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Groundwater Protection in Oregon

Groundwater is vital to the public health, economy, and environment of Oregon. Oregon’s groundwater has many uses, including drinking water and other household uses, irrigation for crops, numerous industrial and commercial uses, and base flow to streams. In Oregon, the Department of Environmental Quality has the primary authority for groundwater quality protection.

Groundwater monitoring

Groundwater is essential to the economic viability and livability of many Oregon communities. groundwater is used for irrigation, drinking water, municipal water supplies, and other uses. It serves as the water supply for over 70 percent of residents in Oregon. More than 600,000 Oregonians get their drinking water from individual private water wells.

Groundwater also influences the quality of many Oregon rivers and streams. Especially during the dry summer months, groundwater inflows affect stream flow, chemistry and temperature which in turn determine the quality of surface waters used for drinking water, irrigation and recreation. High quality inflows of groundwater are essential for maintaining cold-water fisheries in many streams.

​Groundwater contamination is a serious issue in some areas of Oregon. Many agencies study the quantity and quality of Oregon’s groundwater resources. Ambient groundwater quality studies over the past 20 years and routine monitoring of public water supplies found 35 of 45 study areas show some impairment or reason for concern. Nitrate is the most commonly detected contaminant, followed by pesticides, volatile organic compounds, and bacteria. Data collected show that twenty-four percent of 1156 wells sampled statewide exceed the drinking water standard for arsenic. Sixteen percent of 2187 wells sampled exceed the drinking water standard for nitrate. Thirty-three percent of Willamette Valley rural wells contain at least one pesticide. In all, the program produces over 5,000 data points each year.​​

​DEQ also protects groundwater resources through a number of water quality and land quality permit programs. Each year monitoring staff visit approximately fifteen of more than 75 statewide solid waste landfill sites. 

Samples are analyzed for a broad range of contaminants such as organic pollutants, metals and other contaminants of concern. Many landfills were initially monitored by DEQ staff. Now, the primary role of DEQ groundwater monitoring is to provide oversight and perform routine audits on various contractors that complete this valuable monitoring work at these facilities. Monitoring data from landfills are used by regional DEQ hydrogeologists, engineers and permit staff to evaluate compliance with solid waste permit requirements.​​

​DEQ staff worked with Department of Human Services to evaluate source water quality at several public water supply systems located throughout Oregon. DEQ chemists assessed samples collected from these aquifers for a broad spectrum of contaminants including pesticides, pharmaceuticals and personal care products, many of which have no federal drinking water standards. In another effort, DEQ staff worked collaboratively with DHS to quickly assess water quality at more than 100 domestic wells in Douglas County. These efforts yielded important information on the quality of drinking water supplies for Oregonians living in rural communities.​​

Who does what?

Although DEQ has primary responsibility for groundwater protection, Oregon’s groundwater quality protection program consists of a number of programs spread among different state agencies.  Four state agencies, the Department of Environmental Quality, the Oregon Department of Human Services Drinking Water Program, the Water Resources Division, and the Oregon Department of Agriculture implement the majority of federal and state programs relating to groundwater.  

​In addition to implementing the following programs, it is the Water Quality Division's responsibility to oversee the implementation of the Groundwater Quality Protection Act and rules. DEQ also permits artificial groundwater recharge projects, as needed, and provides input to WRD for aquifer storage and recovery projects. The Laboratory Division provides monitoring support to many program areas relating to groundwater, including groundwater monitoring for the Groundwater Management Areas.​

Drinking Water Protection Program 

  • Implemented by DEQ and DHS-DWP for Oregon.
  • Requires states to develop Source Water Assessments for public water supply systems (surface water and groundwater sources).

Groundwater Management Areas  

  • Designated by DEQ when groundwater in an area has elevated contaminant concentrations resulting, at least in part, from non-point sources.
  • Oregon has designated three GWMAs because of elevated nitrate concentrations in groundwater. 

Onsite Sewage Disposal Program 

  • Regulates the installation of individual on-site disposal systems with procedures to protect groundwater.
  • In some areas, the county runs the program and issues permits under DEQ guidelines.

Underground Injection Control Program 

  • Regulates waste injection into the ground with groundwater protection requirements.

Wastewater Permitting Program 

  • Regulates the disposal of wastewater through federal NPDES and state WPCF permits.
  • Facilities having the potential to impact groundwater are required to have a groundwater quality protection program (implemented by DEQ regional offices). 

Water Reuse Program 

  • Prescribes treatment and monitoring requirements for the beneficial use of wastewater.

