Brian MacIver
The Western and Southwestern U.S. has been in a “megadrought,” a drought period spanning 20 years or more, since 2000. Using tree ring analysis, researchers from UCLA, Columbia University and NASA’s Goddard Institute for Space Study determined that the period of 2000-2021 was the driest the Western part of the continent has been since the year 800. As dry conditions are expected to continue, this current megadrought is on pace to be the longest such event in the region since the 1500s, according to the same study.
With researchers estimating that 19% of the historically dry regional conditions in 2021 were attributable to man-made climate change impacts, it’s no wonder that local and state regulators have been taking a closer look at agricultural water usage— especially when it comes to oft-maligned cannabis farmers.
“Cannabis is the perfect scapegoat,” says Natalynne DeLapp, executive director of the California-based Humboldt County Growers Alliance (HCGA). “It’s easy to point the finger at it because of prohibition.”
The cannabis industry has been working hard to correct the record—and even some misleading data—about its carbon footprint and resource usage. For example, in a July 2021 proposal issued to county officials, the HGCA, using recent studies and local Water Board data, estimated “total cumulative water use for permitted Humboldt cannabis farms at 884 acre-feet, 33 times less than the water usage for a single large almond farm in the Central Valley.”
However, according to a study conducted by the University of California Division of Agriculture and Natural Resources published in 2019, the amount of water growers said was required in cannabis production was more than twice the amount used for corn, soybean and wheat, and was also more than wine grapes.
While certainly not as water-intensive as large Central Valley almond farms, cannabis growers can have a role to play in the resource efficiency arena, even if their commercial status might shield them from water conservation ordinances.
State of the Southwestern Water Supply
Southwestern North America (a region encompassing California, Wyoming, Utah, Nevada, Arizona, New Mexico, most of Oregon and Idaho, and western Colorado) has been experiencing lower-than-average precipitation and higher temperatures since 2000. The Colorado River Basin, which was dammed to create Lakes Mead and Powell, the main water supply for most of the region, was placed under a Tier 2a restriction order by the U.S. Bureau of Reclamation in August, meaning less water will be released into the reservoirs. This will impact the reservoirs supplying Arizona and Nevada starting January 2023.
The odds of further water restrictions appear likely. If water levels at the Lake Mead reservoir dip below a certain threshold by next August’s 24-month study, it will prompt a Tier 2b restriction, triggering required water savings contributions in California, which has so far been spared from Tier 1 and Tier 2a restrictions.
So far, indoor cannabis growers in metro areas in Nevada and California seem to have been spared from any water restrictions from federal or state officials. David Holmes, founder and CEO of Los Angeles-based Clade9, a cultivation operation and consultancy that also oversees cultivation operations at Las Vegas’ Virtue, says “for indoor growers, water is the least of your concerns” about the cannabis industry given the tight margins, taxes, and competition from the unlicensed market.
“If we can’t get water, we can’t be in business,” he says, noting there is no incentive for regulators to put further hindrances on what has so far been a lucrative crop for state governments. Commercial rates might increase slightly if the water cuts affect the pricing, but “even if you doubled the rate, it wouldn’t kill us, it wouldn’t make a huge impact” given the relatively low commercial water rates, Holmes says.
That’s not to say he hasn’t taken water reclamation into consideration for the operations he oversees. When designing his Los Angeles indoor cultivation facility, he included a water reclamation system as part of a Phase II development. “We’ve designed it, but it’s so expensive [and] it’s a little risky,” Holmes says, given the tight margins for cannabis producers. “Because the city and state isn’t forcing us to do it, we haven’t implemented it.”
Don’t Let Runoff Run Away
One area of water control that authorities are paying closer attention to is water runoff and waste generation. Hours before speaking with CBT in September, Holmes’ facility was visited by the Los Angeles Department of Water & Power (LADWP). The utility service thought it noticed a spike in his facility’s wastewater readings that was accounted for by a timed reverse osmosis (RO) water system intermittently turning off, throwing off the utility’s data readings.
This was the first time the LADWP visited the Clade9 facility, to Holmes’ recollection. “Everything checked out, we were OK—at least on this first round,” he says.
Rob Eddy, technical director for the Resource Innovation Institute (RII), tells CBT that despite so many Western municipalities enacting water restriction ordinances, the regulations that impact agriculture and related industries are water discharge permits.
These legal authorizations, generally granted by local water control boards, allow businesses to discharge specified concentrations and volumes of liquid waste into a body of water over a certain period. Reinforced with the federal Clean Water Act, discharge permits allow local officials to protect their surface water resources from pollutants.
