CONTENTS-
Abstract
Introduction
Morphology of the Lake
Need for the Study
Sources of Pollution
Sampling
Analysis
Solution to the Problem
Conclusion
Acknowledgment

Lake ecosystems are an integral part of the Bangalore city. Lakes in Bangalore were mainly created to serve the need for drinking and agriculture. But unplanned urbanisation and industrialisation has lead to the contamination of these water bodies. Varthur lake, situated in south Bangalore has a water-spread area of   2.5 sq. km. The lake water is mainly used for agriculture and supports a wide diversity of flora and fauna. The inflow of sewage and agricultural runoff in addition to the inflow of contaminated water from Bellandur lake has lead to the rapid deterioration of the lake.

To assess the dependency on the lake water by the people in and around the lake, a socio economic survey was undertaken. A questionnaire was prepared to quantify the direct and the indirect benefits of the Varthur lake and a random sampling was carried out in about 100 houses in and around the catchment area. The results revealed that the people are dependent on the lake water for irrigation and washing of the livestock. They also use the aquatic vegetation in the lake as fodder for the cattle. Most of the people responded that they would be interested in lake conservation and management. Hence a sincere and concerted effort must be undertaken to safeguard the lake ecosystem from further contamination.

Bangalore's topology is full of valleys and ridges and lot of lakes. There are no rivers flowing through it. People from all walks of life from different cultures, speaking different languages and from different strata of economy blend into the community here. Whoever visits Bangalore once, will always long to settle down here, because of the weather conditions, the greenery and the hospitality of the Kannadigas attract them.

Bangalore City is the capital of Karnataka with a population of 42 lakh people. It was founded by Magadi Kempe Gowda in 1550's. It has the distinction of being called   “THE GARDEN CITY”. Now it has been christened as “SILICON CITY”.

Bangalore is the fifth largest city in India. Like other major urban centers, it has unique problems in meeting the increasing demand for water. In absence of nearby dependable water source and also limitations on the use of Cauvery water as a source, there is an urgent need to formulate strategies to conserve the available water. It is also necessary to protect and maintain the lakes in and around the city to ensure clean environment and high water table. There is a need for regulating and controlling the use of underground water.

From Bangalore city, about 18 kms towards south is a lush green serene typical countryside village called “VARTHUR” with a population of about 15,000 people. The village attracts many a passer by because of its large lake called the “Varthur Lake” spread over an approximate area of 2.5 sq. km. The road from HAL Airport, which leads to Varthur winds over a tank bund on this magnificent lake, the drive is such an exhilarating experience that you forget that you are in Bangalore. The sunset particularly is very thrilling.

This wonderful gift of nature was once a dwelling for a variety of fish, aquatic plants, nest for a lot of aquatic birds, like the green cranes, white cranes, water hens and blue cranes and it helped in maintaining a balance in the ecosystem.

Today, the same is polluted and is almost becoming a dead lake. It is also polluting the ground water as the lake is contaminated. It is a flourishing nursery and a house for breeding mosquitoes. This has bothered the citizens a lot and the IX standard students of “K.K Education Society's high School at Varthur”, which is located in the village thought to take up a socio-economic survey to assess the dependency of the people on the wetland.

SIZE :- It is approximately 2.5 sq.kms, . which is about 500 acres in area.

DEPTH :-         i) At the tank bund an average depth   of 3 to 4 feet.

                        ii) At the center about 3½ to 4½ feet.

                        iii) Other side 3 to 4 feet.

ACTIVITY :- All around the lake,   agricultural activity is seen. Paddy, Vegetables, Greens and Coconuts are grown.

SOURCE OF WAT ER:-

•  Rain water in the catchment area of 1.8 sq.kms.

•  Overflow of water from Bellandur lake.

•  Storm water drains of Bangalore City.

DISCHARGE :-    When the lake overflows, water discharges into south Pennar river which flows down further into Tamil Nadu and upto Krishnagiri. All along its path it irrigates the   agricultural fields.

Very foul odour   emanates from the lake. The smell intensifies during summer. The lake is infested with    water hyacinth and other weeds. The colour of water is greenish. Hydrophyte growth is also visible   in many places. The main source of pollution to the lake is discharge of sewage from the Bangalore City.

