water quality issues in swm by sudhakar m....

WATER QUALITY ISSUES in SWM

By Sudhakar M. Rao

IISc

Bangalore

Introduction

Two third of Our planet earth is water. But 97% is saline .Out of

the balance 3%, 2.1% is trapped into Glaciers and deep sea. Only 0.7% fresh water is available for human consumption

Why Water is so Important? • Universal solvent so essential component for - Domestic Applications - Agricultural Applications - Industrial Applications - Propagation of life particularly aquatic life and plants • For the each application water requires a defined quality.

Sudhakar Rao-IISc

Water Resources In India

Total Water Availability

1869 BCM

Surface Water

Availability 690 BCM

14 Major River Basins

Ground Water

Availability 432 BCM

68% remains untapped

Sudhakar Rao-IISc

Domestic & Industrial use

70 BCM

Agriculture

330 BCM

Replenishable Ground Water

Resource

432 BCM

Water Quality Issues

• Water Quality stresses:

- Natural sources

- Anthropogenic Sources

• Fluoride, arsenic, iron are examples of

contamination from natural sources

• Anthropogenic sources causes much more

stress in a very wide range of parameters

and to a large magnitude

Water quality issues:

Domestic Applications: • In domestic applications water is used for - drinking, - bathing, - washing, - waste disposal etc. • Quality Norms have been prescribed for each

application.

• Why Not to maintain Best Quality?

• Lot of efforts and cost is involved in maintaining the water quality for each application


Industrial Applications: In Process as solvent or as additive For fermentation As steam for heating applications in Boilers For cooling For cleaning operations For waste transport & disposal There is a scope for recycling the water for many downstream

quality applications and finally for reuse for horticulture etc.


Agricutural/ Rural Applications: - For land preparation - Irrigation

- For applying fertilizers and pesticides

- Livestock rearing

The important water quality parameters are salinity (TDS) , SAR. Also pesticides and heavy metals if accumulate may go to food chain

Water Quality Issues

• Life Propagation:

• For aquatic life for respiration

• For Plants for transport of food materials

• For microbial population for growth

• Dissolved Oxygen is the most important

parameter for life propagation

• Toxic materials could also be fatal for survival

Threats to water Quality

Microbiological pollution,

Organic pollution,

salinity,

Heavy metal pollution,

Pollution by toxic inorganic compounds (Nitrate, Nitrite, Fluoride, Phosphates, Sulphides)

Pollution by Toxic organics like phenols, AOx, PAH

Thermal pollution

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Quality

deterioration

Domestic

pollution

Agricultural

pollution

Industrial

pollution

Geogenic

contamination

Disposal of

wastes,

leaching of

sewer

materials,e

tc.

Leaching

of

nutrients,

pesticides,

fertilisers,

etc.

Disposal of

effluents in

streams or

on land

Arsenic

Fluoride

Iron

Nitrate

Salinity

Issues Impacting SWM in Indian Context:

Water Quality Issues Catchment-Degradation Gender and Class

Surface water Groundwater

Most important causes of Water Pollution are:

(a) Unplanned development without adequate attention to sewage and waste disposal.

(b) Industrialization without provision of proper treatment and disposal wastes and affluent.

(c) Excessive application of fertilizers for agricultural development.

(d) Over-irrigation intrusion due to excessive pumping of fresh water in coastal aquifers. This “over-exploitation” mainly accounts for seawater intrusion.

18-19 % of rural and 75-81 % of urban inhabitants have access to adequate sanitation facilities (WRI 2000).

Organized sewerage systems range from 35 % in class IV cities to 75 % in class I cities

Of the total wastewater generated in metro cities, barely 30 % is treated before disposal.

Significant increase in MSW generation. Per capita MSW generation ranges from

100 g in small towns to 500 g in large towns

Annual production of solid waste in India has been estimated at 2,000 million tons

(MOWR 2000).

Domestic Pollution.

Industrial Pollution

Industrial sector accounts for 3% of the annual water withdrawals in India- contribution to water pollution, particularly in urban areas, is considerable.

Wastewater generation from this sector estimated at 55,000 million m3 per day, of which 68.5 million m3 are dumped directly into local rivers and streams without prior treatment (MOWR 2000).