For example, some local jurisdictions might require nitrate and ammonia discharges from facilities working with those compounds to be less than 2 parts per million (ppm), Eddy says, “which is a pretty low amount, considering that most cannabis growers will be growing at … up to 225 ppm, so getting it down to less than 2 is going to require some remediation.”
The cannabis industry, because of its highly regulated nature and adoption of hydroponic growing, has been well-positioned to navigate these regulatory waters. Local municipalities across individual states implemented strict controls on cannabis waste products and often required wastewater management plans as part of their cannabis license application processes. But Eddy says there is still room for improvement, especially for growers using RO systems.
Indoor farmers (and not necessarily cannabis growers) often tout their water efficiency, Eddy says.
“When I see people say, ‘We use a lot less water than field-grown production,’ I always want to know: how much water is going down the drain in your RO unit?” Eddy says. “That’s something that isn’t talked about, the amount of water that gets wasted straight down the drain.”
From the Ground Up
In Humboldt County, Calif., surface water use restrictions are more defined and expand beyond wastewater. Surface water diversion is banned from Oct. 31 through March 31, making it a generally unreliable source for commercial cannabis operators growing year-round. Instead, many of the county’s cannabis farmers pull their supply from groundwater.
Groundwater generally has been uncharted territory, both literally and legally, DeLapp explains.
“If a cannabis operator is attached to a municipal water system, that is regulated by [the local utility],” she says. “If they are reliant on groundwater, they aren’t regulated at all.”
The combination of surface water diversion limits and regulatory carte blanche for groundwater has been a boon for well-drillers, as neighbors drill deeper than one another to solidify their supply, DeLapp says. But the interconnectivity of groundwater systems and surface waters is poorly understood, she continues, and conflicts are bubbling between residential users accusing commercial operators of drying up their wells.
“These conflicts are starting to mount and it’s just a matter of time before … the controversy becomes such a problem that the government has to step in and do something about it,” DeLapp says. “We’re at this early boiling point of what I know is going to be a fundamental change in how not only the state of California, but how the nation, is going to address groundwater.”
The HCGA has been working with the county to promote water storage and lobbying for other regulatory changes.
The organization drafted a report with water-related recommendations, one of which local regulators are already implementing. Because so many Humboldt County cannabis farmers are already fully licensed for cultivation, roughly $10 million of the $18 million earmarked by the state to help county officials transition businesses from provisional to full licenses is being directed toward a water storage program to capture, retain and use rainwater. Grants will help growers offset the cost of new water storage systems, with priority given to growers reliant on groundwater.
“We have the ability to store the majority of our water and not pull any water from either surface water or groundwater during the summer months, and that’s the step the county has proactively taken,” DeLapp says.
She hopes the money will be disbursed soon, as the region’s wet season is rapidly approaching. If Humboldt growers can get systems installed in time, “we will be using less water from groundwater [and] surface waters by next summer, which is really good,” DeLapp says.
Expert Advice
Finding ways to limit water use may become more of a priority for growers in the future.
Drip irrigation, for example, is a must for outdoor farmers, Eddy says. Since the 1980s, irrigation water use in the U.S. has declined despite land use for agriculture increasing dramatically, and Eddy credits drip irrigation for that advancement. “So much of the irrigation in agriculture was done with sprinklers, and they are so inefficient,” he says.
For greenhouse operators or those growing using a medium, Eddy recommends experimenting with container size and substrates with higher water-holding capacity. By using larger containers with high water-holding substrates, growers can reduce water waste “because the pot can hold more and doesn’t need to be watered as often,” he says. That said, there are additional considerations about substrate pH to be factored in, so growers should experiment on a small scale before making a big switch.
Indoor cultivators have the well-known ability to control and monitor nearly all inputs into their crop, and they should take advantage of that, Holmes says. At Clade9's facility, flower rooms are set up in six to eight rows, and each row has its own water sensor providing a reading to his automated system. Once moisture levels drop to a set level, his irrigation system kicks in.
“It’s good to place them in the front of the room because that’s usually the driest plant,” Holmes says. “The ones in the front will typically dry out first because there’s more airflow in the front, they’re not as crowded.”
Holmes also touts the benefits of having a smart irrigation strategy that doesn’t overwater plants. “That’s something you can do without reclamation, something you can do without clearing up your water and reintroducing it,” he says. “As long as you can watch what you’re feeding your plants and not overfeed them, give them the right amount of water they need and not overwater them, you can reduce your water a decent amount.”