Lakes have an important role in the recharge of ground water. Lakes are vital parts of fresh water eco-system of any country. Lakes surrounded   by trees and parks perhaps could be the only place where the urban population can find a place close to nature and they provide aesthetic   and recreational potential.

Varthur lake water is used for irrigation. Plants do grow well, but the colour of the leaf have changed to yellow (chlorophyll has changed into leucophyll. (chlorosis)). The farmers grow carrot, beetroot, radish, green leafy vegetables etc.

Our seniors had taken up a project in 1999-2000 and have analysed the water quality of this lake and presented a paper in Lake 2000.   A lot of farmers in and around Varthur and   along the lake totally depend   on this lake for their irrigation needs. They grow paddy which is a subsistence crop serving as a staple food for the whole year.

The polluted water has decreased the yield level, which is a cause for concern, hence to assess the dependency on the Varthur lake, a socio-economic survey was taken up.

Varthur lake is fed by the discharge from the Bellandur lake. Two storm water drains   feed the   Bellandur lake - one coming from Koramangala and Challagatta and other from Fraser town. These   storm water drains carry water from Fraser town, Ulsoor lake, Indiranagar, Domlur and drain into Bellandur lake on one side. The water from BTM layout, Madivala, Austin town, Koramangala, Agara drain into Bellandur lake from the other side.   The water that flows through the   storm water drains is full of   fecal matter and sewage. The sewage gets mixed up with   storm water   due to the following reasons.

The sewage lines run parallel to the storm water drains. The service line and space provided has been occupied unauthorisedly and houses constructed in this space hampers maintenance work.

The sewage pipes have broken midway and are continuously discharging sewage into the storm water drains.

Rise in population has led to the rise in revenue plots and illegal layouts have sprung up. These layouts do not have any proper lines for disposal of sewage. Instead sewage lines are directly connected to the storm water drains.

  Many houses along the storm water drains dispose the solid waste and   night soil directly into the storm water drains.   The BWSSB's sewage treatment plants capacity is low by atleast 25% , hence the sewage is discharged untreated.   Effluents flowing out of factories NAL, HAL,   nearby foundries and garment factories also contribute to the pollution. To a large extent rotten vegetables, dead chicken, chicken feathers and waste is also directly dumped into the lake.

About 100 farmers who are dependent on this lake water for irrigation were interviewed using a standard questionnaire.

The questions posed during the interviews were classified under the following headings:

The use of ground water resources was included in the survey to identify trends in the overall reliance on lake resources compared to ground water.   Questions regarding ground water recharge were intended to detect   changes in the local water table that could be the result of reliance on bore wells.

            Questions were asked about wild fish populations pertaining to qualitative information about changes in the ecology of the lake, especially the biodiversity and abundance of wildlife. These topics, along with questions regarding aesthetic value, sought information on less tangible benefits provided by the lake that may be affected by a decline   in its overall condition. Potential harm to the local population as a result of this deterioration was also investigated through questions regarding mosquito populations and incidents of insect and water-borne diseases.

The heritage value of the lake as well as family commitment to remain in the area were investigated through questions regarding both family history and their desire to see future generations remain near Varthur. Determining residents overall concern for the future of the lake was the motivation behind the question regarding support for future reclamation   efforts.

All respondents used bore wells to meet their domestic water needs. Most    of the households interviewed purify their drinking water with a filtration system, and one household boiled the water prior to drinking.             83% of the survey population, relied exclusively on lake water to irrigate their crops, and 2 more used both   the lake and bore wells for this purpose. 10 of the houses that use the lake for irrigation reported a decline in both   the quality and quantity of crops due to pollution of the lake water.

14 households raise cattle, primarily for milk. At least 11 of these farms rely exclusively on plants growing in and around Varthur lake to feed their cattle. 9 of these 11 farms rely on the sale of dairy products for part of their income; the percentage of total income derived from dairy products for these farms ranged from 1 to 74%, with mean and medium averages of 32% and 40%, respectively.

