Firefighters were called to the scene of a burst water main on Notting Hill Gate in Notting Hill.
A number of properties were affected by flood water to a depth of around 5ft.
Borough Commander Darren Tulley, who was at the scene, said: "A large water main burst and flooded the basements of a number of properties, both residential and businesses, in the surrounding area.
"We worked closely with partners including Thames Water and TfL to alleviate and divert the flood water.
"Notting Hill Gate was closed between the junctions of Linden Gardens and Kensington Church Street and is likely to remain closed for some time."
The Brigade was called at 0825 and the incident was over for firefighters by 1341. Two fire engines from Kensington and Paddington fire stations, a fire rescue unit from Euston Fire Station and support vehicles were at the scene.