Days of heavy rain saw the Manning River surpass the 1929 record of six metres earlier this morning.
The SES warned that residents in Taree, Wingham, and Glenthorne may be isolated by floodwaters for several hours.
In some locations, people have been urged to move to higher ground to make rescues easier.
Evacuation emergency warnings are in place at Manning Point, Coopernook, Buladelah, Gloucester caravan park, Ferndale caravan park, parts of Paterson, and parts of Dungog as of this morning.
But residents in parts of Wingham, Taree, and Dumaresq Island are told it’s too late to leave.
In the 24 hours to shortly before 6am, the SES responded to 892 incidents, including 130 flood rescues, mostly in the Taree, Wingham, and Glenthorne areas.
These rescues included a number of cars that had driven into floodwaters.
Other people had to be rescued from their roofs as water rose into their homes.
“This is a dynamic situation where a number of evacuation warnings were issued through Tuesday and overnight, with residents’ door knocked as well,” SES state duty commander Assistant Commissioner Colin Malone said.
“The NSW SES and our emergency service partners are deploying every available asset to assist with these rescues.”
In one incident overnight, 24 people were rescued from the flooded Pacific Highway at Ghini Ghini.
Major flooding is also underway on the Hastings, Gloucester, Williams, and Paterson rivers.
In pictures: Rising floods cut off towns, rescues underway
More severe weather is expected today, with moderate to heavy rainfall from the Mid North Coast up to Grafton.
Flash flooding is also forecast in higher parts of the Mid North Coast district.
Falls of 150mm to 200mm in 24 hours are possible around Coffs Harbour, Port Macquarie, Taree, Kempsey, Woolgoolga, Sawtell, Dorrigo, Wingham, and Yarrowitch.
