RAIN is thwarting efforts by emergency workers to strengthen a faulty levee bank protecting homes from floodwaters at Wangaratta.
It's feared the levee will collapse and inundate 60 houses and put in danger the lives of those residents who have refused to leave their homes.
State Emergency Service spokesman Lachlan Quick says the levee is a major concern for authorities.
"It's raining there and they can't get in to work on it,'' Mr Quick said.
SES incident controller Keith O'Brien told journalists in Wangaratta that the fault in the levee is being weakened constantly while there is floodwater in the Ovens and Kings rivers.
He said the breach could occur within hours, days or weeks.
"When that breach does occur the water will rush into the area inside the levee and, depending on the depth of water in the river, will jump two to three metres,'' Mr O'Brien said.
He said residents have been told that if the levee breaks there will be assistance but there may be a time delay.
"We won't necessarily know when it breaches - we'll respond as soon as we know but there's no guarantee that someone will be able to get there in time to save lives,'' Mr O'Brien said.
"If the levee breaks, in the first instance the water from the river will rush through the breach very rapidly and anyone close or near that will almost certainly be knocked off their feet with the risk of hitting their head and being drowned, or whatever the case may be.''
The work on the levee is being held up due to rainfall, with up to 50mm of rain expected over the next 24 hours in the northeast.
Townships along the Murray River are preparing for the floodwater, with Echuca the biggest concern.
A community meeting is being held there and residents are sandbagging their properties.
Albury is remaining below minor flood level, Corowa was expecting a peak near four metres early today, resulting in minor rural flooding, with Tocumwal likely to reach moderate flood level of 6.7 metres late today.
At Warracknabeal, water in the weir pools is being released as residents brace for the floodwaters to fill up the Yarriambiack Creek, a tributary of the Wimmera River.
Town mayor Jean Wise says a number of low-lying businesses and homes can expect minor flooding but residents are well prepared.
"We have let a lot of water flow from the creek out of the weir pools to drop the level so we are ready for it,'' Ms Wise told AAP.
"We're estimating the water may reach Warracknabeal by late today or early tomorrow with the peak on Saturday.
"It's going to cause a little bit of flooding but we have taken precautions on that with sandbagging.''
