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Motorists had been allowed to use the main road between Christchurch and the West Coast when it snows as long as they could fit chains.
But that has changed this winter.
The passes would instead be closed while graders clear the snow and laid down grit, with vehicles only allowed back once it was safe, NZTA said.
It says this will prevent motorists getting stuck and their rescue causing further delays.
An NZTA spokeman said motorists should still carry chains, and if the road remained closed for several hours, road crews would use their discretion about who they let through.
“Waka Kotahi (NZTA) continuously reviews all its highway maintenance processes and this proposed change is no exception” he said.
“We are bringing these alpine passes into line with the open/closed management regime used on SH7 Lewis Pass and Rahu Saddle near Reefton.
“Given the success we have had managing the Lewis Pass using this approach, in place since 2017, we wanted to extend the same system to the Arthur’s and Porter’s Passes for everyone’s benefit.
“It is simpler and safer for both road crews and road users in terms of fewer delays and less diversions caused by drivers getting stuck in snow drifts or sliding on ice."