Odour officers have leaned on technology to track down a bad smell plaguing residents in the Christchurch suburb of Bromley.

Residents reported bad smells through a Smelt-it app on their mobile phones during a March study.

That helped Environment Canterbury pinpoint the odours to the Council's Living Earth organic processing plant and its Ecodrop rubbish station.

Operations director Nadeine Dommisse says the reports were compared with weather conditions and onsite observations.

She says the three data-streams gave them a compelling picture.

"We will now work with other authorities to help reduce odour from the sites.

"Living Earth had already invested in bio filters and misting systems to reduce compost smell."

During the March study residents reported bad odour through a ‘Smelt-it’ mobile app, which was compared with weather and other data at the facilities.