The Ganges River begins in the Himalayas, roughly three hundred miles north of Delhi and five miles south of India’s border with Tibet, where it emerges from an ice cave called Gaumukh (the Cow’s Mouth) and is known as the Bhagirathi. Eleven miles downstream, gray-blue with glacial silt, it reaches the small temple town of Gangotri. Pilgrims cluster on the rocky riverbank. Some swallow mouthfuls of the icy water, which they call amrit—nectar. Women in bright saris wade out into the water, filling small plastic flasks to take home. Indians living abroad can buy a bottle of it on Amazon or on eBay for $9.99.

To hundreds of millions of Hindus, in India and around the world, the Ganges is not just a river but also a goddess, Ganga, who was brought down to Earth from her home in the Milky Way by Lord Shiva, flowing through his dreadlocks to break the force of her fall. The sixteenth-century Mogul emperor Akbar called it “the water of immortality,” and insisted on serving it at court. In 1615, Nicholas Withington, one of the earliest English travellers in India, wrote that water from the Ganges “will never stinke, though kepte never so longe, neyther will anye wormes or vermine breede therein.” The myth persists that the river has a self-purifying quality—sometimes ascribed to sulfur springs, or to high levels of natural radioactivity in the Himalayan headwaters, or to the presence of bacteriophages, viruses that can destroy bacteria.

Below Gangotri, the river’s path is one of increasing degradation. Its banks are disfigured by small hydropower stations, some half built, and by diversion tunnels, blasted out of solid rock, that leave miles of the riverbed dry. The towering hydroelectric dam at Tehri, which began operating in 2006, releases a flood or a dribble or nothing at all, depending on the vagaries of the season and the fluctuating demands of the power grid. The first significant human pollution begins at Uttarkashi, seventy miles or so from the source of the river. Like most Indian municipalities, Uttarkashi—a grimy cement-and-cinder-block town of eighteen thousand—has no proper means of disposing of garbage. Instead, the waste is taken to an open dump site, where, after a heavy rain, it washes into the river.

A hundred and twenty miles to the south, at the ancient pilgrimage city of Haridwar, the Ganges enters the plains. This is the starting point for hundreds of miles of irrigation canals built by the British, beginning in the eighteen-forties, after a major famine. What’s left of the river is ill-equipped to cope with the pollution and inefficient use of water for irrigation farther downstream. Below its confluence with the Yamuna River, which is nearly devoid of life after passing through Delhi, the Ganges picks up the effluent from sugar refineries, distilleries, pulp and paper mills, and tanneries, as well as the contaminated agricultural runoff from the great Gangetic Plain, the rice bowl of North India, on which half a billion people depend for their survival.

By the time the river reaches the Bay of Bengal, more than fifteen hundred miles from its source, it has passed through Allahabad, Varanasi, Patna, Kolkata, a hundred smaller towns and cities, and thousands of riverside villages—all lacking sanitation. The Ganges absorbs more than a billion gallons of waste each day, three-quarters of it raw sewage and domestic waste and the rest industrial effluent, and is one of the ten most polluted rivers in the world.

Indian governments have been trying to clean up the Ganges for thirty years. Official estimates of the amount spent on this effort vary widely, from six hundred million dollars to as much as three billion dollars; every attempt has been undone by corruption and apathy. Prime Minister Narendra Modi, elected in May of 2014, is the latest to try. Modi and his Hindu-nationalist Bharatiya Janata Party, or B.J.P., campaigned on promises of transforming India into a prosperous, vibrant modern society, a nation of bullet trains, solar farms, “smart cities,” and transparent government. Central to Modi’s vision is the Clean India Mission—Swachh Bharat Abhiyan. He insists that rapid economic development and raising millions of people out of poverty need not come at the cost of dead rivers and polluted air. So far, however, the most striking feature of his energy policy has been the rapid acceleration of coal mining and of coal-fired power plants. In many cities, the air quality is hazardous, causing half a million premature deaths each year.

Two months after Modi was elected, he announced his most ambitious cleanup initiative: Namami Gange, or Obeisance to the Ganges. As evidence of his capability, Modi points to the western state of Gujarat, where he served as Chief Minister from 2001 to 2014, presiding over impressive economic growth. The Sabarmati River, which flows through Ahmedabad, the largest city in Gujarat, was given an elegant tree-shaded esplanade, where residents now walk their dogs and take the evening air; still, it remains one of the most polluted rivers in India.

