The only significant alteration to the structure of the bridge itself since the addition of the sculptures in 1907 came in 1973, when the Greater London Council (GLC) decided to add an extra traffic lane by reducing the width of the pavements. To counter the increased load of extra traffic, the council announced the replacement of the cast-iron balustrades with low box-girder structures. Despite formal objections from both Lambeth and Westminster Councils, the GLC ignored the objections. In 2015, the extra lane of motor traffic was removed in favour of a kerb-protected two-way cycle track, on the north-east side of the bridge. This forms part of Cycle Superhighway 5.