How a river in Tamil Nadu turned into a sewage canal

A narrow little rivulet splashes down, bouncing from boulder to boulder as it descends the rockface. It pauses to catch its breath in a tiny pool limned by trees, before rushing downhill again, merging with other streams to form a small river called the Noyyal.

For centuries, the river's 170-km course used to take it past the farms, forests and villages of Tamil Nadu, before sinking it into the embrace of the great Cauvery.

In recent decades, this landscape has changed.

Noyyal’s basin – the area drained by the river and its tributaries – has become one of the densest urban landscapes in the state. The cities of Coimbatore and Tirupur, which are located here, are now among India’s leading industrial clusters. The basin has seen an exponential rise in population. Between 1991 and 2011, the number of people living here doubled from 19.5 lakhs to 42 lakhs. With more people settling in the cities, the urban population mushroomed from 9 lakhs to 33 lakhs. Such a large number of people moved to the cities that the rural population actually fell.

Spikes in population, urbanisation and industrial activity bring with them questions of sustainability.

At Kovai Kutralam in Kachimanathi Reserve Forest, one of the starting points of Noyyal’s journey, the water is so clear, you can scoop it up to drink.

What happens as it flows ahead?

This is the first of a two-part series that traces the course of the Noyyal to see how changes in its basin have impacted it, and what this tells us about the way India is treating her rivers.

From Kovai Kutralam to Coimbatore

For the first couple of kilometres, the rivulet is heard more than it is seen – that is how thick the bushes and trees in the Kachimanathi Reserve Forest are. A local activist M Siva guided me through the forest, down a bumpy dirt track, running along the rivulet. There was birdsong and the chittering of squirrels. An elephant had been sighted in the vicinity, we were told on our way in.

At the end of the track, a forest checkpost appeared, beyond which lay a tarred road. It passed through the buffer area of the forest, winding past a village and a cluster of buildings of the forest department, before reaching the parking lot that marked the boundary of the forest. Here, amidst motorcycles, cars and buses, people stood munching on snacks, tossing plastic everywhere.

The forest had fallen away with a disconcerting rapidity. The river entered a human-dominated landscape, flowing east towards Coimbatore, 30 kms away.

The first sign of population-induced change showed up almost immediately: in the groundwater level in the villages.

In Kalimangalam village, P Selvaraj, a distinguished looking farmer in his fifties, said groundwater can now be found only at 1,000 feet. This claim was repeated in village after village. In Alandurai village, a man said that two decades ago, groundwater was available at 200 feet. Ten years ago, it fell to 600 feet, and now it is 1,000 feet.

If the estimates of the villagers are accurate, groundwater levels are sinking at the rate of 40 feet a year.

No wonder in 2004 and 2009, the Central Groundwater Board declared the 100-odd km stretch between Kachimanathi and Tirupur as over-exploited, a term used for an area extracting more water than its annual recharge.

Yet, curiously, bottled water plants are common in the area. The manager at Diet Aqua, which calls itself a leading-brand of packaged water in Tamil Nadu, said his pumps find water at 700 feet but turned defensive when asked further questions. “I do not have to answer your questions,” he said.

In the past, protests and legal action by local activist groups has forced some plants to shutter, but Siva estimated that 30 packaged water units continued to function. About 20 of them, he said, were illegal.

Apart from the units, the area had many pumping shacks. One of them stood near a dry checkdam – a tiny shed made of asbestos sheets with a groundwater pump and photos of deities inside.

Owned by villagers, the shacks are unregistered extractors of water that fill up tankers heading to nearby cities. Selvaraj said the shacks “extract continuously”. This is partly a result of the worsening economics of agriculture, he explained. “A tanker with 12,000 litres fetches its owner Rs 2,500. In contrast, agriculture does not yield an annual profit of even Rs 15,000,” he said.

The result is a groundwater economy that caters to cities and households and not to the fields.

Another change shows up in the river itself: it runs dry within the first 20-kms. This is odd. Rivers gain volume as they move towards the sea. Several tributaries join the Noyyal in its initial course. Why, then, is it dry?

That is partly because the river is losing its tributaries.

Vanitha Mohan is the vice-chairman of Coimbatore-based Pricol, an automotive components manufacturer, and one of the founders of Siruthuli, an initiative by some business families to revive the city’s groundwater. According to her, no more than one or two tributaries of the Noyyal remain undisturbed.

What happened to the rest?

Land grab

Mohan believes several tributaries have been encroached by farmers. Local activists and researchers, however, point at another factor. According to them, this part of Tamil Nadu is seeing a land-grab. A multitude of campuses – colleges, schools, universities and ashrams – have sprung up in recent years. Be it on the road between Kovai Kutralam and Coimbatore, or even deeper inside the villages off the highway.

According to the activists, several of these campuses, owned by the local elite, have encroached revenue (village) and forest land. Some have even, they say, dammed the tributaries flowing through these lands.

