Flathead Lake water and weather monitoring buoys in dry dock

Mar 26, 2014

One of two data gathering buoys the Flathead Lake Biological Station has been operating since August of 2011.
Credit Katrin Frye

Two large, yellow buoys with “Flathead Lake Biological Station” stenciled on the side now sit on the shore beside the lake they’ve been collecting data on since August of 2011. These weather buoys were also measuring water quality and temperature, among other things.

The buoys were taken in to calibrate the instruments and replace the batteries.

One went in towards the middle of the lake, off shore from Yellow Bay, the other, farther north, mid-lake off the shore of Woods Bay. Dr. Bonnie Ellis of the Biological Station said the buoys were designed by the Woods Hole Oceanographic Institution.

Below the buoys an underwater profiler traveled up and down the cable anchoring them in place gathering water quality information including temperature, the amount of algae in the water, and dissolved oxygen. Ellis said the information gathered goes into their water quality model to help better predict how the lake will react to different variables.

“We will be able to ask questions of the model like; how increasing temperatures will effect algal pigments in Flathead Lake, will they cause algal pigments to increase or decrease, and by using data from the profiler, we can determine how accurate this model is,” Ellis said.

A National Science Foundation grant funded the initial project.

Research Scientist Tom Bansak said the buoys are part of a larger weather station effort.

The Biological Station has monitoring sites around the lake, and teams go out by boat periodically to collect data, but the buoys provided a steady stream of weather and water quality measurements.

“I would say that the most interesting thing is how variable it is around the lake; it can be raining in Yellow Bay, and sunny over in Rollins, and the winds can be coming from completely different directions, and having that wind data from the water’s surface proved invaluable,” Bansak said.

Scientists Tom Bansak and Dr. Bonnie Ellis with the Flathead Lake Biological Station in Yellow Bay.
Credit Katrin Frye

Ells said it’s expensive to get the buoys back in the water. To give a feel for some of the costs involved she says calibrating the underwater sensors costs about $16,000, calibration of the surface sensors about $9,000, and more than $10,000 to $13,000 for the satellite linkup.

“Everyone wants the buoys to go back in the lake, including us, especially us, but we’re going to have to look closely at those costs,” Ellis said.

The Biological Station hopes to redeploy the buoys this summer.