Garbage dumped in the Cauvery at Kooduthurai, Tamil Nadu.  

Pollution in rivers has emerged as a major concern all over the world. This is especially true for a developing country like India, where pollution levels of all the major rivers have reached alarming proportions. Of the 445 rivers monitored by the Central Pollution Control Board, as many as 275 are polluted, a number that has risen steeply from 121 in five years, the premier pollution-monitoring agency found in a survey.

The board also found that as many as 150 stretches of India’s rivers have a biological oxygen demand — a key measure of water quality — of over 3 mg per litre. In fact, it was 10 times more than the safe limit on 35 stretches. If this situation continues, the demand of freshwater for drinking, irrigation and industrial use would soon be unmanageable. The rivers have suffered badly in recent years because large quantities of municipal and industrial waste are being dumped into them every day.

The administration led by Prime Minister Narendra Modi, like the other regimes that preceded it, has been careful in expressing concern about river pollution since it’s an emotive issue with many Indians. However, the concern is mainly restricted to the Ganga, the cleaning of which has been declared a key policy goal. Despite pious intentions and after years of effort and billions in funding, precious little has been achieved. The Ganga and its tributaries, particularly the Yamuna that flows past Delhi, remain critically polluted.

Many more polluted

The single-minded focus on the Ganga blurs another reality, that there are many other rivers that are critically polluted. The rapid urbanisation and industrialisation in southern India have, for instance, dirtied the major rivers in the peninsula, which as elsewhere has been compounded by administrative and public apathy.

The plight of the Cauvery is a case in point. The 765 km-long lifeline of Karnataka and Tamil Nadu gets national attention only when conflicts break out every year like clockwork regularity over the sharing of its water between the two states. The rest of the time nobody has any compunction about releasing untreated effluents into it.

Highly toxic

The Cauvery carries extremely high concentrations of toxic chemicals, according to an Anna University study released in December. Although its annual discharge into the Bay of Bengal is relatively low at 8.3 cubic km, the amount of total dissolved solids is more than 750 mg per litre, which is about five times of the load in the Ganga, the study said. The situation is so bad that not only has much of the waterway turned toxic but the groundwater in parts of Tamil Nadu and Karnataka has become contaminated by ions of sodium and chlorine, particularly near industrial areas, confluence of tributaries and near the coast. High levels of sodium ions in water cause hypertension and reproductive toxicity.

The high levels of pollution, mainly due to indiscriminate discharge of effluents from textile, dyeing, cement and chemical industries located along the river’s course, is rapidly making its water unsuitable even for drinking. The Cauvery, it is becoming increasingly clear, is dying. So all that political posturing and fighting over the sharing of its water between Karnataka and Tamil Nadu when it can’t be used for any practical purpose is nothing but a pathetic attempt to score brownie points.

If we are to save the river that’s so vital to grow food and meet the drinking needs of many cities, it’s absolutely necessary to ensure that it flows cleanly again. This can only be achieved if all the municipalities that discharge sewage in the waterway start investing in treatment plants, and state authorities institute stringent rules to install effluent treatment plants in the industrial areas along its course. There is also a need to rejuvenate the vanishing forest cover in its headwaters in Kodagu.

Back from the dead

There are many examples of river clean-ups that we can draw upon to do this. The most prominent among them is that of River Thames in England. The Thames was so polluted that it was declared biologically dead in 1957, when it was reduced to a foul-smelling drain.

After sustained public outcry in the 1970s, there was coordinated action by the authorities to ensure that the urban and industrial waste flowing into the river was processed through treatment plants. Reduced use of chemical fertilizer and pesticides in agriculture and tighter regulations on toxic industrial waste were brought in.

But most importantly, the involvement of local communities was vital in achieving this remarkable environmental feat. By the 1980s, the river was clean again.

There is no reason that this cannot be done for the Cauvery as well. There are some signs that the tide might be turning. Bengaluru, the major city on its course, has taken steps to stop the indiscriminate dumping of sewage into the river by investing in treatment plants and enforcing stringent rules. But stricter action is required to deal with industrial waste disposal into the river across both states.

The Cauvery must be saved and the best way to go about it is to raise awareness so that public opinion forces the authorities to act. The river can still be saved but the push must come from the people. If the river is worth fighting over, surely it’s worth cleaning up.

Soumya Sarkar is Managing Editor of IndiaClimateDialogue.net. @scurve

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