Georgetown Tribal Council staff members just got back from the fall trip out to Georgetown to complete water testing.   We have been collecting information from the monitoring well sights since 2008, and the freshwater sites since 2012.  In this article we will  share  some of the interesting trends we are starting to see in the freshwater sites.

For a complete set of water quality data for Georgetown as well as other communities on the middle Kuskokwim, please visit our online map and database here.

Figure 1 below shows the temperatures recorded in the Kuskokwim River, just in front of Georgetown (KR-1), as well as just up from  the mouth of the George River (GR-1) from 2012 to 2016.   Data is collected in the early part of the summer and in the beginning of the fall each year.  What do all of these lines mean?  Well in terms of preferred salmon water conditions: If the water temperature is found to be above the bright red line, it means that the water is too warm for migrating salmon and rearing areas.  If the water temperature is above the dark red line, it means that the water is too warm for spawning and egg/fry incubation.

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Figure 1: Temperature Recorded at Kuskokwim & George Rivers, as related to maximum temperature ranges for salmon in various stages of their life cycle

 

All of the recorded temperatures that fall above those lines are labeled in the graph above. Note that on the George River, since 2013, each recording in July has fallen above that dark red line.  For the Kuskokwim River, the temperatures are coming in above both  the bright red and the dark red, meaning conditions would not be good for salmon migrating through the area or spawning there.

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Figure 2: Dissolved Oxygen Levels at George & Kuskokwim Rivers, as related to range set by AK DEC  Water Quality standards

 

Figure 2 shows Dissolved oxygen levels at these same sites. The only time Dissolved oxygen levels fell outside of the range set by AK DEC water quality standards was in September of this year, and it was above the maximum level, which is less concerning than if it would fall below the range.

pH, salinity & total dissolved solids are other parameters we measure, and those levels are all looking good.

It is worth asking if the rising temperature in the rivers are due to a warming climate.  Scenarios Network for Alaska Planning (SNAP)  temperature predictions show for Georgetown (figure 3) that temperature increases will continue and it seems to agree that July is one of the warmer months.  To view the interactive version of this graph visit  the SNAP website – graphs are available for most communities in Alaska. It seems only likely that if temperatures are on the rise, water temperatures would follow suit.

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Figure 3: SNAP predictions of temperatures rising in Georgetown

 

For more information about the parameters we measure, visit our website.  Stay tuned for more information about what kind of metals we are finding in both freshwater and monitoring well sites.  We will post information once we receive results from Test America from the trip this September.

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