CASE STUDY OF DODDAGUBBI LAKE
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CASE STUDY OF DODDAGUBBI LAKE
A Technical Report prepared by the Working Group
Constituted by KSCST
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March 1979
KARNATAKA STATE COUNCIL FOR SCIENCE AND TECHNOLOGY
Indian Institute of Science, Bangalore 560 012
CASE STUDY OF DODDAGUBBI LAKE
A Technical Report prepared by the Working Group
Constituted by KSCST
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March 1979
KARNATAKA STATE COUNCIL FOR SCIENCE AND TECHNOLOGY
Indian Institute of Science, Bangalore 560 012
Members of the Working Group
Shri Zafar Futehally (Convener)
Vice-President
World Wildlife Fund & Member
National Committee on environmental
Planning & Coordination
Dodda Gubbi Post, Via Vidyanagar
Bangalore 562 1 34
Dr. Cecil J. Saldanha
St. Joseph's College
P. B. 5031
Bangalore 560 001
Dr. Kumar D. Ghorpade
Dodda Gubbi Post
Via Vidyanagar
Bangalore 562 1 34
COMMON IT'.' HEALTH CELL
47/1,(First Flu-,J: i Jt. Marks Road
BAWGAlC-.u-CCOOUI
Shri C. A. Viraktamath
Asst. Professor, Entomology
University of Agricultural Sciences
Bangalore 560 024
Shri Abraham Verghese
Shri D. B. Ghorpade
Dr. B. Mallik
Report on ’Case Study of Dodda Gubbi Lake’
OBJECTIVES OF THE PROJECT:
1.
To estimate the total quantity of water impounded in
the lake during earlier years.
2.
To assess the present status of the lake, resulting
from siltation and other bad land-use practice on the
periphery.
3.
To identify,
in general,
the data to be collected for
monotoring the wetlands in Karnataka State.
1 .
INTRODUCTION;
1.1. On Wetlands:
Wetlands have been recognised as playing an
extremely valuable ecological role in collecting
water during the monsoon months, and releasing
it during the summer months.
Also from the point
of view of recreation and preservation of water
fowl, wetlands play a very significant part.
In a report of the National Committee on Environmental
Planning and Co-ordination, it is.said: Till recently
on account of in-adequate knowledge regarding the
importance of wetlands and the role they play in
establishing the ecological balance, they were
generally regarded as ’Waste Lands’.
This attitude
has led to a large scale destruction of wetlands all
O"
r the world.
Low-lying areas such as marshes, and
peat communities, are being drained, filled or irreversibly
altered under the pretext of land reclamation.
This
became a matter of concern for the nature conservationist
because of the threat to the survival of migratory waterfaWL population which depend solely on these habitats.
wetlands are important for their ecological, floristic,
2
faunistic, limnological and hydrological aspects, apart from
their valuable aquatic birds.
One of the most important assets of a tropical country like
India is water.
The availability of water in any area not
only makes it possible for human beings to reside in the locality
but it also enables them to pursue some occupation like agri
culture, horticulture, animal husbandry, poultry keeping,
pisiculture and others.
It is therefore important that every
bit of water that we have in our country be preserved.
There are two principle ways of conserving water.
One is to
ensure that the land is adequately covered with vegetation so
that during the monsoon months the water per colates into the
soil and recharges ground aquifers.
The other method is to
ensure that all the natural depressions which collect water and
which are known as wetlands are preserved in such a manner that
their water holding capacity is not eroded from year to year.
In Europe a major Project known as Project Mar was sponsored
by the International Union for Conservation of Nature with other
associated bodies to save the wetlands of Europe.
Apart from
being essential habitats for waterfowl, and providing exciting
recreation for angling and for boating, it was found that wet
lands are also far more productive than terrestrial regions.
In terms of kilograms or calories, far more can be got from a
water area in the form of fish and other marine life than would
be tiie case if the same area were reclaimed and wheat or cereals
were grown on it.
It is essential therefore that we in India
name a strong effort to preserve our wetlands in such a way
that they provide us with the material and aesthetic benefits
whi'&Hi they are capable
of. It is, of course, not principally for
aesthetic reasons or because wetlands are an attraction for
ornithologists, that we should consider their rehabilitation in
Karnataka, it is really because they play a very important part
in the water regime.
