Effort afoot to develop water-use rules for pot growers

Faced with an explosion of marijuana gardens, state regulators are developing a new program designed to bring medical cannabis farmers into compliance with state laws governing water use and water quality.

The regulatory program is expected to be unveiled sometime next year, said Erin Mustain, a senior water resources control engineer with the state Water Resources Control Board’s Cannabis Enforcement Unit.

It’s aimed at halting water diversions that can suck dry small streams; unpermitted grading projects that pollute waterways with dirt; and the misuse of toxic pesticides and fertilizers that have been known to poison streams and wildlife.

Water board staff members already have been meeting with medical pot growers in an effort to educate them about responsible water use and farming practices.

“From our outreach efforts and the feedback we have received from the growing community, we anticipate that most cannabis cultivators and landowners will want to work with us,” Mustain said.

Medical marijuana advocates say they welcome the pot permit project.

“Most people do want to comply” with regulations, said Jude Thilman, a member of the Mendocino Medical Marijuana Policy Council.

Those who fail to comply will face the same penalties all water users are subject to when they violate the law. According to the state water board’s website, additional resources will be devoted to investigating and prosecuting cultivation activities that violate water resource and quality regulations.

The permitting program will apply only to legal marijuana growers on private lands. All cultivation on public lands is illegal, Mustain noted. The program does not mean the water agencies have taken a stand on marijuana’s legitimacy, she said.

Regulatory officials have been aware for years that some marijuana growers have been illegally damming and diverting streams and polluting rivers and streams with dirt, trash and toxic chemicals.

But the extent of the massive and largely unregulated marijuana industry’s potential damage to stream flows and fish wasn’t quantified until the release of a state Fish and Wildlife report on North Coast watersheds earlier this year.

The study examined three watersheds in Humboldt County and one in Mendocino County, all of them renowned for marijuana cultivation. They include two near Redway, one near Orick and one that includes Willits.

Using satellite images, researchers determined that an average of 30,000 plants were growing in each of the four watersheds in 2012, an increase since 2009 of 75 percent to 100 percent.

Researchers estimated each plant consumes 6 gallons of water a day, a figure some pot growers say is inflated while others contend it is understated.

At that rate, the plants were siphoning off 180,000 gallons of water daily in each watershed - altogether more than enough to fill 160 Olympic-sized swimming pools over the average 150-day growing cycle for outdoor plants. That’s enough to dry up small seasonal creeks in the region and undo decades of fish restoration efforts, wildlife officials said.

Using the 6-gallon figure, just the illegal marijuana plants confiscated annually in recent years - between 2 million and 4 million - use upward of 1.8 billion gallons over their five-month growing season.

State water officials said they are committed to educating the growers and the public about proper permitting and growing practices.

They ask the public to help educate their cannabis-cultivating friends and neighbors and to report those whose activities threaten to affect water quality, aquatic life and wildlife habitat.

Officials advise those planning to grow to first contact the appropriate regulatory agencies to make sure they are in compliance with state and local laws.

Additional information about the regulatory effort is available at: http://www.waterboards.ca.gov/water_issues/programs/enforcement/cannabis_enforcement.shtml.

You can reach Staff Writer Glenda Anderson at 462-6473 or glenda.anderson@pressdemocrat.com. On Twitter @MendoReporter.