On 3 June, 2022, on the occasion of the former chief minister Dr Karunanidhi’s birthday, the DMK-led Kodaikanal municipality kicked off a series of development projects, including that of Kodaikanal Lake. About Rs 24 crore has been assigned to the development of a new municipality boathouse, getting new boats, fixing the old boats, renovation of parks, refurbishing of the pavement and the planting of 4,000 flowering plants around the lake; which was created by Sir Henry Vere Levinge in 1863 and covers roughly 64 hectares.
D Narayanan, the Commissioner of Kodaikanal municipality, told The Kodai Chronicle in March, ‘Administrative sanction has been given for the lake project. The technical sanction and process has not yet been completed.’ Work will begin once this takes place, he explained.
According to Praba Shamili Jeeva, a young lawyer and the councillor of ward 7, part of this budget will also include investments in improving lake water quality—the specifics of which are not yet ascertained. ‘We invite suggestions and research by the citizens of Kodaikanal to help us decide the best way forward,’ she said.
Jeeva said that the development will start from the Sir Henry Levinge Memorial, and will be undertaken keeping in mind the historical infrastructure of the lake. ‘We believe that Rs 24 crore will be more than sufficient for significant and sustainable improvements to the lake,’ said Jeeva.

In October 2019, AIADMK’s Edappadi K Palaniswami, then Tamil Nadu chief minister, announced a grant of Rs 106 crore to give Kodaikanal Lake a ‘facelift’. Newspapers reported that the fund would be spent on elements such as repainting the boat house and children’s park, relaying the circumferential road, renovating culverts, lining the walkway with flowering plants, adding 15 new boats, and dredging the lake. The last point is arguably the most important need: improving water quality.
According to publicly available information, that budget too seems to be primarily focused on cosmetic improvements to the lake. The Kodai Chronicle spoke to residents, academics, and members of civil society, and reached out to government officials to understand what needs may require immediate attention. Almost all stakeholders voiced concern about water quality. To this end, we got some experts to weigh in and gathered the results of three different water tests for our readers.


Beauty over Quality
This man-made lake’s aesthetic is undoubtedly important as it affects the livelihood of thousands of families that live and work in Kodaikanal; the town is dependent on tourists, many of whom flock to the lake to nibble on roasted corn, to visit Bryant Park, and for walks, cycle rides and general merriment. ‘The lake is the central attraction for tourists. About 30,000-40,000 tourists come into Kodaikanal every weekend; during peak season, the number is much higher. The 110 registered hotels and all their employees are benefitting from the lake,’ said AR Srinath of Hotel Stonycroft, who is also one of the vice presidents of the town’s Hotel Owners Association.


No doubt the beauty of the lake’s surroundings is integral to the local economy. But equally, if not more so, is the quality of the lake water. It has a direct impact on aquatic life (as demonstrated in the studies cited below). This in turn has an indirect impact on other wildlife and the communities that drink the water further downstream, all the way to the plains. Though Kodaikanal town does not depend on the lake for drinking water, which makes it less of a risk for people living in the township, it can lead to less obvious and far reaching impacts on health, and in turn the economy, in the long run.
Dr Sanjay Kumar (name changed on request), a researcher who has been studying the health of the lake, said, ‘The quality of water in the Kodaikanal Lake directly affects the flora and fauna around the lake. It also flows down into the plains and affects other water bodies that irrigate farmlands and forests.’ Potential pollutants in the lake, he said, range from bio-pollutants, agricultural-runoff and heavy metals.
Water quality is a high priority for many Kodaikanal residents (Madhu Ramnath, Down to Earth, 2015). The potential pollutants include residential and agricultural run-offs. A research paper (August 2021) published in the Arabian Journal of Geosciences pointed at the Hindustan Unilever case when it said, ‘The results also suggest that Hg (mercury) in lake sediments represents its polluted nature; it could also be influenced by industrial and human activities in the catchment.’ There are varying opinions and test results around this issue. The Kodaikanal Municipality informed The Kodai Chronicle that fishing has been banned around the lake, but individuals on occasion can still be spotted with hook-and-line on the north shore of the lake, many residents have noted.

