The cost of running cable cars across the Thames in east London could hit £6million in its first year.
Transport for London has shelled out almost £500,000 each month on the Emirates Air Line since it opened in June 2012.
Passenger numbers on the crossing, between Greenwich Peninsula and the Royal Docks, have fallen by around 80 per cent since the end of the Olympics. In December the cable car was used by around 20,000 passengers a week.
Just 301 people used the service on September 24, when high winds forced it to close for eight hours.
The number of cable car users fell from a peak of 180,804 during the Olympics to 34,885 in a sample taken during the week ending November 4.
The crossing cost £62.7m to build – with TfL still waiting to recoup all of its £15.5m outlay from sponsors Emirates and EU funding.
But a spokesperson for the organisation said the project would be financially neutral in the future.
“It is envisaged that revenue generated will, over time, cover all costs including the operating costs.
“The Emirates Air Line should make a modest surplus in the medium term and any surplus made will be reinvested into the transport network.”
The cable cars’ running costs were released following a freedom of information request.
The figures are likely to reginite criticism over the airline, which has been described as a “tourist attraction” with “pitiful” passenger numbers by leader of the London Assembly’s Liberal Democrat group Caroline Pidgeon.
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