Pathashaala: The Tamil Nadu school that is turning waste into rich soil

It is 2 October, Gandhi Jayanti. It’s one of the two mornings each year, 2 April and 2 October, when Pathashaala, the Krishnamurti Foundation India school in Chengalpattu district, 80km south of Chennai, opens its dry toilets and harvests the compost. Each chamber takes roughly six months to turn waste into soil.

Pathashaala is one of the few places in India where dry toilets have been used campus-wide for over a decade. Comparable efforts exist in Auroville (Puducherry) and in Ladakh, but this is arguably the longest-running successful effort. In fact, educator Sonam Wangchuk visited Pathashaala in 2020 to study its system for his own residential schools. Elsewhere, public or government deployments have struggled to sustain daily practice. Pathashaala has used no flush toilets since 2010; the system has held through fifteen years of student cohorts. Disclaimer: My daughter studies here.

J. Krishnamurti, the philosopher-thinker on whose ideas the school is based, once asked what people would do when machines take over everything human thought can do. It’s particularly pertinent in the age of AI. Machines can do most things better, faster, cleaner. But they cannot ask why. They cannot listen. They cannot touch soil that was once waste and know that everything returns to the earth. These toilets remind one of this.

Pathashaala sits on the floodplain of the Palar, a river locals say is “too wide for the water it now carries." About twenty feet beneath the clay lies a shallow aquifer that supplies the school’s two borewells and some nearby farms. “These bores give clean water; bores farther west draw brackish water," says G. Gautama, Pathashaala’s founding head and former principal of The School, KFI, Chennai.

The foundation began buying parcels here in 2002—32 acres first, then the remainder as state purchase rules changed. “Where the boys’ dorms stand now, people used to distill liquor," says Gautama. “The place was thorn scrub and water stagnated in pockets. A single shower could trap a truck. You couldn’t plan anything."

The first building flooded under two feet of water after rain, so the architects moved the campus to higher ground on the southern edge and cut west-to-east drains that let water run off. Sudhakar Mahadevan, the architect from 2006, travelled to Wardha and Hyderabad to study low-energy systems and re-worked the plan. Work began in 2008; phase one—about 25,000 sq ft—took roughly two-and-a-half years. The school opened in August 2010 with 14 students; numbers rose to 120 by 2019, dipped to about 95 post-pandemic, and stands at about 104 students and 25 teachers today. Capacity is capped at 130.

Climate sets the timetable too. November and December—cyclone months—became a scheduled break. The toilets came from the same logic as the rest of Pathashaala’s design: live with what the land allows.

“Ordinary flush toilets were out of the question," says Gautama. “The aquifer here lies barely twenty feet below the surface. A flush system would have polluted it within months. And in the monsoon, underground tanks would have overflowed into the channels, contaminating downstream water bodies."

The search for an alternative began in 2007, three years before the school opened. That year Dagmar Albrecht, a German educator from Brockwood Park School (Krishnamurti Foundation’s UK campus), arrived as a volunteer. She spent a year studying the site and proposed an unfamiliar solution: urine-diverting dry compost toilets (UDDTs), a system that separates urine and faeces, keeps the chamber dry, and lets bacteria compost waste into safe soil within six months.

Albrecht located a manufacturer in Ahmedabad and persuaded them to send sample units. “We had a showroom of toilets in our visitors’ room," Gautama recalls. “Nobody dared to use them."

To prove the idea, he installed one in his house on The School KFI campus in Chennai in 2007. He used it for six months. A year later, when he and his son opened the chamber, what they found changed everything. “It smelled like rain," Gautama says. “That was the moment of proof." In 2008, he invited 30 teachers at The School KFI to witness a harvest. When one teacher, Shobhana Nataraja, picked up the compost and said, “It smells like fresh earth," the phrase became an emblem of acceptance. The first 14 students and 5 teachers who moved in to Pathashaala on 19 August 2010 used dry toilets from day one.

When the Ahmedabad-based manufacturer shut down in 2011, the crisis forced invention. “We had no experts," says Gautama. “We became the experts." Pathashaala started designing and fabricating its own models.

The first generation, made of stainless steel, was elegant but impractical—hard to clean, easy to smear. “Beautiful, but hopeless," Gautama says. The team of teachers, masons and students tried fibreglass, cement, and paint-bucket prototypes, fabricating parts locally with a metalworks shop called V-Steel. They kept improving airflow, slope and surface finish until, by 2015, they found a lasting solution: Cuddapah-stone trays—flat slabs of local limestone with a 10cm opening and detachable seat. The design needed surface cleaning, could be used in Indian or Western style, and cost a fraction of commercial models.

During these years of trial, the school continued uninterrupted. “Every new student went through a dry-toilet orientation," Gautama says. By 2013, when finances were tight and purchased units unavailable, even Gautama considered giving up. Encouragement came from the students. One senior told him, “No, anna! One of the nicest things here is the dry toilet. We can’t let this go. Let’s design our own."

Over time, Pathashaala’s learner-educators (students) and educator-learners (teachers) co-created a functioning toilet. As of 2025, the campus has 69 toilets across dorms and staff quarters, all urine-diverting and water-free. Each one is locally built, maintained, and harvested twice a year—on 2 April and 2 October.

“Everyone uses the same toilets—students, teachers, kitchen staff," Gautama says. “If equality means anything, it must show in where you sit, what you eat, and where you go." Some students have told him they felt uneasy using flush toilets at home. “It feels wrong," one said, “to use clean water to wash away what could become soil."

By the school’s tally, the dry-toilet system saves roughly half a million litres of flush water a year at full strength—about 540,000 litres in 2019 alone (15 litres per flush, 250 days).

Pathashaala has stayed small—around 120 students and 25 adults at any time, from Classes 5 to 12. Each dorm houses twelve children; each classroom holds mixed-age groups. Everyone on campus—students, teachers and staff—recognises everyone else. As in other KFI schools, adults address one another as akka and anna—sister and brother. Everyone eats the same food at round tables, introduced after a student said square ones left people out. Seats are randomised so students meet someone new at each meal. It’s common to hear them note that the vegetables on their plates grew from compost they once helped harvest.

When I dug into the compost that morning, I thought about how lightly we use the word waste. In Shivpuri, Madhya Pradesh, on 26 November 2019, Constitution Day, activist Abhay Jain walked into the public health engineering department office with others, carrying lumps of human excreta in their hands, to protest the continuing practice of manual scavenging. He told me about sanitation workers who were made to clean open drains behind government quarters with bare hands and a single shovel. “When we complained," he said, “officials said equipment had been provided. They didn’t even know the difference between manual scavenging and sewer cleaning."

That image returned as I lifted a tray of compost that had once been excrement. Here, the act was not punishment or protest. It was learning. I understood what these dry toilets truly mean. They are not only about saving water or protecting an aquifer; they are about reclaiming dignity and equality. It is a way to think about water, labour, and what it means to be responsible for what we produce.

By noon, the trays are stacked, the pits closed. The soil will rest for six months. On April 2, they will open it again. It will smell, as always, of wet soil after rain.

Pankaj Mishra is a journalist and co-founder of FactorDaily, reporting on the intersections of technology, environment, and culture.