Modi is better known for his long association with the radical fringe of Hindu nationalism than for good-government initiatives. Born into a low-caste family (his father sold tea at a railway station), he was just eight years old when he began attending meetings of the Rashtriya Swayamsevak Sangh, the mass organization that is the most aggressive face of Hindu-nationalist ideology. In his twenties, he became a leader of the R.S.S.’s student affiliate, and soon after he befriended another leading activist, Amit Shah, who became his most trusted aide in Gujarat.

In 1990, Modi, already recognized as a future leader of the B.J.P., was one of the main organizers of a protest pilgrimage from Gujarat to the town of Ayodhya, in the northern state of Uttar Pradesh. According to legend, Ayodhya was the home of the god Rama, and the protesters demanded that a Hindu temple be erected on a site occupied by a sixteenth-century mosque. In 1992, Hindu mobs converged on Ayodhya. They tore down the mosque, prompting nationwide riots, in which two thousand people died. Ten years later, when Modi was Chief Minister of Gujarat, Hindu pilgrims made another visit to Ayodhya. As they were returning, Muslim mobs set their train on fire and fifty-nine people were burned alive. In reprisal, more than a thousand Muslims were killed, while the police stood by. Modi was widely accused of indifference, even of complicity, and, although he was later exonerated by the Supreme Court, he was denied a U.S. visa for a decade.

In 2014, Modi won a landslide election victory. Voters were tired of corruption, and Modi, a charismatic orator and an astute user of social media, promised to eradicate it. The business community clamored for deregulation. Young Indians were desperate for jobs. The Nehru-Gandhi dynasty had exhausted its political appeal, and its choice for prime minister, Rahul Gandhi, the grandson of Indira, was a feeble campaigner, no match for Modi’s dynamism.

For the most part, Modi did not need to appeal to Hindu-nationalist passions. But his promise to clean up the Ganges plays directly into India’s charged religious and caste politics. Two problems are paramount. One is pollution from the tannery industry, which is centered in Kanpur, roughly midway along the river, and is almost entirely Muslim-owned. The other is sewage from Varanasi, two hundred miles downstream—an ancient city, considered the spiritual center of Hinduism, where the river is effectively an open sewer. Both cities are in the state of Uttar Pradesh, which has a population of two hundred and fifteen million and is central to Indian electoral politics. It is also notorious for extreme poverty, rampant corruption, rigid caste divisions, and communal violence, in which most of the victims are Muslims. At least half the mass killings recorded in India in the past quarter century have occurred in Uttar Pradesh.

In 2014, when Modi’s ministers began to discuss the Namami Gange project, the details were vague and contradictory. Naturally, the sewers of Varanasi and the tanneries of Kanpur would receive special attention. The Ganges would become a “hub of spiritual tourism,” but there was also talk of building dams every sixty miles along the busiest stretch of the river, to facilitate the transport of heavy goods. Four battalions of soldiers would be organized into the Ganga Eco-Task Force. Local communities would join the effort.

Modi has spoken of being inspired by the transformations of the Chicago River and of the Thames, but they are barely a tenth the length of the Ganges. Restoring the Rhine, which is half the length, took almost three decades and cost forty-five billion dollars. The budget for Namami Gange is about three billion dollars over five years.

Modi announced the effort in Varanasi. Like the Ganges, Varanasi (formerly Benares) is said to be immune to degradation, although this is hard to reconcile with the physical reality of the place. The city’s labyrinthine alleys are crowded with beggars, widows, and ragged ascetics, corpse bearers and the terminally ill, cows, dogs, monkeys, and motorbikes. A mixture of ornate temples and smoke-shrouded cremation grounds, Varanasi swarms with foreigners drawn by the promise of seeing India at its most exotic—dreadlocked hippies, Israeli kids just released from military service, Japanese tour groups in white surgical masks, stolid American retirees. When I visited, last October, the garbage and the post-monsoon silt lay thick on the ghats, the four-mile stretch of steps and platforms where thousands of pilgrims come each day to take their “holy dip.” The low water at the river’s edge was a clotted soup of dead flowers, plastic bags, feces, and human ashes.

