New Zealand Civil Defence Ministry officials in eastern North Island city of Gisborne are keeping a close watch on rising river levels as heavy rain continues across the East Coast.

A total of 200mm of rain fell in 24 hours in some areas north of Tolaga Bay and more than 140mm closer to Gisborne city.

Gisborne Civil Defence controller Jon Davies said, as a precaution, 23 people were evacuated from their homes at Mangatuna, with another 25 leaving their homes voluntarily.

He said a one-meter wall of water roared across rural land at Hexton after a dam burst at the end of Snowsill Road, Radio New Zealand reported.

Several roads on the Gisborne Flats are closed including Harper, Cameron Pilmer and Tucker roads, and Riverside Road in the city.

More than 150mm fell overnight between Ruatoria and Tolaga Bay, causing slips on roads and trees to fall into power lines.

Eastland Network spokesperson Murray Carman said all but a handful of remote houses at the end of a few rural roads have power back on.

Civil Defence said the heavy rain forced some rural schools to close, along with several roads in the Ngatapa Valley south west of Gisborne and the Tauwhareparae road at Tolaga Bay.