Goulburn Valley Water says odd tasting water is “harmless” after receiving a dozen complaints from Cobram residents in the past week.
Goulburn Valley Water water quality manager Mark Putman said the water - described as having an "earthy" taste and smell - was safe to drink.
While he did not say when the problem would be resolved, he apologised for the inconvenience.
“We know it’s been an inconvenience for people and we’re really sorry – we’ve had water quality specialists and operational teams working round the clock to improve the supply,” he said.
“We appreciate people’s patience and understanding while we work to fix the issue.”
Mr Putman said the earthy taste and smell was caused by a “harmless”, naturally occurring compound called geosmin, which was more of a problem during summer.
“Geosmin can be more prominent during the warmer months due to the presence of seasonal algae in the raw water,” he said.
“This includes rivers and channel systems used to fill our town raw water storages.”
Goulburn Valley Water said some people were more sensitive to geosmin than others.
Mr Putman said treatment plants had increased efforts to treat the water.
“We’ve increased our powdered activated carbon dosing at the water treatment plants to deal with the elevated levels of geosmin,” he said.
“We’re currently seeing the carbon dosing run at unprecedented levels to remove the geosmin.
“We’re also undertaking regular sampling to monitor the water quality and adjust treatment as necessary.”
The water came from the Murray River and has also affected supply in Numurkah, Wunghnu, Strathmerton and Yarroweyah.
The Courier understands taste and smell complaints were first reported on January 9 from Numurkah and Wunghnu residents.