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National

 

Water

 

Quality

 

Monitoring

   

Programme

 

Fifth

 

Monitoring

 

Report

 

(2005

06)

 

           

June

 

2007

 

 

 

Pakistan

 

Council

 

of

 

Research

 

in

 

Water

 

Resources

 

(PCRWR)

 

Khayaban‐e‐Johar Service Road South, 

H‐8/1, Islamabad‐Pakistan. 

Tele: 9258958, Fax: 9258963 

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Copyright © 2007 by PCRWR ISBN 978-969-8469-18-4

All rights reserved. Published in Pakistan

by Pakistan Council of Research in Water Resources (PCRWR), Khyaban-e-Johar, H-8/1, Islamabad – Pakistan

Email: pcrwr@isb.comsats.net.pk

Cataloging in Publication Data:

Kahlown, Muhammad Akram; Tahir, Muhammad Aslam and Hifza Rasheed. Water Quality Status of Pakistan (5th Technical Report 2005-2006).

Includes Annexures References:

I. Water Quality 2. Drinking Water 3. Water Resources – Pakistan I. Title II. Publication No.133-2007

628.16’095491

ISBN 978-969-8469-18-4

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CHAPTER-1

INTRODUCTION

Water is essential for the survival of all living things. Water makes up more than two thirds of the weight of the human body, and without it, humans would die in a few days. The human brain is made up of 95% water, whereas blood and lungs contain 82% and 90% water respectively (Fine waters, 2006) In addition to the daily maintenance of the body, water also plays a key role in the prevention of disease(s). Drinking eight glasses of water daily can decrease the risk of colon cancer by 45%, bladder cancer by 50% and it can reduce the risk of breast cancer (APEC, 2006). About 70% of the earth is covered with water and 97.5% of that constitutes salty oceans. The remaining 2.5% is fresh water, out of which less than 1% of freshwater is useable (Figure-1.1).

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Source: WWAP 2006, based on data from Shiklomanov and Rodda 2003

Freshwater would be enough to support the world’s population if used with care. Freshwater however, is not distributed evenly with respect to population. Although 60% of the world’s populations live in Asia, the continent has only 36% of the world’s water resources (Plan, 2005). Water and population distribution in different regions is shown in Figure 1.2.

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Source: Global Water Future, Center for Strategic and International Studies and Sandia National. www.unfpa.org

Without a minimum amount of water to consume, the human body rapidly deteriorates and ultimately death can occur due to dehydration. However, most people have access to some form of water supply that is sufficient to meet the very basic human needs, although these supplies may cause risks to their health because of their quality, with regards to basic hygiene.

1.1 Water Borne Diseases:

Most of the impacts are related to either water quality or water quantity. The consumption of water which is contaminated by disease-causing agents (or pathogens) or toxic chemicals can lead to health problems. These may be mild for instance (diarrhoea for one to two days), or very severe (including fatal effects). They may also be short-term (called acute), or long-term (called chronic). Poor hygiene may be caused by the use of inadequate volumes of water and may lead to skin and eye diseases. In addition, poor hygiene resulting from lack of adequate water is also a key factor in the transmission of many infectious diarrhoeal diseases.

Water quality is deteriorating in most regions and evidence indicates that the diversity of freshwater species and ecosystems is also getting adversely affected, rapidly; often faster than terrestrial and marine ecosystems. Poor water quality is the most important cause of poor livelihood and health. Globally, diarrhoeral diseases and malaria killed about 3.1 million people in 2002. Ninety percent of these deaths were of children under the age of five. In this context the following facts are documented in different reports like Global Water Supply & Sanitation Assessment Report (2000), World Water Vision, World Water Council (2000) and Environment Canada (2000):

. About 20% of the world’s population remains without access to safe drinking water. . About 40% of the world’s population has no access to sanitation facilities.

. Annually, more than 2.2 million people (mostly children under the age of five) die from problems associated with the lack of drinking water and sanitation.

. More than 6,000 children die each day from diseases associated with the lack of access to safe drinking water, inadequate sanitation and poor hygiene.

. In developing countries, about 80% of the illnesses are linked to poor water quality and sanitation conditions.

. Half of the world’s hospital beds are occupied by patients suffering from some form of a water-borne disease.

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who are unable to reach, or afford, safe drinking water.

1.2 Population and Water Supply:

According to an estimate given in a report of the Leadership for Environment and Development, by the year 2025 about 52 nations comprising half the world's population, will have a severe shortage of potable water. In the next 25 years, some 3 billion people will be facing water shortages. Similarly, the major issues of South Asia in this context are freshwater pollution and scarcity -limited access to potable water, water-borne diseases, arsenic contamination of drinking water, seasonal limitations of availability of natural freshwater resources, depletion of freshwater aquifers and organic pollution.

The population of Pakistan is now estimated to be more than 160 million. With the present growth rate of 1.8%, the population of the country is expected to have doubled by the year 2025. Per capita decline of water availability from 5600 m3 to 1,000 m3 has seriously raised the water quality and quantity concerns. It is estimated that around 40% of all reported diseases and deaths in Pakistan are attributed to poor water quality in the country. Moreover, the leading cause of deaths in infants and children up to 10 years of age, is that of contaminated water. The mortality rate of 136 per 1,000 live births due to diarrhoea is reported, while every fifth citizen suffers from illness caused by unsafe water. In Karachi, more than 10,000 people die annually of renal infection due to polluted drinking water. “The budget of the majority of the poor people was often consumed on the treatment of waterborne diseases owing to which they had little money left for improving their living standards.” (Dawn April 5, 2004).

1.3 National Water Quality Monitoring Program:

Considering the gravity of the water quality problems at such a national level, the Pakistan Council of Research in Water Resources (PCRWR) launched the “National Water Quality Monitoring Program” on March 17, 2001 for a period of five years. All five phases of the program have been completed. In this report, water quality data has been presented covering 23 major cities of Pakistan. These cities include Islamabad, Bahawalpur, Faisalabad, Gujranwala, Gujrat, Kasur, Lahore, Multan, Rawalpindi, Sargodha, Sheikhupura, Sialkot, Mangora, Abbottabad, Mardan, Peshawar, Khuzdar, Loralai, Quetta, Ziarat, Hyderabad, Karachi, Sukkur. The findings of this water quality monitoring program have in fact played a key role to sensitize the planning and implementing agencies responsible for the provision of safe drinking water to the public. As a result, the Government of Pakistan has seriously considered the matter and approved a number of safe water initiatives for the well being of the citizens. Detailed water quality profiles of 23 major cities of Pakistan are also available on the official website of PCRWR (www.pcrwr.gov.pk ). In this report, findings of the fifth and final phase of water quality monitoring are presented and discussed in detail. In addition, province wise and on country basis water quality status from 2002 to 2006 is also provided in order to further motivate the responsible authorities to solve the water quality problems on a priority basis to safe guard the public health. This noble cause was initiated by PCRWR whose capacity is being reflected from this report.

1.4 Scope of Fifth Monitoring Report:

The idea behind preparing this report was to document the water quality situation in target areas and to identify key issues for implementation of mitigation measures. The report consists of six chapters. Chapters 1 to 4 cover introduction, water quality standards, methodology and the water quality situation in 23 major cities in the year 2006. Chapter 5 presents the situation analysis from 2002 to 2006, whereas Chapter 6 presents a brief summary of findings and recommendations to rectify the unwanted situation. Based on the

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implement future water supply projects. For the general public, this report is an effective source to update their knowledge about the city’s water sources, water quality, and possible treatments.

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WATER QUALITY

STANDARDS

The basic purpose of establishing standards is to facilitate the provision of safe drinking water to the citizens. The World Health Organization (WHO) has provided guidelines for drinking water, which are advisory in nature, and are based on scientific research and epidemiological findings. The values of various water quality parameters recommended by the WHO are the general guidelines. That is why different countries have established their own water quality standards in order to meet their national priorities, taking into account their economic, technical, social, cultural, and political requirements. The Pakistan Standard Quality Control Authority (PSQCA) has come forth with the national drinking water quality standards which are in implementation for water quality monitoring. This matter needs to be addressed as a top priority. The WHO guidelines and standards proposed by national agencies like PCRWR, PSQCA, International Bottled Water Association (IBWA), Food and Drug Administration (FDA), Environmental Protection Agency (EPA) and other countries are documented in this chapter.

