Transport for London (TfL) are proposing to change the roundabouts at the north and south end of Lambeth Bridge to signalised junctions with traffic lights. This is to improve road safety but it will also provide more space for pedestrians. There will also be restrictions on right and left turns on some roads at each end of the bridge. There are a large number of accidents involving cyclists at these roundabouts.
In addition, they are considering a 20 mph speed limit on the bridge (the ABD have objected to this as unnecessary as no evidence is provided that there is a road safety problem or that it would cut accidents).
The impact on journey times (for both motor traffic and cyclists) seems mixed.
You can see more details, including projections of how the new road layout will look, and respond to a public consultation on the proposals here: https://consultations.tfl.gov.uk/roads/lambeth-bridge/?cid=lambeth-bridge
As usual though with TfL consultations of late, there is no information provided on the cost, or estimates of the cost/benefit analysis.