Cylindrical towers, one emblazoned with an image of Shiva, stood at intervals along the riverfront—sewage-pumping stations that are designed to protect the most sensitive expanse of the bathing ghats, from Assi Ghat, in the south, to Raj Ghat, in the north. R. K. Dwivedi, a stout, sixty-four-year-old man who was in charge of the treatment plants, told me that the pumping stations, which were built in the nineteen-seventies, had recently been upgraded. But less than a third of the sewage that is generated by the 1.5 million people of Varanasi is treated; the rest goes directly into the river.

“From Assi Ghat to Raj Ghat, you will find almost nil flow coming to Ganga,” Dwivedi said. I pointed out that the Assi River, a thirty-foot-wide drainage channel that flows into the Ganges just upstream of Assi Ghat, bypasses the pumping stations and pours raw sewage into the river. Dwivedi said that there was a comprehensive plan to install a sewerage system in the newer, northern half of Varanasi. But the engineers were still struggling with the challenge of laying sewer lines under the tortuous lanes of the old city—a problem that defied the efforts of Dwivedi’s predecessors all the way back to the days of the Raj.

The first concerted attempt to clean the Ganges began in 1986, when Prime Minister Rajiv Gandhi launched the initial phase of what he called the Ganga Action Plan. He made the announcement on the ghats of Varanasi and focussed on the city’s sewers and the tanneries of Kanpur. The effort was haphazard. Thirty-five sewage-treatment plants were built in the three most populous states along the river—Uttar Pradesh, Bihar, and West Bengal—but their capacity was based on the population at the time, and they quickly became obsolete. Moreover, although the central government paid for the plants, municipalities were left to operate them, and often failed to pay the wages or the electricity bills to keep them running.

In 1993, under Prime Minister P. V. Narasimha Rao, new treatment plants and other pollution-abatement projects were added on several of the river’s larger tributaries. This phase was followed by the creation, in 2009, of the National Ganga River Basin Authority, by the government of Prime Minister Manmohan Singh. For the next two years, the cleanup was directed by Jairam Ramesh, the environment minister. Ramesh, who is now an opposition member of Parliament, is in his early sixties, with a head of thick gray hair. In many respects, he epitomizes the old Congress Party élite that Modi detests: cosmopolitan, fluent in English, Western-educated, with graduate studies at Carnegie Mellon and M.I.T.

Ramesh told me that he had taken a more comprehensive view of the problem than his predecessors. The unfinished hydropower projects I’d seen in the Himalayas were the result of a Supreme Court decision, which he had strongly supported, to halt construction in the ecologically sensitive headwaters of the river. Ramesh also ordered that the next generation of sewage-treatment plants be based on population estimates for 2025. The central government, in addition to funding plant construction, would bear seventy per cent of the operating and management costs for five years. Several new treatment plants will become operative during Modi’s term, and he will likely take credit for them. Ramesh added that the Prime Minister’s vow to “build more toilets than temples” was his own slogan in 2011. “And Modi attacked me for it,” Ramesh said. “He is shameless.”

I asked Ramesh if he saw anything in the Namami Gange plan that was new. Only one thing, he said: the addition of Hindutva, the ideology of “Hindu-ness,” which had cursed India with a poisonous history of communal strife.

As his parliamentary constituency, Modi chose Varanasi. “I feel Ma Ganga”—Mother Ganges—“has called me to Varanasi,” he said in 2014. The idea came from Amit Shah, Modi’s campaign manager in Uttar Pradesh and former aide in Gujarat. Uttar Pradesh epitomizes the impoverished heartland of Hindu nationalism, and Shah was given the job of delivering the state to the B.J.P. He is a brilliant and ruthless strategist, and it was an ugly campaign. Modi attacked Arvind Kejriwal, his opponent in Varanasi, as “an agent of Pakistan”—an incendiary charge.

Shah, who in 2013 had reiterated the call for a Rama temple to be built on the site of the demolished mosque in Ayodhya, made no effort to court Muslim voters. Instead, he concentrated on maximizing turnout among lower-caste Hindus, deploying thousands of young R.S.S. volunteers in an unprecedented door-to-door campaign. In the end, Modi took seventy-one of Uttar Pradesh’s eighty parliamentary seats, enough to give him an absolute majority in the lower house of Parliament. Shah was appointed president of the B.J.P.

