The document summarizes environmental problems and management aspects of the Vembanad Kol wetland system in Kerala, India. It begins with background on wetlands and an introduction to the Vembanad Kol system. It then discusses the wetland's physical characteristics, ecological significance, economic potential, and history of interventions. Major problems are outlined such as the impacts of physical barriers, sand mining, tourism, industrialization, and more. Potential management strategies are proposed, including improving education and engagement, strengthening institutional oversight, and establishing more participatory governance. The wetland is at risk of vanishing within 50 years due to climate change exacerbating various threats if no action is taken.

1. ENVIRONMENT PROBLEMS AND
MANAGEMENT ASPECTS OF
VEMBANAD KOL WETLAND
Anjana Prasad

2. INTRODUCTION
• Wetlands are areas of marsh, fen, peatland
or water, whether natural or artificial,
permanent or temporary, with water that is
static or flowing, fresh, brackish or salt,
including areas of marine water the depth at
which at low tide does not exceed 6 meters.
(Ramsar Convention)
• Vembanad is one of the largest wetland
systems, comprising lake, paddy fields,
marshes, canals, palm grooves, possess all
attributes of wetlands – mangroves,
waterfowl habitat and fish diversity.

3. • Vembanad Kol wetland is the largest brackish
humid tropical wetland ecosystem in Kerala.
• The wetland system includes the Vembanad
backwater, the deltaic lower reaches of the
rivers draining into it and the adjoining Kol
lands, the fertile low lying fields, lying 0.5 – 1 m
below MSL.
• It is bordered by Alappuzha, Kottayam and
Ernakulam districts of Kerala covering an area
of 16,200 km2 with 10 rivers draining into it.

5. Table 1: Rivers draining into Vembanad Kol
Wetland system

6. PHYSICAL CHARACTERISTICS
• Situated in the humid tropics, this positive
estuarine system with semidiurnal tidal cycle
experiences fairly uniform temperature ranging
from 210C – 360C.
• Rainfall is received during 2 distinct rainy
seasons – southwest and northeast monsoons.
• The average annual rainfall in the area is 3200
mm and salinity ranges from 10 – 22 ppt at
surface during premonsoon.

7. Table 2: Physical characteristics of Vembanad Kol
Wetland System

8. ECOLOGICAL SIGNIFICANCE
• It is unique in terms of physiography, geology,
climate, hydrology, land use and flora and fauna.
• The rich biodiversity and socioeconomic
importance of Vembanad along with adjacent kol
lands led to the declaration of the estuary as a
Ramsar site, a wetland of international
importance in November 2002.
• It recharges the groundwater to supply well
water for the region.

9. • It supports the third largest waterfowl population
during winter in India.
• Wetland flora consists of mangroves (44 species)
and other aquatic species (180 species).
• It is a congregating area for both resident (112
species) and migratory birds (70 species).
• Fauna includes fishes (58 species), shrimps and
prawns (6 species), molluscs (4 species).

10. Endemic species

13. ECONOMIC POTENTIAL
• The fertile kol lands which constitute about 24% of the
paddy lands of the Kerala.
• Retting of coconut husk in the wetland and production
of coir is a major cottage industry predominant in the
area.
• About 50 tonnes of clam shells are exported daily to
different markets in the state.
• Annual fish landing is estimated to be about 746
tonnes.
• Tourism also generates revenue from house boat
operation.

14. MAJOR INTERVENTIONS
• The earliest one was the dredging of a natural
harbour at Kochi and creation of a new island
for harbouring port facilities.
• Thottapally spill for diverting flood water from
Vembanad into the sea.
• Thanneermukkam barrier constructed across
Vembanad lake for preventing salinity intrusion
during dry seasons.

15. • Several minor spillway cum regulators were
constructed in the Kol wetlands for controlling
flood water and to prevent salinity intrusion.
• Interventions in the river basins of the
wetland system include three completed
irrigation projects and nine hydel projects.

16. PROBLEMS ENCOUNTERED DUE TO
• Physical barriers
• Sand mining
• Tourism
• Industrialisation and urbanisation

17. PHYSICAL BARRIERS
• The construction of the Thanneermukkom
barrage and Thottappally spillway has
changed the physico-chemical conditions of
the estuary.

