Pesticides and water quality
- As the state lead agency for FIFRA (Federal Insecticide, Fungicide, Rodenticide Act), the Oregon Department of Agriculture (ODA) Pesticides Program holds the primary responsibility for pesticide registration and use regulation within the state of Oregon.
- As the Environmental Protection Agency (EPA) designated state lead agency for pesticides, ODA is responsible for overseeing the development and implementation of the Pesticide Management Plan (PMP) for the state of Oregon as stipulated in the annual EPA and ODA Consolidated Pesticide Cooperative Agreement.
In Oregon, statutory authority for development and enforcement of water quality policies related to pesticides lies with several different state agencies, including the Oregon Department of Environmental Quality (DEQ), the Oregon Department of Forestry (ODF), the Oregon Health Authority (OHA), the Oregon Watershed Enhancement Board (OWEB), and ODA. An interagency team, the Water Quality Pesticide Management Team (WQPMT), composed of representatives from these agencies has been formed to efficiently address the protection of waters of the state from pesticide contamination.
WQPMT facilitates and coordinates water quality activities such as monitoring, analysis and interpretation of data, effective response measures, and management solutions. The initial goal of the WQPMT was to develop and implement a statewide pesticide management plan (PMP), which was approved by EPA in 2011.
Water Quality Pesticide Management Team (WQPMT)
Addresses water quality issues in Oregon related to pesticide use with representatives from the following agencies:
- Oregon Department of Agriculture (ODA)
- Department of Forestry (ODF)
- Department of Environmental Quality (DEQ)
- Oregon Health Authority (OHA)
- Oregon Watershed Enhancement Board (OWEB)
- Oregon State University (OSU)
WQPMT meetings
The WQPMT meets on the third Thursday every other month at locations around the state. Meeting minutes are posted below, beginning with February 2019.
WQPMT goals and objectives
- Identify and prioritize higher risk pesticides, use patterns, and watersheds
- Facilitate water quality monitoring plans, resources, and activities
- Annually evaluate pesticide water monitoring results
- Facilitate management solutions and outreach and educational activities through local stakeholder groups to prevent or reduce pesticide contamination in water
- Improve communication with state and federal agencies, farmers, commodity groups, OSU Extension, environmental groups, industry, local water entities, and others about pesticides and water quality
- Measure progress and try new strategies if necessary
Pesticides of High Concern (PHC), Pesticides of Moderate Concern (PMC), and Pesticides of Low Concern (PLC)
PHC: A pesticide that exceeds 50% of an established benchmark concentration, indicating a possible risk to human or ecological life in 30% or more of the Pesticide Stewardship Partnership (PSP) watersheds. This pesticide may also be referred to by the US EPA as Pesticides of Concern (POC).
PMC: A pesticide that exceeds 50% of an established benchmark concentration, indicating a possible risk to human or ecological life in at least one PSP watershed but less than 30% of these watersheds.
PLC: A pesticide that has been detected at a frequency of less than 35%, but has not exceeded 50% of any established benchmark.
Nationwide, state agencies originally compiled a list of 57 active ingredients or groups of active ingredients that were most likely to affect water quality. The WQPMT added additional pesticides that had the potential to raise concerns in Oregon, resulting in a current total of 72. Of these 72 active ingredients, WQPMT annually selects a subset of this list for further evaluation.
In 2019, the WQPMT modified its methodology to assess the status of pesticides detected in Oregon’s waterbodies. This methodology is based on the concentration of a pesticide and the frequency at which it was detected. This analysis is conducted for each watershed participating in the PSP. This analysis provides for a watershed specific designation of PHC, PMC, and PLC. If a pesticide is determined to be a PHC in 30% or more of the participating watershed, it is designated as a statewide PHC. Pesticides are assessed every year using the last three years of data collected through the PSP and other sources meeting quality assurance requirements.
Overall objectives
- Identify and characterize pesticides that may pose a risk to water resources
- Actively manage them by facilitating efforts to reduce or prevent contamination below the reference point (an established benchmark or standard)
- Demonstrate how management efforts are keeping concentrations at acceptable levels
Statewide pesticides of High Concern, 2017-20
- Diazinon
- Dimethenamid-p
- Diuron
- Imidacloprid
- Oxyfluorfen
Statewide pesticides of Moderate Concern, 2017-20
- Atrazine
- Bifenthrin
- Carbaryl
- Dimethoate
- Ethoprop
- Glyphosate
- Linuron
- Metsulfuron methyl
- Malathion
- Mecoprop-p (MCPP-p)
- Metolachlor
- Pendimethalin
- Prometryn
- Pyripoxfen
- Simazine
- Sulfometuron methyl
- 2,6-dichlorobenzamide (degradate of Dichlobenil)
- AMPA (degradate of Glyphosate)
- Deisopropylatrazine (degradate of Atrazine and Simazine)
EPA aquatic life benchmarks
The aquatic life benchmarks (for freshwater species) provided in the table are based on toxicity values reviewed by EPA and used in the Agency's most recent risk assessments developed as part of the decision-making process for pesticide registration. EPA aquatic life benchmarks
EPA human health benchmarks for pesticides
The table includes benchmarks for acute (one-day) and chronic (lifetime) exposures for the most sensitive populations from exposure to pesticides that may be found in surface or ground water sources of drinking water. Human health benchmarks for pesticides
Pesticide Management Plan for Water Quality Protection
The plan outlines the roles, policies and legal authorities of each government agency with the responsibilities for protecting Oregon's water resources from pesticides and the process by which these activities will be coordinated. Water quality pesticide management plan
Pesticide Stewardship Partnership (PSP) letter of support from Oregon Departments of Agriculture (ODA), Forestry (ODF), and Environmental Quality (DEQ)
Stakeholder letter
WQPMT Status Reports
Water Quality Pesticide Management Team: Year End Summary of Accomplishments (2018)
WQPMT 2018 Summary