Railways grappling with toilet technology

By Srind Jha

A new kind of toilet using bacteria to break down human excreta has been deployed in Indian trains over four years to 2017, at a cost of Rs 1,305 crore, but this toilet is no better than a septic tank, the Indian Institute of Technology-Madras (IIT-M) has concluded after a two-year long study.

As many as 93,537 “bio-digesters” — as the toilets are called — have been installed in mainline express and mail trains by the Indian Railways. These are small-scale sewage-treatment systems beneath the toilet seat: Bacteria in a compost chamber digests human excreta, leaving behind water and methane. Only the water, disinfected later, is let out on the tracks.

However, sanitation experts and various studies — including those commissioned by the railways — have pointed out that most of the new “bio-toilets” are ineffective or ill maintained and the water discharged is no better than raw sewage. “Our tests have found that the organic matter (human waste) collecting in the bio-digesters do not undergo any kind of treatment,” IIT professor Ligy Philip, who headed the latest study, told IndiaSpend. “Like in the septic tanks, these bio-digesters accumulate slush (human excreta mixed with water).” The IIT-M study was submitted last week to the Union Ministry of Urban Affairs.

Despite the criticism, an additiol 1,20,000 coaches are to be fitted with these bio-toilets, jointly developed by the Defence Research and Development Organisation (DRDO) and the Indian Railways, by December 2018. This is likely to cost Rs 1,200 crore, the railways revealed on November 2, in response to a Right to Information (RTI) request.

The bio-digester project began during the previous United Progressive Alliance regime. But the project has been speeded up under Prime Minister rendra Modi’s Swachh Bharat campaign. The idea is to meet this target in time for the celebration of Mahatma Gandhi’s 150th birth anniversary in 2019.

Indian Railways are often described as the world’s biggest toilet: It ejects around 3,980 tonnes of faecal matter — the equivalent of 497 truck-loads — onto rail tracks every day, according to a report released by the Comptroller and Auditor General (CAG) in 2013. The network has 9,000 passenger trains with 52,000 coaches with toilets that discharge human waste on to rail tracks. Covering 65,500 km across the country, these trains transport 24 million passengers every day, the equivalent of the population of Australia.

Since 1993, the Indian Railways have been experimenting with a host of technologies used worldwide to replace the open discharge system. This included vacuum toilets based on suction, commonly seen in aircraft; “controlled-discharge” toilet systems (CDTS) which allow waste to be dropped only after a train acquires a speed of 30 kmph, thus keeping stations clean; and “zero-discharge” toilets, in which solid waste is stored, evacuated and then dumped in pits for composting and the liquid filtered for recycling. In 2008, the railways decided to install the bio-digester model developed by the Gwalior-based Defence Research and Development Establishment (DRDE).

Responding to the criticism of the bio-toilet, government officials said that the flaws are being fixed. “The issues regarding the bio-digesters are of a minor ture and are being effectively addressed. Some changes (in design or execution strategies) are inevitable, as this is a continuous process,” said Saxe.

Lokendra Singh, former director of the DRDE, had, after an expedition to Antarctica, brought home psychrophilic bacteria that can survive in extremely low temperatures. The bacteria were mixed with cowdung and normal soil, which have methogens (micro-organisms that produce methane) capable of breaking down human excreta. This was then supplied to the manufacturers of rail bio-digesters.

“Because of the presence of a compound of bacteria, the bio-degradation process is set off in the toilet chambers-the bacteria eat up the organic matter (human excreta) and produce methane gas and water as byproducts,” Singh said.

But Singh’s claims of a scientific breakthrough using the bacteria from Antarctica have been questioned on several grounds, including the fact that the bacterium, as Singh admitted, has not obtained an independent or a third-party certification from an organisation such as the UIC (Federation of European Railways).

Also, DRDO does not have a patent for the design or manufacture of these bio-toilets. A patent is necessary to market a commercial product. DRDO only has a patent for the design of “railway toilet tank”, as the organisation’s website reveals.

This is not the first time the Railways’ bio-toilet project has been criticised. A 2009 study jointly conducted by the Lucknow-based Research Designs and Standards Organisation (RDSO) and IIT-Kanpur concluded that no treatment of human excreta was happening in the bio-digesters installed in railway toilets.

On September 14, 2004, DRDO scientist Y. Ashok Babu sent a letter to the then Chief Vigilance Commissioner, Pradeep Kumar, terming the bio-toilets “farce (sic) technology”.

Singh rejected these allegations. “Frustrated scientists who have never worked on the project are raising such issues,” he said.

During the last three years of the last government (2011-14), 9,350 bio-toilets were fitted in trains but the figure rose by 539 per cent, to 59,735, in the first three years of the NDA government (2014-17). In the current fincial year (2017-18), 24,215 bio-toilets had been fitted until August 30, bringing the cumulative figure to 93,537, the railways said in its RTI reply of November 2.

In this period, the cost of manufacture and fitment of bio-toilets climbed from an average of Rs 52,000 per unit to over Rs 75,000 per unit. After the imposition of the Goods and Services Tax (GST), this cost burden has spiked further, with the railways having to absorb the 18 per cent levy. (IANS)