2.1 WHO Guidelines

A. Bacteriological Qualities

Source/Organisms Guideline Value

All water intended for drinking (E. Coli or Must not be detectable in any 100 ml sample. thermo tolerant Coliform bacteria).

Treated water entering the distribution system (E. Coli or thermo tolerant coliform and total coliform bacteria).

Must not be detectable in any 100 ml sample.

Treated water in the distribution system (E. Coli or thermo tolerant coliform and total coliform bacteria).

Must not be detectable in any 100 ml sample. In the case of large supplies, where sufficient samples are examined, it must not be present in 95% of samples taken throughout any 12-month period.

B. Chemicals of Health Significance

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Antimony Arsenic Barium Boron Cadmium Chromium 0.050 0.010 0.700 0.500 0.003 0.050 Copper Cyanide Fluoride Lead Manganese Mercury 2.000 0.070 1.500 0.010 0.500 0.001 Molybdenum Nickel Nitrate(NO3) Nitrite(NO2) Selenium Uranium 0.070 0.020 50.00 03.00 0.010 0.002

C. Other Parameters D. Pesticides

Parameter mg/l Parameter mg/l Parameter mg/l

Color Taste, Odor. Turbidity Toluene Xylenes Ethyl-benzene Styrene Monochlorobenzene 15 TCU -5 NTU 0.70 0.50 0.30 0.02 0.30 1,2 dichlorobenzene 1,4-dichlorobenzene Tetracholorethene Ethylbenzene Aluminum Ammonia Chloride Copper 1.00 0.30 0.04 0.30 0.20 1.50 250 1.00 Hardness, pH, DO Hydrogen sulfide Iron Sodium Sulfate TDS Zinc -0.05 0.30 200 250 1000 3 Pyradite 0.10 Chlorotoluron 0.03 1,2-dicholoropropane 0.04 Bentazon 0.30

2.2 US-EPA Guidelines

A. Inorganic Chemicals

Inorganic mg/l Inorganic mg/l Inorganic mg/l

Antimony Arsenic Barium Beryllium Cadmium Chromium 0.006 0.010 2.000 0.004 0.005 0.100 Copper Cyanide Fluoride Lead Manganese Mercury 1.00 0.20 2.00 0.015 0.050 0.002 Molybdenum Znic Nitrate(N) Nitrite(N) Selenium Aluminum 0.070 5.000 10.000 01.000 0.050 0.05-0.2

B.Other Parameters

Parameter mg/l Parameter mg/l Parameter mg/l

Color Atrazine Toluene Xylenes (total) Ethyl-benzene Styrene Chlorobenzene Benzene Oxamyl 15 TCU 0.003 1000 10.000 0.700 0.100 0.1 Zero 0.200 1,2 dichloropropane o-Dichlorobenzene p-Dichlorobenzene Endrin Ethylbenzene Methoxychlor Vinyl choloride Chloride Glyphosate Zero 0.600 0.075 0.002 0.700 0.040 0.002 250 0.700 pH Sulfate Iron Sodium Sulfate TDS Corrosivity 6.5-8.5 250 0.30 200 250 1000 Non-corrosive

C. Disinfectants

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Chloramines 4 Chlorine dioxide 0.8

Chlorine 4 Chlorite 1.0

2.3 PSQCA Water Quality Standards

A. Physical Requirements

Characteristics Unit MAC* MAC**

pH - 7.0-8.5 ≥ 6.5-≤ 9.2

Turbidity NTU 5 25

Colour TCU 5 50

Taste & Odor - Unobjectionable

B. Chemical Requirements C. Limits of Toxic Substances

Alkyl Benzyl Sulfates mg/l 0.5 1.0

Calcium (Ca) mg/l 75 200

Total Hardness (CaCO3) mg/l 20 500

Chloride (Cl) mg/l 200 600

Sulfate (SO4) mg/l 200 400

Nitrate (NO3) mg/l - 10

Total Dissolved Solids mg/l 1000 1500

Iron (Fe) mg/l 0.3 1.0

Fluoride (F) mg/l - 1.5

Hydrogen Sulfide mg/l Undetectable odor

Zinc (Zn) mg/l 5.0 15.0 Manganese (Mn) mg/l - 0.5 Copper (Cu) mg/l - 1.0 Magnesium (Mg) mg/l 50 150 Arsenic (As) mg/l 0.01 Cadmium (Cd) mg/l 0.003 Chromium (Cr) mg/l 0.05 Cyanide (Cn) mg/l 0.07 Lead (Pb) mg/l 0.01 Selenium (Se) mg/l 0.01

D. Limits for Bacteriological Contaminants

Acceptable bacterial standards for potable water supplies are as follows:

Escherichia coli 0/250 ml

Total Coliform 0/250 ml

Enterococci 0/250 ml

Pseudomonas aeruginosa 0/250 ml

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2.4 International Bottled Water Association (IBWA) Standards

A. Chemical Quality

Characteristics Unit Standard Characteristics Unit Standard

Arsenic (As) mg/l 0.01 Mercury (Hg) mg/l 0.001

Barium (Ba) mg/l 1.00 Nitrate (NO3) mg/l 10.00

Cadmium (Cd) mg/l 0.005 Nitrite (NO2) mg/l 1.00

Chromium (Cr) mg/l 0.05 Selenium (Se) mg/l 0.01

Chloride (Cl) mg/l 250 Silver (Ag) mg/l 0.025

Copper (Cu) mg/l 1.00 Sulfate (SO4) mg/l 250.0

Cyanide (CN) mg/l 0.10 Phenolic mg/l 0.001

Fluoride (F) mg/l 4.00 PCB mg/l 0.0005

Iron (Fe) mg/l 0.30 TDS mg/l 500.0

Lead (Pb) mg/l 0.005 Zinc (Zn) mg/l 5.00

Manganese (Mn) mg/l 0.05 Turbidity NTU 0.50

B. Microbiological Quality

2.5 Food and Drug Administration (FDA) Standards

Characteristics Unit Standard Characteristics Unit Standard

Arsenic (As) mg/l 0.05 Nitrate (NO3) mg/l 10.0

Barium (Ba) mg/l 1.00 Selenium (Se) mg/l 0.01

Cadmium (Cd) mg/l 0.01 Silver (Ag) mg/l 0.05

Chromium (Cr) mg/l 0.05 Sulfate (SO4) mg/l 250

Chloride (Cl) mg/l 250 Phenolic mg/l 0.001

Copper (Cu) mg/l 1.00 Ra 226 activity (pCi/l) - 5.00

Iron (Fe) mg/l 0.30 Total Beta activity (pCi/l) - 8.00

Lead (Pb) mg/l 0.05 TDS mg/l 500.0

Manganese (Mn) mg/l 0.050 Zinc (Zn) mg/l 5.0

Mercury (Hg) mg/l 0.002 Coliform (MPN/100 ml) <2,20

2.6 Indian Water Quality Standards

A. Physical and Chemical Standards

Characteristics (mg/l) Acceptable Marginal Sr. #. Characteristics (mg/l) Acceptable Marginal

Turbidity (NTU) 2.5 10 15 Copper 0.05 1.5

Colour (TCU) 5 25 16 Zinc 5.0 15.0

Taste & Odor Unobjectionable 17 Phenolic Compounds 0.001 0.002

PH 7-8.5 6.5-9.2 18 Anionic Detergents 0.2 1.00

TDS 500 1500 19 Arsenic 0.05 0.05

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Chloride 200 1000 21 Chromium 0.05 0.05

Sulfate 200 400 22 Cyanide 0.05 0.05

Fluoride 1.0 1.5 23 Lead 0.1 0.1

Nitrate (N) 45 45 24 Selenium 0.01 0.001

Calcium 75 200 25 Mercury 0.001 0.20

Magnesium 30 150 26 Polynuclear aromatic

hydrocarbons (g/l)

0.2 3.00

Iron 0.10 1.00 27 Gross Alpha Activity 3 (pCi/l) 30.0

Manganese 0.05 0.50 28 Gross Beta Activity 30 pico

(pCi/l) curie/l

Note:

The values indicated under the column “Acceptable” are the limits up to which the water is generally acceptable to the consumers.

Values in excess of those mentioned under “Acceptable” render water not acceptable, but still may be tolerated in absence of an alternative and a better source, but up to the limits indicated under the column “Marginal”, above which the supply will have to be rejected.