19. • The Thanneermukkom barrier (1976), between
Thanneermukkom on the west and Vechoor on
the east was constructed to prevent saline
water intrusion into paddy fields during the dry
season, and thus support paddy cultivation.

20. • The closing of the barrier stops the tidal effects,
stops the flow of water to the south of the
barrier, and thus hinders natural flushing out of
contaminants.
• The accumulation of agro-chemical effluents
from the southern farmlands and sewage from
adjacent areas leads to increased levels of
water pollution.
• Within few decades of its construction, the area
south of the bund became a hotspot of vector
and waterborne diseases.

21. • Preventing the entry of saline water to the
paddy fields led to an increase in pests and
weeds, which had to be subsequently
eradicated through the heavy use of pesticides
and weedicides.
• The conflicts between the fishermen and
farmers increased. The population of fishes
and shrimps has suffered due to deteriorating
water quality and therefore their numbers
have decreased.

22. • Another problem is that reduced flow leads to
siltation, thereby reducing the depth of the
water body.
• As a result the water carrying capacity of the
water body is reduced.

23. • Thottapally spillway (1955), was built to divert
floodwaters from the rivers into the sea ,away
from Vembanad estuary.

24. • The regulation was done inorder to facilitate
favourable wetland for paddy cultivation.
• The extra water has to be diverted to sea
whereas the minimum wetness in land has to
be maintained.
• Spillway have to be drenched at onset of every
monsoon so as to prevent flooding.

25. SAND MINING
• River sand and gravel are mined extensively from
the rivers of the Vembanad catchments.
• The rate of sand mining is around forty times
higher than natural replenishment.

26. SL N0 COMPONENTS IMPACTS OF MINING
1 River channel Erosion of river banks; river bank slumping; lowering of river channels;
changes in river bed configuration; undermining of engineering
structures like bridges, water intake structures, side
protection walls, spillways, etc.; loss of placer mineral resources
associated with alluvial sand and gravel
2 Surface water Rise in suspended particulate level, turbidity and other pollutants like
oil, grease, etc., from vehicles used for the removal of sands; ponding
of water and reduction in natural cleansing capacity of river water;
aggravated salt water ingression
3 Ground water Lowering of ground water table in areas adjacent to mining sites;
damage to the fresh water aquifer system in areas close to the river
mouth zones
4 Flora & fauna Dwindling of floral and faunal diversity within river basin; decline in
terrestrial insects whose larval stages are in the shallow water sandy
fluvial systems; habitat damage/loss and changes in breeding and
spawning grounds; reduction in inland fishery resources
5 Culture Damage to culturally significant places; places of annual religious
congregations, etc
6 Coast/near
shore
Lack of replenishment of coastal beaches leading to coastal erosion
and reduction in the supply of nutrient elements from terrestrial
source

27. TOURISM
• According to State Planning Board Report tourism
contributes about 9% of total of the gross
domestic product and thus tourism plays an
important role in the development of Kerala’s
economic growth.

28. • Houseboat tourism is affecting the environment
and ecosystem of the Vembanad.
• Number of houseboats as a part of backwater
tourism is increasing tremendously.
• The pollution from the houseboats is the
sewage from toilets, oil from engines, plastic
wastes and food wastes.
• As a result fish population is declining.

30. • The mangrove swamps are affected because
of the construction of resorts and hotels for
tourism around the Vembanad estuary.
• Mangrove swamps are the breeding site for
many fish species and birds. Due to the
declining of mangrove forest in the region
there is a great decline of many species in the
region.

31. INDUSTRIALISATION AND URBANISATION
• Water pollution from a multitude of sources is
the most important reason deteriorating the
quality of the water system.
• Industrial and agro-chemical residues,
municipal sewages, domestic wastes, coir
retting to open water bodies are the major
sources of pollution.

