Papakura truck fire: Emergency repairs underway to fix burnt-out section of motorway

A section of Auckland’s Southern Motorway is still under repair after a truck loaded with chemicals exploded into flames.

The truck carrying canisters of flammable gas and other chemicals burst into flames on State Highway 1 near Papakura on Wednesday.

The northbound lanes near Beach Rd Interchange were closed for nearly seven hours due to the fire.

Waka Kotahi NZ Transport Agency Auckland System Management manager Paul Geck said the agency carried out emergency pavement repairs to the road surface on Wednesday night.

Aftermath of the fiery explosion that prompted resident evacuations and motorway closure. Photo / Jack Ferguson

Last night, crews removed the top layer of soil and most debris from the site, he said.

“We are pleased to report none of the spillage entered into any of the waterways off the network. Our crews will be back in the area at a later date to replace the topsoil and barrier.

“There is a very low risk to the public from the spillage unless they have been in direct contact with the debris.”

EnviroWaste had tested for VOC (Volatile Organic Compounds) and hydrocarbons and “these weren’t detected to be at a level where our staff needed a special handling protocol to remove the debris and soils from the site”, the agency said.

Auckland Council GM Licensing and Regulatory Compliance Mervyn Chetty said the council had advised residents who contacted them that rainwater tanks should not be used for drinking water unless properly treated.

“To prevent contaminants that may have fallen on collection surfaces such as rooves and guttering, tanks should be disconnected until the surfaces have been washed down and any contaminants removed.

“Our compliance investigations team on site has checked the local stormwater network and nearby waterways.

“At present, the runoff from the chemical fire is contained to the nearby stormwater rain garden and there is no evidence on site that the chemical runoff has entered the Papakura Channel/Manukau Harbour.”

Te Toka Tumai - Auckland Regional Public Health had said the risk of exposure to smoke was low.

“The fire only burnt for a short time before being extinguished, the smoke plume dissipated reasonably quickly, and many people in nearby areas will have had their windows closed given it was the early hours of the morning.

“For most people symptoms caused by smoke inhalation disappear soon after exposure ends and cause no long-term health problems.”

Firefighters at the scene of the massive truck fire on Auckland's Southern Motorway.

Witnesses to the incident described explosions like “gunfire” and flames as high as 50m, resulting in 15 homes and up to 30 residents being evacuated. The fire was extinguished after an hours-long battle by emergency services.

Mainfreight’s managing director Don Braid said the Chemcouriers truck was carrying cans of aerosol paint from Rotorua to Auckland. The driver escaped unharmed and the cause of the explosion was under investigation.

Papakura resident Steven Shortt said he was woken by several explosions just before 3am, after the truck caught fire in a northbound lane, just north of the Papakura on-ramp - and near his house.

“Some of the explosions were massive. Flying fire projectiles were getting thrown into our front lawn. Cars are covered in ash across the whole front. There were burning embers across our front lawn. It was pretty crazy, man.

“I’ve never in my life seen anything like that before. The whole upstairs of the house is hot against the windows. The explosions you could feel from across the road, the heat and the impact. It was like a war scene.”

Shortt said the rear carriage of the truck was destroyed in about 10 minutes and the rest of the truck about 20 minutes later, amid repeated explosions.

Auckland Regional Public Health said people who were exposed to smoke and were experiencing shortness of breath, wheezing, triggering of asthma symptoms or chest pain were advised to see a doctor immediately or visit an emergency department.

“If you have contact with ash or debris please wear a mask. If you feel unwell after contact with ash or debris please contact your GP, or call Healthline on 0800 611 116.”