Questions raised about cannabis growers’ water use

Associated Press

BEND, Ore. — Charles Cook and Suezan Hill-Cook didn’t think much of a medical marijuana growing operation when it set up shop next to their home near Redmond in 2015. Over the next few years, however, they and other neighbors grew increasingly frustrated with the noise, smells and traffic that come with a cannabis operation.

Then, during the hottest part of last summer, the well the couple relies on for water went dry, and they had to drill a new one. They blamed the marijuana growing operation.

“That was the last straw,” Hill-Cook said, The Bulletin reported Friday.

State and federal research does not link drops in the water level to cannabis-growing operations. While everyone agrees that groundwater levels are declining in parts of the county, the research shows recent declines are part of a larger trend.

Still, the couple’s claim is far from unique in Deschutes County. In areas of the county where cannabis operations have sprung up, anecdotal reports of wells running dry have followed. While a state investigation determined that growing operations had a relatively limited effect on groundwater near Tumalo, that hasn’t stopped rural Deschutes County residents from drawing a connection between uses.

After recreational cannabis was legalized in November 2014, subsequent legislation defined it as a farm crop, to be protected under Oregon’s Right to Farm laws and subject to Oregon’s agricultural water quality rules.

Deschutes County code requires a business looking to grow marijuana to provide a water right permit, a statement that water is available from a public or private water provider, or proof from the Oregon Water Resources Department that the property does not require a water right.

Some growers hoping to break into the recreational market eschew traditional irrigation water, which is typically available only from April to October. Instead, some growers have secured rights to use groundwater to grow cannabis year-round.

In 2017, Bill Tye, a longtime Alfalfa resident with a background in water management, began looking into the impacts stemming from cannabis operations in response to one proposed near his home. He found that between 2015 and 2017 seven domestic wells in his region had to be re-drilled and deepened. Tye, who died in January, included the findings in written testimony opposing the proposed cannabis operation.

A 2013 study from the U.S. Geological Survey concluded that parts of the Deschutes Basin saw water level declines of up to 14 feet between the mid-1990s and mid-2000s, years before recreational marijuana was legalized.

In response to concerns expressed by the Deschutes County Commission, the Oregon Water Resources Department investigated 11 marijuana growers near Tumalo during the summer of 2018. Central Oregon Watermaster Jeremy Giffin, who conducted the investigation, concluded the handful of growing operations that had gotten up and running in the area had a very small impact on the overall decline in groundwater levels.

“At the end of day, we were surprised at how little water they were using,” Giffin said.

Giffin attributed the declines to a prolonged period of dry weather, which has resulted in less snowmelt replenishing the region’s groundwater supply, along with more people using the groundwater in rural Deschutes County and less water seeping into the system as more irrigation canals get piped.

He said the average marijuana grower uses about 3,000 gallons of groundwater per day, significantly more than most homes, but less than many agricultural uses.

“That is just a drop in the bucket,” Giffin said.