B. Bacteriological Standards

i) Water entering the distribution system coliform count in any sample of 100 ml should be zero. ii) Water in the distribution system shall satisfy all the three criteria indicated below:

E.Coli count in 100 ml of any sample should be zero;

Coliform organisms no more than 10 per 100 ml shall be present in any sample;

Coliform organisms should not be detectable in 100 ml of any two consecutive samples or more than 50% of the samples collected for the year.

iii) Individual or small community supplies.

E.Coli count should be zero in any sample of 100 ml and coliform organisms should not be

more than 3 per 100 ml.

C. Virological Aspects

A level of 0.5 mg/l of free chlorine residual for one hour is sufficient to inactivate virus, even in water that was originally polluted. This free chlorine residual is to be insisted in all disinfected supplies in areas suspected of endemicity of infectious hepatitis to take care of the safety of the supply from the viral point of view, which incidentally takes care of the safety from the bacteriological point of view as well. For other areas 0.2 mg/l of free chlorine residual for half an hour should be insisted.

2.7 Water Quality Standards of Indonesia, Singapore, Malaysia, Thailand, Philippines and Brunei.

A. Chemical Quality

Substances Unit Indonesia Singapore Malaysia Thailand Philippines Brunei

Arsenic (As) mg/l 0.05 0.05 0.05 0.05 0.05 <0.003 Barium (Ba) mg/l - 1 - 1 - <0.02 Borate (BO3) mg/l - 0.03 30 - - 0.20 Cadmium (Cd) mg/l 0.1 0.01 0.01 0.005 0.01 <0.002 Chromium (Cr) mg/l - 0.05 0.05 0.05 0.05 <0.01 Chloride (Cl) mg/l 250 0.05 - 250 - -

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Chlorine (Cl2) mg/l - - 1 1 - - Copper (Cu) mg/l 0.5 - - 0.1 1 <0.01 COD mg/l - - - 1 - - Cyanide (CN) mg/l 0.05 0.01 0.01 - 0.01 - Fluoride (F) mg/l 1 2 2 - 2 0.09 Hardness (CaCO3) mg/l 170 - - 100 - - Iodine (I) mg/l - 1 - 0.3 - - Iron (Fe) mg/l 0.1 - - 0.05 1 - Lead (Pb) mg/l 0.05 0.05 0.05 0.05 0.05 <0.01 Manganese (Mn) mg/l 0.05 2 2 0.002 0.1 0.01 Mercury (Hg) mg/l 0.001 1 0.001 - 0.001 <0.001 Mineral Oil mg/l - ND ND - - - Nitrate (NO3) mg/l ND 45 45 4 (N) 45 <0.05 Nitrite (NO2) mg/l ND 0.005 0.005 - 0.01 <0.005 Organic Matter mg/l 1 0.003 3 - 5 - Selenium (Se) mg/l - 0.01 0.01 0.01 0.01 <0.01 Silver (Ag) mg/l - - - 0.05 - - Surfactant mg/l - ND ND - 2 - Sulfide (S) mg/l ND 0.05 0.05 - - - Sulphate (SO4) mg/l 200 - - 250 - - Phenolic mg/l - ND ND 0.001 0.001 - Ra 226 activity pCi/l - 30 - - - -

Total Beta activity pCi/l - 1 - - - -

TDS mg/l 500 - - 500 - -

Zinc (Zn) mg/l - - 5 5 5 -

B. Microbiological Quality

Total Plate Count/ml Max

1x104

Max.1x105

- - - -

Coliform (MPN/100 ml) <2.20 0/250 ml Max.10 <2.20 <2.20 Nil

Escherichia coli 0 0 0 Negative - Nil

Salmonella/100 ml - 0 - - - - Staphylococcus Aureus/250 ml - 0 - - - - Pseudomonas Aeruginosa/250 ml 0 0 - - - - Faecal Streptococci/20 ml - - - - 1/100 ml -

2.8 Water Quality Standards of Vietnam, Japan, China, Hong Kong, Korea and Taiwan

A. Chemical Quality

Substances Unit Vietnam Japan China H. Kong

Korea Taiwan

Arsenic (As) mg/l 0.05 <0.2 0.05 0.01 0.05 0.05

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Barium (Ba) mg/l - - - 0.7 - - Borate (BO3) mg/l 10 - - 0.3 - - Cadmium (Cd) mg/l 0.01 <0.05 0.01 0.003 0.01 0.01 Chromium (Cr) mg/l - <0.05 0.05 0.05 0.05 0.05 Chloride (Cl) mg/l - <350 250 250 150 250 Chlorine (Cl2) mg/l - - - 1 Copper (Cu) mg/l 1 <0.05 1 2 1 0.01 COD mg/l - - - 0.8 Cyanide (CN) mg/l 0.01 <0.01 0.01 0.07 ND - Fluoride (F) mg/l 2 <1.5 0.8 1.5 1 - Hardness (CaCO3) mg/l - 100-500 250 - 300 250 Iodine (I) mg/l - - - 0.3 Iron (Fe) mg/l - <0.1 0.3 0.3 0.3 0.05 Lead (Pb) mg/l 0.05 <0.1 0.05 0.01 0.1 0.05 Manganese (Mn) mg/l 2 <0.1 0.05 0.5 0.3 0.001 Mercury (Hg) mg/l - - 0.001 0.001 ND - Nitrate (NO3) mg/l 45 <5.0 10 50 10 10 Nitrite (NO2) mg/l - - ND 3 - ND Organic Matter mg/l 3 - 0.1 - - 0.1 Selenium (Se) mg/l - <0.05 0.01 0.01 0.01 0.01 Silver (Ag) mg/l 0.01 - 0.05 - 0.05 Sulphate (SO4) mg/l - <250 250 250 200 250 Phenolic mg/l - <0.001 - - 0.005 -

Total Beta activity pCi/l - - - 1.0 Bq/I - -

TDS mg/l - <1000 500 1000 - 500

Zinc (Zn) mg/l 5 <5 5 3 1 5

B. Microbiological Quality

1 Total Plate Count/ml <10 - 100 - <100 -

2 Coliform (MPN/100 ml) - <15.100 3 <2.2 0 -

3 Escherichia coli 2.2 - - - - 0/100 ml

2.9

Water Quality Standards of Saudi Arabia, Guam, Australia, Argentina, Mexico and

Canada

A. Chemical Quality

Substances Unit S.

Arabia Guam Australia Argentina Mexico Canada

Arsenic (As) mg/l 0.05 0.05 0.05 0.05 0.05 0.025

Ammonium (NH4) mg/l - - - 0.2 0.5 -

Barium (Ba) mg/l 1 1 1 - 0.7 1

Borate (BO3)

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Cadmium (Cd) mg/l 0.01 0.01 0.005 0.01 0.005 0.005 Chromium (Cr) mg/l 0.05 0.05 0.05 0.05 - 0.05 Chloride (Cl) mg/l 250 250 - 350 250 - Chlorine (Cl2) mg/l - - 0.01 0.5 0.1 - Copper (Cu) mg/l 1 1 1 2 1 - COD mg/l - 3 - - - Cyanide (CN) mg/l 0.05 - 0.1 0.10 - 0.2 Fluoride (F) mg/l - - 1.5 2 2 - Iron (Fe) mg/l 0.3 0.3 - 2 0.3 - Lead (Pb) mg/l 0.05 0.05 - 0.05 0.02 0.01 Manganese (Mn) mg/l 0.05 0.05 2 0.1 0.05 - Mercury (Hg) mg/l - 0.002 0.001 0.001 0.001 0.001 Nitrate (NO3) mg/l - 10 45 45 10 45 Nitrite (NO2) mg/l - - 0.01 0.1 - 3.2 Selenium (Se) mg/l - 0.01 0.01 - 0.05 0.01 Silver (Ag) mg/l 0.05 0.05 - 0.05 - - Surfactant mg/l - - - - 0.5 - Sulfide (S) mg/l - - 0.05 - - - Sulphate (SO4) mg/l 250 250 - 500 250 - Phenolic mg/l 0.001 0.001 - - 0.001 - Ra 226 activity pCi/l 3 5 1 - - -

