Four fire engines and around 25 firefighters were called to reports of grass alight on Eade Road in Tottenham.
Around 40 metres of riverbank, trees, fencing and undergrowth was destroyed by fire. There were no reports of any injuries.
A London Fire Brigade spokesperson said: “When the ground is extremely dry, grassland and parks will burn quickly when exposed to even the smallest of sparks.
“If you see a grass fire, don't attempt to put it out yourself as grass fires can travel very quickly and change direction without warning. Call the Brigade and let us know where the fire is.”
The Brigade was called at 1608 and the fire was under control by 1732. Fire crews from Tottenham and Hornsey fire stations attended the scene.
The cause of the fire is under investigation.