What the Science Says
Two studies, from 2002-03 and 2015, by Greenpeace and the National Centre for Compositional Characterisation of Materials, and by the Department of Atomic Energy (DAE) laboratory, reported, ‘Mercury levels of 1.5 mg/kg and 1.99 mg/kg in lichen [have been] collected from the vicinity of Hindustan Unilever’s now-closed mercury thermometer factory in Kodaikanal, India. In addition to this, three water samples were collected, LW1 at Lavange path approximately 100 m. south and 70 m. downhill of the former HUL thermometer factory, and LaW1 and LaW2 at two spots on the Kodai Lake. The level of mercury was less than 0.5 ng/mL (nanograms/millilitre = ppb) (detection limit) in all the samples.’
In 2017, Asif Qureshi, a researcher from IIT-Hyderabad announced the results of a test of the lake water. The press release from the coalition of civil society and academicians said, ‘The US Environmental Protection Agency prescribes a safe level of 30 microgram/kg of mercury in fish. However, four out of eight fish caught from Kodaikanal lake contained between 31.1 and 41.9 micrograms/kg. Fish caught from a pond fed by the Pambar stream, less than five km. from Kumbakarai falls contained far higher levels—between 94 and 165 micrograms/kg.’ This report was intended to support claims by activists that mercury was leaking from the Hindustan Unilever site.
The August 2021 research paper published in the Arabian Journal of Geosciences said, ‘According to the study, 14 samples were taken from different locations in Kodaikanal Lake. The results from the Energy Dispersive X-ray Fluorescence (EDXRF) elemental analysis indicated that the concentration of mercury in the collected samples ranged from 19 to 30 milligrams per kilogram of sediment’.


The study suggests that this could be caused by ‘activities such as discharge of the solid waste from the thermometer factory’.
Volunteers for The Kodai Chronicle, with no scientific training, collected a sample of water from the lake and sent it for testing to a laboratory that employed the IS3025 testing method. The result was ‘Below Detectable Limits of 0.001’. Dr Kumar said that this could be because the test was not sufficient to detect mercury from the 1-litre water sample, and encouraged the team to attempt the IC PMS test that requires a water sample of 25 litres to be able to detect materials at one parts per billion (ppb). Kumar said that mercury concentrations of over 2 ppb open possibilities for mutation genesis, which includes the possibility for the growth of cancerous cells.

Kumar expressed concerns about the volunteer-led sample collection, saying, ‘The data that’s been collected is missing methodology information, especially with regard to acidification of the collection vessel and methods to mitigate the effect of the sedimentation of particles, not to mention the location isn’t specified, nor the time, nor the depth. As a scientist, all I can say at this point is the report published last year shows significant mercury contamination in the sediments at the bottom of the lake, which isn’t consistent with the data from your commercial report.’
He added, ‘Mercury is a tricky thing to find in freshwater. It’s very sticky, it bonds to the walls of collection vessels, and to particles in the water which might settle and be erroneously filtered out. The scary thing is that mercury is an element. It can’t be broken down. So, if it’s in our environment, it’s not going anywhere. This means that even a small amount can continue to damage us and the environment for generations.
‘What we know at this point is what has been published in peer-reviewed journals with a high level of methodological accuracy, most recently last year, when significant mercury contamination was found in the soil sediments at the bottom of Kodai lake. More research is underway, and will be published in the coming months.’
The test confirms a high presence of bio-pollutants, namely Total Coliforms (IS 5401 test) and TBC (IS 5402 test). The remarks on the test state, ‘[For] the above given water sample, the appearance is not clear and it is not within the acceptable limit in microbiological tests, as per drinking water standards.’ According to a number of news reports (including in The Hindu, September 2020), the water quality has deteriorated tremendously, with bio-pollutants facilitating the growth of invasive species, like Salvinia molesta, which is commonly known as giant salvinia.
Perhaps unrelated, but still worth noting, is a Times of India (July 2017) report on the discovery of a new species of freshwater jellyfish in the lake, which could be an indicator of a drastic change in water quality over the recent years.

