THIS MONTH should see another 6·5 km of Delhi Metro Line 3 opened from Dwarka to Dwarka Sub City, following the inauguration of the Barakhamba Road - Dwarka section by Prime Minister Dr Manmohan Singh on December 30.

Commending Delhi Metro Rail Corp, Singh said the capital's metro was 'one of the most technologically advanced and safe rail-based mass transit systems in the world'. Preparations are already well in hand for a second phase totalling 50 km which is due to be completed by 2010, when the city will host the Commonwealth Games.

Property and retail development around the metro stations is flourishing, and Delhi's success has encouraged other cities to bring forward their own plans. Singh agreed that other cities needed metros, but remarked that 'each city must evolve its own technically and commercially feasible solution'. DMRC was appointed last year as prime consultant for Kochi, which a plans a 25 km elevated light metro; bids for a 30-year DBOM concession were due by February 28.

Given that Singh included a proviso that central government support would be for 'proven technologies', we are at a loss to explain a sudden enthusiasm for monorails, which are perhaps more notable for a history of bizarre incidents. Last November, for example, two passing trains in Seattle wedged themselves together on a viaduct.

This has not deterred the authorities in Chandigarh, where bids for a 25 km monorail are due by March 22. Kolkata, which is building an 8·5 km extension to its existing 16 km metro line, continues to ponder a monorail, but most ambitious of all is a scheme in Chennai. Bids were due to be submitted to the Tamil Nadu government last month for a 300 km monorail network, to be built on a DBOM basis. Needless to say, the world's largest monorail network is expected to be profitable.