A Review of the Pollution Problems in the Wetlands of Kerala and its Management StrategiesRajinikanth, R Sudhakar, G and Deepa Elizabeth RajanCenter for Water and Environmental Studies,Department of Civil Engineering,Kumaraguru College of Technology,Coimbatore – 641 006, Tamil Nadu, India

Wetland systems of Kerala, as elsewhere in India are subjected to acute

pressure of rapid developmental activities and indiscriminate utilisation of

land and water. As a result, the system is being destroyed, especially in the

tropics at an alarming rate of one percent per year.

A study was undertaken in two wetlands of Kerala namely Kumarakom and

Budhathan Kattu to assess the water quality and to suggest appropriate

mitigation measures based on the degree of pollution. These wetlands serve

as a suitable breeding and roosting place for wetland birds and diverse

microorganisms. Due to urbanisation and other developmental activities in

and around these wetlands, there have been changes in water quality, aquatic

flora and fauna, which are reflected in the changes of all biotic components

of the environment, including human beings. To elucidate the changes

taking place in these two wetlands, water quality monitoring and to assess

the dependency on these wetlands, a socio-economic survey is being

conducted (September 2002 - till date). The present paper discusses the

current status of these wetlands, along with suitable mitigation measures that

has to be adopted for continued sustenance of these ecosystems

1.0 INTRODUCTION

Wetlands are an integral part of river basins or extension of sea and are

among the productive ecosystems of earth. Wetlands constitute about 6.4

% of earth’s surface or about 8.6 million sq. km (Clare Shine and Cyrille de

Klemm, 1999). Wetlands are those areas that are inundated or saturated by

surface or groundwater at a frequency and duration sufficient to support, and

that under normal circumstances do support, a prevalence of vegetation

typically adapted for life in saturated soil conditions. As far as the state of

Kerala is concerned, the wetland environment of these humid tropics has

given shape to its economic, social, and environmental features. It is after

the Ramsar convention (Ramsar, 1976) that the wetlands all over the world

have received greater attention from scientists, researchers and planners.

1.1 Wetland systems of Kerala

Kerala has a high density of population (750 persons/sq.km) and has number

of rivers, canals, ponds, natural and artificial lakes, backwaters and

mangroves. Kerala has 32 natural and 2,121 artificial wetlands with water

spread area of about 24,329 and 2,10,579 ha respectively (Chatrath, 1992).

The Kuttanad, Kole and Pokkali areas in Kerala with a number of

backwaters and extensive paddy fields, lakes, estuaries etc., constitute the

important wetland systems. The Sasthamkotta wetland of Kerala spread over

375 hectares are wetlands of national and international importance in India.

Wetlands play a major role in controlling floods, ensure protection from

wave erosion, recharge aquifers and they are winter habitats for migratory

birds. A little over 25 plant varieties and 22 animal groups in the country's

wetlands figure in the list of endangered species. Among the other points

highlighted by the study is that the actual forest cover of Kerala is not more

than 10,336 sq. km in spite of its geographical area having a spread of as

much as 38,863 sq. km (Gopal et al., 1993). This reveals the extent of

deforestation, which the State has suffered over the years.

When the situation of this state is reviewed, it could be observed that Kerala

is among the wettest regions of the world, with an average annual rainfall of

around 3000 mm. But within a few months, most of it drains off into the sea

via Kerala’s 44 rivers. Then follows the months of shortage of water.

According to the statistics provided by the Ministry of Environment and

Forests, Government of India, the wetlands in Kerala cover an area of 6.5

lakh ha.

1.2 Wetlands Scenario in Kerala:

Wetlands of Kerala have been drained and transformed by anthropogenic

activities like unplanned urban and agricultural development, industrial sites,

road construction, impoundment, resource extraction, dredge disposal

causing substantial economic and ecological losses in the long run.

