In eight years, all trains operated by Southern Railway will have eco-friendly bio-toilets.
Now, new coaches are being rolled out only with bio-toilets, using the bio-digester concept of the Defence Research and Development Organisation (DRDO). In phases, all conventional toilets will be replaced with bio-toilets, and the Southern Railway is looking at having only bio-toilets by 2022.
A DRDO official on Wednesday conducted an orientation session for officials from various wings of the Southern Railway, especially those in charge of rolling stocks, for smooth induction of bio-toilets.
Already, the Railways have introduced 9,587 bio-toilets in 3,647 coaches out of the 48,000-plus coaches and the Southern Railway has fitted 386 bio-toilets in 966 coaches out of its 5,800-odd coaches.
A senior official of the Southern Railway said bio-toilets would ensure that there was no bad smell in toilets and no infestation of cockroaches and flies, besides eliminating the ordeal of removing human waste, which was acidic in nature and causing corrosion in coaches as well as the track.
Under the bio-toilet concept of the DRDO, the bio-digester tank in every toilet is filled with inoculums containing four types of bacteria. The water trap system in the toilet prevents air from getting into the tank, the human waste is processed by anaerobic bacteria in seven chambers in the tank and the methane gas is allowed to escape into the air.