Three families remain isolated and dozens are without power on the East Coast after days of heavy rain.

Parts of the region have received 300 millimetres of rain since Sunday. Around 120 millimetres has fallen in Gisborne city.

Civil Defence controller Jon Davies says the stranded families have no vehicle access to and from their homes inland from Ruatoria after the high-flowing Mata River damaged the road into the area. Authorities are now considering how to get temporary access to the properties.

Eastland Network is working to restore power to around a hundred homes in the Te Araroa, Waikura Valley and Mata Rd areas.