Water quality & its guidelines

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Concept of Water quality& its Guidelines

Presented byGovinda Rokka

May 2, 2023

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Background-Water is an essential nutrient for all forms of life which maintains fluid & electrolyte homeostasis.-Access to safe drinking water is a basic right of human.-(MDG 7) on drinking-water was met globally in 2010.[except by 48 least developed countries] Source:WHO-drinking water

Key facts-Human beings need about (2.5-3) lpd for survival.-Water makes about 60% of human body.-In 2015, 91% of the world’s population had access to an improved drinking-water source, compared with 76% in 1990.-1 in 9 people world wide do not have access to safe and clean drinking water.  -Nearly 1 out of every 5 deaths under the age of 5 worldwide is due to a water-related disease.  Source:https://thewaterproject.org/water_stats WHO-Water Fact Sheet

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Historic Milestones in Drinking Water History• 400 B.C.: Hippocrates emphasizes the importance of water quality to

health and recommends boiling.• 1804: The first municipal water filtration works opens in Paisley,

Scotland.• 1890s: Chlorine is proven an effective disinfectant of drinking water.

1902: Belgium implements the first continuous use of chlorine to make drinking water biologically "safe".• 1974:The Safe Drinking Water Act (SDWA) was established to protect

the quality of drinking water in the U.S. This law focuses on all waters actually or potentially designed for drinking use, whether from above ground or underground sources.

May 2, 2023

History of Water Supply in Nepal

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• While going back to history, the populations of Kathmandu Valley was not high. People in used to take water from the available natural sources near their homes. However, because of rapid population growth the existing water resources were not enough to feed the people and thus, government realized to provide drinking water for the people in the Kathmandu valley and thus established a systematic development of water supply system with the name PANI ADDA (PANI GOSWARA) unit in 2029 BS.

Sources of water in Nepal• Rain water- Purest form of water. Obtained from roof catchments & stored in tanks.• Surface water- Nepal is very rich in surface water consisting of thousands of

rivers,streams,ponds & lakes.• Ground Water- Found abundant in the aquifers of Terai & Kathmandu. But found limited in the

populated hill regions(like Kathmandu) because of the lower permeability of the indurated and crystalline rocks. Eg.wells,springs,spout

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Safe/wholesome/potable water • Free from pathogens (disease causing micro-

organisms) • Contain no chemical compounds or by-products (even

at very low concentrations) that may have health hazards (short term or long term) to the consumers • Free from suspended solids, colour (ie water should be

fairly clear with very low turbidity and very little or no colour), offensive odor and taste • Usable for domestic purposes.

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Status Daily Demand of Water-350 million litresDaily supply of Water- 130 million litres

(fluctuates according to the season)

In this situation,Can we be assure of water quality???

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The study shows that the water sources in the Kathmandu valley are badly contaminated with E.coli & Coliform bacteria.

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Location of River PH TDS(mg/dl) DO(mg/l) BOD(mg/l)

Mahakali at Pancheswor (FWDR) 8.8 110 5 2

Karnali at chisapani (FWDR) 8.9 264 10.5 1.5

Bheri at Chatagaon (MWDR) 7.8 208 9.3 1.1

Seti at Ramghat(WDR) 8.2 222 9.3 2

East Rapti at sauraha (CDR) 7.8 213 8.7 2.5

Arun(EDR) 6.5 200 9.1 2.1

Kankai(EDR) 7.7 60 8.7 2

Mechi (EDR) 8.3 30 8.9 1.8

WHO Guideline 6.5-8.5 100 >5.0 3

Water Quality of Rivers during dry season ,1998

Source:Department of Hydrology and Meterology,1998(CBS:A Compendium on Environment Statistics Nepal,1998

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Arsenic Map of Nepal, WHO 1999

A person suffering from arsenicosis

Guideline valueWHO-10 ppbNepal-50 ppb

More than 90% people consume water from ground water in the Tarai Region .

