Main roads in Northland remain closed to heavy vehicles today.
A large washout on State Highway 1 south of Kawakawa following the storm and flooding last week has closed the stretch of road.
Mangakahia Road from Kaikohe to Whangarei has been closed to heavy vehicles on advice from engineers to Civil Defence.
The detour remains open to light vehicles.
Civil Defence Controller Alastair Wells said in a statement that the Far North District Council was obliged to close the 25km section of road because the road was at risk of slips.
"The road has been steadily deteriorating while it has been carrying virtually all heavy traffic movements in and out of the Far North since State Highway 1 was closed by a slip near Kawakawa," Mr Wells said.
"The engineering advice we have been given is that there is a serious risk of further slips on our section of the road if we do not close it to heavy trucks immediately.
"There is already one slip below the road which has reduced the useable area to a single lane."
Ruapekapeka Road had been considered as an alternative, but because it was also breaking up badly, there were no other viable options available to accommodate heavy traffic.
SH12 is the only other route for trucks to take to the Far North.
"This is really going to inconvenience the heavy transport industry servicing the Far North, and we apologise that this has been deemed necessary because of safety concerns," Mr Wells said.
He said he understood SH1 would have one lane open by the end of the week.