After this divisive campaign, it was noteworthy that Modi chose Uma Bharti to head a newly created Ministry of Water Resources, River Development, and Ganga Rejuvenation. Bharti is often referred to as a sadhvi, the female equivalent of a sadhu, or holy man, and has been a controversial figure throughout her career. A fiery Hindu nationalist, she was a prominent leader of the militants who tore down the mosque in Ayodhya in 1992 and still faces six criminal charges in the Uttar Pradesh courts, including for rioting, unlawful assembly, and “statements intended to cause public mischief.” In a separate case, now before the Supreme Court, she is charged with criminal conspiracy. (Such prosecutions of powerful politicians almost never result in a conviction.)

In 2004, Bharti told reporters that the demolition of what she called “the disputed structure” in Ayodhya was “a victory for the Hindu society.” Later, when an official commission of inquiry accused her of inciting the mob violence, she denied calling for the demolition of the mosque but said, “I am not apologetic at all. I am willing to be hanged for my role.” (Neither Modi nor Bharti agreed to requests for an interview.)

The Hindu nationalists I spoke with in Varanasi—public officials, businessmen, priests, veteran R.S.S. activists—dismissed any criticism of Bharti or Modi. One evening, I climbed a steep flight of steps from the ghats to the tiny Atma Veereshwar Temple, where I met Ravindra Sand, a Saraswat Brahmin priest who is deeply engaged in the religious traditions of Varanasi and the river. He told me, “You can call Modi a rightist, a fundamentalist, an extremist, whatever you want.” What really mattered, he said, was the passion and faith Modi was bringing to the monumental challenges facing India. “He is honest like anything. He sleeps three hours a night. I pray to God for Modi to be the P.M. of India for the next decade, at least.”

When I mentioned the destruction of the mosque in Ayodhya and the massacre of Muslims in Gujarat, Sand looked at me as if I were missing the point. “Should I be honest?” he said. “I do not like Muslims at all.” Modi felt the same way, he added. Ayodhya was the home of Lord Rama, and the Muslims had been the initial aggressors in the Gujarat incident. “If a person can slap you once, and I reply to him with four slaps, you are going to blame me for the fighting? It is not correct. I am sorry to say, these Muslims are not at all comfortable anywhere.”

Such views are expressed openly by mainstream B.J.P. supporters in Uttar Pradesh. “Modi is a devotee—he is determined,” Ramgopal Mohley, the mayor of Varanasi, told me. Namami Gange would leave the ghats spotless; garbage would be trucked to a new waste-to-energy plant; discarded flowers from the cremation grounds would be turned into incense. Like Modi, Mohley had travelled to Japan to scout out ideas in Kyoto, which is home to seventeen UNESCO World Heritage Sites. Like Varanasi, he said, “Kyoto is also a city of narrow lanes and temples. Under their lanes, there are subway lines. Over the lanes, there are flyovers.” He conceded that Varanasi had more lanes and more temples—and, of course, India is not Japan.

I asked Mohley what he thought of Uma Bharti’s appointment. “Everyone loves Uma Bharti,” he said. He declined to say whether Muslims might feel differently, steering the conversation back toward Bharti’s plans for the river. “By October of 2016, you will start seeing the cleanness, up to twenty per cent. In another year, by 2017, you will start seeing the real cleaning.

“Umaji,” he added, using the Hindi honorific, “has said that if Ganga is not cleaned in three years’ time she might undertake samadhi.” Samadhi is commonly defined as a state of deep, spiritual concentration, leading to a sense of oneness with the universe. For some ascetics, my translator added, it involved climbing into a ditch and burying oneself alive.

The next state-government elections in Uttar Pradesh will take place in mid-2017. Modi’s national victory gave him control of the lower house of Parliament, but he does not control the upper house, which is largely elected by state legislatures. Uttar Pradesh is currently ruled by the Samajwadi Party, which has heavy Muslim support.

Modi and Amit Shah launched the campaign on June 13th in Allahabad, at the sacred confluence of the Ganges and the Yamuna. The preceding weeks had seen a series of violent skirmishes in the town of Kairana, in western Uttar Pradesh, which evoked unsettling memories of India’s last serious outbreak of communal violence, in 2013. Sixty-five people died on that occasion, and thousands of Muslims sought refuge in Kairana. Now the B.J.P.’s member of Parliament for Kairana claimed that hundreds of Hindus had fled, fearing for their lives. The charge was subsequently discredited, but Shah seized on it in his speech in Allahabad, warning of a mass exodus of Hindus if the Samajwadi Party retained power.

