Floating Islands for Wastewater & Stormwater Management

BioHaven floating islands can treat organic carbon and suspended solids better than traditional methods - and for a fraction of the cost.

Conventional technology can get the job done, but only at a very high cost. Estimates, generated by consultants, are that Montana municipalities would have to spend between $800,000,000.00 to one billion dollars to achieve compliance over the next seven to ten years, relying on existing technology.

However, floating islands are a viable, cost-effective alternative. As our islands prove successful and achieve pollution uptake numbers in the field, we are confident we will be able to reduce these costs by 75%!


* Superior performance to constructed wetlands
* A viable solution to pollution
* Very affordable

A "Concentrated wetland effect"

BioHaven floating treatment wetlands (FTWs) cleanse water of the major pollutants commonly found in groundwater. They remove nitrates, ammonia and phosphates at a level comparable to engineered solutions, but unlike other systems, they do so at the same time. They are also effective at removal of heavy metals, such as zinc and copper, when present in the water column as suspended solids.

Their removal of suspended solids and BOD is extremely impressive.

Typically, after wastewater has passed through treatment facilities, there is still a high level of Phosphate present, which is finding its way into our major waterways and contributing to pollution and even dead zones in the ocean. In the new regulatory environment, levels of Phosphate must be drastically reduced.

Constructed wetlands have proven themselves to be an effective, natural way of removing pollutants, but they have some disadvantages. More recently, Floating Treatment Wetlands have come on the scene, improving performance and reducing the drawbacks. Research shows that, of these, by far the most successful are BioHavens, out-performing the next best by 2000%. They have additional advantages: they take up no land; they keep pace with water level fluctuations; and they work in both shallow and deep water.

BioHaven floating islands act as floating treatment wetlands, only more so. They provide a concentrated wetland effect.

BioHaven FTWs are constructed from a non-woven matrix made of recycled plastic, and injected with foam for initial buoyancy. Thousands of square inches of tiny matrix fibers (left) provide an expanded surface area for microbes to colonize - aerobic microbes which consume phosphates and ammonia, and anaerobic microbes which convert nitrates to harmless atmospheric gas. Once the BioHaven is launched, biofilm begins to grow inside and around it (biofilm = microbes). As water circulates through and across the island, the biofilm gets to work on the pollutants. The more the surface area, the more biofilm forms, and the more nutrients are removed. Inexpensive solar- and wind-driven pumps can assist water re-circulation. A limited amount of aeration is necessary to support phosphate removal.

Stormwater ponds experience similar problems with pollutants, and are often challenged by heavy metals such as zinc and copper, which are too fine to be filtered mechanically. Suspended particles attach to the biofilm and the roots of plants growing through the matrix. Eventually they slough off and fall to the sediment where they remain sequestered as long as anaerobic conditions are maintained.

BioHavens are eminently suitable for both wastewater and stormwater "polishing". Floating islands deployed in a wastewater treatment setting should be resilient to fluctuations in water quality influent. Some research even suggests they may help to lower operating costs because of the optimal way they utilize oxygen.

With BioHaven FTWs, though, you get more than a water polisher - you steward your waterway with a beautiful natural system and provide habitat for a myriad life forms in the process. BioHavens can be made to any shape or any size, can be "off the shelf" or custom built.

Easy to manage 4 foot by 8 foot floating island modules can be attached to form extremely efficient filtration systems to reduce suspended materials, reduce phosphates and nitrates, and help sequester carbon. This diagram shows possible ways of retrofitting a given surface area of floating treatment wetland into the wet pond stormwater treatment system recommended in ARC TP10.