Take a stream called Nallathu Odai. A tributary of the Noyyal, it used to run through the land where campuses of Chinmaya International School and Karunya University now stand. Both institutions, they say, have blocked the stream. Similar charges – of blocking tributaries and usurping land – have been made against Isha Yoga Centre run by new-age guru Jaggi Vasudev.

When contacted, however, all three institutions rejected these charges. Shanti Krishnamurthy, the principal of Chinmaya International School, said: “No stream enters our campus. We run on borewells and rainwater harvesting.” D Ramamoorthy, director (trust affairs) at Karunya University, said: “No section of odai (stream) bearing the name Nallathu odai is in Karunya land.” The university, he added, is “not drawing water from anywhere from any odai or pallam or river.”

A spokesperson of Isha Yoga Centre similarly denied any wrongdoing, “All activities of the foundation are well within the framework of law and aspects," he said. “Vested interest who are posing as environmental activists are behind this false campaign.”

The matter is sub-judice.

If its tributaries are blocked, the quantum of water in the river will come down.

But that may not the only reason why the river runs dry. A 2014 report by the Ashoka Trust For Research in Ecology and the Environment, commonly known as Atree, found a correlation between groundwater levels and the amount of water in the river. The researchers ask whether the river is changing from a "gaining" river to a "losing" river. A gaining river draws water from the aquifer and flows for months after the rains. A “losing” river, on the other hand, recharges the aquifer and therefore dries up quickly.

This is another vector along which the Noyyal has changed. It was perennial.

Local traditions vouch for this, said PA Azeez, a senior scientist at the Salim Ali Centre for Ornithology and Natural History on the outskirts of Coimbatore. The nearby town of Perur has an old temple where a festival called Adi Peruku is celebrated. “Obeisance is given to forefathers in flowing waters,” he said. “It takes place every August. But now, any time you go, there is no water.”

An official of the Public Works Department in Coimbatore echoed Azeez. “Earlier, the river had water for six months due to the rain,” he said. “It had water for another three months due to the streams from the hills. And it was dry for three months due to the summer. Now it has water only during the rains.”

Opinion on when the river went from being perennial to monsoonal is divided. According to Mohan and Azeez, the change happened about 30-35 years ago. The PWD official dated it to 100 years ago.

What is more incontrovertible is this: the river can no longer meet the needs of the people living in its basin. Local communities now entirely depend on piped water supplied by the Tamil Nadu Water Supply and Drainage Board to the village panchayat. This water now comes from neighbouring river basins. But the river continues to be the repository of their sewage.

As a result, the width of the Noyyal as it enters Coimbatore remains the same – a metre and a half – as it was at its origin.

The only difference is: it is now mostly sewage.

The river in Coimbatore

The decay in the river occurred at a time Coimbatore needed it the most.

For a long time, the town got its water from an intricate water management system featuring anicuts and tanks fed by the Noyyal. Said to have been built by the Cholas and their successors from 900 AD onwards, the tanks provided the town with a supply of drinking water and irrigation around the year. It also recharged groundwater aquifers.

A 2013 report by EIA Resource and Response Centre used historical records to estimate the storage capacity of eight lakes in and around the town at 380 million cubic feet of water – about 10,760 million litres of water. The actual storage of water was probably higher – water entering these tanks also percolated into Coimbatore's aquifers, and boosted groundwater availability.

In what is a familiar story across India, even as the quantum of water in the Noyyal fell, Coimbatore's tank system slipped into disrepair. The tanks saw encroachment by both the rich and the poor. The EIA Resource report says the storage capacity in the tanks is now down to 5,097 million litres.

That is just the storage capacity. Given the changes in the Noyyal's flow, it is not clear how much water actually reaches Coimbatore, now a burgeoning city with a population of more than two million people.

In fact, like most other cities in India, Coimbatore cannot survive without importing water. In the 1970s, it began sourcing 75 million litres a day from the nearby Siruvani basin. Subsequently, it added another 150 MLD from the Bhavani basin. This adds up to 225 million litres a day.

This is not enough to meet the city’s water needs, explained the PWD official, who spoke on the condition of anonymity. Taking the estimate of two million residents, he said, “If we give 135 litres per person daily, it comes to about 270 million litres a day.”

Given the amount of water it sources from other basins, Coimbatore has a shortfall of at least 45 million litres.

That is a conservative estimate since the town has a floating population of another 500,000 people – migrant labour, mostly. The shortfall runs deeper. Also, not all the two million people get 135 litres of water everyday. As the Atree report says, “The richer households use more than double the amount of water than the lower income households.”

The shortfall is one reason for the groundwater extraction taking place in the upstream parts of the basin. Within the city too, the PWD official said, there are at least one lakh borewells. The result is predictable: the groundwater levels have fallen. Said Azeez, “Twenty years ago, we used to get groundwater at 80 feet in Comibatore. Now, we have to go to 900 feet.”

