What are Evapotranspiration Toilets and why are these the best alternate vis-à-vis conventional toilet systems?
The concept
The Evapotranspiration Toilet is a composting waterless toilet or rather a water-efficient toilet. As part of dry sanitation, the system does not use water to transport human faecal matter. On the contrary, they keep the human excreta or potential pollutants out of the underground water bodies and waterway system. Thereby acting as one of the best solutions to stop further degradation of the general environment. Plus, they reduce various problems associated with on-site septic tanks.
Compost toilet like the evapotranspiration toilet require abundant space below the toilet floor. This space is where a holding tank or pit is constructed where the excreta undergoes a composite biochemical reaction involving micro-organisms, acidity, temperature, and desiccation by invertebrates over a period of time.
Details of the structure of the tank
The tank of the toilet has a non-porous lining. The tank has different layers and sub-structures made up of stones, broken bricks and sand etc. The function of these layers is to convert about 70% of the excreta into biogas through evaporation, transpiration and anaerobic digestion. The biogas moves out of the back standpipe through capillary action. The balance 30% converts into organic compost and rises to the top. The compost is then absorbed by the roots of plants nearby. Banana is one of the most common plants that is planted on the surface of such tanks. Evapotranspiration is the process through which the liquid waste either evaporates from the soil surface or transpires through plants and trees.
Benefits
The Evapotranspiration Toilet is an eco-friendly toilet that basically ensure four things: –
- It is hygienic for its works on a self-cleansing model where the faecal waste and urine gets filtered and does not require manual intervention.
- It is a low-cost and investment affair and also requires minimal maintenance. Recycled materials are used mostly in building these toilets.
- It is green and is fair on the environment for it cannot lead to any kind of contamination of the soil or water nearby. These toilets also require a minimal amount of water.
- It is easy to construct, simple to use and easy to repair in case the toilet is damaged.
One of the biggest advantages of this type of toilet is that it does not require any kind of human interference to clean the tank. This makes the toilet an accessible and hygienic concept. The other types of conventional toilets, usually constructed in the rural areas of the country, involve regular cleaning and maintenance of the septic tank.
In a country like India where more than 600 million people still defecate in the open because of the absence of proper toilet infrastructure in their homes and neighbourhood, the Evapotranspiration Toilet or sustainable toilet seems like the perfect answer. It is economical and it helps remove the social stigma that is associated with open defecation and respects the privacy requirements and dignity of men, women and children
The origin
The Evapotranspiration toilet system was developed and used in western countries. US and Brazil have seen the technique being practised to a great extent in the last twenty to thirty years. Presently the method is largely being used in the northern parts of Brazil like Ceara state. It has also paved the way for sustainable tourism.
Presence of this green toilet system in India
The Evapotranspiration or eco-friendly toilet was first built in few villages in Uttar Pradesh. Named as ‘Better Village Better World’ undertaken by Safalgram, there have been at least 180 plus eco-friendly toilets built till date in about 10 villages of the country. The project has primarily seen the development work happening in the Jagatpur Village in the Bulandshahar district, Usuri in Aligarh district, Ayodhya Ka Purwa in Faizabad district, Jimidar ka Purwa in Gonda district and Dhakolia village in Bijnor of UP where such eco-toilets have been constructed. Five demo toilet units have also been made in the Kakrana and Dhaulana villages in Ghaziabad recently.
The Evapotranspiration Toilets in India typically have one tank that is 5 feet tall, 9 feet in length and 2 feet in width. The toilet costs approximately about Rs. 10000 compared to the toilets built by the government of India under the Swachh Bharat Abhiyan scheme that is priced about Rs. 17000.
Safalgram and team
Safalgram is involved in providing cost-effective and eco-friendly development solutions to villages in India under the ‘Better Village Better World’ initiative. The team believes in innovating and providing novel and user-friendly solutions to the villagers and is actively involved in the construction of EVT toilets – a concept that has won accolades from the Indian government as well as permeable roads and drinking water filters. The green toilet initiative taken by the Safalgram team to make India an Open Defecation free zone consists of three core team members: –
- Marta Vanduzer-Snow – Marta, a native of Boston has worked with the Rajiv Gandhi Mahila Vikas Pariyojana as a volunteer. She is the co-founder and director of Safalgram. She has worked and volunteered in the rural areas of Uttar Pradesh. She has studied at the New York University and years of experience in social upliftment related work.
- Amitabh Bhattacharya – an ad maker by profession, Mr Bhattacharya is the co-founder and director of Safalgram. He has worked with top-notch brands like Pepsi, Coca Cola and Levi and has a production house called Nomads based in Mumbai.
- Pawan Singh – is the third co-founder and program coordinator. He is the man who oversees all projects and programs undertaken by Safalgram.
Surwahi Social Ecoestate Kanha and Evapotranspiration Toilet
Surwahi Social Ecoestate Kanha, an upcoming homestay on the outskirts of Kanha National Park is an exemplary model of alternate and sustainable tourism. The eco-friendly project has meticulously been designed and constructed in a way that it keeps all its surrounding natural elements intact along with the use of eco-friendly techniques of construction. It is also the first of its kind that has worked with Safalgram to have the maiden Evapotranspiration Toilet built in the entire state of Madhya Pradesh. The common washroom block built under Phase 1 of the homestay is an EVT toilet – the first one in the state on its premises.
