Pot growers not wasting water

Pro-marijuana activists rally July 28 against a Sacramento County ordinance that subjects pot growers to fines for wasting water.
Pro-marijuana activists rally July 28 against a Sacramento County ordinance that subjects pot growers to fines for wasting water. The Sacramento Bee

Media outlets, including The Sacramento Bee’s editorial board, and public officials, including the Sacramento County Board of Supervisors, have seized upon statements from state Fish and Wildlife officials about marijuana and water use in a few creeks in Northern California to greatly overstate the problem, causing unfair backlash for genuine medical marijuana patients.

California NORML has challenged the figure of 5 to 10 gallons of water per day that’s being used to further vilify cannabis during the drought (“Pot grown outside is a waste of water,” Editorials, July 31).

Fish and Wildlife did not measure or calculate their water usage estimate, but rather lifted it mainly from a 2010 paper from the Humboldt Growers Association. But Humboldt farmers tend to grow extremely large plants, while those eradicated at large, illegal grows are generally much smaller and therefore require only a fraction of the water.

California NORML and Sacramento NORML have surveyed marijuana farmers around the state and discovered that they are using far less water than the Fish and Wildlife estimate, especially when they are able to shorten their growing season. The Mendocino-based Small Farmers Association’s drought management plan calls for goals of a half gallon to 1 gallon per plant per day.

The more pertinent way to look at crops’ water usage is final yield. We calculate an average of 0.72 gallons needed to produce a gram of marijuana, no matter how many plants are grown or how big they are. Since a “joint” is about a half gram, producing one dose of medical marijuana requires less than half a gallon of water.

By comparison, an ounce of beef requires more than 100 gallons of water, a serving of rice around 50 gallons, and a 4-ounce glass of wine between 15 and 29 gallons.

Even using Fish and Wildlife’s figures, marijuana uses a tiny portion of the 35 million to 45 million acre-feet of water used annually by California agriculture. Marijuana, licit and illicit, is estimated to use a mere 3,000 to 15,000 acre-feet of water yearly.

Ironically, counties such as Sacramento that have cultivation bans will be unable to sign up farmers for the Central Valley Water Board’s pilot program regulating water use and discharge, due to be finalized in October. The ultimate answer is better regulation, not more fines and bans.

Ellen Komp is deputy director of California NORML.