Water Quality Monitoring

PROTECT OUR WATERS>OTHER RESEARCH>WATER QUALITY MONITORING

ESLA is involved in various efforts to monitor water quality and change over time.

In 2023, ESLA acquired the necessary thin mesh netting to conduct plankton surveys on our Elk and Skegemog lakes. Plankton is critical to the sustenance of all life in our waters. A major concern is that the prevalence of quagga mussels, which voraciously feed on phytoplankton (plants), has impacted the food chain in ways that have compromised desired fish species, especially whitefish and trout species. The tests will be conducted annually for at least the next few years. The research is being conducted by ESLA’s biologist Samantha Ogle and ESLA board member and “Fish Guy,” Ken Krentz.

For more than 20 years, ESLA also has worked with the Volunteer Lake Monitoring Program sponsored by Tip of the Mitt Watershed Council. Volunteers, including three from ESLA who focus on ESLA waters, monitor 35 lakes in northwestern Michigan. The project helps provide valuable information to help protect and improve water quality in the lakes. Starting in May or early June, the monitors begin weekly visits to the deepest part of the lakes to perform water testing. After anchoring the boat, the monitors measure water clarity using a Secchi disc. The weighted disc is eight inches in diameter and painted black and white in alternating quarters. The volunteer slowly lowers the disc over the shaded side of the boat and notes the depth where it disappears. The disc is lowered an additional two feet and then slowly raised until coming back into view. After noting the depth of reappearance, the average of the two depths is calculated and recorded. The deeper the Secchi disc depth, the clearer the water.

Every other week, the volunteers collect a water sample to measure chlorophyll-a concentrations. Measuring the amount of chlorophyll-a in a water sample provides a fairly accurate estimate of the amount of algae, which includes phytoplankton and zooplankton, in the water. After determining the Secchi disc depth, the monitor collects the water sample in the same location. The water is filtered and the filtrate is stored in a freezer until the end of the season. All samples are then delivered to Tip of the Mitt and analyzed. A low level of chlorophyll-a indicates relatively low algae abundance and good to excellent water quality, while a high level of chlorophyll-a indicates dense algae growth and generally poor water quality. Data collected in the Volunteer Lake Monitoring Program has been entered into a comprehensive database.

Tip of the Mitt suggested in 2022 that ESLA add Phosphorus sampling to our volunteer monitoring plan. Other lakes in the Elk River Chain of Lakes have conducted this more frequent testing of phosphorus. We currently had been testing for phosphorus every three years as a part of the Comprehensive Water Quality Monitoring Program. Although we have not seen a poor trend in the phosphorus levels in our lakes, it is a good indicator for all lake water. Phosphorus is the nutrient most responsible for the pollution and premature aging of lakes in northern Michigan. The source of Phosphorus is mainly due to surface water run-off and atmospheric deposition.

The Comprehensive Water Quality Monitoring Program referenced above, is available to members of Tip of the Mitt Watershed Council. The Tip of the Mitt program monitors water quality parameters for 58 lakes and rivers, every three years.  Typically, data for temperature, dissolved oxygen, pH, conductivity, clarity, total phosphorus, total nitrogen, nitrate-nitrogen, and chloride, are collected at the surface, middle and bottom of the water column in each body of water. This data has been compiled into a single database and is available to the general public through Tip of the Mitt’s website or the MiCorps database. https://data.micorps.net/view/stream/