Water Quality Programs

Between 1999 and 2005, each public water system in Oregon received a source water assessment report completed by the Oregon Department of Environmental Quality and Oregon Health Authority drinking water programs. The assessment gives the water system and community information on the watershed or recharge area that supplies the well, spring or intake (the “drinking water source area”) and identifies potential risks within the source area. 

In 2016 and 2017, the agencies are completing Updated Source Water Assessments to provide the water systems and communities more detailed information on the watershed or recharge area that supplies their well, spring or intake. DEQ opened public comment on the content and format of an USWA prototype on May 18, 2016.  This public comment period allowed partner state agencies, stakeholders, and public water providers an opportunity to help make the information more useful and relevant.  Comments received were used to improve the document.  The prototype was finalized in August 2016.

Updated Source Water Assessments will be provided to all public water systems using surface water and are posted at the link below as they are completed.  For groundwater systems, OHA has prioritized new Community and Non-Transient Non-Community water systems and systems that have added a new water source since their original source water assessment was completed.  For groundwater system reports, contact Drue Edney, OHA, at 541-726-2587 ext. 25.
Public water systems and local communities can use the information in the assessments to voluntarily develop place-based plans and implement drinking water protection strategies.​ 

Source Water Assessment - 2000-2005

Updated Source Water Assessments - 2016-2017

PWS 00554 City of Nehalem PWS 00254 City of Depoe Bay
PWS 00568 Beverly Beach Water District
PWS 00564 Bay Hills Water Association
PWS 00722 Hiland Water Corp. – Boulder Creek
PWS 00925 Southwest Lincoln County Water District
PWS 01072 Johnson Creek Water Service
PWS 00603 Panther Creek Water District
PWS 00609 Pacific City Joint Water-Sanitary Authority
PWS 00610 Tierra Del Mar Water Company
PWS 00556 Netarts Water District
PWS 00199 Beaver Water District
PWS 00893 Tillamook Water Department
PWS 00898 Timber Water Association
PWS 00124 Fishhawk Lake Reserve and Community
PWS 00922 City of Vernonia
PWS 05737 Berndt Creek Water Corp.
PWS 00055 City of Astoria
PWS 00063 Wickiup Water District
PWS 00062 Youngs River Lewis & Clark Water District
PWS 00932 City of Warrenton
As part of the Updated Source Water Assessments, DEQ developed a statewide land use/ownership GIS layer to evaluate land cover in drinking water source areas.  The land use/ownership layer is a combination of multiple datasets that have been modified by grouping land owner categories in order to simplify data display on the map. See Notes for data sources, methods, and data limitations. The land use/ownership layer can also be viewed using DEQ’s interactive map viewer​. Statewide and individual public water systems source area summaries are provided below: Maps for each public water system are provided in the Updated Source Water Assessment report.

Surface water: 
Table 1: Summary of Land Use/Ownership in Oregon Drinking Water Source Areas served by Surface Water Sources
This dataset includes total square miles and total percentage of land use for each generalized land use/ownership category for each surface water source area. Excel table can be sorted by watershed, county, population served, or specific land use. See Notes for data sources, methods, and data limitations. 

The high soil erosion potential data is based on Natural Resource Conservation Service and National Forest Service data for slope (>30%) and “K-factor” (of 0.25 or greater) which quantifies the susceptibility of soil particles to detachment and movement by water including the effects of rainfall, runoff and infiltration. Soils with "high" soil erosion potential are considered more sensitive to ground disturbance. For future assessment on flatter terrains or in areas where K-factor is not available, a comparable approach will be developed and vetted with input from Oregon Department of Agriculture, Natural Resource Conservation Service and others.

Expanded views:

This dataset includes earth and debris slides, flows, slumps, falls and complex landslide types (but not rock material landslide deposits) from the Statewide Landslide Information Database for Oregon.  Additional information and data limitations can be found at http://www.oregongeology.org/sub/slido/. Maps for each public water system are provided in the Updated Source Water Assessment report..  OR DEQ's Water Quality Program is currently working with DOGAMI to develop and provide a more detailed landslide potential analysis for public water systems. Contact Oregon DEQ's Environmental Solutions Division/Water Quality Program for further information on the analysis. 

Expanded views:

EPA and Oregon regulations that protect public drinking water systems do not apply to private water supplies, however knowing where domestic withdrawals occur is important to identify water users in watersheds and protect public health. This map shows the density of “domestic”(private) points of surface water diversion identified in the Oregon Water Resources Department water rights database.  It is important to note that this is likely a subset of all domestic water users as many domestic water users may not hold water rights. 
This map shows the types of drinking water treatment technologies employed by public water systems in Oregon and their relative susceptibility to particulate matter and turbidity in the water.


Source Water Assessment Inventory Results, June 2005
Source Water Assessment Inventory Results as of June 2005 for Potential Contaminant Sources identified in Oregon Drinking Water Source Areas for Community and Non-transient Non-community Public Water Systems