Water Quality

The Oregon Water Quality Index analyzes a defined set of water quality variables and produces a score describing general water quality for a particular monitoring site in the ambient monitoring network. In this map, scores are color-coded to indicate water quality status, and evaluated for improving or declining trends at each site. The status and trend analyses incorporate 10 years (currently water years 2007-2016) of water quality data.

View Water Quality Index Map in a separate window

OWQI Reports and Documents

Reference Materials

Data Downloads

2016 Basin Summary Tables

Raw Data and Historical Status and Trends


Lesley Merrick, 503-693-5724
Dan Brown, 503-693-5743