-2. Location and History:
The Wetland
studied here is the Dodda Gubbi Tank, situated
near Dodda Gubbi Village about 0.6 KM west of the STS bus
terminus.
This tank in Bidrahalli Hobli, Hoskote Taluk,
Bangalore District, has been in existence since 1895, and
recorda pertaining to it are available from the year 1920
onwards.
.5. The Problem:
The Dodda Gubbi Lake has got silted up in course of time. Ever
has .been
since its inception in 1895, paddy/the principal crop around
the lake.
As a result of bad land-use practices, there is
continuous soil erosion,
and the depth of the lake has been
reduced very appreciably in the last few decades.
The natural
vegetation ■'round the water areas should consist of trees and
soil-holding grass species.
When these are cut down and re
placed by agricultural crops, siltation takes place, and the
capacity of the tank gets eroded from year to year.
The problem identified is thur.
soil erosion around the lake
and. siltation of the lake as also consequent reduction of the
tank capacity.
with this problem in mind, a working group
was constituted with the following objectives.
1. To collect data on vegetation and suggest remedial measures
for improving the ecological situation.
2. To evolve a methodology for study of wetlands.
IN VE ST I GA T ION 5:
2.1. The irrigated area of the tank is
151 acres, and the water
spread area is 145 acres at full tank level.
bund is about 2500 feet.
The length of the
There is one waste weir on the left
bank which is about 167 feet, and which is of the clear
overfall type. The rpill.-g.-, is about 5 feet, and the free board
about 4 feet.
The length of the channel is about 2.2 KM.
4
According to visual observations at the tank site, the encroach
ment is almost 40 acres.
According to village records the original
depth of the lake was approximately 37 feet in 1887, the present
depth varies greatly from year to year depending on the rainfall
of the South West and North East Monsoons.
The exact extent of
siltation is diffiuult to determine.
The tank is for the greater part extremely shallow.
In Sept.1976
only about a fourth of the area was found to be under water.
”hile
this might be due to the bad monsoon in 1976, the other contribu
tory factors are heavy silting, poor management of the catchment
which is almost denuded, heavy drawings of water for rice culti
vation, etc.
2. Land use: The land use practice followed by the villagers is very
unsatisfactory, and is affecting the tank’s health and ecology
of the area adversely.
Inspite of repeated Government attempts
to persuade the villagers to go in for serai-irrigated crops like
Bajara, Jowar, etc., the main crop grown is paddy,
from this tank is used.
for which water
Agricultural operations are conducted
right up to the edge of the water, without leaving space for the
perennial vegetation.
This has resulted in a great deal of soil
erosion, and pollution through pesticides and insecticides.
The
tank is considerably silted up owing to operations on the banks.
Cattle is freely allowed to graze on the bank and in the vicinity,
preventing the growth of grass and other vegetation which should
control siltation of the tank.
Thus the natural vegetaion which
holds soil is being altered to annual species of grass which are
not very effective as soil binders.
There is very little tree cover left in the catchment.
The
greater part of the water is used for paddy cultivation, and this,
according to agricultural experts,
for paddy, according to then,
is not a desirable situation,
should be grown only in areas where
there is adequate and natural precipitation.
5. Catchment Area: Excluding the tank, the catchment area is 3.91
sqmailes.
vation.
It is sparsely wooded and most of it is under culti
There is extensive tapping of the tank water through
5
a series of wells dug around the periphery of the tank.
The
main drops noted in the catchment area are:
Joe reals
Eleusing coracana Gaa?rt
(Ragi)
Zee naysi.
(Maize)
Sorghum vulgaro pers
(Jola)
Dilichos biflorus Roxb
(Huruli)
CoJanus cajan Mill sp.
(Thogari)
P'ibre
Crotalarin Jauncea L.
(Sanabu)
>il
Brassica Juncea
(Sasive)
Ricfimus communis L.
(Haralu)
^’lowers
Jasminum 2 sp.
(Mallige )
5iilk Ind.