Encroachment and reclamation of wetlands for farming are the threats faced

by the rapidly diminishing area of wetlands in Kerala. An aspect of the

encroachments resulting from agricultural expansion is that while this may

add to the country's grain production, the shrinking of the wetlands will

eventually have a negative impact on agricultural output itself. About

3,50,000 ha of land under wetland ecosystem is put under agriculture. They

are mainly used for paddy cultivation and aquaculture. The wetlands of

‘Pokkali, ‘Kuttanad’ and ‘Kole’ are examples of purposeful human

interventions whereas irrigated as well as rain-fed rice cultivation are widely

practiced in midlands and highlands. A number of industries situated on the

bank of rivers and backwaters empty their effluents into the wetland system

and thus contribute to pollution. The quantum of pollution caused by the

discharge of untreated sewage into wetland system is also alarming. A major

source of pollution of Vembanad lake is the domestic sewage generated in

the urban areas of Alappuzha and Kochi. These threats will finally cause

ecological imbalance leading to deleterious effects on living resources,

hazards to human health, hindrance to aquatic activities, impairment of

water quality and reduction of amenities (Unnithan et al., 1976).

The present paper discusses the current status of two wetlands namely

Kumarakom and Budhathan Kattu, along with suitable mitigation measures

that has to be adopted for enduring sustenance of these ecosystems

2.0 OBJECTIVES

The main objectives of the study was

To assess the water quality in Kumarakom and Budhathan Kattu

wetlands;

To evaluate the level of dependency of the people living in the

surrounding areas on these wetlands by conducting socio-economic

survey; and

To suggest appropriate mitigation measures based on the degree of

pollution and level of dependency.

3.0 STUDY AREA

Kumarakom is part of the vast backwater labyrinth called Vembanad

Backwater (Kayal), which is the largest of the series of coastal wetlands

of Kerala. Kumarakom is situated near Kottayam, 80 Km from Kochi by

road. Kumarakom backwater extends over an area of about 794 sq Km.

Most of the extensive water body, apart from a central portion has been

converted to paddy fields, coconut groves and human habitats over the

last century.  Budhathan Kattu is situated near Ernakulam, which covers

villages like Imanam, Pindimana etc., of Kothamanyalam Taluk. These

wetlands are forming several island of ecological significance especially

to bird life. The ten most abundant species recorded are the Lesser

Whistling teal, Little Cormorants, Whiskered Terns, Pond Herons,

Intermediate Egrets, Indian Shag, Cattle Egrets, Purple Heron, Little

Egret, and the Cotton Teal (Kalypso Adventures of Kerala).

Fig 1: Kumarakom backwaters (part of a Vembanad

Backwater systems)

4.0 METHODOLOGY

4.1 Sampling

Water samples were collected from various representative sites to

assess their characteristics and changes in their quality. These

representative samples were collected between 7.00 and 8.00 A.M

using polyethylene cans (pec) and were handled in such ways that no

significant changes in composition occurred before the tests were

performed. Four samples were collected in various locations of each

wetland and they are as follows:

Water sampling location for Kumarakom wetland:

Sample Number Location S 1 North East Direction S 2 South DirectionS 3 West directionS 4 Central part of wetland

Water sampling location for Budhathan Kattu wetland:

Sample Number Location S 1 North direction S 2 South East directionS 3 West directionS 4 Central part of wetland

4.2 Water quality analysis Various physico-chemical and biological parameters (mentioned in

Table 1 and Table 2) for the representative water samples were

analysed according to the customary methods provided by American

Public Health Association (APHA). The obtained values were

compared with the permissible limits prescribed by NEERI’s Indian

Standard Specifications (IS: 2490 – 1982).

4.4 Socio-economic survey

Socio-economic survey was done to assess the level of dependency of

local communities on the resources and benefits provided by these

wetlands (Edward B Barbier, 1997). The household survey was done

through conducting interviews with the local people by randomly

selecting the houses in and around these wetlands. Specially prepared

questionnaire format was used for this survey.

5.0 RESULTS AND DISCUSSION Table 1 and 2 gives the quality status of Kumarakom backwaters and

Budhathan Kattu backwaters respectively for the month of September 2002.

