MORE than 1000 evacuees will return home over the next few days as floodwaters recede across NSW while 23,000 people remain isolated.

No further evacuations were ordered overnight and the SES has shifted its focus to resupplying isolated communities like Yamba and Iluka at the mouth of the Clarence River with food and medicine, an SES spokesman said.

"We'll be using helicopters and flood boats just to get in some essentials," he said.

About 800 residents from Cowper and Bushgrove, located on the Clarence River between Grafton and Maclean, are still under evacuation orders but the SES is hopeful they will be able to return home over the few days.

"There will need to be some assessments made once the water levels drop just to make sure it's safe for them to return," the SES spokesman said.

The SES expects to give the all clear for most people, however some may have to wait up to a week before it's safe to go home.

More than 4000 calls for assistance were received by the SES since the deluge brought by ex-tropical cyclone Oswald began.

But as the danger from the flooding passes, the SES has mainly be fielding requests for resupply.

Yesterday about 50 calls asking for supply drops were received.

About 5800 homes and businesses across NSW spent last night in the dark, but power is slowly being reconnected, the SES spokesman said.