The Morton fire, effectively a new front of a massive 400,000-hectare fireground stretching from Batemans Bay to the Southern Highlands, jumped the Shoalhaven River on Saturday evening.

Local mayor Duncan Gair said there were unconfirmed reports houses and structures were lost in Wingello and more at Bundanoon and Penrose.

“It’s a gruelling day going through the affected areas,” the Wingecarribee Shire Council mayor told AAP on Sunday.

“But we have lost houses. There’s no two ways around it.”

Mr Gair, who lives at nearby Fitzroy Falls, said the speed of the fire was so quick he originally thought an emergency warning on the Rural Fire Service website was a mistake.

“It caught me totally off guard,” he said.

Then the southerly change – described as “very aggressive” by NSW RFS boss Shane Fitzsimmons – came through and pushed the blaze towards Exeter and Bundanoon.

Green and general waste at the Moss Vale Resource Recovery Centre, which handles waste and recycling services, caught alight while animals from the nearby shelter were evacuated.

No infrastructure in the RRC was damaged, though green waste collections won’t occur for at least three days.

Moss Vale and Exeter residents were asked to limit their water usage on Sunday evening as water was re-routed to Bundanoon to help firefighting crews.

“Discoloured water is unavoidable and is the result of extra water being pumped through the water system for fire-fighting purposes,” the council said on Sunday.

The fire threat eased on Sunday evening but a watch-and-act alert remained in place.

Communities were urged to be alert to embers, spot fires and falling trees and branches.

Originally published as Homes lost as NSW fire jumps major river