Water Quality

​​​view of a lake 
 
The Oregon Department of Environmental Quality submitted its 2018/2020 Integrated Report in April 2020, to the  U.S. Environmental Protection Agency. The federal Clean Water Act requires Oregon to report on the quality of its surface waters every two years. Although not a written report, the Integrated Report is a reporting of the status of water quality in Oregon and a list of waters considered to be impaired. The 2018/2020 Integrated Report will be in effect after EPA approval. See the Water Quality Assessment page for more information.
 

The Integrated Report can be accessed in four ways:

  • An interactive story map provides an overview of the water quality assessment process and displays results in terms of supporting beneficial uses.
  • An interactive web map application displays the Integrated Report by overall status of an assessment unit. For example, if an assessment unit is classified as impaired, one or more assessed pollutants do not meet the interpretation of water quality standards outlined in the methodology. The application also provides all applicable Water Quality Standards and TMDL information. Instructions for the web map application.
  • An online searchable database that provides categorical assessment conclusions for all assessed parameters.
  • An ArcGIS 10.5 Assessment Geodatabase spatially displays information from Oregon’s draft 2018/2020 Integrated Report. This database also includes a layer that spatially displays DEQ’s Water Quality Standards
  • Raw data used in Oregon’s 2018/2020 Draft Integrated Report can also be accessed through DEQ’s Ambient Water Quality Monitoring Portal.

For more information


The displays and access to information have been updated:

  • The watershed assessment units on the Story Map and Web Map are now represented as shaded areas. This update reflects the fact that conclusions for watershed assessment units indicate there is an assessment within the sub-watershed (HUC-12) and conclusions may not reflect all streams in the unit.
  • The Web Map display now automatically shows monitoring locations at certain zoom levels.
  • The Assessment Database is updated to enable filtering by attainment status and beneficial use.  Users also have the ability to download raw data used in the 2018/2020 assessments, from the link at the top of the database.

Specific assessments have been revised in response to comments received:

  • The Columbia Slough assessment unit, or OR_WS_170900120201_02_104554, was split in two based on information indicating that these two segments are hydrologically distinct. The new units are OR_WS_170900120201_02_104554.1 and OR_WS_170900120201_02_104554.2.
  • Chlordane data was reassessed against the human health criteria based on errors identified in the original assessment. DEQ reassessed chlordane data against human health criteria after identifying errors in the original assessment.
  • Oregon is including Oregon territorial marine waters as having insufficient data (Category 3B) for hypoxia in addition to ocean acidification. DEQ determined that marine hypoxia is a potential concern in Oregon’s coastal waters, and that the data are insufficient to identify the water as impaired and in need of a TMDL. DEQ proposed to list Oregon marine territorial waters as “of potential concern” (Category 3B) for ocean hypoxia.
  • DEQ made corrections to individual assessments in response to public comments.

​​The federal Clean Water Act requires the Oregon Department of Environmental Quality to assess Oregon’s water quality and prepare a report every two years. The Integrated Report is a database report that combines reporting information for the Clean Water Act Section 305(b) assessment of all water bodies and the Section 303(d) list of water bodies that do not meet water quality standards. The 303(d) list represents where pollution reduction plans called Total Maximum Daily Loads are needed.
 
The 2018/2020, Integrated Report represents the state’s most comprehensive evaluation of water quality data and information about Oregon’s waters. DEQ assessed this data and information to determine whether Oregon’s waters contain pollutants at levels that exceed protective water quality standards and do not support their beneficial uses. To complete this assessment, DEQ reviewed and assessed readily available data and information for the time period Jan. 1, 2008, through Dec. 31, 2017, using the Methodology for Oregon’s 2018 Water Quality Report and List of Water Quality Limited Waters.
 
The 2018/2020 Integrated Report categorizes all assessed waterbodies. DEQ evaluated data on whether Oregon’s waters are of a high enough quality to meet the most common beneficial uses, such as supporting aquatic life, providing drinking water or supporting recreation. Waterbodies that exceed protective water quality standards are identified as impaired and placed on the 303(d) list. Identifying a waterbody as impaired initiates the prioritization and development of a TMDL.
 
The categories are:

  • Category 1: All beneficial uses are supported and none are known to be impaired. Oregon does not have sufficiently robust data to be able to use this category.
  • Category 2: At least one core beneficial use is supported and none are known to be impaired.
  • Category 3: Not enough information to determine beneficial use support.
  • Category 4: Available data and/or information indicate that at least one designated use is not being supported but a TMDL is not needed.
  • Category 5: At least one beneficial use is not supported and a TMDL is needed.

The public comment period for the draft methodology closed on June 28, 2018.

The call for data closed on July 25, 2018.  In all, DEQ evaluated over 6.5 million data points from 74 organizations for the draft Integrated Report.

In 2016, DEQ undertook a major effort to update and improve the Integrated Report process, addressing longstanding issues, and increasing accessibility. DEQ will be updating the assessment methodology for every cycle, which is typically every two years.  For information on its 2022 proposed methodology updates, please see the 2022 Integrated Report page coming soon.