None of the households were involved in fishing, however, one was actively engaged in aquaculture. 86% of the respondents indicated that they had noticed deterioration in the quality of the lake. Although estimates of when this deterioration began varied widely, over half of the estimates ranged from 15 to 20 years ago. 10 of the farms reported a reduction in the quality and quantity of their crops as a consequence of polluted lake water. 18 of the respondents indicated that the mosquito population around Varthur has increased in recent years. One respondent indicated that family members had suffered from Malaria and Dermatitis. Another household that did not filter or boil their drinking water reported problems of viral fever. The smell given off by the lake in winter months was considered to be a nuisance by 16 households.

Atleast 60% of the families had lived in the area for over 100 years. Most of the households surveyed would actively support reclamation effects for Varthur lake. Most of the surveyed households visit the lake on an annual basis to submerge idols of the Hindu deity, Lord Ganesha, as part of a religious ritual.

The lakes over the years have played a key role in maintaining a salubrious climate for which Bangalore is famous. This lake needs to be protected for a healthy co-existence and to maintain ecological balance. Nevertheless this lake   could become an agent for ecological crisis and a threat to public health. Hence the following measures are suggested.

SHORT-TERM MEASURES:

•  Avoiding the flow of sewage into the storm water drains by educating the people about sanitation.

•  Providing “additional traps” along the upper reaches of the drains.

•  Providing bar screens at the mouth of the lake for the drains.

•  De-weeding of the lake.

•  The drinking water should to be treated with chlorine [Chlorination] to avoid contamination and purify the water.

•  Bring public awareness-educate the people to boil the water before they drink.

•  Rearing special kind of fish, which feed on the dirt in the lake.

•  Introducing gambusia fish into the lake to feed on mosquito larvae.

•  Banning or earmarking   a specific area for the immersion of Ganesha idol during the Ganesha festival.

•  Creating public awareness to keep the lake clean by sign boards.

•  Formation of a lake protection committee by involving the local people.

•  Educate people not to wash greens and vegetables in the lake water.

  LONG-TERM MEASURES:

•  Clearing of the houses unauthorisedly built on the service lines so that the sewage lines can be maintained.

•  Construction of the toilets[Sulabh Souchalya] to avoid mixing of sewage with sullage in the storm water drains.

•  Strict punishment to the public if they   encroach the lake            Set up two   sewage treatment plants on a smaller scale at the point where the storm water drains feed   the lake.

•  Pass legislation to strictly monitor the growth of revenue layouts, which are formed unauthorisedly.

•  Regular monitoring of the lake water by the State pollution control board.

•  The village panchayat should install a chlorination plant to treat the drinking water.

•  Formation of standing committee, comprising environmentalists, Bangalore city corporation members, sewage board officials, Village Panchayat members etc.

Our motto is to conserve Mother Nature so that life can sustain and the balance be maintained. The principle adopted is

“LIVE AND LET LIVE”

“CONSERVE LAKES-BE PROSPEROUS”

•  Man has the right to live but not to destroy. Mother Nature is dying, save her.

•  Let us resolve to enhance the life span of lakes.

•  Let us have constructive approach towards these lovely wealth of nature.

•  Save lakes for prosperous and healthy life.

•  We are fouling our own nest. If the lake is not saved, it will age and die a premature death and it may become “ENDANGERED”.

FOLLOW-UP:

•  The Bangalore Water supply and the sewage Board have submitted a report for cleaning the lake to the state government and is awaiting the approval.

•  Further, the village panchayat   has to treat the drinking water before it is supplied to the houses on the first priority.

•  Student committees should be set up to educate the villagers about the hazards the lake.

•  The school should adopt different areas of the village to propagate the correct measures of health and hygiene.

•  To keep a strict vigil on farmers so that they do not wash greens and vegetables in the lake water.

•  The school can organize public awareness programs by inviting NGO's to help in the conservation of the lake.

We are thankful to .Dr.T.V.Ramachandra and Miss Ahalya   from IISc. Mr.M.A.Khan,   Mr. M.K.Khan, Mrs. Alli Rani, Mrs.Noor Fathima, and   Mr. Masood Ahmed     from Varthur High School and Mr. M.Z.Khan,    Lecturer Environmental –Science,Government PU College,KGF   -   for helping and guiding us to complete this project successfully.

K.K English High School,
Varthur, Bangalore – 560 087,
Karnataka. India.
Phone: (080) – 8538051