Three weeks later, on July 5th, Modi appointed three new ministers from Uttar Pradesh to his cabinet, a move generally interpreted as an appeal to caste-based voting blocs in next year’s elections. One is a Brahmin, one a member of the “other backward castes,” and the third a dalit (the term that has replaced “untouchable”).

Kanpur, with a population of more than three million, is the largest city in Uttar Pradesh and a microcosm of everything that ails urban India. The British once called it “the Manchester of the East,” for its booming textile mills, but these have gone into steady decline, replaced by tanneries, one of the most polluting industries in the world. As in Varanasi, about a fifth of Kanpur’s population is Muslim, but Muslims wield greater political influence here, because the city’s tanneries, nearly all Muslim-owned, bring in more than a billion dollars a year in export earnings.

One muggy afternoon in Kanpur, I went down to the Massacre Ghat, which is named for three hundred British women and children who were killed there in 1857, during a rebellion against the reign of the British East India Company, referred to locally as the First War of Independence. The river was a hundred yards from the steps, across a bleak expanse of silt. Raw sewage leaked onto the beach from a drainage channel. Cut off from the river, it had collected in a stagnant, bubbling pool. Groups of children were playing in the shallows of the river, and women clustered in circles at the water’s edge, preparing offerings of coconuts, fruit, and marigold garlands.

Kanpur has four hundred and two registered tanneries, which discharge more than two-thirds of their waste into the river. Most are immediately downstream from the Massacre Ghat, in a Muslim neighborhood called Jajmau. In deference to Hindu sensitivities, the slaughter of cows is illegal in Uttar Pradesh. Most of the hides that reach Kanpur’s tanneries are from water buffalo; the small number of cowhides are either imported or the result of natural death or roadkill.

Tannery owners in both the poorest and the most lucrative parts of the industry complained bitterly to me that they had been singled out for persecution because they were Muslim. “From the government side, there is nothing but trouble,” Hafizurrahman, the owner of the small Hafizurrahman Tannery, in Jajmau, told me. Hafizurrahman, who goes by only one name, has been the president of the Small Tanners Association since 1987; his tannery works with offcuts that are rejected by larger enterprises. A soft-spoken elderly man with a white beard and a suède porkpie hat, he works out of a windowless shed with rough plaster walls. When I met him, flop-eared goats and quarrelsome geese were rooting around on the floor, and the yard was strewn with pieces of dried rawhide that would be turned into chew toys for dogs. A skinny teen-age boy, bare to the waist and glistening with sweat, squelched around in a brick-lined pit, sorting pieces of “wet blue,” tinged that color from processing with highly toxic chromium salts, which leaves the leather more supple than the older, vegetable-processing method.

Hafizurrahman conceded that the tanneries do foul the Ganges, but said that the real culprits are corrupt state and city authorities. In 1994, when the city government opened a central plant to treat the tannery waste, tannery owners had to contribute part of the cost. Then the construction budget tripled and, with it, their contribution. “There were only a hundred and seventy-five tanneries at that time,” he said. “But then another two hundred and twenty-seven came up—and the government asked them to pay again. But it never upgraded the plant. They just took the money.”

In 2014, the Council on Foreign Relations named India’s judiciary, police, and political parties the three most corrupt institutions in the country. Local officials commonly skim off a substantial percentage of the fee paid to private contractors working on public-service projects, such as water supply, electricity, and sewage treatment. “It’s almost legal,” Rakesh Jaiswal, the head of EcoFriends, a small environmental group in Kanpur, said. “If it’s thirty or forty per cent, it’s not corruption—it’s more like a right. Sometimes all the money is pocketed by the authorities, a hundred per cent, and the work takes place only on paper.” I asked if things had improved under Modi, and he shook his head. “Not even one per cent has changed,” he said.

