Maintenance crews in Nanaimo had a dirty job on their hands after someone illegally dumped nearly three-and-a-half tonnes of garbage on a city street.

The trash was dumped in the 3700-block of Shenton Road just after 6:30 a.m. Sunday morning, the City of Nanaimo said in a news release.

A passerby saw the pile of garbage, weighing in at about 3,400 kilograms, and alerted the city.

Pictures of the dump show a heap of garbage bags, some split open, with household trash scattered everywhere.

It took crews equipped with trucks and a front-end loader hours to clean up the mess.

"It appears that the debris had been compacted, as if it had been transported in a commercial garbage truck," said Dave LaBerge, the city's manager of community safety. "This incident not only polluted the neighbourhood, but also posed a risk to blocking storm water drainage and sewer systems."

The city is now asking anyone with information on the illegal dumping to contact police at 250-754-2345 or Crime Stoppers at 1-800-222-8477.