California's ongoing drought has been blamed on a lot of different factors, ranging from climate change to over consumption to the agricultural industry. But here's one more factor that may be draining California dry: marijuana farms. These farms – some legal, most not – soak up a tremendous amount of water in the wilderness. At summer's peak, each plant can soak up about six gallons of water a day, according to a recent report from McClatchy DC. It's so bad in some regions, particularly California's North Coast, that important fish populations are suffering.

Illegal pot farms in Northern California have already been linked to extensive wildlife deaths, as the farms are often protected with rat bait. This has even affected federally protected endangered species. (California banned the sale of rat poison last month to help protect wildlife.)

All of these problems are compounded by the fact that many pot farms are situated, illegally, on public land. "Those are lands that you and I own," Congressman Mike Thompson told McClatchy. "And when people are growing dope there and guarding their operations with guns and the likes, and sometimes with booby traps, we can't use the land that we own. It happens all over."

Other pot farms are apparently being set up in secret on land belonging to traditional farmers. "[Pot] grows hidden in trees on someone else's farm have become more and more common over the past two years," an undercover drug agent told KCRA in February. The National Guard reported that these illegal growers put pumps, dams and irrigation tubing on the sites, diverting water from the farmers' canals. These illegal sites also use pesticides, which end up in the water, sometimes in wells intended for drinking.

None of this is new, of course. Marijuana plots were blamed for diverting hundreds of millions of gallons of water during California's 2009 drought.

The marijuana industry, perhaps not surprisingly, says it is being scapegoated. "It's really easy to point fingers at a very large cash crop that's completely unregulated," Emerald Growers Association founding Chairwoman Kristen Nevedal told McClatchy. "It's one of the main cash crops of the state." Marijuana sales are projected to reach nearly $1 billion in California in 2014.

That number could actually be hard to predict: the California drought is predicted to tighten marijuana supplies and drive up pot prices around the country.

Veteran journalist Dan Rather recently looked into the problem of pot farming in California. You can see the first part of his report in the video below:

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