Nutrient Sponges Help Clear Phosphorous Out of Hayden Lake


As many Idaho waterfront communities wrestle with nutrient overloads in their waterways, a few homeowners on the shores of Hayden Lake have devised an innovative way to sop up algae-friendly phosphorous: floating nutrient sponges.

The Spokesman-Review reports that a Hayden Lake homeowners association is combating murky water and algae with floating gardens filled with nutrient-hungry plants like water sedges, monkey flowers and grasses.

As the plants' roots reach towards the lake bed, they leach chemicals like nitrogen and phosphorous from the water and silt, competing with the algae that feed on those same nutrients, degrading Hayden Lake's water quality.

“They’re basically growing like hydroponics,” Karen Hayes, member of the Kootenai Environmental Alliance’s Hayden Lake Project, told The Spokesman-Review.

So far the KEA has purchased two floating wetlands, each 70 square feet in size, from Montana-based Floating Island International, for about $70 per square foot.