About 100 holiday cabins were being lifted by crane out to higher ground from their waterfront sites, while paddle steamer operators were raising their moorings in preparation for the deluge.

The river is expected to rise by almost five metres by Wednesday, with heavy gushes expected to hit the waterway at the weekend.

Murray River Paddle Steamers owner Vern Beasley said while planning had been difficult, he was confident it would be business as usual.

''There's a certain resilience out here in the bush. As long as there is no loss of life, that resilience will continue,'' he said.

Mr Beasley said the Murray had risen about three metres at the Port of Echuca in the past three days. Intermittent showers had forced him to move his pile of Murray River red gum firewood to sheds two kilometres from the port to keep the paddle steamer fuel dry.

Across the river at Moama's Maiden's Inn Holiday Park, holidaymakers were shifting their portable cabins from the expected flood path to a neighbouring paddock.

But cabin owner Kerri McDonald, of Diamond Creek, was still wary of the clean-up bill. She said her insurance might not cover her if she stayed put because it would not be flash flooding.

''And the insurance may not cover us if we move the cabin outside the park, so what do you do?'' she said. ''At least it has created a sense of community spirit.''

Another cabin owner, Jackie McDonald, said she had holidayed at the park for years but had not met many of her fellow campers until this week.

Park manager Bob Martin said the State Emergency Service warned him about the river rise on Tuesday and he passed on the information to cabin owners.

''They're all individually owned, so it's their decision if they stay or go,'' he said.

''A few have jacked themselves up and chained themselves down, planning to stay, but many have moved.''

Mr Martin said the park had shifted about 25 cabins a day since the warning.

The SES predicted the flooding at Echuca to be moderate.

While some residents were making their own preparations, others criticised the warning.

Brownz Courtyard Cafe assistant manager Laura O'Neill said she had seen up to 15 caravans leaving town yesterday morning, drying up her customers.

''Normally here at lunchtime we would have between 20 and 30 people, but this morning we have only had a handful,'' she said.

''That could be a loss of several thousand dollars over the next few days if people continue to leave.''