32. • Water quality deterioration is apparent in high
concentration of nutrients, heavy metal
contamination in the estuary mouth, high
incidence of waterborne diseases and
reduction in fish diversity and fish catch
(KWBS 1989)

34. Table 4: Major pollutants of Vembanad estuary
INORGANIC
•Effluents from nearby factories
•Emissions and oil leakage from the engines of house
boats
•Plastic and other inorganic wastes dumped from house
boats
•Fertilizer and pesticides run off from the paddy fields
•Chemical dyes used in coir industry
•Chemical pollution from upstream tea plantations
through the rivers

35. ORGANIC
•Sewage emptied into the canals from the nearby towns
and habitations
•Sewage and other organic wastes from houseboats
•Invasive (Eichhornia) and other aquatic weeds (water
lillies)

36. Coir Industry
• It is the major industry in Alappuzha.
• Coconut coir retting and associated operations,
though small scale, are extensively distributed along
the coastal stretches and contribute heavily to the
organic pollution load of the open water bodies.
• Large quantities of polyphenols along with hydrogen
sulphide are released from the coconut husks during
the retting process, creating anoxic conditions.

37. • Untreated retting effluents which contain high
concentrations of biodegradable organic matter
along with sulphides, nitrate and phosphates
exert heavy BOD and COD stress on the
surrounding aquatic environment.
• The BOD values of Vembanad during 2008-12
range from 3.49 - 5.9 mg/l (Vincy et al.,2012)
which is beyond the permissible limit for inland
surface water (3 mg/l BOD as per IS:2490-1974).

38. Coir submerged for softening in a channel

39. ILLEGAL CONVERSION
• Illegal conversion and encroachment of water
body is visible in areas where tourism has
developed.
• Thousands of hectares of waterbody has been
converted to land over past 150 years.
• According to one study (Gopalan et al., 1983),
23000 ha of the Vembanad had reclaimed
between 1834 and 1984, mainly for agriculture
and aquaculture.

40. • The depth has reduced by 40-50% in all zones
and as a result the drainage capacity has been
reduced to 0.6km 3 from 204 km 3 , a decline
of 75% (James et al., 1997).

41. AGRICULTURE
• The main economic activity of this wetland is paddy
cultivation.
• The labour scarcity, inadequate transportation
facilities, high weed growth and high cost of control,
declining soil fertility, non-availability of quality
seeds are the major problems in this sector.
• To increase the productivity, farmers depend on
heavy use of chemical fertilizers and pesticides,
which inturn pollutes the water and environment.

42. • All this factors have made agriculture expensive.
Hence paddy fields are slowly converted to
plantations as well as to other non-farm activities
which has serious implications on water recharge.
• Other impacts include proliferation of invasive
floating weeds in the region.

43. FISHERIES
• The fishery decline in the lake is due to many
stressors like habitat alterations, overexploitation,
pollution, introduction of exotic fishes,
(Padmakumar et al 2001, Krishnakumar et al 2008,
Krishnakumar et al 2011) etc..
• Another factor is the destruction of mangrove and
its associates which is important to fishery as it
provides rich source of food, breeding and nursery
areas and refuge from predation for shrimp,
crustaceans, mollusks and fishes.

44. Overexploitation and unsustainable fishing practices
• It is evident that the unsustainable fishing practices
deployed by the fishers to tackle the scarcity of
resources exacerbated the situation resulting in
abrupt exhaustion of economically viable fishes.
• Usually stake nets and Chinese dip nets are used. A
total of 1,428 dip nets are reported operating in the
estuary, mostly to the north of Thaneermukom
(Florence, 2012). 3862 stake nets are operated in
Vembanad estuary of which nearly 30% have very
fine mesh sizes (less than 8 mm) (Florence, 2012).

46. • Many indigenous communities across the globe
have been using many poisonous plants as ‘fish
poisons’ for fishing.
• Root of bamboo as well as fruits of sapindas
and entire Acasia torta plant are used as
fishpoisons.
• Fish poisons are used in shallow, stagnant and
slow flowing waters.

