Calcutta Metro will run fewer services along its Howrah Maidan-Esplanade section during non-peak hours from Sunday till further notice due to emergency maintenance work, an official statement said.

As per the rescheduled timings, the frequency of trains will be lesser from 7 am to 9 am, from 11 am to 5 pm and from 8 pm to 9.55 pm on weekdays, the statement issued by Metro Rail Calcutta said.

The details about the "emergency maintenance work", as cited in the statement, and in which part of the stretch, were not spelt out by the Metro authorities.

Part of the stretch passes under the Ganga and became operational in mid-March this year.

The stoppage time of each train at every station will be for 30 seconds as usual.

Meanwhile, along the Dakshineswar-New Garia line, preparatory ground work to replace the steel third rail with highly conductive aluminum third rail has already been completed at Girish Park siding, it said.

Metro Railway shall be replacing approximately 200 metres of steel third rail with aluminium third rail on Saturday night after the operational hours without affecting normal services, the statement said.

Preparatory work for pedestal base foundation has already been done at Girish Park's Y siding and Maidan's Y siding.

After a gap of 39 years, steel-made third rail is going to be replaced with aluminium ones ensuring an 84 per cent reduction in energy loss.

The Metro Railway plans to introduce 35-km aluminium third rail in this corridor within the next two years.

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