Agro based industries, Distilleries, Sugar mills and Paper mills - Organic pollution Chemical industries, steel plants, pharmaceuticals and tanneries etc – TDS and Toxic chemicals

Lack of cost-effective technologies to treat certain wastewater types - containing

high organic load/dissolved solids and chemicals like lignin, phenols, cyanides,

pesticides, PAH, PCB etc. or toxic substances which are not easily degradable is

impacting their treatment

Groundwater Overuse and Contamination

Groundwater accounts for over 80% of the rural domestic water supply and 45% of the irrigation water supply in India (World Bank 1999, MOWR 2000).

Currently over 10% of blocks classified by the Central Groundwater Board have been identified as being over-exploited and blocks where exploitation is beyond the critical level have been increasing at a rate of 5.5% each year (World Bank 1999).

Nature of

quality problem

Number of

affected

habitations

Approximate

population at

risk (million)

Affected regions

Excess Arsenic

(0.05-3.2 mg/L)

5,029 25 79 blocks of 8 districts (Bardhaman, Hoogli, Howrah, Malda, Murshidabad, Nadia,

North and South 24 Parganas) of West Bengal, parts of Bhojpur and Patna districts

of Bihar and Ballia district of Uttar Pradesh, parts of Rajnandgaon district of

Chhattisgarh and parts of Assam

Excess Fluoride

(1.5-48 mg/L)

36,988 71 (a) Kerala, Jammu & Kashmir, West Bengal, Orissa, Assam, Bihar and Delhi with

less than 30 per cent of the districts affected.

(b) Punjab, Haryana, Madhya Pradesh, Karnataka, Uttar Pradesh, Tamil Nadu,

Chattisgarh and Maharashtra with 30-70 per cent of the districts affected.

(c) Rajasthan, Gujarat and Andhra Pradesh with 70-100 per cent of the districts

affected.

Excess Iron (1-

20mg/L)

1,38,670

- Prevalent mostly in hilly regions, parts of Assam, Agartala, Bihar, Orissa,

Rajasthan, Tripura, West Bengal, Uttar Pradesh, Punjab, Maharashtra, Madhya

Pradesh, Chhattisgarh, Jharkhand, Tamilnadu and Kerala.

Excess Nitrate

(50-1000 mg/L)

13,958 842.54 Parts of Uttar Pradesh, West Bengal, Rajasthan, Madhya Pradesh, Chandigarh,

Punjab, Haryana, Delhi, Bihar, Maharashtra, Karnataka, Kerala, Orissa, Jammu &

Kashmir, Himachal Pradesh, Gujarat, Tamil Nadu and Andhra Pradesh

Excess Salinity

(Inland and

coastal)

(2000-27000

mg/L)

32,597 - Inland salinity: Inland salinity in ground water is caused due to geogenic sources.

The problem of inland salinity has been observed in arid and semi arid regions of

Rajasthan, Haryana, Punjab, and Gujarat with limited extent in the states of Uttar

Pradesh, Delhi, Karnataka, Maharashtra, Madhya Pradesh and Tamilnadu.

Electrical conductivity in these areas exceeds 4000 micro Siemens/ cm.

Coastal salinity: Problem of coastal salinity in ground water that is caused due to

excessive exploitation of ground water has been observed in Mangrol - Chorwad

areas and Coastal Saurashtra of Gujarat, Minjur area in Tamilnadu, Pondicherry

coast, parts of Orissa, Andhra Pradesh and Kerala coast.

Other reasons

(Heavy metals,

Pesticides,

Fertilizers, etc.)

25,092 - Parts of Andhra Pradesh, Assam, Bihar, Goa, Gujarat, Haryana, Himachal Pradesh,

Karnataka, Kerala, Madhya Pradesh, Maharashtra, Meghalaya, Orissa, Punjab,

Rajasthan, Tamil Nadu, Uttar Pradesh, West Bengal and NCT of Delhi

Total 2,52,334

Surface water issues (river, pond, tanks,

lakes etc)

• Change in physical characteristics (turbidity,

TSS, temperature)

• Toxic pollutants (organics, recalcitrant materials,

heavy metals)

– Point sources

– Diffuse sources

– Atmospheric transport and deposition

• BOD :Unpolluted natural waters < 5 mg/L BOD.

