SALEM — Oregon regulators have come under fire from agriculture and forestry advocates for allegedly misrepresenting information about pesticides in waterways to the public.

A new online “data viewer” displays information about pesticide detected in 12 river basins by the state’s Department of Environmental Quality and Department of Agriculture.

The state government promoted the interactive tool as helping “Oregonians who want to know what pesticides are in their local streams,” but several natural resource organizations say that’s an inaccurate characterization of the data.

“We dug into what the tool is showing and how it is being presented, and it is so misleading,” said Mary Anne Cooper, vice president of government affairs for the Oregon Farm Bureau. “It has a high likelihood of being used against producers on the ground.”

The tool invites data to be taken “out of context” and “will surely result in unjustified concerns over water quality,” according to the Oregon Farm Bureau, Oregon Association of Nurseries, Oregon Forest Industries Council and Oregonians for Food and Shelter agribusiness group.

“The presentation is almost what we’d expect from activist groups,” Cooper said.

The problem is not that the data is incorrect or that it’s being disclosed, since the information always has been publicly available, she said.

Rather, the online tool fails to explain that data was collected at highly targeted locations and times when pesticides were more likely to be detected, said Katie Murray, executive director of Oregonians for Food and Shelter.

“This is a very biased data set — intentionally biased,” Murray said.

The data was gathered as part of the state’s Pesticide Stewardship Partnership, which was formed by DEQ, ODA and other agencies in 2000 to support voluntary improvements to pesticide practices.

By taking samples immediately downstream from farms after spring rains, for example, the program seeks to maximize detections, according to industry groups. Pesticide users can then see if their strategies to keep chemicals out of waterways are proving effective.

To monitor for pesticides on a watershed-scale, however, samples would need to be taken at random sites and times, with the data likely reflecting less frequent pesticide detections at lower concentrations, they said. Without these caveats, though, the government’s online data viewer creates an exaggerated impression of pesticide levels and health risks.

“That’s not what that data meant. It’s telling the wrong story,” Murray said. “DEQ is actively presenting this data as if we can generalize from it about the safety of the water and we cannot. They’re encouraging people to misunderstand this data.”

A stakeholder advisory committee raised concerns about such misperceptions, which government officials seem to have ignored, critics say. The Pesticide Stewardship Partnership relies on cooperation from farmers and other pesticide users, but the online tool threatens to undermine that trust.

“Nobody knew that is how they’d use the data 10 to 20 years down the road,” Murray said.

The Pesticide Stewardship Partnership’s data-driven education has been more effective at reducing water pesticide levels than standard regulatory approaches, Cooper said. In recent years, however, the program hasn’t engaged as closely with individual farmers.

Now, the data viewer will likely serve as a cudgel in legislative disputes over pesticides, particularly since it implies “even the agencies acknowledge this is a problem” with waterway pollution, she said.

“You’re just going to inflame situations,” Cooper said. “It makes it hard to see how they will explain the full picture to lawmakers and the public.”

When asked about these concerns, the DEQ said the tool provides “additional context” for the “current and historic monitoring data,” such as federal benchmarks for protecting “the health of aquatic life and humans.”

“To aid the public’s understanding of the data, and to address concerns that the raw data could be misinterpreted or misused, DEQ displays the data in the manner consistent with how DEQ and ODA interpret the data to manage the program,” the agency said in an email.

The ODA said the data tool is “not intended to be a comprehensive source of pesticide distribution in state waters,” but helps pesticide users and other partners achieve “measurable environmental improvements.”

In response to feedback from stakeholders, a “popup” explaining the “context and scope of the data” now appears when the online tool is accessed, the agency said in an email.

The data viewer was developed by DEQ to “provide transparency and easier access” to program data, and the ODA is “committed to working with DEQ to periodically update” the tool, the agency said.