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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)

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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.
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Keywords stream, flow, water, trend, water quality, monitoring, quality, freshwater
WEB PAGE Water Quality Index for rivers & streams