Railways’ plan to fit all coaches with bio-toilets will help it leave an odourless trail


Indian Railways carries over eight billion passengers a year in 55,000 carriages. Even if a small percentage of this number uses the toilets, the public sector entity sure leaves a whole load of shit for people living along its lines to deal with everyday.

The human waste that slides onto the tracks as a traveller uses the moving train’s toilet is not only harmful, as it can enter local groundwater systems, but is also a carrier of the deadly polio virus. The water that spills over also corrodes the rails and damages the cement sleepers.

All this is set to change soon with the railways planning to retro-fit 1.40 lakh bio-toilets by mid-2017 in all its coaches by accelerating its Swachch Rail-Swachch Bharat programme.

These bio-toilets, designed by the Defence Research and Development Establishment, a defence laboratory in Gwalior, is being mass produced by several private units across the country.

How do bio-toilets work?

These bio-digester toilets completely eliminate the problem of solid waste being emptied onto the ground as it has a two-compartment tank attached below the train toilet. These digesters with bacteria inside them break down the faecal matter into odourless and pathogen-free gas and liquid, which is basically carbon dioxide, methane and water. In the first canister into which the faecal matter falls, the bacteria get to work and fill up the second canister, which can then be emptied anywhere.

These bio-digesters require to be maintained at constant warm temperatures and the metal container helps it maintain it through a combination of geothermal and microbial heat even during winter.

Green corridors announced

Railway Minister Suresh Prabhu has already announced that tracks on many routes are free from human waste spilling out of toilets and onto the tracks. Under Western Railway, two routes in Gujarat earlier this month were declared as green corridors. The routes are the 141-km Okha-Kanalus and 34-km Porbandar-Wansjaliya stretch. Around 650 coaches that run on these two routes have been fitted with bio-toilets. More such green corridors are expected to be announced by the end of this financial year.

At a recent Swachch Abhiyan meet in Delhi, the minister had said 14,000 bio-toilets have already been installed in trains this year and 16,000 more such toilets will be fitted onto coaches by the end of this fiscal. In fact, the whole process has been fast-tracked as the original timeline to install bio-toilets was 2019-2020.

On premium trains, these bio-toilets are also vacuum-based, like an airline toilet, where little water is used to flush and it is suction-based. These vacuum toilets are being fitted onto Rajdhani, Shatabdi, Duronto and other long-distance superfast trains.

Taken to court

The unhygienic practice of commodes with a direct opening onto the ground had been in practice since it was inherited from the British Raj, and little has changed since independence. This utter lack of hygiene and the serious health challenges it posed to communities living near the railway tracks troubled a Kerala-returned doctor so much that George Joseph Themplangad dragged the entity to court in 2010.

In its defence, the railways said it was developing several technologies such as a bio-digester in association with the DRDO and a latch-based system, where toilet waste would be disposed only when the trains moved in excess of 30kmph. This system is called Controlled Toilet Discharge System, which will also be fitted with a bio-digester.

Dr Themplangad, who returned to his native Chenganasserry after a stint in the US, had estimated that there would be at least 14,000 tonnes of faecal matter discharged from moving trains and rail stations every day, but a Rail India Technical and Economic Service (RITES) study had put the figure at 6,000 tonnes per day.

The railways also told the court that it had planned to increase its capacity to recycle water by setting up plants. The 2012-13 Railway budget also had stated that the railways planned to install 10,000 bio-toilets that year, but delays continued till the stress on Swachch Bharat was laid by Prime Minister Narendra Modi in 2014-15, which accelerated the railway programme.

How it all started

DRDE, Gwalior, under Dr Lokendra Singh, had originally developed the human waste degradation units to help soldiers who were finding it difficult to defecate in Siachen and other inhospitable areas where toilets were out of the question due to lack of piped water supply.

So the DRDE developed a waterless unit, where the bacteria, originally collected from Antarctica and grown in its labs, gorged on the solid waste and converted it into odourless effluent consisting of carbon dioxide and methane gas, which could also be used to light up kitchen stoves.

The same technology was adopted for the Indian Railways by tweaking it a bit and it was also proved that this odourless broken down parts and water that were discharged from a moving train were harmless to the immediate environment.