Six fire engines and around 40 firefighters were called to a flooding on Church Lane in Hornsey.
Four flats were flooded to a depth of around 150 millimetres after two water mains burst. There were no reports of any injuries.
Deputy Assistant Commissioner, Lee Drawbridge, said: “Crews worked incredibly hard to divert water away from properties using flood barriers and sandbags, whilst working with partners at Thames Water to isolate the water mains involved.
“Road closures were in place whilst crews worked to make the scene safe. The water was diverted into the main drains and the river, but there may be some continued local disruption to water supplies.”
The Brigade was called at 0045 and the incident was over for firefighters by 0706. Fire crews from Hornsey, Tottenham, Holloway and surrounding fire stations attended the scene.