Water Cleaning Islands
In Oak Creek, a suburb of Milwaukee, Wisconsin, three small islands in a pond are helping to treat stormwater. The islands are constructed of recycled plastic wrapped in coir, tethered to the bottom of a stormwater retention pond and covered with native plants.
plants’ roots pull some nitrogen, phosphorous and other suspended
solids from the pond directly, but only five percent of the island’s
nutrient uptake is done by the plants themselves. The islands are
designed to be ideal platforms for growing a layer of microbes and
bacteria, called a biofilm. This digests many more nutrients, and mimics
the action of a natural bog or wetland.