Publication Summary

At the request of the Department of Ecology, Central Regional Office, a review and statistical analysis of water quality data from the Wenatchee River basin was done. Graphical data summaries of selected parameters from both long-term sites on the Wenatchee River are presented.

At the request of the Department of Ecology, Central Regional Office, a review and statistical analysis of water quality data from the Wenatchee River basin was done. Graphical data summaries of selected parameters from both long-term sites on the Wenatchee River are presented.

Linear trend analysis revealed a significant increasing trend in percent saturation dissolved oxygen and pH at the Wenatchee River site near Wenatchee (45A070). Also, marginal trends (P<0.10) in temperature (increasing) and nitrate/nitrite concentration (decreasing) were detected at this site. A significant upward trend in pH and downward trend in nitrate/nitrite concentration were detected in the data from the Wenatchee River site near Tumwater Campground, upstream from Leavenworth (45A110). Differences in median value between these sites were found in temperature (1.2°C), percent saturation of dissolved oxygen (6%), pH (0.3), nitrate/nitrite concentration (0.057 mg N/L), total suspended solids (1.0 mg/L) and fecal coliform (5/100 mL). The major concern seen from this analysis is the high temperature and high pH values at the site near Wenatchee.