Total Beta activity pCi/l - 8 - - - -

TDS mg/l - 500 - 1500 500 -

Zinc (Zn) mg/l 5 5 5 5 3 -

B. Microbiological Quality

Total Plate Count/ml - - <1 500 100 100

Coliform (MPN/100 ml) - <2.20 Max.10 3 <2 -

Escherichia coli - - - Negative - 0

Pseudomonas Aeruginosa/250

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CHAPTER-3

METHODOLOGY

The general methodology adopted for the National Water Quality Monitoring Program consisted of establishing a network for the collection of water samples, monitoring stations, grid and sample size, frequency, sample collection and preservations, preparation of a check list, analytical methods, recording of groundwater level etc. The details of these components are given below:

3.1 Scope of Monitoring Program

The National Water Quality Monitoring Program covers twenty-three main cities with the following distribution, Islamabad, 11 in Punjab, 3 in Sindh, 4 in Balochistan, and 4 in NWFP. The monitoring program also cover 9 rivers, 6 reservoirs, 4 lakes, 1 drain and 2 canals. For water quality data collection purposes, the country was divided into five zones, namely Capital Territory Area, Punjab (two zones), Sindh, Balochistan, and NWFP. The field teams of the sub offices were assigned the tasks of sample collection and analysis in the respective zones. The details of the Monitoring Stations (MS) and their areas of responsibility in terms of the collection of water samples for water quality monitoring were as under:

Monitoring Station-I (WRRC, Islamabad), collected water samples from; Islamabad, Rawalpindi,

Gujrat and Sargodha cities, Simly, Rawal and Khanpur dams, Tarbella, Mangla and Chashma reservoirs and Jhelum and Chenab Rivers.

Monitoring Station-II (Regional WRRC, Lahore), collected water samples from; Lahore, Sialkot,

Sheikhupura, Gujranwala, Faisalabad and Kasur cities, and Ravi River

Monitoring Station-III (Regional WRRC, Bahawalpur), collected water samples from;

Bahawalpur and Multan cities, and Sutlaj River

Monitoring Station-IV (Drainage Research Center, Tandojam), collected water samples from;

Hyderabad, Karachi and Sukkur cities, Manchar and Hamal lakes, LBOD, RBOD and Hub dam and Indus River

Monitoring Station-V (Regional WRRC, Quetta), collected water samples from; Quetta, Khuzdar,

Loralai and Ziarat cities, and Hanna Lake

Monitoring Station-VI (Regional WRRC, Peshawar), collected water samples from; Abbottabad,

Peshawar, Mardan and Mangora cities, and Indus and Kabul Rivers

3.2 Grid Size and Number of Samples

A uniform criterion for site selection was adopted and a grid size of 1 km2 (for small cities), 4 and 9 km2 (for medium cities) and 16 and 25 km2 (for large cities) was established. Preference was given to permanent public points for their selection as permanent monitoring points, considering the long term monitoring requirement of the project. Geology and the depth of aquifers was also considered. A minimum distance of 1 km was maintained between the two monitoring points. A site identification code was marked on each city map according to the grid. A sample ID, for a monitoring purpose, was marked on the basis of an actual sampling visit sequence of various sites. The following identifications were also marked on every sample of each site:

Type-A for Bacterial analysis Type-B for Trace element analysis

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Type-C for Nitrate (N) analysis

Type-D for Other water quality parameters

The details regarding grid size and the number of sampling points are given in Table-3.1.

Table-3.1 Details of Water Quality Monitoring Network

Sr. #

City Name City Code Grid Size (km2) Total Sample Points Sr. #

City Name City Code Grid Size (km2) Total Sample Points

1 Islamabad ISL 4 26 13 Abbottabad ABT 1 11

2 Bahawalpur BAH 16 25 14 Mangora MAN 1 12

3 Faisalabad FAI 4 13 15 Mardan MAR 4 10

4 Gujranwala GUJ 4 14 16 Peshawar PES 16 13

5 Gujrat GUT 1 9 17 Khuzdar KHU 1 11

6 Kasur KAS 1 10 18 Loralai LOR 1 13

7 Lahore LAH 16 18 19 Quetta QUE 4 25

8 Multan MUL 16 16 20 Ziarat ZIA 1 11

9 Rawalpindi RAW 9 15 21 Hyderabad HYD 4 15

10 Sargodha SAR 4 24 22 Karachi KAR 25 28

11 Sheikhupura SHE 4 11 23 Sukkur SUK 1 12

12 Sialkot SIA 4 10

3.3 Water Sample Collection and their Preservation

Water samples for physico-chemical analysis were collected in polystyrene bottles of 0.5 and 1.5

liter capacity. Before collecting the samples, the bottles were washed properly and rinsed

thoroughly several times, with the water that had to be sampled. For bacterial analysis, samples

were collected in sterilized containers. Hydrochloric acid and boric acid were used as

preservatives in 200 ml sampling bottles, for trace elements and nitrate as nitrogen respectively.

The sampling team comprised of an Assistant Director as Incharge of the team assisted by a

Laboratory Assistant and a driver. The following procedure and precautionary measures were

followed while collecting samples from the field.

3.3.1 Water Sample Collection from Tap Water

Un-rusted taps were selected for the collection of water samples. These taps were

thoroughly cleaned and allowed to flow for a few minutes before collecting the sample.

3.3.2 Water Sample Collection from Tube well Water

The groundwater representative samples from tubewells were collected after allowing

them to flow continuously for at least 10 minutes. The depth of the groundwater level was

than recorded. The location of the tubewell was properly marked on the topographic survey

sheet.

3.3.3 Water Sample Collection from Distribution Network Water

The water samples from the distribution network were collected from a point near the

source of supply (as close as possible) and from the consumers end, in order to evaluate the

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actual quality of water being used. All water sample containers were filled slowly, so as to

avoid turbulence and one formation of air bubbles, after flushing the system for sufficient

time.

3.3.4 Water Sample Collection from Hand Pump/Dug Well Water

Water samples were collected from hand pumps and dug wells, after the sufficient purging

of the hand pump or well. The purging was carried out by making one stroke for every foot

of depth (a hand pump or dug well having 30 feet of depth, needs 30 strokes for its

purging).

3.3.5 Water Sample Collection from Stream Water

Water samples were collected from the middle of the stream. Care was taken to keep the

bottle well above the bed of the stream in order to avoid unwanted bed material from

entering the sample.

3.3.6 Water Sample Collection from Spring Water

Water samples were collected directly from the spring in sterilized sampling bottles for

microbiology and bottles used with or without preservatives depended upon the water

quality analysis requirement.

3.3.7 Water Sample Collection from Dam, River and Lake Water

Generally, it is difficult to obtain truly representative surface water samples. A sampling

point was selected carefully (near to the bank in case of a river) in order to avoid any kind

of debris in the water. Considerable variations like seasonal stratification, runoff, rainfall

and wind, were also documented while collecting water samples, especially from lakes.

3.3.8 Microbiological Samples

The water samples for microbiological contamination were collected in clean, sterile 200

ml plastic bottles. Care was taken to ensure that no accidental contamination occurred

during sampling. Samples were not taken from those taps, which were leaking between the

spindle and gland so as to avoid outside contamination. The samples were kept cool and in

the dark while being transported to the laboratory.

3.4 Types of Water Samples and Preservatives

Samples were collected for microbiological analysis, trace elements, Nitrate (N) and other general

water quality parameters. The details of these samples and preservative used for each sample are

given below:

Type A– All sites – Sterilized sampling bottles for microbiological analysis;

Type B– All sites – 2 ml/liter HNO

3 as preservative for trace elements;

Type C– All sites – 1 ml/100 ml, 1 ml boric acid as preservative for Nitrate (N); and Type D– All sites – No preservative for other water quality parameters.

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3.5 Check List

3.5.1 Check List of Items/Activities Needed Before Going to Field

Number of bottles required for sampling.

Filling of appropriate preservatives in the sampling bottles. Calibration of field equipment.

General items required for sampling e.g., sampling forms, equipment, markers, ballpoints, distilled

water and paint etc.

3.5.2 Check List of Items/Activities Needed During Collection of Samples

City map with grids and identified ID site. During the site finalization, ensure that the site selection meets the criteria of the representative sample. Filling site and sample ID in the form.

Sample bottle with the date and sample ID with indelible ink. Sample bottles preserved with the appropriate preservative. Finalization of the method to be used for sample collection. Ensuring the collection of four water quality samples.

Confirm cross, field blanks and also replicate samples from suitable sites.

Marking of ‘P’ on site after collecting sample for future reference and the use of red paint.

3.5.3 Check List Items/Activities after Collection of Samples

Transportation of samples to the laboratory within the recommended time period. Water samples are not to be filtered.

