The current service operates every 30 minutes in each direction between London Victoria and London Bridge [via Peckham Rye], and it is operated by two-car trains through most of the day, with four-car trains provided in the morning peak period. It provides the only service for Wandsworth Road and Clapham High Street stations, with all other stations on the line being served by other train services. These services on the South London line, although busy in peak periods, do not have a material crowding problem. Indeed, the latest "passenger in excess of capacity" figures for autumn 2008 show fewer passengers than overall capacity on all trains.
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The reason for the diversion of the South London line between Peckham Rye and London Bridge is that that line carries the smallest number of passengers into London Bridge of all the services into London Bridge. Typically in the morning peak period, some 350 people are on each of the South London line trains arriving at London Bridge between 8 am and 9 am. The evening peak loadings are significantly lower than that.

The original plan, as consulted on by Network Rail as part of the South London route utilisation strategy?or RUS?document, was to divert the South London line service away from London Bridge. That would have created a new Victoria to Bellingham service south of Catford, where sidings exist to allow trains on that service to terminate.
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The south London route utilisation strategy highlighted the potential benefits that the extension of the East London line to Clapham Junction would bring to this area of south London in providing new orbital links to and from south, west, east, north and north-east London and reducing passenger congestion on London Bridge while rebuilding works were under way. However, despite a significant increase in the budget made available to them in recent years, TfL and the Mayor did not believe that the ?75 million scheme was affordable within the TfL budget.
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The Department recognised that the East London line would deliver some additional benefits to passengers, and therefore accepted the responsibility to [extra funding]. TfL therefore proposed to fill the funding gap by withdrawing the replacement South London line service to Bellingham in its entirety from late 2012, with the money saved being diverted towards the capital costs of the East London line extension.