Table 3 gives an idea about the comparison of quality determining variables

with that of permissible limits provided by Indian Standard Specifications

and World Health Organizations (WHO).Table 1: Water quality analysis results of Kumarakom backwaters

PARAMETERS / SAMPLE NO. S 1 S 2 S 3 S 4

pH 7.2 7.3 7.3 7.4Electrical Conductivity (ms/cm) 0.2 0.19 0.17 0.19Chlorides (mg/l) 79 75 79.4 76.2Hardness (mg/l) 85 86 110 95Magnesium (mg/l) 29.4 27 42 33Calcium (mg/l) 55.6 59 68 62

Sulphates (mg/l) 94 63 123 90Nitrates (mg/l) 2 1.5 3.5 2.9Sodium (mg/l) 63.7 62.2 75.5 58.5Potassium (mg/l) 2.7 2.8 2.9 2.3Total Solids (mg/l) 130.2 132 141.2 139.2Total Dissolved Solids (mg/l) 77.9 85 89.3 83.2Total Suspended Solids (mg/l) 30.9 47 51.9 56Dissolved Oxygen (mg/l) 2.89 3 2.65 2.95Biological Oxygen Demand (mg/l) 12.05 12.09 13.98 11.98

Total Coliform Present PresentPrese

nt Present

Faecal Streptococcus Present PresentPrese

nt Present

Table 2: Water quality analysis results of Budhathan Kattu backwaters

PARAMETERS / SAMPLE NO. S 1 S 2 S 3 S 4

pH 6.9 6.8 7.1 7.2Electrical Conductivity (ms/cm) 0.3 0.22 0.31 0.32Chlorides (mg/l) 40 36 28 30Hardness (mg/l) 40.25 48.2 45.2 48.6Magnesium (mg/l) 19.2 12.8 16 12Calcium (mg/l) 21.05 35.4 29.2 36.6Sulphates (mg/l) 80 78 77 65Nitrates (mg/l) 0.9 1 1.1 0.95Sodium (mg/l) 21.6 10 10.6 10.5Potassium (mg/l) 1.9 1.6 1.8 1.5Total Solids (mg/l) 100 99 105 90Total Dissolved Solids (mg/l) 69 71 67 65Total Suspended Solids 31 28 38 25

(mg/l)Dissolved Oxygen (mg/l) 4.2 4.1 3.8 3.9Biological Oxygen Demand (mg/l) 4.95 5.12 5.85 5.78

Total Coliform Slightly present Nil Nil Nil

Faecal StreptococcusSlightly present Nil Nil Nil

Table 3: Comparison of variables with that of permissible limits Parameter Kumara

komBudhathan Kattu

Permissible

limit

pH 7.2 – 7.4 6.8 – 7.2 6.5 – 8.5 Electrical Conductivity (ms/cm)

0.2 – 0.19

0.22 –0.32

50 – 1500 s/cm

Chlorides (mg/l)76.2 – 79

28 - 40 250 mg/l

Hardness (mg/l)85 – 110 40.25 –

48.6300 mg/l

Magnesium (mg/l)27 – 42 12 –

19.2 30 mg/l

Calcium (mg/l)55.6 – 68

21.05 – 36.6

75 mg/l

Sulphates (mg/l) 63 – 123 65 - 80 150 mg/lNitrates (mg/l) 1.5 – 3.5 0.9 – 1.1 45 mg/l

Sodium (mg/l)62.2 – 75.5

10 – 21.6

200 mg/l

Total Dissolved Solids (mg/l)

77.9 – 89.3

65 - 71 500 mg/l

Total Suspended Solids (mg/l)

30.9 – 56

28 - 38 100 mg/l

Dissolved Oxygen (mg/l)

2.65 –2.95

3.8 – 4.2 4 mg/l min

BO D (mg/l)11.98 – 13.98

4.95 – 5.85

2.0 max

Total Coliform Present ND-

Present Nil

Faecal Streptococcus

Present ND- Present

Nil

The Fig 1 gives an idea about the comparative water quality analysis values between Kumarakom and Budhathan Kattu wetlands at different sampling sites.

