While it's become a staple along the eastern stretch of I-70 in Denver and other commercial and industrial enclaves around town, the stanky, skunky stench of marijuana growing operations isn't beloved by everyone. In fact, back in 2017, the Denver Department of Public Health & Environment adopted requirements to "mitigate and control nuisance odors" of legal marijuana production facilities in Denver as the industry exploded after recreational legalization — but some growers aren't following the rules.
In a memo issued on July 24, the Denver Department of Excise & Licenses notified marijuana industry stakeholders that the DDPHE has "found high rates of non-compliance" regarding local odor control rules. With over 310 medical and recreational marijuana growing operations registered in the City of Denver, licensing officials say the health department isn't playing around this time.
"As a reminder, DDPHE will take enforcement actions when facilities do not meet city standards," the memo warns. "This could include, but is not limited to, an administrative citation and a monetary fine and/or General Violations Summons, which will require your appearance in court."
A handful of rural counties in Colorado allow outdoor farming, but Denver requires marijuana growing to stay indoors. Licensed cultivations in the city must install odor control measures such as carbon filters and HVAC systems to prevent the strong smell of sweet, sticky weed emanating from their buildings. They're also required to use approved odor control equipment, have odor control plans on site, and maintain local complaint and maintenance logs.
Why Is the Smell of Weed So Potent?
Cannabis is on a short list of plants with a large variety of terpenes, or aromatic compounds responsible for a plant's smell and flavor. The more terpenes a cannabis plant has, the stronger and more attractive the smell and flavor will likely be. Quality pot can test out at around 3 to 5 percent in terpene content, but growers are always trying to increase those numbers.It's not just a flavor thing, either. As medical and recreational marijuana use evolves, users have flocked toward certain terpenes for specific effects. Terpenes contribute to the consumer experience and "may also enhance many therapeutic benefits," according to research in Thailand, and they play a large role in a strain's market price.
Growers are successfully breeding plants high in the same terpenes found in hops, fruit, lavender, pine needles, vanilla and garlic, among a long list of other things that aren't cannabis, but the majority of pot still smells like a mixture of gasoline and skunk spray. Myrcene, a common terpene found in hops, mangos and cannabis, can often smell like the organic sulfur mixture skunks produce.
Although myrcene isn't quite as potent as a skunk's booty juice, terpenes are easily detectable by human nostrils. Cannabis terpenes are so strong aromatically that the Colorado Department of Public Health and Environment was worried they could be harmful to the environment, and preliminary CDPHE research found that weed terpenes could be volatile organic compounds that could potentially mix with other volatile gases.
However, a deeper CDPHE study found that that risk is negligible, and that marijuana terpenes are only harmful to taste and sensibilities. According to CDPHE environmental consultant Kaitlin Urso, who led the CDPHE research, a strong aroma with low volatile concentration shows that "our noses are perfectly tuned to smell marijuana."
As the City of Denver is all too aware.
