated budget ........................................................................................................... 12

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LIST OF ABBREVATIONS

WQ Water Quality

DO Dissolved Oxygen

COD Chemical Oxygen Demand

BOD Biological Oxygen Demand

NTU Nephlometric Turbidity Unit

TDS Total Dissolved Solid

E.C Electrical Conductivity

WQS Water Quality Standard

TSS Total Suspended Solid

CRM Certified Reference Material

WHO World Health Organization

ES Ethiopian standard

WQI water quality index

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 1. INTRODUCTION
1.1. Background

The quality of drinking water has a powerful Impact on public health and therefore
effectiveMonitoring and comprehensive assessment of public drinking water supply systems are
crucial to protect the Wellbeing of the public and to allow implementation of a preventive
approach to manage drinking water quality. (1)

Water is an essential requirement of human life and activities associated with industry,
agriculture, and others, and it considers one of the most delicate parts of the environment. In the
last few decades, the accelerated pace of industrial development and progressive growth of
population caused in tremendous increase in the demand of fresh water. The quality of surface
and ground water is identified in terms of its physical, chemical, and biological parameters. (2)

Study of surface water pollution of the river is important due to effluents from municipal sewage,
livestock wastewater, industries, agricultural activities, and urban runoff which discharge into the
river resulting in extensive variations in the water quality.

Water quality status is generally affected by many physical, chemical and biological parameters
introduced by natural forces and human (anthropogenic) activities. Water quality criteria,
standards and related legislation are often used as the main administrative means to manage
water quality status in order to achieve user requirements. Water quality standards for surface
water vary significantly due to different environmental conditions, ecosystems and intended
human uses. Different uses of water raises different concerns and therefore different standards
must be considered. The most common national requirements for drinking water of suitable
quality for many countries are based on the standards of the World Health Organization
guidelines for drinking water. (2)

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 1.2. Statement of Problem

Water pollution is the contamination of water bodies that occur when pollutant are indirectly or
directly discharge into water bodies without adequate treatment to remove the impurities. It will
give an affect to ecosystem and human life and become an issue nowadays.

Supplying of safe drinking water has been a big challenge for mekelle city. The quality of water
is affected by natural and anthropogenic activities either physical or chemical changes to the
quality of water. This physical and chemical water quality changes makes unsuitable for drinking
water.

The water quality of gereb segen (May gab at) needs to be studied comprehensively because of
the area’s importance as a drinking water supply mekelle City. Therefore, water quality should
be ensured that no parameters exceeds that would affect human health. Especially chemical
constituents to cause adverse health effects after prolonged periods of exposure..

1.3. Objectives
1.3.1. General Objective
The overall objective of this proposal is water quality assessment of gereb segen (May gab at),
compared with WHO and Ethiopians drinking water guide lines,
1.3.2. Specific objective
 To compare and contrast the concentration of the three water quality parameters
with WHO and Ethiopians drinking water guide lines,
 To characterize the source(influent) in the dry season and in the rainy season of
the study area based on three water quality parameters (e.g. physical, chemical,
and biological
 To characterize the (effluent)in the dry season and in the rainy season of the study
area based on three water quality parameters (e.g. physical, chemical, and
biological parameters
 Efficiency of each unit of the water treatment plant
 To provide water quality information to support for water quality monitoring
activates.

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 2. LITERATURE REVIEW
The physical, chemical, biological and aesthetic property of water is the parameters used to
describe its quality and determine its capability for a variety of uses including the protection of
human health and the aquatic ecosystem. Most of these properties are influenced by constituents
that are either dissolved or suspended in water and water quality can be influenced by both
natural processes and human activities.(3)

Water quality is a complex subject, which involves physical, chemical, hydrological and
biological characteristics of water and their complex and delicate relations. From the user's point
of view, the term "water quality" is defined as "those physical, chemical or biological
characteristics of water by which the user evaluates the acceptability of water". For example for
drinking water should be pure, wholesome, and potable. Similarly, for irrigation dissolved solids
and toxicants are important, for outdoor bathing pathogens are important and water quality is
controlled accordingly. Textiles, paper, brewing, and dozens of other industries using water,
have their specific water quality needs.

Water quality index is very important for surface water resource especially lakes. Comprising of
three seasons summer winter and raining seasons. The calculated WQI for various studied lakes
showed fair water quality in monsoon season which then changed to medium in winter and poor for
summer season.(4)

Various technical papers on Assessment of water quality for lake have been presented at research
level from which I referred many papers for study. These papers are presented below.

For the assessment of water pollution status of the water bodies, the following water quality
parameters will analyze: pH, electrical conductivity, Temperature, Total dissolved solid, Total
Solids, Total Alkalinity, Dissolved oxygen, Chemical oxygen demand, Biochemical oxygen
demand, Total Hardness etc.