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Drinking Water Guideline by WHO

1)Acceptability aspects

2)Microbiological aspects

3)Chemical aspects

4)Radiological aspects

Parameter MaxConcentration

Turbidity,PH,color,TDS,electrical conductivity,TDS

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Al 0.2 mg/lNH3 1.5 mg/lCl 250 mg/lZn 3 mg/l

Mn 0.5 mg/lE-coli, Coliform bacteria,virues -

Ar 0.01 mg/lCr 0.05 mg/lPb 0.01 mg/l

F 1.5 mg/l

Cyanide 0.07 mg/l

NO3 50 mg/lCd 0.03 mg/l

Gross α activity 0.1 Bq/l

Gross β activity 1.0 Bq/l

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Group Parameter Unit Maximum Concentration Limits

Physical and chemicals

TurbiditypHColorTaste & OdorTotal Dissolved SolidsElectrical ConductivityIronManganeseArsenicCadmiumChromiumCyanideFluorideLeadAmmoniaChlorideSulphateNitrateCopperTotal HardnessCalciumZincMercuryAluminumResidual Chlorine

NTU

TCU

mg/lµc/cmmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/lmg/l

5 (10)**6.5-8.5*5 (15)**Would not be objectionable100015000.3 (3)**0.20.050.0030.050.070.5-1.5*0.011.525025050150020030.0010.20.1-0.2*

Micro Germs E-ColiTotal Coli form

MPN/100mlMPN/100ml

095 % in sample

Note : * These standards indicate the maximum and minimum limits.** Figures in parenthesis are upper range of the standards recommended.

Sources:-Environment Statistics of Nepal 2008, Government of Nepal, National Planning Commission Secretariat, Central Bureau of Statistics, Kathmandu, Nepal

National Drinking Water Quality Standard

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Status of Bagmati river at different time intervals

15 years ago5 years ago

After Bagmati cleanup campaign

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Human Health & Water quality In developing countries, as much as 80% of illnesses are linked to poor water and sanitation conditions.In Nepal, an estimated 15000 children die each year due to diarroheal diseases, caused by poor environmental sanitation and lack of access to quality water supply.(UNICEF)

Quality water

Proper sanitation

Wellness

Poor Quality water

Poor sanitation

Nevertheless, water quality alone is not enough to ensure the benefits of human health.Three additional requisites must be met: quantity, continuity and reasonable cost.

Illness

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Water Quality and Diarrhoeal Disease

Water Related Disease by Region, 2000

0%

10%20%

30%40%

50%

Mountain (645992) Hill (3230701) Tarai (3239288)

OPD

visit

%

OPD visit as % of total population Water washed disease as % of total OPD visit Water borne disease as % of total OPD visit

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Reasons for water quality Degradation• Haphazard disposal of wastes near the source of water.• Discharge of industrial effluents near the water resource.• Encroachment of water sides .• Watershed degradation and water induced disasters.• Increase in use of chemicals for agricultural purpose.• Presence of leakage and rusting of water pipes.• Presence of sewage pipe nearer to drinking water pipe.

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Solutions• Enforcing compliance of the laws and their effective implementation.• Proper settlement planning and industrialization.• Law enforcement to protect the land from encroachment & effective

implementation of building codes.• Integrated watershed protection & water induced disaster forecasting

system.• Cleaning campaign for the existing rivers should be run frequently.• Putting Sewage pipes as far as possible from the drinking water pipes &

checking the status of water pipes regularly.• Educating people about water quality and its effects on human health.

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List of organizations involved in water quality assessment

• Department of Water Supply and Sanitation(DWSS):To plan the development of water quality monitoring & surveillance program through its Water quality section located in 75 districts.

• National Academy of science and Technology(NAST):The Environment research faculty provides water quality analysis service of water samples from different sources.

• Environment & Public Health Organization(ENPHO): ENPHO laboratory is accredited by Nepal Bureau of Standard and Metrology (NBSM) under the NEPLAS system based on ISO 17025 and is audited for quality control both by internal and external auditors.

• Nepal Environmental & scientific services(NESS): first accredited laboratory in Nepal and since its establishment(1992) it has been providing various analytical services and specialized facilities.

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References

1. WHO-drinking water ,Progress on sanitation and drinking-water Fast facts2.State of Alaska-drinking water history3. Guidelines for drinking water quality,WHO Geneva 2010;4th edth.4.Environmental Statistics of Nepal, 2008 5.WaterAid-Water quality standard and testing policy,20116.Water In Crisis-spotlightNepal

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