The Coromandel Peninsula town of Whitiangi was cut off by flooding caused by heavy rain this morning.
The New Zealand Transport Agency said that State Highway 25 was closed north and south of the town, making it "effectively cut off on both sides".
In an update at 9.30am, it said both stretches of road were down to one lane but had re-opened.
Drivers have been asked to take extra care and drive to the conditions.
All roads into Whiti are now open, but only one lane. It's still pretty wet and grotty, so #DriveLikeANana— Waikato CivilDefence (@CivilDefenceWKT) March 16, 2016
There have been reports of a slip at Kuaotunu Hill and surface flooding at Simpsons Beach.
About 100mm of rain has fallen since 6am and MetService was predicting more localised downpours throughout the day.
Thunderstorms were possible and the rain might continue until Friday, it said.
Here's a photo taken this morning by Laurna White. Surface flooding at Simpsons Beach just north of Whitianga. pic.twitter.com/jM9YHJ5G25— Scott Simpson (@ScottSimpsonMP) March 16, 2016
So if Whitianga was flooded at Wade Rd & Wharekaho at low tide, that must have been a shit load of rain! pic.twitter.com/o9fgujzHKZ— Melanie D. (@melulater) March 16, 2016
Update: SH25 25 NORTH & SOUTH of Whitianga are now both OPEN with Stop/Go's in place. Take extra care in area & drive to the conditions ^LC— NZTA Waikato/BoP (@NZTAWaiBoP) March 16, 2016