47. • Mass poisoning kills the fishes and larvae,
around the major river systems as well as lakes
and estuaries.
Exotic fishes
• An invasive alien species is species which
becomes established in natural or seminatural
ecosystems or habitats, is an agent of change,
and threatens native biological diversity
(Williamson 1996; IUCN, 2000; Shine et al.
2000; McNeely et al. 2001).

48. • Williamson (1996) has suggested the ‘‘three tens
rule’’:10% of imported species will be introduced
into new environments; 10% of these will become
established; 10% of these will become invasives.
• The introduction of exotic species is, arguably, a
more significant anthropogenic stressor than
eutrophication or toxic chemicals (Chapman,
1995) and, along with habitat destruction, is the
leading cause of extinctions and resultant
biodiversity decreases worldwide.

49. • A total of 5 exotics are reported from the lake,
which includes 2 transplanted fishes viz; Catla
catla and Labeo rohita and 3 aquarium scapes viz;
Pangassious suchi, Oreochromis mossambicus,
and Pterygoplichthys multiradiatus. Apart from
these two exotics viz; Clarias garipinus and
Trichogaster trichopterus were reported from the
lake in an independent study( Krishnakumar et al
2009, Krishnakumar et al 2011).

50. • Thus the presence of these exotics in Inland
water bodies like Vembanad integrates the
issue as the native fishes in the lake is facing
threats from various sources.

51. CLAM AND LIME SHELL COLLECTION
• There is a great demand from various industries
for the shells.
• This has led to over harvesting by harmful
methods like bottom trawling as well as
harvesting of even baby clams.
• Thus the deposits are getting exhausted and
the habitats are being destroyed.

54. Vembanad lake may vanish in 50
years: study
(http://www.thehindu.com/todays-paper/tp-national/tp-kerala/Vembanad-
lake-may-vanish-in-50-years-study/article15005270.ece)
According to a study conducted by the National
Centre for Earth Science Studies (NCESS) ,
Vembanad, the largest wetland system in the
country, may cease to exist in another 50 years
as climate change aggravates the complex
threats posed by land use changes.

55. MANAGEMENT STRATEGIES
• Educational level
• Institutional level
• Other management strategies

56. PRELIMINARY THOUGHTS ON SOLUTIONS
• Limitations of academic studies leading to
change or thru’ regulatory institutions.
• Need more ‘outreach’ activities
• Trans‐disciplinary understanding by engaging
students to the local context

57. • Large number of students doing analysis of
local environmental/resource use as part of
curriculum
• Thus instilling transparency, accountability by
participation of these ‘student citizens’ in local
level issues
• Continuity through committed teachers of
local academic institutions

58. • This can strengthen NGOs / people’s movements
who are lone voices now
• Possibility of more regulatory powers to
panchayats to ensure proximity and facilitate local
transparency/accountability in environmental
governance.

59. INSTITUTIONAL ARRANGEMENTS
• Institutional requirements for conservation and
sustainable management of the wetland complex
are defined by the ability to ensure integration of
site management within broad scale
environmental management and development
planning (including river basin and coastal zone
management), and enabling participatory
management, particularly ensuring involvement of
local communities whose livelihoods are linked to
ecosystem services and biodiversity of wetlands.

60. The current institutional arrangements for
management of Vembanad-Kol wetlands are
evaluated in terms of three major aspects, i.e
• policy framework (in terms of inclusion of wetland
conservation and wise use objectives in sectoral
policies),
• regulatory regimes (in terms of sufficiency in
addressing drivers and pressures of wetland
degradation) and
• agencies (in terms of inter-agency coordination for
securing wetland conservation and wise use
outcomes).

61. Policy Framework
• Conservation and sustainable management of
wetlands have been referred to in several
state policy documents.
• The State Water Policy (2008) stresses on
ecosystem integrity, river basin planning and
cross sectoral coordination.
• The need for rational use of ecological
resources for nature based tourism is
highlighted in the State Tourism Policy (2012).

