Bio-toilets: Sanitation super hero to our rescue
The buzzing of the crowd, vendors ringing their bells, calling out their wares. The intoxicating smell of vada pav overpowered by a baser and horribly unpleasant aroma. Human faeces in clumps on the railway track and flies everywhere. I was at Kurla station to greet a friend. That said, I could be at any long distance railway station in India and it would look and smell the same.
The Indian Railways are quite possibly the biggest enablers of open defecation in the world. Every day, thousands of trains ferry millions of travellers from one destination to another. With hundreds of people in each coach using the same facilities, it’s no wonder that train toilets get filthier as the journey gets longer. The toilets are little more than holes in the floor, and waste is directly dumped on to the tracks, where it lies and festers at the mercy of our climate, rotting, degrading and sheltering disease-causing agents.
Recently, in an ambitious attempt to reduce the impact of all this waste on the ecosystem and reduce the incidence of disease especially at train stations, the Central Railways replaced the old hole in the floor toilets with bio-toilets.
So what are bio-toilets? And why do I think they are superheroes?
Bio-toilets use microbial technology to degrade human waste quickly and efficiently with no adverse impact on the ecosystem. Sounds brilliant, doesn’t it?
Bio-toilets were first developed by DRDO (Defence Research and Development Organization), Gwalior for our soldiers patrolling at the line of control in Kashmir. The cold climate slows down the natural degradation process of faeces. Before bio-toilets, the soldiers on LOC used pit latrines and would then incinerate the waste generated. In a place, where survival depends upon the success of camouflage, following a practice like incineration can be fatal.
A typical bio-toilet design consists of an underground bio-digestor tank with a consortium of microbes that convert organic matter from human waste into water and odourless gas methane.
While bio-toilets have successfully solved sanitation problems at the LOC, the technology has far-reaching potential especially in a country like ours. Almost fifty percent of the population still does not have access to indoor or public sanitation facilities resulting in an approximate 65,000 tonnes of excreta being released into the environment every day.
In 2008, Indian Railway Ministry took a revolutionary step forward when they decide to solve the problem of waste generated on railway tracks and platforms due to the existing toilet system by converting conventional toilets into bio-toilets.
For railways, some necessary structural modifications were made to the core design of bio-toilets. In a typical bio-toilet for a railway coach, specialised bacteria are embedded in the two-compartment tank of bio-digester attached below the train. The waste from the toilet falls in the first compartment, where the same psychrophilic bacteria attack the organic matter with degrading enzymes. The bacteria eat up the all organic matter present in the human faeces and convert it into odourless gas and water. These bio-toilets are a low maintenance and economical way of dealing with a significant amount of human waste generated in trains.
In India, there are several rural and urban slum communities who do not have access to proper sewerage and solid waste disposal. Clogged toilets, open septic tanks and open sewage lines in such area are an open invitation to various diseases.
These toilets too require some structural modifications to make them suitable for household usage. The underground bio-digestor septic tanks – embedded with specialised bacteria sheets – are built below the toilets. The debris from the toilets percolates through the sheets where bacteria degrade the organic matter. The bio-toilets convert the foul smelling human waste into odourless gas and water that can be released at no risk to the ecosystem into the sewage system.
Another benefit is that the methane produced is combustible and can, therefore, be used for various household chores such as cooking, heating water etc. Moreover, the leftover from the process is nitrogen-rich compost that can also be repurposed as manure for gardening.
PUBLIC SANITATION FACILITIES
Open defecation causes the unchecked spread of disease-causing agents such as mosquitoes, flies and bacteria and contaminates the ground and surface water. Nearly 75 percent of India’s surface water is highly polluted and, therefore, deadly for human consumption. Epidemics of cholera, typhoid and dysentery are the results of drinking such water, especially in slums.
India has one of the biggest slum populations in the world. For most living in these communities, a toilet is a luxury rather than a necessity! A report by the Slum Sanitation Programme states that only 37 percent of the slum dwellers have access to public sanitation facilities. However, more than 80 percent of these toilets are unusable either due to improper sewerage, over-utilisation or poor maintenance.
In 2014, the Government of India launched Swachh Bharat Abhiyan in what is seen as a massive campaign to end open defecation by 2019. They started building community and public toilets for all Indian citizens. A number of private and non-governmental organisations have also partnered with this program to support the government’s initiative.
The challenge, however, will not be addressed with infrastructure alone. A recent study from the Indian Institute of Technology, Madras, has concluded that bio-toilets in trains are nothing more than septic tanks! They found out that the bio-digesters are failing to treat the human waste because of its large quantity. “Just like septic tanks from any public toilet in India, the bio-digesters are nothing but a home of accumulated slush (water mixed with human faces)”, says IIT professor Ligy Phillip.
The game-changer that makes bio-toilets effective is the consortia of microbes that are used to degrade waste. Bio-toilets, in combination with education on correct usage, proper maintenance and an effective consortium of bacteria can definitively solve India’s open defecation problem. It’s time we went beyond just infrastructure to solve this mammoth problem.