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Water Quality Index

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. Scores correspond to a water quality status and are evaluated for improving or declining trends at each site. The status and trend analyses incorporate 10 years (currently water years 2013-2022) of water quality data.

Oregon water quality reports and documents

Reference materials

Data downloads

Basin summary tables

Raw Data and Historical Status and Trends


Kat Maloney, water quality monitoring