By Samantha Lock in Sydney

Days of heavy rain and flooding have taken a toll on NSW roads and its transport network, leaving hundreds of people isolated and as many as 17 homes uninhabitable.

Residents continue to return to their homes northwest of Sydney and along the Hawkesbury River after evacuation orders were lifted following receding floodwaters.

About 800 people were under an evacuation order in the Sydney region where floods damaged more than 60 homes and left 17 uninhabitable.

The numbers are expected to rise.

Evacuation orders for suburbs along the Hawkesbury River were issued on Sunday morning after the river reached its peak of 10.52 metres – about seven metres above average – at 9pm on Saturday.

Flood levels at the Hawkesbury and Nepean rivers reduced to a minor level by 10.30am on Monday with a height of 5.94 metres recorded at North Richmond and 6.92 metres at Windsor.

Water levels normally sit below 4 metres with minor flooding recorded at 4.6 metres.

Premier Chris Minns said the damage could have been a lot worse and thanked emergency services for performing hundreds of flood rescues since downpours began on Friday.

He said there were “no easy answers” for those living in flood-prone regions but reiterated the government’s $200 million commitment for evacuation routes and emergency levees.

But Hawkesbury mayor Sarah McMahon said the mood in the region had turned to anger, criticising government flood mitigation efforts.

Disaster assistance is now available for affected residents and councils across the state.

The NSW State Emergency Service said it responded to eight flood rescues and 585 calls in the past 24 hours – a fraction of the 5000 calls and 200 flood rescues performed since Friday.

Spokesperson Andrew Edmunds said the agency would prioritise welfare checks and assisting with damage assessments throughout the day.

Jemima McDonald, of Thirroul in Wollongong, said she and her partner woke at 5am to neighbours knocking on their door.

“They had to wade up through the backyard … it was a metre and a half high up and they had to get up here and start smashing on our windows to get us to evacuate,” she told ABC Breakfast.

“We were out the door in a couple of minutes with just our son … when we came back about an hour and a bit later, the house was filled with 20cm of water.”

Road and rail disruptions are continuing with parts of the South Coast train line remaining closed due to flood damage.

Bulldozers are set to cut through a temporary evacuation road in the Blue Mountains-Megalong Valley after a land slip shut off the only access road, isolating hundreds of residents.

Blue Mountains mayor Mark Greenhill said cutting a temporary road through rock would take three days and would be contingent on careful geotechnical advice.

Food and fuel drops via helicoper are underway.

Sydney’s Warragamba Dam continued to spill at a rate of 19GL at 11am on Monday, down significantly from 225GL at its peak on Saturday.

The total volume of the spill was 260 GL as at 7am Monday, equivalent to half the volume of Sydney Harbour, Water NSW said.

The Bureau of Meteorology said the worst of the weather has passed, with no thunderstorms forecast for Monday.