Purpose of sample collection is properly explained to the communities.

3.6 Quality Control Measures

Quality control measures were started from the field. Standard sampling methods were adopted to collect the samples. Four types of samples were collected for monitoring purposes whereas three kinds of samples were collected for quality control. The details of these samples are as under:

i) Samples for Monitoring Purposes

a) Samples for microbiological examinations in sterile bottles.

b) Samples for the analysis of trace elements by the addition of HNO3 as a preservative.

c) Samples for the analysis of Nitrate (N) by the addition of boric acid as a preservative. d) Samples without preservatives for the analysis of EC, pH, Hardness, Ca, Mg, Na, K and

HCO3 etc.

ii) Samples for Quality Control Purposes

Field blank and replicate samples for quality control purposes were also collected. Sites for field blank and replicates were selected on the basis of total site number divisible by 20. a) Samples to check reproducibility (10%).

b) Samples for field blank (10%).

Replicate samples and field blanks were analyzed to see the reproducibility of analytical results and to check the quality of distilled water respectively. The results of replicate samples and field blank are given in

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comparison.

3.7 Methods for Analysis

The water samples were analyzed for physical, chemical and bacteriological parameters by using standard methods. The details of the parameters and methods used for their analysis are given in table 3.2.

Table 3.2 Water Quality Parameters and Methods used for Analysis Sr. No Parameters Analysis Method

1. Alkalinity (m.mol/l as CaCO3)

2320, Standard method (1992)

2. Arsenic (ppb) AAS Vario 6, Analytik Jena AG

3. Bicarbonate 2320, Standard method (1992)

4. Calcium (mg/l) 3500-Ca-D, Standard Method (1992)

5. Carbonate (mg/l) 2320, Standard method (1992)

6. Chloride (mg/l) Titration (Silver Nitrate), Standard Method (1992)

7. Color (TCU) Sensory Test

8. Conductivity (μS/cm) E.C meter, Hach-44600-00, USA

9. Lead (ppb) AAS Vario 6, Analytik Jena AG

10. Hardness (mg/l) EDTA Titration, Standard Method (1992)

11. Magnesium (mg/l) 2340-C, Standard Method (1992)

12. Nitrate (mg/l) Cd. Reduction (Hach-8171) by Spectrophotometer

13. Odor Sensory Test

14. pH pH Meter, Hanna Instrument, Model 8519, Italy

15. Potassium (mg/l) Flame photometer PFP7, UK

16. Sodium (mg/l) Flame photometer PFP7, UK

17. Sulfate (mg/l) SulfaVer4 (Hach-8051) by Spectrophotometer

18. Phosphate (mg/l) 8190 and 8048 (Hach)

19. Taste Sensory Test

20. TDS (mg/l) 2540C, Standard method (1992)

21. Turbidity (NTU) Turbidity Meter, Lamotte, Model 2008, USA

22. Fluoride (mg/l) 4500-F C. ion-Selective Electrode Method Standard method

(1992)

23. Iron (mg/l) TPTZ method (HACH Cat. 26087-99)

24. Total Coliform

(MPN/100ml)

9221-B, Multiple tube Fermentation Technique, Standard Methods for the Examination of Water and Waste Water 25. E. Coli (MPN/100ml) 9221-E, Multiple tube Fermentation Technique, Standard

Methods for the Examination of Water and Waste Water 26. Trace and Ultra Trace

Elements (Ag, Al,B, Be, Bi, Cd, Ce, Co, Cr, Cu, Dy, Er, Eu,F,Fe, Ga, Gd,Ge,Hf, Hg, Ho, In, Ir, La, Li, Lu, Mn, Mo, Nb, Nd, Ni, Pb, Pd, Pr,Pt, Rb, Re, Rh, Ru, Sc, Se, Sm, Sn,Sr, Ta, Tb, Te, Th, Ti, TI, Tm, V, W, Y, Yb, Zn, Zr)

(21)

A parameter wise detail of the analytical methods and procedures adopted for water quality

analysis is as follows;

pH

For most practical purposes the pH of an aqueous solution can be taken as the negative logarithm

of the solutions hydrogen ion concentration. The practical pH scale extends from 0 to 14 with the

middle value of 7 corresponding to exact neutrality at 25

o

C. The pH of natural water is usually

governed by the carbon dioxide/bicarbonate/ carbonate equilibrium and lies in the range between

4.5 and 8.5. Humic substances may affect it by changes in the carbonate equilibrium due to

bioactivity of plants and in some cases by hydrolysable salts

etc

. Waste waters and polluted waters

may have pH values much lower or higher.

On site determination of the pH of the samples was done in most of the cases. In other cases where

the pH meter was not available samples were collected and transferred in completely filled, well

stoppered bottles in order to prevent changes in their composition, especially in carbon dioxide.

The method used for this analysis was Electrometric Method (Reference method). The pH meter

was standardized according to the manufacturer’s instructions. Before measuring the pH of the test

samples, the electrode was washed thoroughly first with distilled water and then with the sample

water. The electrode was then dipped into the sample and the system was allowed to stabilize

before making the final reading. Determination was made in unstirred solutions in order to avoid

the loss of carbon dioxide or other volatile components.

Conductivity

Conductivity is a measure of the ability of an aqueous solution to carry an electric current. This

ability depends on the presence of ions, their total concentration, mobility, valence and on the

temperature of measurement. Solutions of most inorganic compounds are relatively good

conductors. Conversely molecules of organic compounds do not dissociate in aqueous solutions.

The determination of electrical conductivity provides a rapid and convenient means of estimating

the concentration of electrolytes in water containing mostly mineral salts. The apparatus used for

this analysis was the EC meter, HACH-44600, USA, Jenway, 4320.

The samples were shaken thoroughly before taking any measurements and then allowed to

stabilize until the removal of any attained air bubble(s). EC meter was standardized with the help

of a standard solution of potassium chloride, 0.01 M at a constant temperature of 25

o

C. The

conductivity cell was then thoroughly rinsed with distilled water as well as a small amount of the

sample. The beaker was filled with some of the sample. The EC of the samples was noted from the

screen of EC meter. Temperature affects conductivity in such that it varies by about 2% per 1

o

C.

The temperature of 25

o

C is taken as standard. Dissolved carbon dioxide increases conductivity without increasing the mineral salt content. The same is true for a sample with a low pH value, owing to the high equivalent conductivity of the hydrogen ion. However, the effect is not large and the removal of carbon dioxide from hard water cannot be achieved without a risk of precipitating calcium carbonate.

Turbidity

Turbidity is an expression of the optical property that causes light to be scattered and absorbed rather than to be transmitted in a straight line through the sample. Suspended matter such as clay, silt, fine organic, inorganic substances, soluble colored organic compounds, plankton and other microscopic organisms cause

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turbidity in water. The correlation between turbidity and weight concentration of suspended matter is difficult to derive due to the size, shape and refractive index of the particulates that affect the scattering properties of the light in the suspension. Optically black particles (activated carbon) may absorb light and effectively increase the turbidity measurements. The turbidity is of interest for two main reasons. First, turbidity is an important parameter for characterizing the water quality. Water treatment plants need its values for the treatment of surface water. Secondly, knowledge of the turbidity allows an estimate to be made of the concentration of un-dissolved substances.

The samples were collected in plastic bottles. The turbidity of the samples was measured just after their collection, as irreversible changes may occur in turbidity as a result of long period of storage. The method used for this analysis was the Nephelometric method. The apparatus consisted of a Turbidity meter, Hanna HI 93703. The turbidity method was based on a comparison of the intensity of light scattered by the sample under defined conditions, with the intensity of light scattered by a standard reference suspension under the same conditions. The higher the intensity of scattered light, the higher the turbidity. Formazin polymer was used as the referential turbidity standard suspension. Turbidity determination is applicable to water samples that are free from debris and other rapidly settling coarse sediments. Dirty glassware, the presence of air bubbles, and the effects of vibrations that disturb the surface visibility of the sample will give rise to false results. “True color” (water color) due to dissolved substances may absorb light and cause low turbidity values. This effect usually is, however not significant in the case of treated water.

a) Measurement of turbidity less than 40 NTU.

The samples were vigorously shaken till the disappearance of all air bubbles. The sample was then poured into the turbidity meter curette. The turbidity was read directly from the instrument scale.

b) Turbidity exceeding 40 NTU

The samples were diluted with one or more volumes of turbidity free water enabling it to fall below 40 NTU. The turbidity values were then calculated using the following equation.

