Cannabis found in rubbish on NSW roadside

Up to 20 kilograms of cannabis have been found in garbage bags dumped on the side of a road in Sydney's north west.

Police responded to reports that rubbish had been dumped illegally at Brahma Road, North Richmond, on Wednesday morning.

They found up to 20kg of cannabis leaf, parts of a hydroponic growing system and more than 70 bags with parts of cannabis plants.

It's believed the rubbish bags were dumped between 8pm and 11pm on Tuesday.