Motorists who got caught up in an effluent spill that resulted in traffic backing up on Auckland's southern motorway are being told to wash their cars.
Untreated waste from a truck spilled across the southbound lanes of the motorway near Takanini about 10.30am on Thursday.
When the fire service got the initial call, it was thought ready mix concrete had been spilled on the road and the fear was it might set before it could be cleaned up.
But when fire crews they arrived at the scene, they discovered something a little nastier.
Hoses were used to clean up the spill and it took close to two hours to wash down the road, a fire service spokesman told NZ Newswire.
The New Zealand Transport Agency says anyone who drove through the spill should wash their cars.
"We'd hate for anyone's vehicle to be damaged by this effluent so our advice would be to use a garden hose to wash the paint and the undercarriage of your vehicle, and be careful not to use your bare hands," acting Auckland highway manager Mieszko Iwaskow said.
Traffic in the area remains heavy.
Meanwhile, there were also delays in the Auckland CBD after a truck crashed on Sale Street.
The road was closed while a clean up was underway.