Whanganui District Council says reported illegal dumping has been dropping in recent times but it still needs the public to keep it informed.

A Whanganui resident discovered a particularly large pile of dumped rubbish at the North Mole yesterday morning, which he said was a regular occurrence at that spot.

A council spokesman said any reported rubbish dumping would be collected and the council would attempt to find those responsible who could be taken to court if sufficient evidence was available.

"We want to remind people who see others dumping rubbish to take down any relevant details such as number plates so we can follow up."