The fire in Southbridge covered at least 30ha, and the blaze in Springfield was over at least 10ha.
A shed has been wrecked in Southbridge, Fire and Emergency said. Eleven trucks and tankers are responding there, with two helicopters. Police said emergency services responded to Headworks Rd about 3.10pm.
A further 11 trucks and tankers and two helicopters are in Springfield.
In an update, Fire and Emergency New Zealand said the Headworks Rd fire still has multiple helicopters and ground crews working to contain the fire.
Main Rakaia Road is currently closed to traffic from Headworks Rd to Knyvettes Rd.
The Springfield fire is now contained and under control and will be monitored over the coming days.
Fire and Emergency is asking people to check burn piles and not light any fires for the rest of the day.
Raphael Franks is an Auckland-based reporter who covers business, breaking news and local stories from Tāmaki Makaurau. He joined the Herald as a Te Rito cadet in 2022.