Thames Water has said the A3 in Kennington will remain closed over the weekend, after the road was flooded on Thursday.
There's been major disruption after a 30 inch pipe burst, which then caused a damage to a smaller pipe.
Engineers are still working to clear debris and to find out what caused the problem.
Thames Water has thanked the London Fire Brigade for helping to pump out gallons of water and for distributing sandbags to protect residents
More top news
Shirley Golbourne, who has dementia, was last seen at around 3pm on Saturday at the Glebe Court residential home on Blackheath Rise.
Surrey Fire and Rescue Service tackled a 20-hectare fire at Thursley Common, which sits on a nature reserve between Thursley and Elstead.
Demonstrators gathered in London after the death of a black man in the US which has seen a police officer charged with third-degree murder.