Morus
(Mulberry)
?iulses
?!.4
Flora:
The vegetation of the tank could be divided into 5 zones
a) Peripheral zone with permanent grass cover, only rarely under
water.
The grasses are stunted, close-cropped probably by
over-grazing.
The plants noticed in this zone are:
Croton bonplandianus Baill.
Cynodon dactylon pers.
Eragrostis sp.
Evolvulus alsinoides L.
Glinus lotaides L.
Lindernia a^tipodn (L) Alston.
b) Zone of partial inudation with moist clayey soil.
Despite the moisture the vcgetation^l cover is poor
and scattered.
This may be due to the constant silting.
The plants noticed are:
Alternanthera sessilis (L.DC)
Coldenia procumbens 1.
Cyperus sp.
Desiaodiun trifle rum (L) DC
Grangeq. modernspatana (L)
Heliotropiuu marifolium Retz.
Phy I2
3 nodiflora (L.) Greene
Polygonum plebium R.Br.
c* Zone of shallow water. Here the plant growth is extremely
poor, and the only species notice "dis .jphinachloa colonuu
(L) Link.
2.
. BIRDS:
I _e bird population varies from season to season.
The re si-
6
dent population consists of Pond Herons, Cattle Egrets, Little
Egrets, Redwattled Lapwings, Brahminy Kites, Large pied Wagtails,
wiretailed Swallows, Whitebreasted Kingfisher, Pied Kingfisher
and several others.
During the migratory season from September
to April, there is a large influx of waders including the Common
sandpiper, Green Shank, Little Ringed-Plover, Little Stint, and
several resident birds and for long periods one can see flocks
of Blackwinged Stilts, Whistlihg Teal, Open-billed Storks, and
others.
were it not for human and cattle disturbance on the periphery of
the water a much larger population of birds would probably reside
here for long periods of the year.
.6. Insect Fauna:
An exploratory survey of the insects occuring in and around the
tank was carried out and this provided some preliminary ideas
about the entomofauna of this area.
The area under water was
very small and this was due to poor rainfall
/.
year and due
to usage for irrigating the paddy fields of the village.
The
peripheral areas were inhabited by tiger beetles (Cicindelida)
.d
and on the sparse vegetation consisting of grass and herbs'
Grass hoppers (Accididae), leaf-hoppers (Cicadellidae) and
planthoppers(Delphacidae).
The zone of partial inundation where
the clayey soil was moist and caked due to cracking, yielded a
few ground beetles (Carabidae) earwigs (Dermaptera) and rove
beetles (Staphylinidne) which were by more abundant towards th<
water’s edge which latter/colonised
carbids,
staphylinids,
Octheridae, Saldidae, Epjiydridae and other flies.
One of the
most interesting finds was the large number of dead Mayfly
(Ephemeroptera)numphs lying half-buried in the soil.
These
nyhphs form an important link in the food-chain of an aquatic
ecosystem,
being the prey of many animals including fish.
The
cause for their death was that the heavy withdrawal of water
for irrigation in a short time trapped these insects which could
not move along with the receding water.
A list of the major
1
7
types of insects associated with the tank is given below:
Zone: 1 (Peripheral area): Cicindelidae, Acrididae, Gryllidae,
Dernaptera, Cicadellidae, Delphacidae, Chrysomelidae,
Zenn: 2 (Partial inundation): Ephemeropeera, Tridactylidae,
Octheridae, Saldidae, Carabidae, Staphylinidae, Cloridae,<2
other unidentified
insects.
.Agricultural operations are conducted right up to the edge of the
rf'ater, without leaving space for the perennial vegetation.
• 7 i-ioni Goring of Wetlands:
At the tiue of the study,
no
it was found that there was/single
person within the administration who was responsible for
looking after these areas.
.'8.Pertinent findings by other agencies:
■
Dr.A.R.Zafar of Osuania University, Hyderabad has done consi
derable work in the nizar:agar and Hussainsagar Dakes.
His
methodology could be used for monitoring the lakes of
Karnataka.
It was found that in a natural lake, there is a
sequential connection between calcium, magnesium,
Potasiun.
The position is :
Ca >M§ > Na > K.
sodium and
However, where
the water is polluted,thi^ changes to something like:
Na > Mg y K.
