A local state of emergency is in place for the peninsula following torrential rain that has swamped the settlement of Little River.
NZ Transport Agency Waka Kotahi says floodwaters haven't receded enough for the road to open, while MetService has extended an orange heavy rain warning for the peninsula until 8pm.
Meanwhile, across Banks Peninsula about 260 homes are still without power, and cell phone coverage is out for many people.
About 130 of those properties are around Little River, Okuti Valley, Peraki Bay, Robin Hood Bay and Te Oka Bay.
Orion is warning that many of those homes could be without power until tomorrow.
Telecommunications Forum chief executive Paul Brislen said Two Degrees was now fully operational in the Banks Peninsula area, but One New Zealand and Spark were still off line.
He says people on any network will still be able to reach emergency services using the Two Degrees connection if needed.
The forum has been working with Civil Defence and the Life Lines group on a plan to fix the damaged fibre line.
"We had a meeting earlier on about being able to bring in a Defence Force Unimog or a convoy of four wheel drive vehicles to assess the damage and see about repair," said Brislen.
He said it could take a day or two to restore the cell network.
Brislen said first they needed to find where the break was, and then whether it was one or multiple breaks.
