Industrial business is causing a stink in Canterbury, and Woolston is at the centre of it all.
Environment Canterbury has received more than 3000 odour complaints Canterbury-wide since May 2010, 1722 of which were from Christchurch.
While Woolston was responsible for many (533) odour complaints in Canterbury, it was not the only offender.
Stinky suburbs included Belfast, Bromley, Halswell, Hornby and Phillipstown - all of which had a "notable" number of complaints in the last three years.
About 600 complaints had been verified by ECan, resulting in 30 verbal warnings, 15 abatement notices, and 10 infringement notices with fines.
More than 500 complaints have been made to ECan about businesses in Woolston since May 2010. Over the years, alleged offenders have included Gelita gelatine factory, Chemwaste, Independent Fisheries (now closed) and Haydn Brush Co.
Some cases remained open, including the case of a mystery smell in Woolston.
ECan has received 15 complaints about the smell, but has not yet found the source. It now has an officer stationed close by in the hope a quick response would yield results.
ECan sent officers to independently verify odour complaints from the public across Canterbury. If deemed offensive or objectionable under the ECan assessment framework, the complaint was recorded as "substantiated".
Bromley was also a source of ongoing odour problems. More than 200 complaints were made about businesses in the area with 64 substantiated by ECan. Living Earth compost in Metro Place gathered 153 of those complaints, 47 of which were substantiated.
Chief executive Craig Tucker said Living Earth's council-owned facility had been severely damaged in the earthquakes. The company had worked with the community and ECan to minimise impact on its neighbours during a post-quake facility rebuild.
"We work tirelessly to be a good neighbour to our Bromley community," he said.
In Hornby, top alleged odour offenders included Ravensdown fertilisers and Tegel Chicken. Both had large processing plants in Hornby and they generated 76 and 39 complaints respectively.
Ravensdown works manager Peter Hay said the company's 2010 air quality consent was "much stricter" than the previous one. The plant had invested in bio-filters to remove the "rotten egg" smell associated with hydrogen sulphide.
"Ravensdown is a large 14-hectare site that has been here since 1922," Hay said. "At times we are an obvious target of locals who perhaps mistakenly think the odour emanates from the site."
Hay said the company took residents' views into consideration and kept communication lines open.
ECan said an education and advocacy approach was preferred in the first instance to help businesses remedy their odour problems. ECan said businesses complained about in the last three years may have since rectified the issue.
Many complaints were often related to the same incident.
A Haydn Brush Co spokeswoman said the complaints against the company dated back to just after the earthquakes and were from one person. The company had taken the complaints "very seriously". It had resolved the problem quickly and had not received any complaints since.
Gelita told The Press in January that it would take time to implement successful measures to control odours, but it was a priority.
Of the worst smelling suburbs in Christchurch, most were zoned Business 5 - general industrial. According to the Christchurch City Council District Plan, B5 zones had heavy and light industry, warehousing, and processing operations. Compared to other city zones, B5 often had significant noise, traffic and emissions.
B5 zones in Christchurch included Woolston, Hornby, Middleton, Sockburn, Bromley, Belfast and Papanui, many of which included pockets of residential areas.
Most were buffered from condensed residential zones by Business 4 areas - a light industrial area with mixed use.
However when it comes to smells and fumes emissions, wind patterns could render B4 buffer zones obsolete as offensive odours were carried to nearby residential areas.
Industrial zones are up for discussion in 2014 as part of a three-year city council District Plan Review.
Tegel Chicken and Chemwaste did not respond to questions in time before this article went to print.
- The Press
Should park land be turned into carparking for Jellie Park?Related story: Car park plan shows 'breathtaking arrogance'