Trucks moving freight south while Northland train services are suspended as asbestos contamination is sorted out on KiwiRail's Chinese-built locomotives is "not much of a drama" for the main industries affected, says a spokesman.
The 40 DL locomotives do not operate on the Northland line as they are too big for the tunnels.
But with all 40 taken off the tracks when the asbestos problem surfaced last week, trains usually used in Northland are needed elsewhere as KiwiRail adapts its services to cope with the withdrawal of the Chinese-built locomotives.
The DL locomotives are not expected to return to service for at least a week.
Rail moves 274,000 tonnes of freight - forestry, minerals, dairy and other products - between Whangarei and Auckland annually, with trains making two return trips five days a week.