During a routine flyover on Sept. 7, sheriffs spotted a group of marijuana plants on the northeast quadrant of the state park. Sheriffs also saw suspects running away, said Roland Gaebert, sector superintendent for California state parks.
"We went out there first thing in the morning and cleared the area with rangers and Contra Costa County sheriffs, and no one was caught," Gaebert said. "Between 2,000 and 3,000 mature plants were removed."
State and county officials and rescue volunteers have since destroyed the plants, but the investigation is ongoing. Gaebert said investigators are not sure who was involved or if they are connected to previous growing operations.
"Clearly the message is that there's at least a perceived comfort zone by these folks to grow more and more on public land," he said. "We hope that we can at least contain some of this activity."
This is the second marijuana growing operation to be raided in a local park within the past three months. In July, East Bay Regional Parks police raided an operation in a remote area of Las Trampas Regional Park and confiscated over 3,300 plants worth more than $1 million. Like the Las Trampas grow, suspects at Mount Diablo tapped into the park's natural water system and used spring water to irrigate their plants.
"We have had other grows around Mount Diablo but they were in county jurisdiction," said Jimmy Lee, director of public affairs for the County Sheriff. "I cannot address the question of any increase in marijuana grows in state parks as we do not track that. As far as our cases there has not been any increase."
Although Gaebert could not speculate about trends in marijuana growing operations, he suspects the recent sightings and subsequent busts are a result of the "law of averages."
"There's more successful growing going on than is being discovered. We had a grow last year, there's a grow this year. This is obviously more than we've had in previous years," he said, adding that a longer rainy season might be a reason behind increased growing rates.
While scientists investigate the impact of the operation on Mount Diablo's environment, crews will continue to clean up residue at an unknown cost to the state and county.
"We still have a mess to clean up. There's piping, trash, encampments, food, just a real mess that's going to take quite a cleanup effort," Gaebert said. "We know there's a lot of damage to the natural resources and the extent of that has yet to be determined."