A new tool at Porirua’s Spicer Landfill is aiming to put an end to the foul odours that have plagued nearby neighbourhoods for years.
The Porirua City Council recently introduced a seven-metre tall air dispersal fan, originally designed to prevent frost on orchards, to tackle the landfill’s notorious smell. The powerful fan, acquired in November, can be towed around the site and unleashed when conditions are right to disperse odorous air before it drifts downhill to Tawa.
According to council waste manager David Down, the fan is “immensely powerful,” with a blast so strong that people struggle to stand in its path. “The idea is to blast everything around. Everything about this makes sense, so let’s try it and see what happens,” he said.
The smell issue is largely caused by katabatic winds, a phenomenon where cool air flows downhill in the evening, carrying landfill odours into low-lying areas of Tawa. The fan aims to prevent the formation of these layers of foul-smelling air by mixing them with the surrounding atmosphere before they have a chance to settle.
The fan is the latest in a series of measures the council has implemented to control odours at the landfill. Other tactics include extra cover on the tip face and the use of odour-neutralising cannons.
While the landfill’s new tool is promising, Down noted that there’s still some trial and error involved in its operation. Staff are figuring out the best direction, location, and conditions for the fan’s use. In the future, the council hopes to connect the fan to the landfill’s weather stations, which could automatically alert staff to switch it on when the wind conditions pose a risk.
Odour complaints from Tawa residents have been a persistent issue. Although the number of complaints dipped last year, the council had still received 397 complaints by the end of August. The worst months were January, March, and May, with residents describing the smell as either like a “rubbish bin” or “rotten eggs.”
The smell problem has caused delays in the council’s plans to extend the landfill’s resource consent beyond 2030. According to a report by Tonkin & Taylor released in late November, the council has been advised to seek a short extension to 2035, giving them time to explore waste management partnerships with neighbouring councils.
For now, residents are hopeful that the new fan might finally bring relief from the landfill’s bad smell, and the council is optimistic that they’re on the right track.