One hundred and thirty kilometres north-west of Melbourne a community is on edge watching water levels rise again.

But this time, instead of floodwater in their streets, Rochester residents are watching the height of Lake Eppalock, a reservoir constructed between Heathcote and Bendigo.

Rochester resident and mother of four Eliza Watson says displaced locals feel like "sitting ducks" as the water volume in the reservoir hits 97 per cent.

She said residents were anxious as the lake, which spilled just eight months ago, was so full.

"I think the very least that could happen is some communication and some reassurance about what's going on and whether they actually have a handle on the situation," she said.

Hundreds of the town's residents are still displaced after their homes flooded in October last year.

"This flood that happened to us last year was catastrophic," Ms Watson says.

"We knew in the weeks leading up to it that we may flood, but the level of flooding was something that no-one anticipated.

"The ongoing trauma of the event … then being out of your home, living in a caravan, the stress of dealing with insurance companies, the stress of dealing with extended family.

An inquiry into last year's major flooding event has launched and will hold public hearings across the state between August and October. 

Calls for water to be released 

Residents are calling on reservoir operator Goulburn Murray Water (GMW) to release more water from Lake Eppalock. 

Rochester resident John Atley said the swelling lake has become a serious cause of anxiety for flood-affected residents.

"There’s no confidence in the town, the government or the shire," Mr Atley said.

"Everyone's too silent. Our town’s just been left."

He said townsfolk have heard nothing from authorities, at a time when residents want reassurance about swelling lakes and rainfall forecasts. 

Mr Atley said another six months was too long for the town to wait for answers.

"No-one's giving us any confidence. Everyone's looking at the rain and we're worried," he said.

"People are not coming back if this happens again."

Not designed for flood mitigation

Lake Eppalock is a fixed crest spillway, which means GMW is unable to release more water than the capacity of the outlet valve, which is 1,600ML a day.

It's currently releasing 150ML a day.

Water Storage Services general manager Martina Cusack said despite being at 97 per cent, the water authority was not able to release more water.

"The water is owned by the entitlement holders and they put their water orders into GMW to release the water. That's what dictates what we release to the valve at this point in time."

Ms Cusack said GMW works closely with the Bureau of Meteorology and State Emergency Service. 

The Bureau of Meteorology's climate outlook forecasts a low chance of between 20 to 30 per cent of exceeding above-median rainfall in July to September in the north-central region. 

"When there is a predicted weather event or rain event that suggests the dam may spill we can increase the flows to reduce the level of spill, but that's the only time we can do that," Ms Cusack said.

Ms Cusack said GMW will look at the recommendations from the independent assessment of Lake Eppalock, but for now it was watching the weather forecast. 

"If there is predicted rainfall that suggests we will start spilling, we will open up the valve to do pre-releases."

The Bureau of Meteorology recently said Australia had its second-driest May since national rainfall records began in 1900.

Reviews underway 

A state government spokesperson said Lake Eppalock and Lake Eildon was being assessed to see if changing operating rules or infrastructure could better protect downstream communities from future flooding.

The findings are expected to be released in November. 

"The minister for water has been clear in her expectations that Goulburn Murray Water regularly and proactively engage with communities and landowners in a range of ways," a spokesperson says. 

The assessment findings are planned to be released in November this year and will feed into the Rochester Flood Management Plan review being completed by Campaspe Council with support from North Central Catchment Management Authority.

The spokesperson says the Rochester Flood Management Plan will be updated with new flood mapping and modelling from the October 2022 data and findings from the Lake Eppalock assessment.

Editor's note 30/06/2023: The story has been amended to remove inaccurate information regarding formal consultation by the state government.