A grass and shrub fire broke out under the busy Chesterhope Bridge on Pakowhai Rd just before 11am.
Smoke could be seen coming up the sides of the bridge while the fire burned underneath.
The fire was caused by a fault in an electrical cable under the bridge, a fire service spokesman said.
It took roughly five minutes to extinguish, but it was fortunate the conditions were favourable, a fire service spokesman said.
"It was good it wasn't windy otherwise it could've spread a lot further as it's fairly dry around here".