The field and laboratory investigations (physico-chemical and biological

analysis) show that Dissolved Oxygen, Biological Oxygen Demand (BOD),

Total Coliform and Faecal Streptococcus concentrations of Kumarakom

wetland surpasses the permissible limits set by ISS (IS: 2490 – 1982) [Refer

Table 3] whereas the concentrations of the above-mentioned variables are

comparatively less in the case of Budhathan Kattu wetland. The higher

concentrations of variables are mainly because of improper watershed

management in the surroundings of Kumarakom wetland systems. Also the

agricultural developments have resulted in the input of large quantities of

agrochemicals and pesticides in the Kumarakom wetland bodies (Nair and

Unni, 1993). The slums encroached into the peripheral wetland areas of

Kumarakom water bodies have also contributed to its pollution and

deterioration. About 30 to 40 % of the wetland marginal areas are

encroached for human settlements and agricultural activities so far. These

stresses are comparatively less in the case of Budhathan Kattu.

Table 4 shows the dependency of the people residing closer to Kumarakom and Budhathan Kattu wetlands respectively.

Table 4: Socio-economic details PURPOSE

KUMARAKOM

BUDHATHA

N KATTU(i) Direct use

Domestic

Drinking Bathing

Washing Flushing

Animal consumption Agricultural

Fishing

Fodder

Energy

(ii) Indirect Use Ground Water

recharge

Storm protection

Bird-diversity

Cultural and Heritage values

Water quality (through house hold survey)

Not fit for drinking (as water borne diseases like dysentery,

fever, skin irritation, cholera etc., were recorded especially in the months February and March)

The socio-economic survey in these regions shows that the local

communities are very much dependant on both the wetlands especially for

washing, fodder , fishing, agricultural and plantations (rubber, coconut etc.),

groundwater recharge, fodder for domestic animals and energy. This study

further shows that Budhathan Kattu waters are used for drinking and bathing

purposes unlike Kumarakom water-usage practices. The interviews with the

local people who still earn their livelihood from the resources of these

wetlands have shown that 40 per cent of the people belonging to different

communities are keenly conscious of the interdependence of man and his

environment and that their livelihood patterns not only blend harmoniously

with the ecosystem but also that they utilise the various resources prudently

and are self-reliant i.e., without depending on the inputs from outside.

6.0 CONCLUSION

The field and laboratory investigations show that Dissolved Oxygen,

Biological Oxygen Demand (BOD), Total Coliform and Faecal

Streptococcus concentrations of Kumarakom wetland surpasses the

permissible limits set by ISS (IS: 2490 – 1982) whereas the

concentrations are comparatively less in the case of Budhathan Kattu

wetland.

The elevated concentrations of variables are mainly because of improper

watershed management in the surroundings of Kumarakom wetland

systems. Also the agricultural developments have resulted in the input of

large quantities of agrochemicals and pesticides in the Kumarakom

wetland bodies (Nair and Unni, 1993). The slums encroached into the

peripheral wetland areas of Kumarakom water bodies have also

contributed to its pollution and deterioration. These stresses are

comparatively less in the case of Budhathan Kattu.

The results of socio-economic survey conducted in these regions shows

that the local communities are very much dependent on both the

wetlands for their livelihood especially for bathing, washing, fodder ,

fishing, agricultural and plantations (rubber, coconut etc.), groundwater

recharge, fodder for domestic animals and energy.

About 30 to 40 % of the wetland marginal areas are encroached for

human settlements and agricultural activities.

On seeing these tragic and challenging situations there is a pressing need

to relook into the dwindling wetland resources and evolve suitable

conservation and restoration strategies to arrest these deteriorating

ecosystems and to maintain the ecological balance of the fragile

ecosystem and to rehabilitate wetlands with the healthy and productive

wetland ecosystem as the target or vision to be achieved. The following

mitigation measures are recommended for better ecological sustainability

and their long-term sustenance by managing and conserving the

watershed from point and non-point source of pollution that drained in to

it.

