Waka Kotahi NZ Transport Agency yesterday said it hopes to have a temporary fix in place by April 13 for the Maungahauini Bridge, to restore the vital Coast link.
More than 40 local roads are closed also due to slips and flooding.
Niwa said the heavy rainfall in the region earlier this week set a record with 103 millimetres of rain falling between 4am and 5am at Maungatapere near Whangārei on Monday. That was a new hourly record for a low-elevation station, Niwa said.
"For 103mm to fall in one hour, that's exceptional - you're getting more than what would fall in a month in one hour," Niwa meteorologist Chris Brandalino said.
Gisborne Civil Defence controller Dave Wilson said the ground is so soaked that parts are still moving and people should be cautious.
"The concern for us with slips is that there are a number that are still coming down, and you think well we're trying to work on them. The other issue for us is that any land's that's precarious, a little bit more rain may be the thing that tips it over the edge.
"There are a number of residences that we have got a close eye on, we're working with those residents."
He urged anyone who is isolated by flooding in Gisborne to get in contact if they need help saying it is available to anyone who requires it.
Wilson said people should stay away from all the closed roads.
A long list on the Gisborne District Council website shows numerous roads closures due to flooding, slips, downed trees and washouts.
Some are open only to four-wheel drive vehicles.
Wilson said if there is a sign saying a road is closed, it is for good reason, and no one should be just be going for a look.
More rain is expected throughout this morning.
