Three sections of State Highway 25 will stay shut overnight, as the eastern Coromandel Peninsula is doused by heavy rain.
Civil Defence is urging people not to drive anywhere in the region overnight.
The community of Hikuai near Pauanui was completely cut off for some time this afternoon.
Resident Bill Prescott helped several carloads of stranded travellers to escape in a surf life-saving rescue boat, which took them down the Tairua River to Pauanui to spend the night.
Prescott said the worst of the weather appears to be over, but it is still raining heavily with strong winds.
He said there are cows stuck on farmland islands as the floodwater slowly drains.
Civil Defence controller Gary Towler is expecting rain and wind will continue until at least midnight.
"The entire Coromandel is getting battered and everyone needs to heed the warnings, stay off the roads and sit this out until tomorrow," Towler said.
Fire and Emergency NZ has attended 16 callouts on the Coromandel so far today mainly for trees down and roof damage and two accidents.
There are 13 people staying another night at the Pinnacles Hut. They will be escorted down tomorrow when the weather clears and the road opens.
The Kauraeranga spillway at SH25 in Thames has held during this afternoon's high tide.
Niwa said a "stubborn swirl sitting in the Tasman Sea hasn't budged in the last three days".