Publications Home

Publication Summary

Our Ecology website has changed, which can cause broken links.
To report these, please contact us with the publication and broken link.


A Water Quality Index for Ecology's Stream Monitoring Program

Publication number Date Published
02-03-052December 2002
VIEW NOW: A Water Quality Index for Ecology's Stream Monitoring Program (Number of pages: 23) (Publication Size: 406KB)

Trouble viewing? Try these free options.
Author(s) Hallock, D.
Description The Water Quality Index (WQI) is intended as a tool to summarize and report Ecology's Freshwater Monitoring Unit's routine stream monitoring data. The WQI is a unitless number ranging from 1 to 100; a higher number is indicative of better water quality. Scores are determined for temperature, pH, fecal coliform bacteria, dissolved oxygen, total suspended sediment, turbidity, total phosphorus, and total nitrogen. Constituent scores are then combined and results aggregated over time to produce a single yearly score for each sample station. This report presents the methodology behind the WQI and the results of a trend analysis on monthly WQI scores at our long-term monitoring stations.
REQUEST A COPY The mission of the Department of Ecology is to protect, preserve, and enhance Washington’s environment. To help us meet that goal, please consider the environment before you print or request a copy.

Accessibility Options
Persons with hearing loss can call 711 for Washington Relay Service
Persons with a speech disability can call 877-833-6341
Contact Joan LeTourneau at 360-407-6764 or
Keywords stream, flow, water, trend, water quality, monitoring, quality, freshwater
WEB PAGE Water Quality Index for rivers & streams