62. • Conservation of wetlands and their integration in river
basin and sectoral development planning have been
stressed in the New Environment Policy of 2006.
• In 2010, the state government initiated implementation
of the Kuttanad Package - a set of interventions
recommended by the M.S. Swaminathan Research
Foundation to mitigate agrarian distress in Alappuzha
and Kuttanad Wetland System with a total outlay of Rs.
1,840 crore. While the design of the package includes
references to the issues of pollution and invasive
species which are adversely affecting the ecological
character of the wetland complex, the overall focus
remains on agricultural practices within Kuttanad.

63. • Despite inclusion of Vembanad as a national
priority site under National Wetland
Conservation Programme1 of the Ministry of
Environment and Forests, an integrated
management plan for the site is yet to be
developed and implemented.

64. Regulatory regimes
• At state level, the regulatory regime for wetlands is
set by The Kerala Conservation of Paddy Land and
Wetland Act, 2008 which restricts conversion of
paddy lands and wetlands to alternate uses.
• The mangrove areas, fish breeding grounds and
backwaters of Kerala and backwater islands have
been classified respectively under categories CRZ I
and CRZ V – Areas requiring special considerations
as per the Coastal Regulation Zone Notification,
2011 under the Environment Protection Act 1986.

65. Activities such as setting up of new industries,
manufacture or handling oil storage or disposal of
hazardous substance; setting up and expansion of fish
processing units; land reclamation, bunding or
disturbing the natural course of seawater; discharge
of untreated waste and effluents from industries,
cities or towns and other human settlements;
reclamation for commercial purposes are prohibited.
• Vembanad is recommended to be declared as Critical
Vulnerable Coastal Area (CVCA) in consultation with
local fisher and dependent communities with the
objective of promoting conservation and sustainable
use of coastal resources and habitats.

66. • The Kerala Tourism (Conservation and
Preservation of Areas) Act 2005 passed by
Government of Kerala envisages conservation,
preservation and integrated development of
special tourist zones.
• The Environment (Protection) Act (1986), The
Indian Wildlife Protection Act (1972 and
amended upto 1992), Biological Diversity Act
(2002) are some of the key national legislations
that pertain to protection of biodiversity and
environment of wetlands in the country.

67. • Mangalavanam was declared a Bird Wildlife
Sanctuary in 2004 to protect the important bird
congregation area of 2.7 ha around the lake.
• The Wetland (Conservation and Management)
Rules, 2010 under the Environment
(Protection) Act 1986 sets out the regulatory
framework for wetlands at the national level.
• The rules as mentioned above provide a
sufficient legal basis for conserving Vembanad-
Kol wetlands. However implementation of the
regulatory framework remains a challenge.

68. Agencies
• The Department of Environment and Climate
Change is the nodal agency responsible for
conservation of wetlands.
• The Kerala State Council for Science, Technology
and Environment (KSCSTE) has been entrusted the
task of management planning for wetlands, including
Vembanad-Kol.
• Operation of Thaneermukom Barrage and Thotapally
Spillway is done by the Irrigation Department.

69. • The Kerala Prosperity Council oversees
implementation of Kuttanad Agricultural Package
aims to sustain agriculture within Kuttanad and
Alappuzha districts and alleviate farmer distress.
• The tourism department is entrusted with the
objective of developing backwater tourism within
Vembanad estuary. Panchayati Raj Institutions are
also being recognized as agencies for regulating
tourism under the Kerala Tourism (Conservation
and Preservation of Areas) Act, 2005.

70. • The region in and around Vembanad Lake has
several coir retting societies, fishery societies,
agriculture farmer’s societies and houseboat
owner’s societies. These societies also provide
benefits to their including protected prices and
compensatory allowances for non-employment
periods.
• While the irrigation department physically
operates the barrage, a decision on the closure
dates is through a committee under the District
Collector, Alappuzha with members drawn from
padashekharam committees.

71. • Within the current institutional set up there is
an apparent absence of a coordination
mechanism, and an identified agency to ensure
that sectoral development programmes do not
create adverse impacts of wetland ecosystem
components, processes and services.

72. • Ashoka Trust for Research in Ecology and the
Environment (ATREE), a Bangalore-based non-
governmental organisation has set up
Community Environmental Resource Centre
(CERC, Alappuzha, Kerala), specifically to
address the wetland related conservation and
livelihood issues related to Vembanad
backwaters, pursuing a deliberative democratic
approach.