Analytical grade chemicals will used for preparing all reagents and solutions. Distilled water will
used in all experiments. Before each analysis, all instruments are calibrated according to
manufacturer’s recommendations.

For surface water treatment it starts from screening of large floating debris and the followed by
aeration to increase oxygen content and to remove iron and manganese.

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Generally for surface water the treatment process is Screening, aeration, plain sedimentation,
coagulation, sedimentation, filtration, and pre and post chlorination.

Figure 1 water treatment unit Source: (Michigan State University, East Lansing, USA)
WATER-QUALITY CRITERIA

Water-quality criteria generally describe the quality of water needed to protect and maintain
individual water uses. They are based on parameters that describe the quality of water.

Water-quality criteria set a maximum level for the concentration of a substance in water which is
not harmful under the conditions of a continuous water use for a single, specific purpose, such as
water for drinking-water supply, agriculture and recreation, and requirements of biological
communities and the functioning of aquatic ecosystems in general.

The primary purpose of the Guidelines for drinking-water quality is the protection of public
health. The Guidelines provide the recommendations of the World Health Organization (WHO)
for managing the risk from hazards that may compromise the safety of drinking-water.(5)

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 3. MATERIALS AND METHOD
3.1. Location of study area

Gereb Segen is asurface water reservoir located in the Hintalo Wajirat woreda of the Tigray
Region in Ethiopia. The reservoir was built in 2000 by SAERT.Currently the mekelle city
administration is supplementing the city’s water supply from gereb segen earth dam, located
south west of mekelle. The dam was initially designed for irrigation however, later on it was
decided to be water supply reservoir. The dam has height of 45 m and a storage c capacity more
than 12Mm3 with a treatment plant capacity of 15,000m3 per day.

Figure 2 Picture of gereb segen reservoir (Source: internet)

3.2. Materials to be used

The following equipment’s are used for water quality laboratory examination in the spot and on
water quality lab:

 sampler  TDS meter  BOD bottle

 ph. meter  conductivity meter  Wash bottle
 digital temperature  turbidity meter  Oven dry
 DO meter  electronic balance  Forceps
 Universal incubator  String rod
 Colony counter  Different Reagents
 Spoon  Palin test tablet
 Paper towel
 Palintestphotometer

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Data to be collected
The following are the sources for the primary data to be used in water quality analysis

1. Physical parameter: temperature, turbidity, total suspended solid, Ph total dissolved solid,
electrical conductivity

2. Chemical parameter: concentration of heavy metal, concentration of trace constituent

3. Biological analysis: total coliform and thermo tolerant or E.Colli.

Water quality characteristics

Water quality is determined by physical, chemical and microbiological properties of water.

These water quality characteristics throughout the world are characterized with wide
variability. Therefore the quality of natural water sources used for different purposes should
be established in Physical characteristic of water: Physical characteristics of water
(temperature, color, taste odor and etc.) are determined by senses of touch, sight, smell and
taste. For example temperature by touch, color, floating debris, turbidity and suspended solids
by sight, and taste and odor by smell.

Chemical characteristic of water: The chemical characteristics of natural water are a

reflection of the soils and rocks with which the water has been in contact. In addition,
agricultural and urban runoff and municipal and industrial treated wastewater impact the
water quality. Microbial and chemical transformations also affect the chemical characteristics
of water.

Microbial characteristic: The principal groups of microorganisms in natural water include

protists, plants and animals. Some of the physical and biological characteristics of organisms
important for water quality.

3.3. Methods to be used

Sampling Methods and Analytical Procedures
Water samples will collect with 1-L plastic containers, which were pre-rinsed with distilled
water to avoid an unpredicted change in the characteristic of the water samples.

The collected samples will brought to the laboratory for the estimation of various chemical
and biological parameters as per the procedures given in the standard methods.

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Water sampling will be conducted twice in rainy season and dry season of influent and
effluent water. Preservation and transportation of the water sample to the laboratory will
perform according to standard methods.(matias bonansea, 2015).in Situ WT, pH, DO, EC,
will measure using portable instruments.Secchi disk transparency(SDT)will measured
turbidity using 20cm diameter Secchi disk with alternate black and white quadrant.in the
laboratory chemical and biological analysis will be done.. Following collection and during
transportation, samples should be kept at 4oc. Samples requiring preservation should be
preserved as soon as possible after collection to maintain the integrity of the sample. If
immediate analysis is not possible, storage at 4oC is recommended for most samples.

Sample labeling

Information on the sample container or the tag should include:

• sample code number (identifying location)

• Date and time of sampling

• Source and type of sample

• Sampler’s name

In addition to proper labeling before measuring the sample equipment should be calibrated
using CRM.

