Non-sewered sanitation system in Odisha | DTE Water series

Water, one of the most important ingredients to create and sustain life, is under threat. Megacities and towns around the world came into existence and sustained around rivers and lakes. But rising urban population means a rise in waste and wastewater. 

India will need 1.5 trillion cubic metres water by 2030, according to the Central Pollution Control Board. How can the gap between water demand and supply be bridged? Reuse of treated sewage can decrease water demand from aquatic sources. But this solution is not as easy as it sounds.

India generates about 73,000 million litres per day (MLD) of sewage whereas the installed capacity of STPs is around 32,000 MLD (43.9 per cent), according to the report. Odisha was one of the worst states in this regard, but the Odisha Water Supply and Sewerage Board (OWSSB) came up with a solution that is not only working but has also become a model for other states to replicate. This solution is called Odisha’s Faecal Sludge and Septage Management (FSSM).

Faecal sludge (septage) is the slurry that contains both solid and liquid waste that accumulates in onsite sanitation systems (OSS) for example, septic tanks. It is raw or partially digested slurry that results from the collection, storage or treatment of combinations of excreta and blackwater, with or without greywater. 

Earlier, the construction and management of OSS were left mainly to ineffective local practices and there was a lack of holistic septage management practices. Dhenkanal emerged as one of the first municipalities in Odisha to construct a faecal sludge treatment plant. 

Consequently, Odisha rapidly embarked on a journey to achieve United Nations-mandated Sustainable Development Goal number 6 — clean water and sanitation for all in its urban areas — by covering all urban local bodies under FSM. But there was one big problem. No one knew how to implement FSSM.

In Bhubaneswar, there are two septage treatment plants of 75 kilolitres per day (KLD) capacity each. The one at Basuaghai is even expandable to 150 KLD capacity. Other than the plant, self-help groups also take great efforts to maintain the park and leisure area. The idea is to develop the plant as an educational and practical experience and not just a place where the city's dump gets collected and treated. 

For the coastal town of  Puri, OWSSB installed a co-treatment unit at the existing 15 MLD STP situated at Mangala Ghat. This was done to fast-track faecal sludge management along with sewage.