Ca >
When the water gets further polluted the position
is as follows:
Na > Ca > Mg
K.
Kecommendations:
(Suggested measures for improvement)
a) Restoring the original areas of the catchment by strictly
prohibing agricultural operations in the vicinity of the lake.
o) The crop pattern follo’/ed in the vicinity should be changed;
no crop which needs full irrigation should be allowed, e.g.
paddy would be grown only in areas where the rainfall is
adequate.
Irrigation such as provided by the Dodda Gubbi
8
Wetlands could very well be used for other crops, and in conse
quence the total food output would be much higher.
c) The littoral area of the tank should be planted with perennial
vegetation in order to prevent siltation.
d) Embankments of the tank should be strengthened and the
holding capacity increased.
e) De silting of the tank should be undertaken.
If transportation
of the fertile soil is too expensive, this valuable material
should, be disposed off usefully in neighbouring agricultural
lands.
f) Grazing in the catchment area should be limited and adequate
grazing fees imposed.
g) Irrational use of water from the tank should be restricted,
so that the water level would not fall abruptly.
h) Awareness in the village folk regarding harmful ecological
impact of bad land use practice should be created.
It is very
essential that they oe persuaded to cooperate.
i) Such wetlands should be placed squarely in the charge of a
particular officer in the Department.
(Miner Irrigation and
Public Health) who should establish a procedure for monitoring
the results of the steps taken.
METHODOLOGY FOR STUDY OF 1 .ETL-eNDS;
This essentially involves collection of all relevant data on
Wetlands so as to generate information on the specific problems
of each wetland, usage of wetlands,
flora and fauna, agricul
tural practices in the vicinity, and so forth.
Data and infor
mation to be collected would be on the following lines:
a) --1- as
.. ....si, extent of 6 tch..mnt ..y ■?, -sic.
a) Particulars, like the past history of the lake, the total
amount of water which was impounded initially, and the present
situation.
This would indicate the amount of siltation that
has taken place. A map should be drawn of the catchment area,
and information goton present land use in the catchment area.
c) To find out if the agricultural operations surrounding the
lake are autorised or illegal, and what action is necessary to
ensure! that the catchment area is adequately wooded again and
covered with suitable grass species:
ci) To make a list of the vegetation, the fish fauna, the insects
and to monitor the quality of water periodically, particularly
for the inflow of pesticides etc., from neighbouring lands.
3i}ch data should be got by the spot studies supplemented by
discussions with the local panchayat and by data from the records
of the concerned officer in the Department of Minor Irrigation
and Public Health who is in charge of the particular taluk as
also from the records of the Tahsil Office.
The National
Committee on Environmental Planning and Co-ordination has
prepared a list of wetlands of various states of India
(See
nendix
for list of wetlands in Karnataka). One of
tne best methods for testing the health of a lake is to study
the waterfowl in the surroundings.
The source for considerable
data material on this is the International ’-rildfowl Research
Bureau.
5.
SUM1: ARI:
Dodda G-ubbi lake is an example of ecological damage wrought
by improper use of wetlands. The depth of the lake, -which
was 31 feet around 1887 has decreased to 12 feet today. The
catchment area is sparsely wooded and most of it is under
cultivation with extensive’t-'Pping of the tank water through
a series of wells, around the periphery of the tank.
In
addition to the major crop of Paddy, Ragi, Maize, Jola,
Pulses, oilseeds, and mulbery are cultivated. Agricultural
operations in general and paddy cultivation in particular, have
resulted in a great deal of the soil erosion as well as
pollution through pesticides and insecticides.
There is
extensive grazing in the littoral area so that the natural
vegetation which holds the soil is being altered to annual
species of grass which are not effective as soil binders.
Very little tree cover is left in the catchment area.
10
Based on the above findings, the ’'orking Group has recommended
a series of measures for restoration of the tank.
These
measures include restrictions of agricultural operations in
the vicinity of the lake, desilting of the tank, planting up
of the littoral area with perennial vegetation to prevent
soil erosion, and prohibition of grazing in the catchment area.
