Prepare to isolate alert issued for Gumly Gumly as Murrumbidgee River approaches 9m at Wagga

A watch and act alert advising those in the area to prepare to isolate as the flood peak approaches the low-lying areas, with the roads and access points expected to be inundated or cut off.

"Rising river levels from a flood peak may see low-lying areas in Gumly Gumly being impacted by rising floodwaters over the coming hours," the SES said in an alert issued at 11.20am on Wednesday.

The Murrumbidgee River rose half a metre overnight, hitting the moderate flood level of 9m at 11.30am.

Floodwaters have now spread across large swathes of low-lying land across the city with the river level at its highest since 2012.

In other news:

Gundagai peaked at 9.04 metres early on Tuesday morning, down from a predicted 9.3 metres.

The river is still rising and with up to 45 millimetres of rain set to fall across the region over the next few days, the Bureau of Meteorology has issued a minor to major flood watch for the Wagga catchment.

"We're expecting a very unwelcome rain event," SES public information officer Lachlan Gilchrist said.

"That will continue to impact on inflows, but it should be relatively consistent with the current river levels that we're seeing.

"That being said, everything is so wet right now that the main concern for residents is the potential for some localised road flooding and flash flooding with sudden downpours.

"We again ask people to be very vigilant and cautious on the roads.

"Especially given the condition of the roads after months of rain, any situation where water is over the road, it could be concealing something quite dangerous and we ask people to be very cautious."

On Tuesday afternoon, residents of the following roads in Moorong and Gobbagombalin were given an hours notice to evacuate due to "dangerous floodwaters" of moderate flooding:

People at Wilks Park were later ordered to evacuate by 6pm Tuesday.

"With warnings in place for certain communities, we do ask people to stay abreast of the situation," Mr Gilchrist said.

Those in Gumly and affected by the latest prepare to isolate notice are advised to do the following:

For emergency help in floods and storms, call the NSW State Emergency Service on 132 500. In life threatening situations, call Triple Zero immediately.

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