Update of Columbia River flow and temperature data measured at Priest Rapids Dam and Vernita Bridge

Columbia River temperatures and flow rates are collected daily at Priest Rapids Dam and Vernita Bridge. These data are necessary for assessing trends or changes in river conditions downstream of Priest Rapids Dam. In order to analyze this data, Pacific Northwest Laboratory developed a computerized data base using existing US Geological Survey flow and temperature records at Priest Rapids Dam and Vernita Bridge. Daily-averaged temperature and daily flow information on the Columbia River just downstream of Priest Rapids Dam and upstream of river mile 380 were collected and stored in a data base. A newly developed computer model, COLSTAT (Columbia River Statistical Update), used the data base to statistically analyze temperature and flow conditions by computing the frequency of occurrence and duration of selected temperatures and flow rates for the Columbia River. Information regarding the data base is presented, as well as, a description of the COLSTAT model.