Amber Norori’s oped on April 19 (“Legalization of marijuana could promote drought alleviation”) contains many fallacies, leading the author to false conclusions.
She writes, “The average cannabis plant needs 6 gallons of water a day and has an average 150-day grow cycle, so for a medium sized grow with about 500 plants, that would be a total of 450,000 gallons for one harvest of one plot. To put this water use into perspective, the amount of water needed to raise cannabis is double the amount of water needed to grow grapes.”
Cal NORML examined the 6 gallons/day figure, which was not measured or calculated by Fish & Wildlife or any other agency, but merely extrapolated to from an early, incomplete estimate. Cal NORML did a study and put the figure at 2.3 gallons/day, but not for the entire 150-day cycle.
The real question, however, is yield. While cannabis, acre for acre, may use more water than grapes (depending on planting density), UNESCO estimates that 26-29 gallons of water are required to produce a glass of wine. By contrast, we estimate that the water needed to produce one joint of marijuana is somewhere between 1/6 and 1/2 gallon. Therefore, if Californians care about the drought they should put their wine aside and light up a joint instead.
Ms. Norori also talks about increased acreage used for marijuana cultivation. But let’s put that into perspective. In 2014, the USDA reports that the total acreage of wine grapes grown in California was 615,000. Our estimates for total acreage used for marijuana is 800-3000, or just 0.05% of the acres used for wine grapes.
As far as total water consumption in the state, alfalfa is the top water-guzzling crop at over 5 million acre-feet used yearly. An estimated 70 percent of alfalfa goes to feed dairy cows and, by one estimate, California is exporting 100 billion gallons of water a year to China yearly in the form of alfalfa hay.
Almonds use about 3.29 million acre feet of California’s water yearly; rice uses 2.8 million, and grapes 2.2 million. Marijuana? About 12,000 acre feet. Yet that crop is to blame for the drought?
There have indeed been localized problems involving marijuana cultivation in streams critical to fish populations. However, again, the wine industry has been much more damaging on a larger scale throughout the state as it has rapidly expanded its acreage used. It’s even legal for vineyards to use extra water to keep their grapes from freezing when needed.
At a state hearing held last year in the California Assembly Joint Committee on Fisheries and Aquaculture, all the water and fishery experts talked about problem regions other than the Emerald Triangle, but all of the law enforcers talked about nothing but that region. John McManus of the Golden Gate Salmon Association said that although there are salmon on the Eel and Klamath rivers, “our bread and butter is from the Sacramento Valley,” which provides for much of the ocean salmon fishing in California and Oregon. The water from that valley is diverted to rice paddies and huge nut and fruit orchards owned by folks like Stewart Resnick with a lot of political clout to keep the flows heading their way while everyone blames poor little pot instead.
Most of the estimated 50,000 marijuana farms in California are quite small, and while Cal NORML is certainly in favor of reasonable and meaningful regulation of commercial cannabis cultivation, let’s be fair about it. Wild accusations like those repeated in your paper are leading to much stricter regulations on marijuana farms than on other crops, and if that continues it will force the market towards large, industrial-sized farms that will cause more damage to the environment and the economy.
Ellen Komp is the deputy director of California National Organization for the Reform of Marijuana Laws.