Biosolids Management 

  • Encourages the beneficial use of biosolids to protect public health and the environment.
  • Almost all biosolids derived from domestic wastewater treatment facilities in Oregon are applied to the land for agricultural purposes.

Solid Waste Program 

  • Permits the siting and management of new industrial and municipal solid waste facilities. 
  • New facilities are required to conduct site investigations and water quality monitoring to determine the landfill’s potential to impact groundwater.
  • Facilities which pose a threat to groundwater quality are required to perform groundwater monitoring and reporting and install synthetic liners and leachate collection and treatment systems.

Hazardous Waste Program 

  • Administers statutes and rules to regulate and permit the generation, storage, transportation, treatment and disposal of hazardous waste.

Cleanup Program 

  • Provides for identification and remediation of sites contaminated with hazardous substances.
  • Incorporates Site Assessment, Voluntary Cleanup, Independent Cleanup, Brownfields, Dry Cleaners, Orphans, and Site Response. 

Tanks Program

  • Incorporates the Underground Storage Tank Program, Leaking Underground Storage Tank Program, and the Heating Oil Tank Program.
  • Leaking UST Program specifically deals with cleanup of soil and groundwater contamination from underground storage tanks.   


Oregon Department of Human Services Drinking Water Program

  • Administers the Safe Drinking Water Act programs (including Public Water System monitoring, Real Estate Transaction Well-Testing, Drinking Water Protection Program (with DEQ), Wellhead Protection Area Certification, & provides technical assistance to to PWS on well construction issues).
  • Provides input to WRD on Artificial Groundwater Recharge and ASR projects.

 Oregon Department of Water Resources

  • Allocates groundwater and surface water rights.
  • Provides water resource data.
  • Administers the statutes and rules governing monitoring and supply well construction, usage, & abandonment, low temperature geothermal wells, and ASR.
  • Conducts extensive groundwater investigations.

Oregon Department of Agriculture

  •  Has lead responsibility for water quality protection in areas of agricultural activities.
  • Regulates pesticide registration and use, develops agricultural water quality management plans, regulates and permits confined animal feeding operations, and administers ODA grants for groundwater research and development.

Oregon State University Extension Service

  • Conducts research and provides information related to agricultural and land-use issues, including studies of agricultural practices impact on groundwater and monitoring groundwater for nitrate. 

Oregon Department of Land Conservation and Development

  • Responsible for reviewing local land use plans and regulations for compliance with the statewide planning goals.
  • Several statewide planning goals require local governments to establish policies and implement measures necessary to protect groundwater.

Oregon Department of Geology and Mineral Industries

  • Permitting agency for gas and oil wells, mining development and reclamation, and geothermal wells (for systems with temperatures 250 degrees F or greater or depths 2,000 feet or deeper). 
  • Coordinates with DEQ and other agencies to address groundwater issues related to permitting. 

Oregon Department of Energy

  • Regulates energy facilities, radioactive wastes and the transport of radioactive material.
  • Coordinates these activities with DEQ and other state agencies, as applicable.​

Groundwater protection in Oregon occurs at the federal, state and local level through various agencies. Oregon administers many groundwater-related Federal programs including the Clean Water Act; Safe Drinking Water Act; Resource Conservation and Recovery Act; Comprehensive Environmental Response, Compensation, and Liability Act; and Federal Insecticide, Fungicide and Rodenticide Act. 

In addition to these federal laws, Oregon has its own laws and regulations relating to groundwater protection. Similarly, local governments may regulate groundwater through local ordinances in addition to assisting state and federal agencies in enforcing groundwater regulations. Groundwater protection can also occur through non-regulatory means such as education, voluntary programs, and local groups.  

State regulations

Oregon Groundwater Quality Protection Act of 1989 - The goal of the Oregon Groundwater Quality Protection Act is to prevent contamination of groundwater and to conserve, restore, and maintain Oregon’s groundwater resource for present and future uses. 

Federal regulations


Current news

Free well water testing information
The Oregon Department of Environmental Quality is offering free well water quality testing in Klamath Basin as part of a groundwater resource study. If you own a well in this study area and want to participate, please contact us.

Contact

Groundwater Monitoring Program 
503-693-5736

Groundwater Management Areas 
Groundwater protection and cleanup
  • Hazardous substances (Including cleanup and site response information) - email
  • Solid waste facilities email
  • Underground storage tanks - email
    Helpline: 800-742-7878 or 503-229-6652
  • Water quality permitted facilities
    • Eastern Region - Rick Hill, 541-278-4625 or 800-304-3513
    • Northwest Region – 503-229-5263  
Statewide Groundwater Quality Monitoring Program

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