University of Maryland

College of Agriculture & Natural Resources

Environmental Science & Technology

Floating Islands – Own One Today

A half-acre pond with poor water quality treated with 300-square-feet of floating island is capable of removing 183 pounds of nitrogen and 25 pounds of phosphorus per year, and would cost around $10,000.

Owning an island is easier than you might think, that is–a floating island. This man-made ecosystem mimics naturally occurring wetlands and has the ability to clean water while providing the same ecological benefits as natural wetlands. Dr. Joshua McGrath, assistant professor at ENST and alumnus Kevin Hedge are exploring the nutrient removal effectiveness of floating islands in poultry stormwater ponds on the Eastern Shore of Maryland.

The restoration of lost wetlands is an important focus of today’s land and water stewardship, as wetlands are the most valued and complex habitats on earth. Their progressive loss has contributed to a sharp decline in numerous bird species and vertebrate animals such as toads, frogs, caecilians, and salamanders. Constructed of post-consumer polymer fibers and vegetated with native plants, floating islands have the ability of natural wetlands to clean waterways. Pilot projects with floating islands are currently underway in the Baltimore’s Inner Harbor, the Chesapeake Bay, and several Eastern Shore poultry farms. To help study the effects of these islands, the Maryland Industrial Partnerships Program, an initiative of the Maryland Technology Enterprise Institute at the University of Maryland, has awarded $139,000 to BlueWing Company and Dr. McGrath for developing BioHaven Floating Islands.

Floating Islands And Clean Water
Floating islands have the potential to be deployed in virtually all of the impaired waters, including the Chesapeake Bay. “Taking advantage of naturally occurring biological processes allows for the creation of a cost effective and low maintenance solution to boost nutrient removal and environmental remediation,” explains Dr. McGrath. Last summer, he lead a group of researchers to measure the nutrient removal capacity of floating islands in stormwater contaminated ponds on two Eastern Shore poultry farms–Church Hill and Federalsburg. These studies are currently underway and results are expected in the next few months. “If these affirm previous findings, the results will be used to estimate the efficiency of artificial wetlands so that they can be included in various cost-share mechanisms and tools such as the Chesapeake Bay Model,” says Dr. McGrath.

Effectiveness And Cost
As the need to reduce nutrient levels in wastewater is becoming increasingly critical, floating islands are the new cutting-edge wetland technology. “Using a nature-inspired system to clean water could truly be revolutionary on a global scale,” says Kevin Hedge, ENST alumnus and managing partner of BlueWing Environmental. Hedge estimates that a half-acre pond with poor water quality treated with 300-square-feet of floating island is capable of removing 183 pounds of nitrogen and 25 pounds of phosphorus per year, and would cost around $10,000. “Floating islands will become more effective with time as more natural surface areas like plant roots colonize and cover the island matrix,” concludes Hedge.

Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2014.