• Dissolved Oxygen DO levels < 3 ppm are stressful to most aquatic organisms.

• DO levels < 2 ppm will not support fish.

• DO = 5-6 ppm is required for growth

and activity of most aquatic organisms.

Faecal Coliforms: Drinking water-must be absent

PATHOGENIC MICRO-ORGANISMS

Analysis:

• Coliform bacteria is an indicator of faecal pollution

• Present in large numbers in faeces of

healthy & sick individuals

• Easily determined in laboratories

• Expressed as most probable number:

MPN/100mL

Fluoride pollution

Nitrate pollution

Indiscriminate disposal

of sewage and

garbage

Salt water intrusion

Arsenic pollution

GROUNDWATER

POLLUTION

CRITICAL PARAMETERS

• Nitrate > 45 mg/L - Leads to cancer,

and Blue Baby Syndrome

• Fluoride> 1.5 mg/L - Leads to Dental

fluorosis, skeletal fluorosis

• T H > 600 mg/L - Effects on domestic

use

• T D S > 2000 mg/L - Causes gastro

intestinal irritation

• Iron > 1.0 mg/L - Promotes iron

bacteria

Impacts of Urbanization • High organic pollution from huge quantity of

treated/untreated Sewage depletes oxygen from water bodies.

• Microbial pollution- water becomes unfit for human consumption particularly potable use

• Indiscriminate dumping of domestic solid wastes- generates

• a) leachate- affects ground water quality b) run off - affects surface water quality. Biomedical waste from hospitals causes microbial

pollution Increasing urbanization have induced extraction of

more quantity of ground water and may be one of the reasons for earth quake.

Impacts of Industrialization

• Water bodies are getting contaminated with toxic organics/ inorganics

• Toxic metals gets bioaccumulation and enters into food chain

• Persistent organic matter causes severe diseases . Many of them are carcinogenic

• High organic matter causes depletion of oxygen from water bodies

High TDS causes salinity of soil and make it unfit for agriculture

Industrial activities as issues

• Pharmaceuticals High COD and TDS • Pesticides Persistent Organic compounds,

High COD and TDS • Chemical Manufacturing Industries High TDS, COD, Toxic metals • Textile industries Toxic dyes and high TDS

• Tanneries Chromium, BOD, COD, TDS

• Paper and Pulp Industries Colour, BOD and AOX

• Distilleries Color, BOD and TDS

• Petroleum refineries Oil and Grease

• Chlor- alkali industry Hg, Chlorine and high TDS

Impact of Agricultural activities

• Utilization of Chemical Fertilizers (like urea, DAP, potash salts)- High N and P contents lead to eutropication followed by turbidity in lake and waterbodies

• Utilization of Pesticides(organo-chlorine and organo-phosphorous compounds) contaminate the aquatic system.

• The pesticides, herbicides and insecticides applied are highly persistent in nature.

Areas of Focus

Water Quality

Impact of geogenic stresses on groundwater bodies

Impact of anthropogenic stresses on ground water

bodies

Groundwater Contamination (Drinking water)

Geogenic sources; Arsenic, Fluoride, Iron & Salinity

Anthropogenic sources:Nitrates, Pesticides, Organics, Heavy metals,

Microbial contamination

Sudhakar Rao-IISc

High levels of fluoride in drinking water ( > 1.5

mg/L ) leads to dental and skeletal fluorosis.

Problem is severe where ground water is the

major source of drinking water.

Indian standard specifies ( IS 10500: 1991)

desirable and permissible limits of fluoride in

drinking water as 1.0 and 1.5 mg/L.

Why is fluoride in drinking water

an environmental problem ?