Nephelometric turbidity units (NTU) = Ax (BxC)

C Where;

A= NTU found in diluted samples B= Volume of dilution water, ml and C= Sample volume taken for dilution, ml

Taste

Taste refers to those gustatory sensations known as bitter, salty, sour and sweet, that result from

the chemical stimulation of sensory nerve endings located in the papillae of the tongue and soft

palate. Flavor refers to a complex of gustatory, olfactory and trigeminal sensations resulting from

the chemical stimulation of sensory nerve endings located in the tongue, nasal cavity and oral

cavity. Water samples taken into the mouth for sensory analysis always produce a flavor, although

taste, odor or mouth-feel may predominate, depending on the chemical substances present. Taste

tests were performed only on samples that were known to be sanitarily acceptable for ingestion.

The method used for this analysis was that the sample taste was carried out at the original

temperature of the sample, after rinsing the mouth out with a portion of the sample for some

seconds on the tongue. The result of a sample test was described only qualitatively. The person

tasting the water must avoid eating, drinking or smoking before taking the test. Only 4 true taste

sensations; salty, sweet, bitter and sour were used for reporting taste results.

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Alkalinity

Alkalinity of water is its acid-neutralizing capacity. The measured value may vary significantly

with the end point pH used. The alkalinity is primarily a function of carbonate, bicarbonate and

hydroxide contents. The measured values may also include contributions from borates, phosphate,

silicates or other bases if present. Alkalinity measurements are used in the interpretation and

control of water and waste water treatment processes. Raw domestic waste water has an alkalinity

less than or slightly greater than that of the water supply. The method used for this analysis was the

2320 Standard Method (1992). The chemicals used for this analysis included:

i) Sodium carbonate solution, 0.05 mol/l; ii) HCl 0.02 M;

iii) Phenolphthalein indicator; and

iv) Mixed indicator (bromocresol green + methylred).

A 10 ml sample was mixed with 2 or 3 drops of phenolphthalein indicator in a conical flask. The

phenolphthalein alkalinity of the sample was determined by titrating with a standard acid (HCl

0.02 M) until the disappearance of the pink colour. The alkalinity due to the phenolphthalein was

considered to be zero in case no colour was produced after the addition of a few drops of

phenolphthalein. The methyl orange alkalinity of the sample was determined by titrating with a

standard acid (HCl 0.02 M) until the colour changed from blue to pink.

Total alkalinity as CaCO

3 (mg/lit)= 1000xBx1000xAxN V

where:

A= ml of standard acid solution to reach the end point; N= normality of acid used and

V= ml of sample.

Using 100 ml of the sample and 0.1 mol/l standard acid solution, the numerical value of alkalinity is directly expressed in m.mol/l by the number of ml of titrant consumed.

Bicarbonate (HCO3)

Bicarbonates are the dominant anions in most surface and ground waters. The weathering of rocks contributes to the bicarbonate content in water. Mostly, bicarbonates are soluble in water and its concentrations in water are related to the pH. Bicarbonates are usually less than 500 mg/l in groundwater. They also influence the hardness and alkalinity of the water. No guideline values are recommended by the WHO. The method used for this analysis was the 2320 Standard Method (1992).

The reagents used for this analysis include:

i) Mixed indicator (bromocresol green + methyl red) and ii) Standard acid (HCl) 0.02 N.

10 ml of the sample was taken in a flask and to it was added one drop of a mixed indicator. It was then titrated against the standard acid until the colour changed from bluish green to pink, and the volume of acid used was recorded as “R2”.

Bicarbonate mg/l= R2 x20-R1x20x2

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R1= Volume of acid used for phenolphthalein alkalinity.

Carbonate (CO3)

The method used for this analysis again was the 2320 Standard Method (1992). The reagents used for this analysis included:

i) Standard solution 0.02 N HCl; and ii) Phenolphthalein indicator.

10 ml of the sample was taken in a flask, and to it was added one drop of a phenolphthalein indicator. The carbonate was considered to be zero, in the case of no pink colour. If the sample turned to a pink colour, the sample was titrated against the standard acid until it became colourless.

Calcium (Ca)

The presence of calcium in water supplies results from its passage through or over deposits of limestone, dolomite, gypsum and gypsiferous shale. The calcium content may range from zero to several hundred milligrams per litre, depending on the source and treatment of the water. Small concentrations of calcium carbonate combat the corrosion of metal pipes by laying down a protective coating. Appreciable calcium salts, on the other hand, precipitate on heating to form a harmful scale in boilers, pipes and cooking utensils. Chemical softening, reverse osmosis, electro dialysis and ion exchange is used to reduce calcium and the associated hardness.

Samples were collected in plastic bottles without the addition of a preservative. The samples were re-dissolved by the addition of nitric acid in case of precipitation of calcium carbonate produced during sample storage before analysis. The method used for this analysis was the Disodium Ethyleediaminetetraacetic acid (EDTA) titration method (reference method). When EDTA is added to water containing calcium and magnesium ions, soluble EDTA chelates are formed. The stability constant for the calcium chelates is larger than that for the magnesium chelate consequently, in a titration, calcium reacts before the magnesium. Calcium can be determined in the presence of magnesium by EDTA titration when an indicator is used that reacts with calcium only e.g. Murexide gives a colour change when all of the

calcium has been complex by EDTA at a pH of 12 to 13.

Orthophosphate precipitates calcium at the pH of the test and, therefore, produces low results. Strontium and barium interfere with the calcium determination by virtue of the fact that they also form EDTA chelates and alkalinity in excess of 30 mg/l may cause an indistinct endpoint with hard water. The concentration levels of ions which cause interference with the calcium hardness are given in Table 4.3.

Table 4.3: Recommended Level of Concentrations of Ions for Non-Interference of Calcium

Copper 2 mg/l Ferrous iron 20 mg/l Zinc 5 mg/l Tin 5 mg/l

Manganese 10 mg/l Ferric iron 20 mg/l Lead 5 mg/l Aluminum 5 mg/l

The reagents used for this analysis included:

i) Sodium hydroxide (NaOH), 1M; ii) Murexide indicator; and

iii) Standard EDTA titrant, 0.01 M.

Take 10 ml of the sample and add 10 ml deionized water to it. Then add half ml of NaOH solution

or a volume sufficient to obtain a pH of 12-13. After stirring well, 0.1-0.2 gm of the Murexide

indicator is added. Then the EDTA titrant is added slowly, where continuously stirring, until the

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proper end point is reached.

Concentration of Ca (mg/l) = AxBx400.8 V

where:

A= ml of EDTA titrant used for titration of sample:

B= ml of standard calcium solution; and ml of EDTA titrant

V= ml of sample.

Magnesium (Mg)

Magnesium ranks eighth among the elements in order of abundance and is a common constituent

of natural water. Water associated with granite or siliceous sand may contain less than 5 mg of

magnesium per litre. Water containing dolomite or magnesium-rich limestone may contain 10-50

mg/l, and several hundred mg/l of magnesium may be present in water that has been in contact

with deposits containing sulfates and chlorides of magnesium. Magnesium by a similar action to

calcium, imparts the property of hardness to water. This may be reduced either by chemical

softening or ion exchange methods. The method used for analyzing magnesium concentration was

the 2340-C, Standard Method (1992). Magnesium was estimated as the difference between

hardness and calcium as CaCO

3.

Concentration of Mg (mg/l) = [total hardness (as CaCO3 mg/l)–Calcium hardness (as mg CaCO3/l) x

0.243].

Hardness

Originally, water hardness was understood as a measure of the capacity of water to precipitate soap. In conformity with current practice, total hardness is defined as the sum of the calcium and magnesium concentrations, both expressed as calcium carbonate, in milligram per litre. The hardness may range from zero to hundreds of milligrams per litre, in terms of calcium carbonate, depending on the source and treatment to which the water has been subjected. Samples were collected in plastic bottles without the addition of a preservative. The method used for this analysis was the EDTA Titration Standard Method (1992).

