Why water temperature? Temperature can be an indicator for many other potential issues within a river system, primarily the amount of oxygen the water can hold. Higher temperature water holds less dissolved oxygen than cold water—like how higher altitudes have less oxygen and can give you altitude sickness!

The NCWA and its partners have been monitoring water temperature for many years, starting around the Ecola Creek watershed in the early 2000’s with dedicated volunteers. The NCWA began a formal water temperature monitoring program in 2016, and grew the program to include sites within all 4 watersheds served by the organization by 2018. Now that we have several years of summer temperature data we are beginning to analyze it and designing restoration projects in areas that need help staying cool.

Below is a map of our 24 temperature monitoring sites, with streams color-coded for average summer temperatures over the years ranging from red (hottest) to blue (coolest). Red stars represent the known limits of regular tidal influence (head of tide) and black dots are our monitoring sites—click on them to see their names.