Thomas Mackley, 20, appeared in Horsham Magistrates' Court on Monday, where he pleaded guilty to littering.

A co-accused Horsham woman, 23, failed to appear in court and a warrant was issued for her arrest.

The court heard that on January 1 at 8pm, a member of the public located several yellow garbage bags floating in the Wimmera River.

Inside the bags were a number of bills containing the names of people from a Creek Crescent address.

Horsham Rural City Council and the Environment Protection Authority subsequently launched an investigation.

Council local laws officers recovered seven bags of rubbish from the water.

The bags were thrown from the Riverside Road bridge, north-east of Horsham, some time during the Christmas and New Year period.

Mackley told the court that he had only dumped one bag out of the seven.

Magistrate Peter Dunn said it didn't matter if it was one bag or more - he was still guilty.

"Don't they have rubbish collection in Horsham? Or public bins? Or a waste management station?" he said.

"These bags were thrown in the river some distance out of town - what is the point?

"Why not put it in your own bin? Or in your neighbours' bin when they aren't looking?

"Why use your own petrol and drive out of town to do this?"

Prosecutor Lauren Coman argued that it was an aggravated offence.

She said the dumping was a danger to the waterways.

Ms Coman told the court that the seven bags contained a "considerable amount of waste", which was mostly glass bottles.

Mackley said he was sorry and that he would not do it again.

Mr Dunn said Mackley had only narrowly avoided jail time.

"It's your lucky day because the council said I should give you a fine, making it hard for me to then put you in jail," he said.

"You're a disgrace."

Mackley was fined $3000 and ordered to pay clean-up costs.

Council development services director Angela Murphy said the river was a problem area for dumping and offenders often targeted isolated areas with vehicle access.

"Dump sites often include construction and demolition waste, hazardous materials such as asbestos and household rubbish," she said.

"The financial cost of cleaning up the dumped rubbish ultimately falls on the ratepayer.

"Council encourages people to report any dumping sites they find," she said.

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