73. • Kerala Wetland Management Authority
(KWMA) is a non-profit organization to
conserve, restore and sustainably manage
wetlands of the state to maintain and enhance
their biodiversity and ensure sustained
provision of their full range of ecosystem
services to support well-being of dependent
communities.

74. OTHER MANAGEMENT STRATEGIES
• Domestic wastes: It should be categorised as
biodegradable and non-biodegradable wastes.
Biodegradable wastes should be processed by
composting, vermicomposting, anaerobic digestion
and biological processing. Nonbiodegradable
wastes can be managed by adopting landfilling
method to some extend.
• Industrial Wastes: Industrial units discharging their
effluent draining may be directed to adopt waste
treatment measures.

75. • Regulation of coconut husk retting: The areas
worst hit due to retting activity should be
closed for a few years to allow their ecological
restoration. New technologies should be
adopted.
• Management of fishery resources: It can be
achieved through culturing of endangered
species in open waters and establishment of
protected fish sanctuaries, observation of
closed fishing seasons and regulation in the use
of fishing gears.

76. • Control of salinity intrusion: Scientific operation
policy of the barrier has to be implemented.
• Flood control measures: A detailed evaluation of
rainfall, river discharges, flood water extent and
duration should be undertaken and structural
limitations of Thottapally spillway has to be
rectified.
• Tourism: The houseboats must be provided with
separate collection chamber for human excreta,
plastics and solid wastes. The terminals should have
facilities for treatment of such wastes.

77. • Conservation of mangroves: Afforestation of
mangroves can be done in ecologically selected
areas with species like Avicennia officinalis,
Rhizophora mucronata, Kandelia candel and
Exocoecaria agallocha.
• Afforestation: Vast stretches of forests along the
banks have been destroyed for developmental
activities which has resulted in soil erosion and
sedimentation. Since 75% of the area is already
taken for developmental activities the rest is
proposed for afforestation with indigenous species
like Albizzia lebbek, Artocarpus sp., Careya arborea,
Caryota urens, Cassia fistula,Eugenia sp, etc.

78. • Soil and water conservation: The soil and water
conservation measures are proposed to be adopted in
50% of the total catchment area. The allocation for various
soil and water conservation measures has been made as
25% each for pits-trenches and contour bunds, 5% each
for brushwood check dams and loose rock dam, 10% for
centripetal terraces, 15% each for vegetative hedges like
pineapple and fodder grass.
• Monitoring and evaluation: The hydrological
characteristics, water quality parameters and biodiversity
components have to be monitored periodically to study
the status of the lake and the ecosystem.

79. REFERENCES
1. K. N. Remani, P. Jayakumar and T. K. Jalaja.
Environmental Problems and Management Aspects of
Vembanad Kol Wetlands in South West Coast of India.
2. Priyadarsanan Dharma Rajan, Priyadarsanan Dharma
Rajan, et al.Strengthening communities and institutions
for sustainable management of Vembanad backwaters,
Kerala.
3. Report on visit to Vembanad Kol, a wetland included
under National Wetland Conservation and mangement
programme of the Ministry of Environment and Forests –
Planning Commission Government of India.

80. 4. Safoora Beevi K H, V Devadas. Impact of Tourism on
Vembanad lake System in Alappuzha District.
5. K.A. Sreejith. Human impact on kuttanad wetland
ecosystem - An overview
6. NC Narayanan. Agriculture to Tourism and
Deepening Environmental Crisis in Lake Vembanad
7. Krishna Kumar K, Priyadarsanan Dharma Rajan. Fish
and Fisheries in Vembanad Lake Consolidated
report of Vembanad Fish count 2008- 2011.

81. 8. Conservation and Wise use of Vembanad Kol- An
integrated management and planning framework
by Wetland International – South Asia (WISE).
9.SachinPavithran,N.R.Menon,K.C.Sankaranarayanan
An Analysis of Various Coastal Issues In Kerala.
10. K. Kokkal, P. Harinarayanan, K.K. Babu. Wetlands
of Kerala.