EDTA forms soluble chelates of calcium and magnesium ions. When a small amount of Eriochrome Black T indicator was added to a solution containing calcium and magnesium ions at pH 10.0+ 0.1, the solution became wine-red in colour. If the solution is titrated with EDTA the calcium and magnesium ions are complexed and at the end point the colour of the solution changes from wine-red to blue. Several metal ions can interfere with the titration by producing fading or indistinct endpoints. To minimize these interferences, a sodium sulfide solution is added. The approximate concentration of various ions can be tolerated if sodium sulfide is added. Interfering substances are aluminum 20 mg/l, cadmium 10 mg/l, cobalt 0.3 mg/l, copper 20 mg/l, ferrous ions 5 mg/l, lead 20 mg/l, manganese ion 1 mg/l, nickel 0.3 mg/l, polyphosphate 10 mg/l and zinc 200 mg/l.

Take 10 ml of the sample and to that add 20 ml of deionized water. One ml of buffer solution and 1-2 drop of Eriochrome Black T indicator was also added. Then, the standard EDTA titrant was added slowly with continuous stirring, until the last red tinge of colour disappeared from the solution. The end point of the solution was, normally, blue. The duration of the titration was not extended beyond 5 minutes measured from the time of the addition of the buffer.

Hardness as CaCO3 (mg/l)= (A) xCx1000

V where:

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A= ml of EDTA for titration of sample;

C can be calculated from the standardization of the EDTA titrant and equivalent to

ml of standard calcium solution; and ml of EDTA titrant

V= ml of sample.

Chloride (Cl)

The chloride (Cl

-1

) ion is one of the major inorganic anions present in water and waste water. In

potable water, the salty taste produced by chloride concentrations is variable and dependent on the

chemical composition of water. Some waters containing 250 mg Cl/ l may have a detectable salty

taste if the cation is sodium. On the other hand, the typical salty taste may be absent in water

containing as much as 1000 mg/l when the predominant cations are calcium and magnesium. The

chloride concentration is higher in waste water than in raw water. Along the seacoast, chloride may

be present in high concentration because of a leakage of saline water into water bodies directly or

indirectly. Industrial processes may also increase chloride levels. High chloride content can harm

metallic pipes and structures, as well as growing plants. The method used for this analysis was the

Titration (silver nitrate) standards method.

Representative samples were collected in clean and chemically resistant plastic bottles. The

maximum sample portion required was 100 ml. No special preservative was necessary for the

storage of the samples. Chloride is determined in a natural or slightly alkaline solution by titration

with standard silver nitrate using potassium chromate as an indicator. Silver chloride

quantitatively precipitates before red silver chromate is formed.

Bromide, iodide and cyanide are measured as equivalents of the chloride ion. Main interferences

are the contents of thiosulfate, thiocyanate, cyanide, sulfite, sulfide, Iron (if present >10 mg/l) and

orthophosphate (if present >25 mg/l.) The pretreatment of highly colored or turbid samples is

required. The reagents used for this analysis include:

Standard silver nitrate solution (0.0141 N); and

Potassium chromate indicator

A 20 ml sample was taken in a conical flask. A few drops of K

2CrO4 indicator solution was added and

titrated against a standard solution of AgNO3 (titrant), up to a pinkish yellow end point. 100 ppm NaCl

standard was used to confirm the accuracy.

Concentration of Cl (mg/l) = (A-B) xNx35.45x1000 V

where:

A and B are the volumes of silver nitrate solution required by the sample and blank respectively;

N = Normality of AgNO3 used and

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Sodium (Na) & Potassium (K)

Sodium ranks sixth among the elements in order of abundance and is present in most natural waters. The level of Na may vary from less than 1 mg/l to more than 500 mg /l, Potassium ranks seventh among the elements in order of abundance, and yet it’s concentration in most drinking waters seldom reaches 20 mg/l. Samples for the analysis of sodium and potassium were collected in polyethylene bottles in order to eliminate the possibility of sample contamination, due to the leaching of the glass container. The method used for the analysis of sodium and potassium was the same emission photometric method (Model: PFP-7, JENWAY, UK). The principle of the Flame photometer operation is that compounds are thermally dissociated and are further excited to high energy levels and when these atoms return to their ground state they emit radiation which lies mainly in the specific visible region of the spectrum. Light emitted is proportional to the sample concentration. Detection limits of the instrument for sodium and potassium is <0.2 mg/l. After ignition, the filters select control is set at a proper position. The suction rate of the distilled water should be 2-6ml/minute. Blank and standard solutions of various concentrations were aspirated and fine control was adjusted to have stable positive readings. After blank and standards, samples were aspirated and the results were noted.

Sulfate (SO4)

Sulfate is an abundant ion in the earth’s crust and light concentrations may be present in water due to the leaching of gypsum, sodium-sulfate and shale. High concentrations of sulfate may be present due to the oxidation of pyrite and mine drainage. Sulfates also come from sulfur containing organic compounds and industrial waste discharge. Sulfate concentrations in natural water range from a few mg to several hundred mg per litre. The WHO has established 250 mg/l as the highest desirable level of sulfate. Samples were collected in clean plastic bottles and were stored at 4oC in order to reduce the possibility of the bacterial reduction of sulfate to sulfide in polluted or contaminated samples. The following elements interfere at levels above those concentrations listed below:

Calcium 20,000 mg/l as CaCO3 Chloride 40,000 mg/l as Cl.

Magnesium 10,000 mg/l as CaCO3 Silica 500 mg/l as CaCO3

The method used for analysis of sulfate was the Turbiditimetric Method. The sulfate ion in the sample reacts with barium chloride crystals and forms insoluble barium sulfate turbidity. The amount of turbidity formed is proportional to the Sulfate concentration. UV-VIS Spectrophotometer (Analytik Jena) was used for the analysis.

10 ml of deionized water was taken in a properly washed beaker and 2 ml of Sulphate Buffer solution was added to it followed by an addition of one pinch of Barium chloride crystals. The stirred solution was vigorously for about 1 minute and the absorbance reading was then taken after 5 minutes of reaction time at a wavelength of 420 nm, performed with actual water samples. The concentration was determined from the following equation:

Conc. of sample= Abs. of sample x Conc. of standard/Abs. of standard

To directly measure the concentration of Sulfate in the sample in mg/l, standard solutions of 5,10,15,20,25,30,35 and 40 mg/l were prepared and a Calibration Curve was constructed by using the Software named “Aspect Plus”.

Nitrate (NO3)

Nitrate, a highly oxidized form of nitrogen is commonly present in natural water due to the end product of the aerobic decomposition of organic nitrogenous matter. Significant sources of nitrate are fertilizers from cultivated land, drainage from livestock feed lots and domestic and some industrial waste water. Unpolluted natural water usually contains only minute amounts of nitrate. Excessive concentrations in drinking water are considered hazardous for infants. In their intestinal tract, nitrates are reduced to nitrites, which may cause methaemoglobinaemia.

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Samples were collected in plastic bottles with the addition of boric acid (2 ml/l sample) and then stored at 4oC. Before analysis, the samples were warmed to room temperature and neutralized with a 5.0N sodium hydroxide standard solution. The method used for the analysis of Nitrate was the UV Spectrophotometeric Method.

UV-VIS Spectrophotometer (Analytik Jena) was used for the analysis. 10ml of deionized water was taken in a 25 ml cuvet and to it was added 0.2 ml of 1N HCL. It was applied special correction or blank correction, followed by 10ml standard or sample in cuvet, and HCl was then added to it. The absorbance reading was taken at 220nm to measure the nitrate concentration in the sample and at 275nm to determine the organic interference .Subtracted two times the absorbance reading at 275nm from the reading at 220 nm in order to obtain the corrected reading. To determine the concentration, the following equation is used;

Conc. of sample= Abs. of sample x Conc. of standard/ Abs. of standard

If the Spectrophotometer is set for the concentration determination, it is possible to directly measure the concentration of Nitrate in mg/l from the calibration curve.