Introduction

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0

1

2

3

4

5

6

Lead Fluoride Arsenic

Relative toxicity

Based on LD50 data from Robert E. Gosselin et al,

Clinical Toxicology of Commercial Products 5th ed., 1984

5 Extremely toxic

4 Very toxic

3 Moderately toxic

2 Slightly toxic

1 Practically nontoxic

Toxicity of fluoride compared to lead and arsenic

Fluorine is a colorless

and odorless natural

pollutant

Introduction

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Health Effects

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Health impacts from long term use of

fluoride bearing water :

1.5 to 4.0 mg/L – Dental Fluorosis

> 4.0 mg/L – Dental and skeletal fluorosis

> 10 mg/L – crippling fluorosis

Health Effects

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Health Effects

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Occurrence in Ground Water

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Fluorides in ground water derives mainly from dissolution of natural minerals in the rocks and soils with which water interacts.

Most common fluoride bearing minerals are Fluorspar / Calcium fluoride (CaF2)

Apatite / Rock phosphate [Ca5F (PO4)3]

Cryolite / Sodium aluminum fluoride (Na3AlF6)

Dominant factors influencing fluoride build up in water are : Geology, contact time with fluoride minerals, ground water chemical composition and climate.

Occurrence in GW

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70 100 % affected

40 70 % affected

10 40 % affected

Endemic fluorosis is a

public problem in India

Almost 60-65 million

people drink fluoride-

contaminated

groundwater.

The number affected by

fluorosis is estimated at

2.5-3.0 million.

Areas endemic to fluorosis in India

Occurrence in GW

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According to latest information at least 20 states of

India, including the new creations Uttaranchal,

Jharkhand and Chattisgarh are endemic to fluorosis.

Andhra Pradesh, Gujarat, Rajasthan 70 100 %

districts are affected

Bihar, Punjab, Haryana, Karnataka, Maharashtra,

Madhya Pradesh, Tamil Nadu, Uttar Pradesh, some

parts of Delhi 40 70 % districts are affected

Assam, Kerala, Orissa, West Bengal, Jammu &

Kashmir 10 40 % districts are affected

Occurrence in GW

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Fluoride concentration in 15 districts of Karnataka

27.87

44.92

13.77

7.54 4.26 3.93

0

10

20

30

40

50

60

Perc

en

t

1-2 2-3 3-4 4-5 5-6 6-8

Fluoride concentration (mg/L)

Occurrence in GW

GW Chemistry

Mamatha & Rao, 2009, Env. Earth Sci Tumkur

Anthropogenic Contamination of GW resources

Unplanned urban development without adequate attention to

sewage and waste disposal.

(b) Industrialization without provision of proper treatment and

disposal wastes and affluent.

(c) Excessive application of fertilizers for agricultural

development.

(d) Over-irrigation intrusion due to excessive pumping of fresh

water in coastal aquifers. This “over-exploitation” mainly

accounts for seawater intrusion.

Pollution-Sewage

18-19 % of rural and 75-81 % of urban inhabitants have access to adequate sanitation facilities (WRI 2000).

Organized sewerage systems range from 35 % in class IV cities to 75 % in class I cities

Of the total wastewater generated in metro cities, barely 30 % is treated before disposal.

General Background

General Background

Inner town series, Nitrate

0

50

100

150

200

250

300

350

400

450

M-1

14

M-1

15

M-1

16

M-1

17

M-1

18

M -

119

M -

120

M-1

21

M-1

22

M-1

23

M-1

24

M -

225

M-2

26

M-2

27

M-2

28

M-2

29

M-2

30

M-2

31

M- 2

33

M-2

34

M-2

35

M-2

36

M-2

44

M-2

45

M-3

00

M-3

12

M-3

13

M-3

14

M-4

00

M-4

01

M-4

02

M -

403

M-4

04

M-4

05

M-4

06

M-4

07

M-4

08

M-4

10

M-4

11

M-4

12

M-4

13

M-4

14

M- 4

15

M-4

17

M-4

19

M-4

21

M-4

22

Location

Nit

rate

, p

pm

Permissible limit = 45 ppm

Drinking water

classification

Remedies for the issues

• Sustainable development • Adopting waste minimization (Conserve, Recycle and Reuse) • Cleaner technologies in industrial sectors • Biofarming i.e. Applications of bio-fertilizers and bio-

pestcides) in place of chemical fertilizers and pesticides. • Scientific management of hazardous wastes and following

environmentally sound recycling like lead from Batteries, Oil from Used/waste Oil .

water quality issues in swm by sudhakar m....

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