The scheme claiming to be on the verge of completing toilet construction for all rural households, a government-commissioned survey shows that just over a quarter of rural toilets use this twin-pit system.

The waste from the remainder of rural toilets could create a new sanitation nightmare harmful to health and the environment, and even pushing a new generation into manual scavenging.

About twin-pit system:

Under the twin-pit system, two pits are dug with honeycombed walls and earthen floors which allow liquid to percolate into the surrounding soil.

When one pit is filled and closed off, waste flow is transferred to the second pit, allowing waste in the first pit to be converted into manure after a year or two.

Data from the National Annual Rural Sanitation Survey 2018-19, shows that just 26.6% of rural households use the recommended twin-pit system to dispose of excreta from their toilets.

Septic tanks are the most popular option, with 28% of toilets connected to a septic tank with a soak pit and 6% to a tank without a soak pit.

The twin pit has been promoted by the Ministry of Drinking Water and Sanitation as well as the World Health Organisation as an in-situ sanitation system which claims to bypass thorny issues such as caste purity, as owners will be dealing with manure, not excreta.

With the government intensively promoting twin pits over the last two years, it is unsurprising that the highest ratio of twin pits are found in States which have only recently completed toilet construction.

Sludge management

For the more than 70% of toilets without twin pits, a faecal sludge management system is desperately needed.

It’s not enough to connect [the toilet] to a drain if it is simply emptied out into local land or ponds. It will lead to large-scale pollution of groundwater.

A 2018 survey of 30 cities and towns in Uttar Pradesh by the Centre for Science and Environment found that 87% of toilet waste is dumped into water bodies and farm lands.

The same Dalit communities which have traditionally been forced into manual scavenging are likely to end up in sanitation work to clean these tanks and any newly built rural sewerage systems.