A Wealdstone street was submerged in 1.5 metres of water from a burst water main on Tuesday (October 24).
Emergency services were called to Cecil Road at 10.55am and evacuated more than 100 people from their homes and businesses as the street filled with water.
Five fire engines and around 30 firefighters and officers attended the scene in Cecil Road.
The water was confirmed to be receding at around 2pm.
A London Fire Brigade (LFB) spokesperson said: "A burst water main has caused flooding to a depth of approximately 1.5 metres.
"The water main has been isolated and the water is receding. Local road closures are in place.
"Over 100 office staff and three residents from a block of flats have been evacuated as a precaution.
“The Brigade was called at 10.55am. Fire crews from Harrow, Stanmore, Northolt and Ruislip fire stations are at the scene."
Streets around Cecil Road remain closed and LFB has advised people to avoid the area.
Affinity Water is working to fix the burst water main.
A spokesman said at 2.30pm: “Our repair team are on site with the fire brigade working to pump out water as quickly as possible in order to be able to start work to fix the damaged water main.
“We will provide an update and estimate on when this work should be completed as soon as one becomes available.
“We are sorry for the disruption to your supply and thank you for your patience.”
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