Taj Alam, the president of the Uttar Pradesh Leather Industry Association, had another complaint. Alam’s tannery, Kings International, makes high-end saddlery for export; situated in Unnao, a small town a dozen miles from Kanpur, it is surrounded by manicured gardens and walls draped with bougainvillea. In his ornate, air-conditioned office, Alam noted that the government shuts down the tanneries each year, sometimes for several weeks, to avoid polluting the river during India’s greatest religious celebration, the Hindu bathing festival at Allahabad, a hundred and thirty miles downstream. This costs the industry tens of millions of dollars, Alam said. “But you have ten million people shitting in the river, urinating there, throwing stuff on the ghats. The tanning sector is maybe 99.99 per cent Muslim. Tell me, has the government imposed any treatment-plant order on any other industry?”

Alam told me that he was worried about next year’s state elections. “If there’s a B.J.P. state government, they can do whatever they want,” he said. “When someone has an absolute majority, it can be misused. And it is being misused.”

leaning up the tanneries of Kanpur has proved just as intractable a problem as cleaning up the sewers of Varanasi. I spent a day in the tannery district with Rakesh Jaiswal, the head of EcoFriends, touring the evidence. Jaiswal, who founded the organization in 1993, is in his late fifties, and has silvery hair and a courtly manner. We stopped at a cleared plot of land about a quarter of a mile from the river, where the detritus of the leather industry was heaped in large piles. Some were offcuts of wet blue. Others were made up of scraps of hide with hair and bits of flesh still attached, surrounded by clouds of buzzing flies. A laborer was hacking at the muck with a three-tined pitchfork. When he was done, it would be sold to make chicken feed and glue. Nearby, an open drain carried a stream of tannery waste down a gentle slope to the Ganges. The odor suggested a mixture of decomposing animal matter, battery acid, and burned hair.

In 1998, Jaiswal brought a lawsuit against the central government and a number of polluting industries, and a hundred and twenty-seven tanneries were closed. Many were allowed to reopen after installing a primary-treatment plant, but Jaiswal told me that the levels of chromium pollution in tannery wastewater were still as much as eighty times above the legal limit, suggesting that the plant owners were not spending the money to operate them, and that the new regulations were only spottily enforced. From the tanneries, the wastewater is pumped to a central treatment facility, which was built in 1994. At the plant, sewage and tannery waste are combined in a ratio of three to one. After treatment, the mixture is used for irrigation. The plant handles nine million litres of tannery waste a day, barely a third of what the industry generates. When I asked the project engineer why the plant had never been upgraded, he shrugged.

Later, I drove with Jaiswal to the outskirts of Kanpur, to see the irrigation canal. It ran along an elevated berm where workers had spread out hides to dry in the sun. The treated mixture of sewage and tannery waste came gushing out of two rusted outflow pipes and made its way down the canal at a fair clip. In 1999, Jaiswal conducted a study of contamination in the villages that were using this water for irrigation; his samples revealed dangerous levels of chromium in agricultural produce and in milk. I asked Jaiswal if the situation had improved since then. “The quality of the water is the same,” he said.

The success of Modi’s cleanup effort will ultimately depend not on Uma Bharti, or even on Modi, but on less visible bureaucrats such as Shashi Shekhar, the water-resources secretary in Bharti’s ministry, who is charged with carrying out Namami Gange. Shekhar, who is in his late fifties, was trained as an earth scientist. Before assuming his current post, last year, he was the head of the Central Pollution Control Board, a national agency that is respected for its professionalism but is frequently unable to enforce the standards that it sets, because the state-level agencies responsible for meeting them are typically corrupt or incompetent.

When I went to see Shekhar in his office in New Delhi last fall, he walked me through a PowerPoint presentation that he was about to deliver to the cabinet. It served as a reminder that Modi is not only an ideologue but a demanding chief executive. In 2015, India recorded a growth rate of 7.5 per cent, overtaking China. In September, during a weekend visit to Silicon Valley, Modi won commitments from the C.E.O.s of Google and Microsoft—Sundar Pichai and Satya Nadella, respectively, both Indian-born—to help bring Internet access to villages and to install high-speed Wi-Fi in the country’s railway stations. (India has the world’s second-largest Internet market but the slowest average connection speeds in Asia.) He has also introduced programs designed to make the government more accountable to the public, such as PRAGATI, a videoconference platform where Modi grills government officials on citizens’ complaints about bureaucracy, corruption, delays in executing public-works projects, and other issues.

