Mahalaxmi Municipality of Lubhu in Lalitpur district has installed the country’s first faecal sludge treatment plant for safe management and disposal of sludge collected in septic tanks and around 400 emergency toilets set up in around Lubhu after the earthquakes last year.

The plant will come into operation from Thursday.

The Environment and Public Health Organisation (Enpho), in collaboration with local authorities, is launching the country’s first-ever faecal sludge treatment plant to mark the silver jubilee of Enpho.

The plant has the capacity to treat sludge generated by septic tanks of around 200 households every day.  

“Management of faecal sludge is a big challenge for the Kathmandu valley as almost 95 percent of it comes from the sewerage and septic tanks and ends up in the river system,” said Ritu Rajbhandari, sanitation engineer at Enpho.

Majority households of in Mahalaxmi Municipality depend on septic tanks and pit latrines. After the earthquakes last year, temporary toilets were built around temporary shelters, and the faecal sludge generated from there needs to be properly treated, or else they could pose serious health hazards.

Without a proper disposal mechanism and treatment facility before the final disposal, the sludge that ends up in the river system has not only contaminated the water system but also has threatened public health.

In Nepal, only 30 percent of the urban populations have toilets connected with

sewerage line while 48 percent are still connected with septic tanks, and the remaining practise open defecation, according to the data from the Central Bureau of Statistics.

 According to Rajbhandari, the faecal plant installed in Lubhu is a pilot project that aims to treat the sludge generated from the septic tanks of temporary toilets installed after earthquakes, and reuse the end products such as bio-gas, treated sludge, compost manure and treated water obtained after the treatment process.

The treatment plant consists of a feeding tank, two bio-gas digestors, stabilisation tank, integrated anaerobic baffle reactor and anaerobic filter, planted sludge drying bed, planted gravel filter and collection tank.

Once the latrine waste is collected by the tankers and brought to the treatment plant, the waste that consists of sludge and waste water is put in the feeder tank. The sludge is further sent to the biogas digestors where the bacterial reaction takes place, while the waste water from the feeder tank goes to anaerobic reactor and an aerobic filter, further to the gravel filter and then the treated waste water is collected in the collection tank.

“The treated sludge and treated waste water obtained after the treatment will be used in agriculture as manure and nutrients,” said Bipin Dangol, senior director, Knowledge Management Division at Enpho. The plant is installed with the support from local authority, Shaligram Child Home, a local non-governmental organisation, along with the technical and financial support from Consortium for DEWATS Dissemination based in India and BORDA, a German non-profit organisation.

It is estimated that the Kathmandu Valley generates around 122,000 tonnes of faecal sludge every year, and almost 95 percent of this waste ends up in rivers without any treatment.