The ₹166-crore state-of-the-art sewage treatment plant (STP) project that Cochin Smart Mission Limited (CSML) has envisaged near the Fort Kochi Taluk Hospital to scientifically treat sewage from divisions 1 to 5 of the Kochi Corporation is in doldrums owing to stiff opposition from local residents.
It is despite the unusually high prevalence of water- and air-borne diseases in the area spread over 2.70 sq.km, which includes heritage tourism locales in Fort Kochi and Mattancherry. Over 42,000 people live in the densely populated area.
Grey water and sullage from septic tanks and pits are discharged into roadside stormwater drains, resulting in slow-moving canals and sea, posing a public health hazard and degradation of environment. It is because West Kochi never had a piped sewerage and centralised treatment system. It was in such a perilous situation that a 6.5-million-litre-per-day (mld) treatment plan was mooted in a 45-cent vacant area near the 10-metre-wide Kalvathy canal, whose width too could be used by covering it with a concrete structure, CSML sources said.
“The proposal was to lay a 72-km-long pipeline to collect sewage from households and treat it at the STP which would bank on the widely proven sequential-batch reactor [SBR] technology. It would also have a well-maintained aerobic treatment system which makes good use of air that is pumped into the plant to prevent bad odour. In addition, the plant will have high boundary walls and a green buffer zone around it. This is in stark contrast with the present situation when untreated sewage is contaminating groundwater and canals, while toxic methane and hydrogen sulfide from it are polluting the ambient air,” they added.
The STP was to rely on a Dutch technology-based vacuum sewerage network, which is rather new in India where most cities have gravity sewer network. “The vacuum sewage system is ideal for West Kochi, which has a flat terrain and high water table and is densely populated. The sewage that gets collected from houses is vacuumed immediately, and it reaches the plant in less than a day. This is in contrast with the process taking days to reach conventional plants, by which time it gets difficult to treat, as the old sewage becomes septic,” the sources said.
In addition, pipelines up to 25 cm diameter can be used as against one-metre-wide or bigger pipelines used in conventional systems. This is apart from the fact that maintaining SBR plants is much less expensive than conventional ones.
Expressing concern at the continuing opposition to the STP, Mayor M. Anilkumar said most people in the locality opposed the venture despite attempts by people’s representatives, including himself, to convince them that it was in accordance with a new technology.
Kalvathy division councillor T.K. Ashraf said people feared that the plant in a limited space would have an adverse fallout on the taluk hospital and schools nearby. “Similarly, a ₹200-crore STP, which was mooted under the JnNURM-KSUDP scheme in five acres of the GCDA land at Mundamveli, had to be abandoned after the land was filled and pipelines were laid in some areas in the wake of a few people moving the court citing threat to mangroves,” the councillor added.
In this circumstance, the CSML could think of relocating the proposed STP to other vacant spaces, Mr. Ashraf added.
