Manawatu Mayor Ian McKelvie says there needs to be significant investment in developing a long-term alternative to the Manawatu Gorge.
A slip has closed State Highway 3 through the gorge since August, forcing vehicles onto the Pahiatua Track and the Saddle Road.
Mr McKelvie says alternative routes are costly for transport companies because of increased fuel costs and wear and tear on vehicles.
He says other roads connected to the Pahiatua Track and the Saddle Road are experiencing traffic volumes they were not designed to handle.
Tararua Mayor Roly Ellis says heavy trucks are damaging the back roads and will now be redirected through Woodville. Chicane barricades are due to go up on Wednesday.
The gorge road is not expected to be cleared for another two months.
Mr Ellis says the Transport Agency is to pay for damage to the smaller roads and he is hoping for funding for more lay-bys and passing lanes on the diversions.
Palmerston North Mayor Jono Naylor says the diversions are adding 15-20 minutes to the journey through the region and it's costing businesses in Woodville $60,000 a day in lost revenue.
