Water in California is a notoriously hot commodity. As a state that’s spent more time in a drought than out of it during the past five years, legalizing a new, water-intensive agricultural crop—especially when that crop has the historical baggage that cannabis does—is a complicated process.
Done carelessly, cannabis grows can have profoundly negative impacts on nature, polluting waterways with pesticides and clearing trees and shrubs that help support a healthy ecosystem. This is especially true of illegal cultivation, which has bled into national forests and other protected land in recent years.
On the flipside, when done thoughtfully, cannabis uses a lot less water than California’s other agricultural staples, such as almonds, said Hezekiah Allen, executive director of the California Growers Association—and it offers a considerably higher profit margin.
“We’ve got a [water] crisis on our hands in California, and it’s much bigger than cannabis,” Allen said.
In an effort to balance environmental concerns with marijuana’s projected $7 billion market, California is ushering in a bevy of rules and regulations related to water use. In June, Gov. Jerry Brown signed a cannabis omnibus bill that, among other things, sets standards for organic marijuana and establishes environmental protections.
The bill, SB 94, includes a provision that allows regulators to restrict cannabis cultivation if they determine it’s causing environmental harm. Specifically, it bars the Department of Fish and Wildlife “from issuing new cannabis licenses or increasing the total number of plant identifiers within a watershed or area, if the board or the Department of Food and Agriculture finds, based on substantial evidence, that cannabis cultivation is causing significant adverse impacts on the environment in a watershed or other geographic area.”
In other words, the goal is to limit cultivation to only what California’s ecosystems can support.
The clause is similar to one tucked into Proposition 64, which voters passed last year to legalize adult-use marijuana. It requires each individual cannabis plant to display a unique ID number—and it says that if a particular watershed can’t support additional cultivation, no new plant identifiers will be issued.
That means growers won’t be able to plant where there’s not enough water to support their crops—something that could spell disaster for cultivators who rely solely on water from watersheds, said Allen, a former grower who now focuses full-time on public policy.
California currently plays host to roughly 40,000 to 80,000 cannabis growers, according to estimates from both industry groups and the US Drug Enforcement Agency. To stay afloat, cultivators will need to focus on sustainability, Allen said, such as storing rainwater during the wet months for use during the dry summer.
“It’s not going to be, ‘No you can’t grow,’” he said. “It’s going to be, ‘No you can’t grow unless you store enough water.’”
The overarching goal of the legal framework around water use is to require growers to be “good stewards” of water if they want to continue operations unimpeded, said Allen, noting that cannabis can actually be grown on a very small footprint using “barely any water” compared to California’s other primary cash crops. Most cannabis-producing regions in the state, he said, could rely completely on captured rainwater to irrigate.
But while rainwater is free, the equipment to capture and store it can cost a pretty penny. Allen said cultivators need to formulate realistic business plans that fold in the cost of a rain-catchment system. For a in Northern California, that could cost approximately $250,000 to $300,000.
While the wonders of rainfall may work fine for Northern California growers, the approach runs into problems in the arid climes of Southern California. By Allen’s calculations, based on the average amount of water needed per square foot of grow space, a cultivator with a 100-square-foot cultivation area would need to capture 15 inches to 18 inches of rain per year to effectively irrigate. While this past winter was California’s rainiest season in 122 years—with the state, on average, receiving a whopping 27 inches between October 2016 and February 2017—that’s far from the norm. The five seasons prior saw record low rainfall throughout the state, with many Southern California cities getting less than 10 inches per year.
The rules governing water use in cannabis are complex and intertwined. They include statutes born of cannabis laws as well as regulations promulgated by various state agencies. Earlier this month, the State Water Resources Control Board released its 117-page draft cannabis cultivation policy, which aims to ensure that water diversion and waste disposal don’t harm wetlands, water quality, or animal habitats. The rules apply not only to commercial medical and commercial adult-use cultivators, they also govern home growers.
“These are unique requirements for cannabis cultivation, recognizing the impacts that we’re seeing out there in the watershed and where these grows are taking place,” said Erin Ragazzi, assistant deputy director of at the State Water Resources Control Board’s water rights division.
Under the agency’s regulations, cannabis cultivators will be allowed to divert water from streams during the wet, winter months as long as a given waterway’s flow is above a certain level. If water drops below that pre-designated mark, growers will be barred from tapping in.
During the dry season, Ragazzi said, cultivators will be banned from diverting water no matter what the conditions.
“Water supply will always be a concern in the state of California. It’s exacerbated in years when we have lower supplies,” she said.