Oregon’s efforts to crack down on unlawful irrigation by cannabis producers may be starting to pay off, according to statistics tracked by state regulators.

Investigations of licensed hemp farmers uncovered water rights violations at 10 grow sites in 2022, down from 41 sites in 2021 and 61 sites in 2020, according to the state’s Water Resources Department.

“Part of this has to do with the market changes, but overall there are less and less violations, and I think it speaks highly of our department’s interaction with the growers,” said Scott Prose, hemp specialist and assistant watermaster at the agency.

Hemp production has fallen due to an oversupply and low prices, but violations have also dropped as a percentage of the total number of sites investigated.

Violations were found at 8% of the hemp operations investigated by OWRD in 2022, compared to 24% in 2021 and 33% in 2020.

“It points to our work having an impact on the resource and on having compliance,” Prose said during a recent meeting of the Oregon Water Resources Commission, which oversees the agency.

Violations were more common among licensed growers of marijuana, a psychoactive type of cannabis that’s legal in Oregon but banned by the federal government.

Last year, 81 violations were found at licensed marijuana sites, representing 19% of the 424 operations investigated.

Water regulators investigated another 128 unregistered cannabis sites — presumably producing illegal marijuana — often as part of raids carried out by law enforcement agencies.

It takes a lot of time for staff to investigate unregistered sites, Prose said.

The OWRD has a tougher time gaining access and examining grow sites “tucked away on hillsides,” which are often owned by absentees living out of the state or country, said Justin Dillon, the agency’s southwest regional manager.

“If it’s gated and it’s got a fence and it says ‘no trespassing,’ our job starts to get really hard as far as investigating complaints,” Dillon said, adding that delays are often frustrating for community members who want to see timely action.

Of the unregistered cannabis sites investigated by OWRD, 46% were found to have water rights violations, which is more than double the rate for licensed marijuana and nearly six times the rate for licensed hemp.

“These are folks who are outside the law already, so that may not be a surprise,” Prose said.

However, the agency does see indicators that marijuana and hemp reform laws passed in recent years are having an effect on water usage in cannabis production.

Following Oregon’s legalization of marijuana in 2015 and the nationwide legalization of hemp in 2018, purchases of bulk water for delivery in Jackson County rose sharply — correlating with spiking complaints about unregistered grow sites, Dillon said.

Complaints about illegal marijuana producers illegally using water are particularly prevalent in Jackson and Josephine counties in southwest Oregon.

State lawmakers tightened regulations on water deliveries in 2021 after hearing that bulk purchases were contributing to illegal marijuana production that year. They’ve also increased funding to enforce cannabis regulations.

Bulk water usage hit a high point in the summer of 2021, but the volume of water sold this way decreased by roughly half in 2022, Dillon said.

“Lots of variables in that drop, but it coincides with the new legislation, the deployment of our new staff, the assistant watermasters and the increase in grant funding to the law enforcement agencies,” he said.

The fight against illegal cannabis has strengthened OWRD’s cooperation with law enforcement and other agencies while tremendously adding to its workload, Dillon said.

Even after unlawful water appropriation is stopped, problems from illegal grow sites persist, such as chemicals leaching into the aquifer, he said.

“That’s something we’re faced with statewide, is how we repair the environmental damage,” Dillon said.

Illegal water use by cannabis growers has grown rapidly, understandably alarming communities, but it’d be helpful to know the rate of violations among other water users, said Eric Quaempts, a commissioner and natural resources director for the Confederated Tribes of the Umatilla Reservation.

While the complaints about cannabis producers are numerous, problems among larger-scale water users may actually be more concerning as a whole, he said.

“Are we paying attention to the biggest problems?” Quaempts asked. “We may find that there are, or are not, bigger problems.”