Best Management Practices (BMPs) like pollution prevention, extended

detention dry basins, Constructed wetlands and Grassed swales (EPA,

1999) are suggested in managing point and non-point source of pollution.

This along with regulations and planning for wildlife habitat and fishes

helps in arresting the declining water quality and the rate of loss of

wetlands.

Prevention of encroachments through legal action along with public

participation. Restored wetlands could be used for recreational purposes

such as boating and fishing; and for agricultural purposes, with the

condition that care should be taken to prevent point and non-point

source of pollution that drains in to it.

The long-term solution to the problem of protecting wetlands lies in

educating people. Unless people realise the need to safeguard wetland

ecosystems, and are aware of how they can contribute to this effort, there

is little hope for the survival of these ecologically- valuable and

vulnerable habitats.

7.0 SCOPE FOR FURTHER STUDY

The preliminary investigations on these two wetlands has paved the way to

do the following future studies:

Monitoring the quality and quantity status of these wetlands for various

seasons;

Quantifying the wetlands resources in terms of Rupees;

Biological and microbiological investigations;

Characterisation and classification of Wetland soils;

Fertilisers and Pesticides study;

Flora of wetlands; and

Bird diversity study.

8.0 ACKNOWLEDGEMENT

The authors are thankful to Prof. K.Arumugam, Correspondent, Dr.

K.K.Padmanabhan, Principal Dr. K.Swaminathan, H.O.D of Civil

Engineering Department and Prof. R.Krishnamoorthy, Dean (Academic),

Kumaraguru College of Technology, Coimbatore for their constant support

and encouragement. We sincerely acknowledge the suggestions,

encouragement and support rendered by Prof.Joseph.V.Thanikal. We also

acknowledge the co-operation of Ms. Vidhya, Mr. Mayil Durai, Ms. Uma

Devi, Mr.Kayed Xoher and Ms. Nisha Kamurudeen in analysing the water

samples.

8.0 BIBLIOGRAPHY

American Public Health Association (APHA), American Water Works

Association (AWWA) and Water Pollution Control Federation (WPCF),

1985. Standard Methods for the examination of water and wastewater.

Sixteenth edition, Ed. by Arnold E.Greenberg, R. Rhodes Trussell and

Lenore S. Clesceri, Washington DC.

Brij Gopal., Ilkowska., A.H. and Wetzel, R.G., (Ed.) 1993. Wetlands and

Ecotones. National Institute of Ecology, New Delhi.

Chatrath, K.J.S., 1992. Wetlands Of India-Major threats faced by

wetlands of India and their conservative measures. Ashish Publication

House, New Delhi, PP.22-32.

Clare Shine and Cyrille de Klemm., 1999. IUCN Environmental Policy

and Law paper No. 38. Published by IUCN, Gland, Switzerland and

Cambridge, UK in collaboration with IUCN Environmental Law Centre,

Bonn, Germany, PP. 3-21.

Edward B Barbier., Mike Acreman and Duncan Knowler., 1997.

Economic Valuation of Wetlands - A Guide for Policy Makers and

Planners. IUCN Publication Unit, Ramsar Convention Bureau Gland,

Switzerland, PP 1- 46, 81- 97 and 110- 127.

Environmental Protection Agency (EPA)., 1999. Protecting natural

wetlands - A guide to storm water Best Management Practices. U.S.

Jayson, E.A., 2002. Avifauna in the Wetlands of Kerala. Kerala Forest

Research Institute, Thrissur, Kerala.

Nair and Unni., 1993. Environmental Status Report. Kerala State

Pollution Control Board, Kerala.

Ramteke, D.S and Moghi, C.A., 1988. Manual On Water And

Wastewater Analysis. National Environmental Engineering Research

Institute, Nehru Marg, Nagpur.

Unnithan, R.V., Vijayan, M and Remani, K.N., 1976. Organic Pollution

in Cochin Backwaters. Ind. J.Mar. Sci.4, PP 39 – 43.