It's a hard problem to solve. The PWD is trying to source more water from the predominantly agrarian basin of the Bhavani. But diversion from agricultural use to industrial and urban use comes with its own costs. As agricultural production falls, two big industries in this basin – groundwater pumps and garment manufacturing – have both taken a pounding.

Another option is to revive the Noyyal. But, as the PWD official says, the state government's financial condition is precarious. “We will need to raise funds from other agencies to make the river clean again. But even there, we will need a matching state share.”

In the meantime, every so often, the city gets glimpses of a dystopic future. As the Atree report says, “In the summer of 2013, most households interviewed reported receiving water once every seven-10 days.”

Observing Coimbatore’s deteriorating water situation, Mohan and her peers among the city’s business community came together to start Siruthuli. CR Swaminathan, an industrialist and trustee of the initiative, said it had become apparent that the city needed to revive its tank system. Accordingly, Siruthuli is desilting tanks and removing encroachments from the river and its tributaries, he said.

The work, however, is drawing flak. In Azeez’s view, Siruthuli is “trying to revive the lakes by ensuring there is water supply in the river”. This, he said, has taken the form of removing people living by the river and the tanks. This has given rise to a critique of the project that I heard often – that while it removes the smaller people, it is silent on the powerful people who have blocked the tributaries or are extracting groundwater.

Indeed, as the PWD official, when asked why mineral water units were operating in an over-exploited area, said: “Those companies are owned by either local people with connections to politicians or politicians with local connections.”

When asked about this, Siruthuli officials said they cannot challenge processes like groundwater extraction and the land grab on their own. A senior official at Siruthuli who did not want to be identified said, “We want the PWD to do a survey of all the tributaries to see where they are blocked.”

What this means, however, is that the initiative is moving faster on clearing some encroachments than others. The fallout, said Azeez, is that Siruthuli is seen by farmers as an attempt by the rich and powerful to ensure their water supply.

The human hand

The conflicts along the course of the river are diverse – mineral water units vs villagers, the campuses vs local communities, the city vs its surrounding countryside, rich vs poor, basin vs basin. There is also human-elephant conflict.

Seeking food and water, the pachyderms have started entering villages and towns because land-grabbers' walls have also blocked their traditional paths and waterholes.

These conflicts aren’t necessarily an inevitable corollary of rapid growth. There is a certain man-made quality to the mess. It shows in the resource grab and in the state's failure to manage an increasingly scarce resource.

There are the obvious administrative failures. Take the encroachment in the water bodies. As the PWD official said: “Some of these are five storeyed buildings. That is not something that happens overnight.” The contestation over the tributaries also suggested that they had been blocked and land usurped without triggering administrative action.

This administrative failure, however, goes beyond an inability to take punitive action. For the effective management of water, the government needs to know its quantum and availability. However, questions swirl about the quality of government data.

Both the central groundwater board and the state government data suggest “groundwater levels have been rising or constant in recent years”, which is contrary to what people report in the villages and towns, the Atree report points out.

It said, “There are virtually no estimates of groundwater pumping by households, industry and agriculture.” Existing extraction estimates, it added, are “either circular (using past water level changes to estimate extraction and using extraction again to predict future water levels) or not triangulated independently (e.g. comparing groundwater extraction data from electricity board data, farmer surveys and evapotranspiration estimates).”

Scroll emailed questions flagging these contradictions to Tamil Nadu's Municipal Administration and Water Supply Department, and to the State Ground and Surface Water Resources Data Centre, managed by the state PWD department.

There was no response.

The contradiction in data makes the state government's decision to repeal its 2003 groundwater Act all the more troubling. That year, the state passed the Tamil Nadu Groundwater (Development and Management) Act. It was meant to protect the state's groundwater resources, to guard against over-exploitation and ensure planned development and management. But it was never implemented. And then, in 2013, the state passed an ordinance repealing it.

Among other things, the ordinance said: “If the Act in the present form was implemented and groundwater was not allowed to be tapped, it would have led to a public outcry.”

By doing away with a groundwater management framework, the state government is sowing the seeds for a bigger crisis. A senior official in the state PWD in Chennai said: “Under the Act, people living in overexploited or critical areas would have been allowed to tap groundwater for domestic use and farming but private industry would not have been allowed.”

While repealing the 2003 Act, the government promised to draft a better legislation. Three years later, a new Bill is nowhere in sight.

Scroll emailed questions to Tamil Nadu's Environment Secretary asking about the Bill. The questions have remained unanswered.

In the meantime, groundwater extraction continues.

This backdrop of a worsening water crisis and state failure makes it important to visit Tirupur, the next big city along the Noyyal's journey to the Cauvery.

In 1996, the Supreme Court stepped in to clean the Noyyal after repeated complaints by farmers about the dyeing units in Tirupur polluting the river.

Did the judicial activism save the river? The next story has some answers.

This is the first installment of a two-part series looking at the state of Noyyal river in Tamil Nadu and the lessons it holds for the rest of India.