Water quality standard

Water quality standard can be used to define the designated beneficial use of water be
defining water quality that is needed to support those uses. The minimum beneficial uses to
be considered in order to establish the standards which are assigned different purposes; for
example, drinking water supplies, recreation, agricultural uses, industrial uses, and
navigation. Moreover, a requirement specifies the standards have to protect public health and
welfare. The water quality standard for drinking which is reported by Ethiopian and WHO on
selected parameters is shown below in table.

The World Health Organization produces international norms on water quality and human
health in the form of guidelines that are used as the basis for regulation and standard setting,
in developing and developed countries worldwide. As shown in the table 3-1:- water quality
standard on selected parameters.

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Table 3.1 Water quality standard on selected parameters

Parameters Value
Ethiopian WHO unit
Physical parameters

Ph 6.5-8.5 6.5-8.5 pH
O
Temperature 25 25 C
TDS <1000 1000 Ppm
Turbidity <5 5 NTU
electrical conductivity <1500 µs/cm
dissolved oxygen >5 Ppm
TSS - -
Chemical parameters
Sodium 200 Ppm
Calcium 75 Ppm
Magnesium 50 200 Ppm
Chloride 250 Ppm
Total Hardness 300 - mg/l CaCO3
Total Alkalinity 200 500 Ppm
Fluoride 1.5 1.5 Ppm
Nitrate 50 45 Ppm
Nitrite 3 2 Ppm
Chromium 0.05 0.05 Ppm
Iron 0.3 0.3 Ppm
Copper 2 1.5 Ppm
Biological parameters
E. Col 0 0 Counts/ml
Coliform 0 0 Counts/ml

Water quality monitoring

Water quality monitoring is vital for the protection of freshwater resources. Protection of
freshwater resources can be achieved through regular water quality monitoring. Regular
water quality assessment of water resources is important to determine suitability and safety
for different purposes. Conducting water quality assessment begins with evaluation of the
suitability of water based on its intended use.

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4. Expected output
 The raw water (influent) quality of gereb segen surface water source storage
reservoir will be analyzed
 The treated water (effluent) water quality will be analyzed and compare to water
quality standard
 The unit water treatment process performance will be evaluated

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 5. Schedule

Table 5.1 Activity Schedule

S. no Activity Duration
Nob Dec Jan Feb Mar Apr May June
1 Preparation of proposal
2 Proposal thesis defense
3 Site visit and Data collection
Data organizing and
4
processing
5 Thesis writing

6 First draft submission

7 Thesis progress presentation

8 Final thesis submission

9 Thesis presentation

Table 5-1:- detailed activity schedule

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 5.1. Budget
To accomplish this thesis work the following budget is required as shown in Table 5.2
Estimated budget

Table 5.2 estimated budget

Cost(birr)
S.no Description of item measurement quantity
Unit cost Total cost
1 Stationary
1.1 A 4 size paper Pack 1 400 400
1.2 Pens, pencils and erasers Pack 2 20 40
2 Data collection expense
2.1 for data collection Day 20*1 250 5000
2.2 GPS Item 1 days 500 500

2.3 Miscellaneous expense Birr 2000 2000

Sample 96 170 16320

3. Laboratory work
4. Secretary writing and
other expenses
4.1. Print expenses Page 70 3*3 630

4.2. Color print for images Page 10 11 110

Grand total 25,000

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References
ammo, t. (september 2018). assesment of water quality parametrs in artifical lake lake. in tropical
fresh water biology, 55.

BONZEMO, S. W. (2007 ). ASSESSMENT OF WATER QUALITY STATUS OF RIVER KIBISI, KENYA USING
THE EPHEMEROPTERA, PLECOPTERA AND TRICHOPTERA (EPT) INDEX . KENYA.

Bujar H. Durmishi, A. S. (March 2012). drinking water quality assesment in tetova region. americaln
journnal of environmental scince, 9.

FawazAl-Badaii, M.-O. a. (21July2013). Water Quality Assessment of the Semenyih River, Selangor,
Malaysia. JournalofChemistry, 10.

Jadhav2, S. P. ( Nov-Dec 2013). Assessment of Water Quality Parameters. Journal of Engineering

Research and Applications , 7.

matias bonansea, c. l. (2015). water quality assesment using multivariat statistical techniques in rio
tercero reservior. hydrology reaserch, 12.

Mauskar, J. (2007-08 ). Guidelines for Water Quality Monitoring . East Arjun Nagar, Delhi-32 : Central
Pollution Control Board Parivesh Bhawan .

MOSIMANEGAPE, K. (JULY 2016). Integration of physicochemical assessment of water quality with

Remote sensing techniques for the Dikgathong Dam in Botswana . botswana: WATERnet.

WHO. (2011). Guidelines for Drinking-water Quality. geneva: WHO.

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