Potential Remedial Measures
Remedial measures can be broadly divided into preventative and curative. Marshlands or swamplands, for instance, are an example of a preventative system as they act as naturally occurring filters. Minoo Avari, a local writer and member of the Mya Palani Farmers Association (a group of farmers in and around Kodaikanal), said that the natural marshlands have been a part of the lake since it was built over a century ago. Today, Kodaikanal Lake has lost a lot of its swamplands. ‘A few years ago, a person with political influence began building a hotel on a marsh near the lake. A legal objection was filed against him, and he lost the case. But now I believe he is quietly building again, though it is hard to make out from the outside. If true, it is completely illegal. He is supposed to establish a 200m. buffer zone from the lake,’ Avari says.
He goes on to point out that there are already a few other hotels that have also been built on the swamps and marshlands adjacent to the lake. ‘The last big swamp we have and which lies below Sterling Resort, is also gradually being encroached upon,’ he said.

Curative measures include bioremediation methods like bokashi balls and cow-product-based remedies similar to panchakavayam. ‘These help consume the organic materials in the lake that may come from sewage or other sources,’ says Madhusudhan Iyengar, the head of lake rejuvenation at SayTrees.org.
One application of the proposed Rs 106 crore budget is dredging which, some argue, improves water quality. However, Sanjana Acharya, a masters graduate from the Department of Humanities and Social Sciences, IIT-Madras, cautions against using this method for lake rejuvenation work in her thesis ‘Creating Compliant Nature(s): Exploring Power and Politics in the Rejuvenation of Lakes in Bengaluru’.
‘A lot of development work around lakes very often tends to be techno-managerial—like dredging,’ she states. ‘In a natural healthy ecosystem, one shouldn’t have to do this. While dredging creates space for water, when a water channel/body is clogged up, the harmful effects include disrupting aquatic life, as it causes imbalances in the delicate ecological balance of the lake/river/sea bed, and makes water cloudy.’ Scientists that we spoke to point out that dredging the lake bottom may have another negative impact—kicking up heavy metals that may have settled at the lake bottom. This could result in a new wave of challenges that we cannot foresee yet as Kodaikanal grows.
As the lake development project is still in its nascent stages, much can be done before the budget is spent. A serious consideration of more natural preventative and remediation measures—such as preventing encroachment of natural cleansers like marshlands and allowing them to do what they have for centuries—could perhaps be a more efficient start.

Managing the Lake
‘I would really like to suggest improved strategies of managing it rather than new money-oriented projects,’ says former resident Ian Lockwood, a photographer and writer who visits frequently. ‘For example, why not ban vehicular traffic and parking and keep the lake area exclusively for the use of walkers, cyclists and horse riders? Residents could perhaps have a permit. I worry that all these multiple crore projects are just money spinners for contractors and officials. Matheran, near Mumbai, has banned all vehicular movement within its core area, so we know it is possible, albeit a very difficult challenge.’
This is an idea favored by other residents, who have suggested solutions like this and the e-pass system (implemented during lockdowns, over the past two years), in the past.
As Kodaikanal braces itself to swell in population and, eventually, revenue, the lake’s aesthetic deserves its fair share of attention considering its impact on both residents and visitors. The impact of water quality, however, will almost exclusively be felt by local residents, flora, fauna and everything that lives downstream.
This story was reported with inputs from Reena Raghavamoorthy
Probably the most urgent for water quality is a sewer system around the lake. Kodai has NO public sewage treatment plant. It was turned down because of cost, as I wrote in an early Chronicle piece. Lake has 40 pathogens of which majority are now partly or wholly antibiotic resistant.