Living with a stink? Technology might help

Milpitas, a city in California's Silicon Valley, has long suffered from an unusual problem: unpleasant odors emanating from industrial sites. One resident, Chia-Ling Kong, couldn't even open her window for over a decade due to the stench from a nearby landfill. While recent improvements have been made, residents still experience several hours of bad smells daily.

In response, local authorities have mandated the use of drones and monitors to track and measure the chemicals responsible for these odors. Kong remains optimistic that a data-driven approach will help pinpoint issues as they arise.

The issue of industrial odors is not unique to Milpitas. Communities worldwide are grappling with the problem, as regulations often fall short in regulating environmental smells. In the US, the EPA does not consider odors a pollutant, leaving states and local governments to address the issue. Urban sprawl has exacerbated the problem, as communities encroach upon previously distant stinky facilities. This trend is a global phenomenon, driven by rising land values and urbanization.

Various technologies exist to combat industrial odors, generally falling into three categories: absorption, chemical conversion, or combustion. The most effective methods can remove 90% or more of the compounds responsible for odors. However, these solutions can be costly, and many operators prefer cheaper alternatives, such as spraying deodorizers over landfills or sewage processing sites. Odor experts are skeptical about the effectiveness of these masking techniques, comparing them to fabric softeners.

Landfill odors present a particularly challenging issue due to the large surface area involved. In Des Moines, Iowa, the city has spent $240,000 annually on odor monitoring technology to identify the sources of odors, which can affect up to 100,000 people in a 10-mile radius. By deploying a network of monitors and weather stations, officials can pinpoint the exact facilities responsible for the stench, eliminating the common practice of relying on human noses to identify the culprit.

Some of the sites blamed for odor complaints in Des Moines have invested millions in upgrading their odor control systems, but companies like Smithfield Foods deny responsibility for the complaints. The subjective nature of odors remains a challenge, as people's sensitivity to smells varies greatly.