APPENDIX
ZETLAND TN KARNATAKA
District
Name of Wetland
Nearest Village/Toun
Belgaum
Dhupdal Lake
Dhupdal
Part of Dhupdal Lake
Shiroder, Ko bhogi
Daroji Tank
Tornagal
Bcllary
Siruguppa Taluk Wetland Siruguppa Taluk
T.B.P. Reservoir
Ilospet
Port Tank
Bidar
Manjira Lif Irrigation
Scheme
Kushnoor
Nagora Project
Kadwad
Water spread of
Chulkinava Project
Basavakalyan
Water Storage under
Upper i'iullemari
Project
KhQda
Water spread under
Karanja Project
Bidar
Kattikamp Tank
J amkhandi
Kendur
Badami
Mamadapur
Bi japur
Chikmagalur
Badra Reservoir
Lakka Rally
Chitradurga
Hadati Tank
Davanaguk
Vanivilasa Sagar
Hi riyur
Devikop Tank
Kalghalgi
Sasarwad
Mundargi
Ainapur Tank
Ainapur
Basaveshwar Tank
Mugalimaagaon
Bclage'ra Buggi
Belagera
Bennitori
Kallhipparaga
Bennitori Madu
Hebbel
Bennitori Madu
Go tur
Bidar
Bi j a pur
Dharwar
Gulbarga
0/57//
£ =
COMMUNITY HEALTH CELL
47/1,(First Floor)3t. Marks flood
bangalo<te • ?»'■:>
District
Name of Wetland
Nearest Village/Tov
Galbarga
Bennitori
Thansanhalli
Bennitori
Malkood
Shankar Gokatta
Shankar
Bhima itewar Kollar
Kollar
Baggil Kallgi
Kallgi
Baggi
Ramatirath
Baggi
Rawoor, Maddi Tola
Ohandankhere Tank
Chandan Khera
Chanderaapalli Project
Chanderaanalli
Ghengta Tank
Ghengta
Clickhalla
Halkathi
Deukatunda
Kallgi
Dotikol Tank
Dotikol
Gokatta
Kaddara,gi
Gokatta
Kamknar
Gokatta
Margoi
Gokatta
Mataga
Gokatta
New Hebbal
Gokatta Rawoor
Rawoor
Gokatta Baggi
Rawoor
Hanikere Hallo
Eenikera
Hirehalla
Hakatti
Hosakere Tank
Ladlapar
Haded Halli lank
Haded Halli
Eagan Madu
Kallgi
Hals gad Tank
Halasgad
Kakatta
Magalanagar
Kani Tank
Malagathi
Khani
Kollar
Kogalgere Tank
Ladlapar
Kumbarkathi
Kasrampalli
Kambarkathi Tank
Lingad Halla
Kodla
Madan Keri
Alahalli
Miryan Tank
Miryan
District
Name of Wetland
Nearest Village/Town
Gulbarga
iiidgunda Tank
iiidgunda
Milan Mudu
Kallgi
Mukramba. Tank
Mukramba
Mullan Tali
Diggoor
Muriaju Hulla
Kallgi
liatkal Tank
Ratkal
Rustumpur Tank
Rustumpur
Suhali Gokath
Suhali
Tailk Arankal
Arankal
Tank Rampurhally
Rampurhally
Tank Tarkespui?
Tarkespur
Tumkunta Tank
Chincholi
Upalawat
Alahalli
Nalaatchkat And
Tank Atchkat
Channarayapatna
Sangameswara Temple
Ambigarahalli
Ranganath i t tu
Palahalli
Hassan
Mandya
Mysore
Nil
Raichur
Hirekasankandi Reser
voir
Koppal
Mohd. Nagar
Koppal
Murdi Tank
Murdi
Tawargera
Koppal
Wedgira Basappa Tank
Gunghalli
Anjanapura Tank
Anjanapura &
Suragondana Koppa
Basehall". Tank
Puradal
Shimoga
Humlcur
llambella Feeder
Sira
This list is by no means complete? there are many other
aireas v/hich can be included.
A number of major rivers have
contiguous areas which could be classified as wetlands. Where
t.he soil is rich, these are naturally used for agricultural crops.
B'ut certain rocky areas could bo selected and developed, and these
s uretches of w iter could then be used for many purposes.
3 .3.1979
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