The amount came out of a Rapid Damage Assessment (RDA) of the region's roads, conducted by Shoalhaven council engineers and road crews.

And the bill could be even bigger after this week's bout of bad weather.

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Record-breaking rainfall across the Shoalhaven caused more than 160 landslips, with 250 kilometres of roads damaged, according to the RDA.

Shoalhaven Mayor Amanda Findley said the extensive road damage is "beyond imagination" compared to other previous disasters.

"No one really knew what amount to expect, although there was a number of big items that we knew would be on the list, particularly thinking about the landslip at Wattamolla Road," Cr Findley.

"Until this really wet season passes, permanent fixes are going to be difficult to achieve."

At this stage, a summary of the known damages include:

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Cr Findley said Thursday's heavy rainfall caused another blow to communities impacted by road damage, after trees came down at Moss Vale Road.

"It was a big blow to the community of kangaroo Valley having the main road to moss Vale knocked out," Cr Findley said.

"That's been having a really heavy impact on the businesses and community.

"Earlier this week in Milton Ulladulla, people weren't able to get their kids to school because it was too dangerous. It was partly due to conditions, but mostly due to the roads."

Council has received $1 million in financial assistance which has been funnelled directly into road repairs, Cr Findley said, and more is expected to come from disaster payments.

"Right now, we need as much some financial support as we can get our hands on to get this work done as quickly as possible, and return things to as normal as possible," Cr Findley said.

"Because we've been a declared disaster zone, we will be able to make further claims to other levels of government to give some financial support to Shoalhaven."

Meantime, Cr Findley wants to see the federal government direct their focus towards climate action to prepare the region for future disasters.

"Shoalhaven and other councils have been calling on the federal government to put more money into preparedness," Cr Findley said.

"There doesn't seem to be any action coming out of the federal government in any sort of fast way."

A Transport for NSW spokesperson added crews and contractors are continuing to work around the clock to carry out repairs on Cambewarra Mountain, but wet weather may disrupt progress.

"Due to the continued wet weather, we expect there could be disruptions at times as we prioritise the safety of crews and road users," they said.

"Cambewarra Mountain was closed temporarily on Thursday due to fallen trees and debris.

"Crews cleared the road as a priority and were able to safely resume hourly escorts in the afternoon."

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