Google is on the nose with the workers and residents of Pyrmont, and it’s got nothing to do with the quality of its products.

A mystery pong has been lingering around the harbourside Sydney suburb for weeks.

Google's new Australian headquarters. Inset: the built-in sewerage processing plant.

The epicentre of the offensive odour appears to be the sewer mining facility connected to Google's new Sydney headquarters, which produces recycled water for toilet flushing and irrigation of the site.

The stench is impossible to avoid for anyone working or living around the Darling Island wharf or Star City casino.