Phosphate

Phosphate occurs in natural waters and waste waters as “Phosphates”, classified as the following; o Orthophosphates

o Condensed phosphates (pyro, meta & other polyphosphates)

o Organically bound phosphates Phosphate occurs in the bottom sediments and in biological sludges, both as precipitated, inorganic forms and also incorporated into organic compounds. Phosphorus in total, can be divided

analytically into three chemical types such as; i) Reactive

ii) Acid Hydrolyzable iii) Organic phosphorus

Methods to Determine Phosphate are briefed as following;

Which phosphorus test does the application require

Acid hydrolysable Phosphorus

Reactive Phosphorus Total Phosphorus

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Phos ver 3 with Acid Hydrolysis 0.00 – 5.00 mg/l

0 to 30.00 mg/l 0 to 45 mg/l 0-2.50 mg/l phos Ver 3

Amino Acid method Molybolovanadate Method (Ascorbic Acid)

method

The method used for the analysis of Phosphate was the Phos Ver 3 Ascorbic Acid Method. The

Colorimeter (HACH-DR/890) was used for this analysis. The Colorimeter was turned “ON” and

the program No. 79 PO

4-P was selected. Two cells were filled with 10ml of the sample, one cell is the

sample (for preparation) and other one blank. Blank cell was placed in the colorimeter and zero was pressed. We then added the phosphate powder pillow (PhosVer 3, Cat. 21060-69) in the cell for the preparation sample. Shaking was done for 15 seconds and sample was let to stand for 2 minutes (reaction time), followed by the phosphate concentration value in mg/l by pressing the READ button.

Total Dissolved Solids (TDS)

Measurement for total dissolved solids is a procedure to check the correctness of the analyses and is applicable specifically to water samples for which relatively complete analyses are made. This check does not require additional laboratory analyses. TDS of the water samples was measured in the following way:

Total dissolve solids (TDS) = 0.6 (alkalinity) + Na + K + Ca + Mg + Cl +SO4 + NO3 + F

If the ratio of the calculated TDS to conductivity falls below 0.55, the lower ion sum is suspect and needs to be reanalyzed. If the ratio is above 0.7, the higher ion sum is also suspect and needs to be reassessed. The acceptable criterion is as follows.

Calculated TDS/Conductivity = 0.55 – 0.70

It the ratio of TDS to EC is outside these limits the measured TDS or measured conductivity is suspect and needs to be reassessed.

Trace and Ultra Trace Elements

Fifty eight different trace and ultra trace elements such as Lead, Arsenic, Iron, Fluoride Beryllium, Cadmium, Cerium, Cesium, Cobalt, Chromium, Copper, Niobium, Neodymium, Nickel, Palladium, Praseodymium, Rhodium, Ruthenium, Scandium, Selenium, Samarium, Tin, Strontium, Tantalum, Thallium, Vanadium, Tungsten, Yttrium, Ytterbium, Zinc, Zirconium, Silver, Aluminum, Bismuth, Dysprosium, Erbium, Europium, Gallium, Germanium, Gadolinium, Hafnium, Mercury, Holmium, Indium, Iridium, Lanthanum, Lithium, Lutetium, Manganese and Molybdenum were analyzed. Fifty four of the trace and ultra-trace elements were analyzed with state of the art equipment i.e. with the Inductive Coupled Plasma Spectrometer (ICP Vista Pro). The analytical procedure includes the following steps; 1 Torch alignment using a standard solution of manganese with a concentration of 5 ppm. 2 Wavelength calibration using a multielement standard having 50 ppm potassium and 5 ppm of other elements i.e. Al, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Se, Sr, Zn.

3 Creation of a new worksheet with the selection of the required elements.

4 Calibration with the various multielement standard solutions having desirable concentrations. 5 Analysis of actual water samples.

Distill-dionized water of a high quality (EC<0.3 µS/cm) is used to prepare a blank solution. The volume of concentrated Nitric Acid (65%) is added to distilled water in a ratio to have a blank solution with 2% concentrated HNO3. This blank solution is used for washing as well as for calibration. Samples to be

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Reliability and reproducibility of the analysis were checked by analyzing, blank, standard and pre-analyzed samples after every ten samples. The detection limits of ICP for trace and ultra elements are as following;

Table 3.3 Detection Limits Capability of ICP (Inductive Coupled Plasma Spectrometry) against different elements

Lead (Pb)

Natural water contains more than 5 μg/l of lead. Lead in a water supply may come from an industrial, mine and smelter discharges or from the dissolution of old lead piping. A sample was acidified by the addition of

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2 ml of concentrated HNO3 per liter of the sample prior to storage in a plastic container. The Lead was

analyzed by an Atomic Absorption Spectrometric method using Graphite mode (AAS Vario 6 Analytik Tena AG) using argon gas at a pressure of 3-5 Bars. The graphite tube technique included certain steps such as the installation of a graphite tube furnace unit in the sample chamber; the installation of an autosampler (MPE 50); and the formation of the graphite tube. Optical parameters included the wavelength adjustment at 217 nm. After ensuring the conditions for the lead analysis, the method was loaded. Conditions were given to the autosampler having Diluents (0.5% HNO3) at position 41 and stock (lead standard of 100 ppb at

position 42) solutions of Pb (NO3)2 with 8 ppb concentration, and Mg (NO3)2 with 5 ppb concentration were

used as Analyt modifier. The temperature of the instrument was 900 Co whereas atomization takes place at 1800 C

o

. Calibration was performed with number of standards of known concentration using the stock solution of 100 ppb or as required which will be provided. Working area for the samples was at positions 1-40 on the autosampler. The sample name and sample positions were fed into the software and the analysis was then performed.

Arsenic (As)

Arsenic is a non-metallic element, present naturally in surface and ground water due to the erosion of rocks. It is concentrated in shale, clays, phosphorites, coals, sedimentary iron ore and manganese ores. Aqueous arsenic in the form of arsenite, arsenate and organic arsenicals may result from mineral dissolution, industrial discharges or the application of herbicides. The chemical form of arsenic depends on its source. Inorganic arsenic may originate from minerals, industrial discharges and insecticides, whereas organic arsenic may come from industrial discharges, insecticides and biological action on inorganic arsenic. The toxicity of arsenic depends on its chemical form.

The Atomic Absorption Spectrometer (Hydride Generation mode) was used for the analysis of arsenic in water samples. All samples were analyzed on the HS 55 Mercury/Hydride system, an accessory (AAS, Vario 6 Analytik Jena AG) for the matrix free determination of the hydride forming elements such as As, Bi, Sb, Se, Sn and Te.

The Hydride technique makes use of fact that hydrogen is liberated in the reaction of the weakly acidic sample solutions with sodium boro-hydride, which combines with metal ions to form gaseous hydrides. These are carried to the hot quartz cell by the carrier gas and decomposed by collision processes in a series of steps, until free As atoms are obtained.

For the analysis of arsenic the Atomic Absorption Spectrophotometer (AAS Vario 6 Analytik Jena AG), Mercury/Hydride System HS55 (Analytik Jena AG), and Argon Gas with 99.99% purity were used. The following common reagents were used for the analysis;

i. Sodium borohydride (NaBH4, 98% purity)

ii. Sodium hydroxide, NaOH

iii. Hydrochloric Acid (Concentrated 37% HCl)

iv. Arsenic Standard (1007 μg/ml, As in 2% HNO3, BDH)

In order to make a reducing solution (Reductant), 15 g sodium borohydride (NaBH

4) and 5 g of

sodium hydroxide were dissolved in 500 ml of distilled water. This reagent was then used as a reducing agent for Arsenic analysis.

The HS 55 Mercury/Hydride system, which consisted of a basic unit and the cell unit, was operated and controlled from a PC. The basic unit consists of three accessories. These include the batch module, a single channel-peristaltic pump and gas the valve box. The gas valve box supplied argon gas for scavenging and for transporting the metal hydrides to the system.

The pressure of the argon gas cylinder was adjusted at 3-5 bars. After attaining the necessary temperature (950 oC) a reducing agent was fed by the peristaltic pump. A 10 ml sample was taken into the reaction cell

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and 0.8 ml of concentrated HCl was dispensed into the sample and the reaction cell was adjusted properly at its place. Calibration standards of arsenic with the concentrations (0,10,20,30,40,50 ppb) and (50,60,70,80,90,100 ppb) were prepared. A new method of calibration was developed using these standards under the operation of software, and then the method developed was loaded for the analysis of the actual samples. HS 55 hydride system analyzes the water samples in the following sequences:

Pre-wash time Reaction time Rewash time

The detection limit of this method is 0.1 ppb. Iron (Fe)

Iron is an abundant element in the earth’s crust, but exists generally in minor concentrations in the natural water system. Surface water in a normal pH range of 6 to 9 rarely carries more than 1 mg of dissolved iron per liter. The formation of hydrated ferric oxide makes iron-laden waters objectionable. This ferric precipitate imparts an orange stain to any setting surface including, laundry articles, cooking and eating utensils and plumbing fixtures. Additionally, iron imparts a yellowish colour and a bitter taste to water. This coloration, along with the associated taste and odors can m

References

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