“The P.M. is very particular about making the system efficient, accountable, and sustainable,” Shekhar said. He acknowledged that the cleanup campaign had got off to a slow start, but said that his ministry was setting a series of deadlines that would soon begin to show tangible results. He had been in Kanpur just after I left, and he said there was now a more coherent plan for cleaning up the city’s tanning industry. This included an order that each tannery install sensors to measure its discharge. Several lawsuits are also under way, including one before the Supreme Court, that could close down tanneries that exceed official pollution limits—although, as Rakesh Jaiswal noted, this has been done before, to little lasting effect.

Shekhar had also proposed a “paradigm shift” in the approach to sewage treatment. Despite the efforts of the previous government, sixty per cent of the treatment plants along the river were still either shut down or not operating to capacity, and ninety per cent failed to meet prescribed standards. Too much responsibility remained in the hands of corrupt local officials and contractors. Now the contractors would be paid only after they’d done the work. Otherwise, Shekhar said, “we found that the fellow does not put his skin into it.”

Major corporations had agreed to clean the surface of the river with trash-skimming machines and booms. The Tata Group, India’s largest conglomerate, would take on the stretch of river in Varanasi. Shekhar also planned to build communal toilets in some of the poorest riverside villages. Women were especially keen on this idea, he said, since, for privacy, they customarily go out into the fields in the pre-dawn dark or after the evening meal, when they are vulnerable to snakebite and sexual assault.

Some elements of the cleanup shouldn’t be difficult to execute. Sewage-treatment plants that are already under construction will be completed. Recently, Shekhar e-mailed me to say that work on cleaning the ghats in Varanasi, Kanpur, and Allahabad had begun on schedule; for a company with Tata’s resources, this is not a particularly challenging assignment. Shekhar also said that the government had spelled out the terms of what it called a “hybrid annuity” plan for payments to contractors working on the new sewage-treatment plants and other public-works projects. But will tinkering with financial incentives truly reduce bureaucracy and corruption, especially in parts of the country where state authorities aren’t under the control of Modi’s political party?

Modi’s greatest asset may be his conviction that he can inspire change through sheer dynamism. But this may also be his biggest liability. “The expectation is so huge,” Shekhar said. “Even bureaucrats have the perception of him as Superman.”

Shekhar acknowledged that Namami Gange would not fully restore the river. The hydropower dam at Tehri would remain, as would the nineteenth-century diversion canals. In lower stretches of the river, where the flow is already severely depleted, it will take decades to address the inefficient use of water for irrigation. Even so, he said, “never in the past has a government initiated a project of this magnitude. I am putting myself under great pressure as far as targets are concerned. But if you do not see high, you do not reach midway.”

Early one morning in Varanasi, I went down to Assi Ghat to meet Navneet Raman, the chairman of the Benares Cultural Foundation and the scion of a family that traces its ancestry back to the finance minister of a sixteenth-century Afghan king. Raman is an environmentalist on a modest scale, planting trees and offering to compost the flowers left by worshippers at the Golden Temple, the most important temple in the city—an offer that the priests had declined.

We hailed a boatman to row us across to the east bank of the Ganges. It is considered to be an inauspicious place; anyone unlucky enough to die there will be reincarnated as an ass. As we pulled away from the steps, the rising sun flooded the curving waterfront of ghats, temples, and palaces. When we arrived at the other side, Raman reached into a bag and scooped out a handful of shiny purple seeds the size of pistachios. They were seeds of the tropical almond, Terminalia catappa, and would grow into what is known locally as “the sewage tree,” because it can filter heavy metals and other pollutants out of standing water. We walked along a narrow strip of scrubland, above the flood line, scattering the seeds left and right.

“Most people come to Benares to pay last respects to the memory of their near and dear ones who have passed away,” Raman said. “So I thought that on this bank of the river we could make a forest of remembrance. This is my guerrilla warfare. I am not doing it for Mr. Modi.” Raman imagined leafy gardens and walkways, and benches where families could sit and look across the river at the beauty of the temples and the ghats. But he acknowledged that this vision lay far in the future.

I asked him if he ever grew discouraged by the slow pace of change. He shrugged and said that all he could do was place his trust in Shiva. “India is a land of discouragement,” he said. “If you’re not discouraged by the harsh summers, then you are discouraged by the cow eating your plant, or the motorbike or tractor or car that is running over your plant, or the neighbor who is plucking the leaves from it just for fun as he is going by. If you can’t deal with discouragement, India has no place for you.”