Seasonal Water Quality Data Collection in the Upper Gallatin Reveals a More Complete Picture of Stream Health

The Blue Water Task Force (BWTF) is a nonprofit watershed group located in Big Sky, Montana that has been running a successful volunteer water quality monitoring program since 2000. BWTF collects water chemistry data four times a year representing four distinct hydrologic/biologic regimes (winter baseflow, summer baseflow, high flow, pre-snowmelt). In addition, BWTF collects and analyze aquatic insects twice a year in April and September.

One of the most important lessons that we have learned from 10 years of data collection is that seasonal data collection can reveal water quality issues that may not be visible from just summer data collection alone. Understandably, summertime may be a more favorable time to be dipping your hands and feet into the stream. However, in the Upper Gallatin, we have discovered that you can sometimes tell a more complete story of watershed health from seasonal water quality collection.

One example is the nitrogen story. In the summer, nitrogen in terrestrial and aquatic ecosystems can readily be used for growth by vegetation and microbes resulting in low summer nitrogen concentrations. Therefore, during the summer, there is the potential for biological uptake of nitrogen to be masking elevated levels of nitrogen loading occurring in the watershed. Collecting nitrogen data during the winter, when biological utilization of nitrogen is at a minimum, may tell a more complete story of watershed health. Here in the Upper Gallatin watershed, BWTF has discovered some areas of concern from winter stream data collection that would not have been uncovered from just summer data collection alone. In some streams, nitrogen concentrations are very high during the winter, while concentrations are low during the summer. Thus, seasonal monitoring has alerted us to some local water quality problems that need to be addressed.

So start planning now. This winter get on a pair of snowshoes, take a ski pole for balance, and head for the stream for some winter streamwater collection. You could even combine water collection with a cross country ski trip if you are in for a real adventure!