Sheriff Tom Allman of Mendocino County, California, patrols the most fertile marijuana growing region in the world. But these days, thanks to a severe drought that has plagued the state, Allman is fighting the growing problem of water theft by clandestine pot farmers.

“We know in the fall of the year we’re going to be seeing upwards of 5 million gallons of water per day being used for illegal marijuana. Not medical, illegal,” Allman told CBS San Francisco. While the police in the Emerald Triangle are somewhat tolerant of the marijuana grows, the water theft is something they are taking very seriously. “We’re going to arrest you for grand theft. It’s not petty theft. It’s grand theft of natural resources,” Allman said.

The sheriff says he receives about thirty calls a day related to water thefts and emphasizes that his concern is for the citizens affected by this drought. The town of Willits gets its water supply from two rain-fed reservoirs and is one of dozens of California communities that may run out of water in just ninety days. Mayor Holly Madrigal says the water thefts sometimes include people pumping water directly from creeks and streams and that activity has “a really negative impact on our forest lands, on our streams.”

Mendocino County has declared an official water shortage and has passed measures to conserve water. Lake Mendocino near Ukiah is nearly dry and the city has had less than three inches of rain since July, just 12% of its usual rainfall. Gov. Jerry Brown has urged Californians to reduce their water consumption by 20%. Lynn Ingram, a professor at Cal explained that this water year, which began on October 1, “really stands out as one of the worst single years in the last 500 years.”

Sheriff Allman believes the people of his county who would never convict a pot grower are much more likely to convict a water thief. “It’s very hard to find a jury that’s going to convict somebody for growing marijuana. But if we go in front of a jury and say they were growing marijuana but they were stealing water, illegally diverting water, causing environmental degradation, and we know that’s going to have jury appeal and we’re going to get convictions,” he said. Allman reiterates that the issue is really about water, not pot, and his office would go after someone stealing water regardless of the reason.

"Radical" Russ Belville is the host of "The Russ Belville Show."