This had led to five houses at Mangatuna being cut off and residents from three others choosing to evacuate.
The residents from the three evacuated houses are staying with friends and family.
Deputy Civil Defence Officer Nori Parata said others were too late to get out, but they were safe.
Gisborne District Council spokesman Dave Wilson said the region had been hit by a slow-moving weather system that dumped 283mm of rain at Te Puia in the past 24 hours.
A further 80mm-100mm was forecast for the region in the coming day, while about 50mm-80mm had fallen closer to Gisborne city.
The weather system "is just sitting there grinding away giving us the rain we've had, which has become problematic for our catchments", Wilson said.
Recovery efforts in the region were underway and Civil Defence had set up a base at Tolaga Bay Area School.
Wilson said teams were making contact with residents in Tolaga Bay who had chosen to stay in their homes to make sure they were okay.
Teams had also been out since first light checking the city's power and road networks for downed trees and slips.
Multiple slips had taken place on State Highway 35.
Deputy Civil Defence Officer Norrie Parata said the rain had eased over the past couple of hours.
Parata said there had been no reported house damage at this stage, but there was a "considerable amount of slash coming down the river".
Parata believes river levels will start to decrease.
"[We've] got past a peak period for the rivers."
Parata said the rivers hadn't been as high as they were during flooding in 2018.
However, with further rain forecast, Wilson said the teams were "out battling the elements at the moment" trying to make everything safe.
"It is dangerous, which is why we want people to stay at home until we have things under control," he said.
"Now is not the time for people to go sightseeing and look at the damage; we need people to stay at home and let us get on and do our job."
People were especially urged not to travel along SH35 because of multiple slips and surface flooding.
Gisborne City Council spokesperson Diana Dobson said: "SH35 is closed from Tolaga Bay to Ruatoria, and SH2 is down to one lane between Hihiroroa Road (in the north) and Waihuka Road. A temporary speed restriction is in place in the Waioeka Gorge, between Opotiki and Gisborne, due to a slip."
A police spokesperson said: "Police are also attending a number of slips today, on Wharerata Road (Muriwai), Beach Road (Tokomaru Bay) and East Cape Road (Te Araroa). Police is working with other agencies to clear these and reopen the roads as quickly as possible."
Gisborne journey operations manager Donna Mcarthur said: "Please drive safely and do not stop until you have reached your destination."