Wastewater Lagoon Treatment & Water Resource Recovery

Treating wastewater with BioHaven Floating Island lagoon treatment systems can mean huge savings for the small community whose lagoons are not meeting discharge standards and are faced with an upgrade. Large treatment facilities can utilize BioHavens to polish their tertiary effluent and even harvest marketable products. Retrofitting with BioHavens is straightforward, non-disruptive and scalable.

  • Proven technology for lagoon treatment and tertiary polishing
  • Year-round biological removal of contaminants
  • Potential revenue opportunity from harvested biomass
  • Active and passive systems or a combination of both
  • Non-disruptive installation, nominal maintenance and low operator input
  • Specialized plants that target specific pollutants

How a BioHaven Floating Island Works in Wastewater Lagoon Treatment

BioHavens are a type of fixed-film treatment that employs bio-reactive processes in combination with plant remediation. The matrix provides an effective treatment surface as water is circulated through the fine mesh and begins to grow biofilm. Over time, as plant roots grow unimpeded through the permeable matrix, a massive surface area is created to accommodate the bacteria that consume organic matter and nutrients in wastewater. The exchange of sugars and enzymes between plants and microbes increases both microbial activity and plant growth to provide an unsurpassed water-cleaning approach.

The main function of floating islands in removing pollutants from effluents is:

  • Plant roots assisting in filtering and settling processes for P.
  • Plant roots acting as a large surface area for micro-organism activity in decomposition, nitrification, and denitrification (removal of BOD and N).
  • Mild acidification of water due to release of humic acids, and a C input from senescent vegetation; assisting denitrification.

What about sulfate and phosphorus removal?

Specific challenges, such as sulfate removal, can be effectively targeted with hyper-accumulator plants. The Forced-Flow StreamBed uses a high-capacity airlift blower to direct flow into submerged matrix to maximize the circulation (and retention) of warmer water through the matrix and to enable it to simulate a bioreactor. BioHavens up-cycle nutrients into biomass (plant or animal life) and harvesting is a simple process. Up-cycling phosphorus locally (i.e., recovering it from water) not only saves sensitive waters from algae blooms and taxa loss, but minimizes the footprint associated with mining and transporting phosphorus to grow such commodities elsewhere.

  • Features
    • BioHavens are enhanced for long life in a wastewater setting. Non-corrosive fixtures, tethering to external bollards and environmentally-safe coatings protect the system components.
    • Passive BioHavens planted with bushy-rooting perennials, maximize surface area and existing circulation patterns. Islands can be effectively deployed where power savings are desired. Specially-designed curtains can be installed to prevent short-circuiting.
    • BioHaven Forced-Flow StreamBeds, which use an efficient airlift blower, are ideal for cold-weather treatment where they are effective under ice and are designed to limit temperature loss.
    • Access walkways can be installed for plant maintenance on large systems to reduce O & M costs and facilitate harvesting.
    • BioHaven technology is an ideal platform for Water Resource Recovery (WRR), capitalizing on the ability of nutrients to grow into biomass that can be harvested and utilized beneficially.
    • Expected lifespan is 20 – 30 years.

  • Water Resource Recovery

    The future of Water Resource Recovery (WRR) is viewing the contaminants in wastewater as resources to be recovered rather than problems to be eliminated. In larger Water Resource Recovery Facilities (WRRFs), the end-products are typically various types of water re-use, phosphorus recovery and re-use (among other goals). BioHavens have a part to play in resource recovery, through growth and harvest of potentially beneficial plants or fish, that may have commercial or other value. Examples of this are:

    • Hyper-accumulator plants that take up selenium can be harvested and ground up to be added to selenium-poor soil or feedstock.
    • Minnows can be propagated using the biofilm, protozoa and macroinvertebrates present in BioHavens as food, then harvested and sold as bait fish.
    • Landscape trees and shrubs can be grown to a certain size using fertilizers (phosphorus) present in the water and harvested for re-use.
    • Resource Recovery Facilities can be used to grow breed stock for valuable native species, such as the eels harvested and released from a facility in New Zealand.

    The positive footprint associated with using phosphorus in situ, plus the potential of the actual harvest to offset initial installation costs, assures a role for BioHavens in the forward-thinking Water Resource Recovery environment.

  • Treatment Benefits

    The typical wastewater contaminants of concern can be treated by manipulating the BioHaven treatment processes, even at cold temperatures:

  • Case Studies and Research
    • Achieving Significant Nutrient Removal in Aerated Wastewater Lagoons using floating island technology

      a large circular pattern of floating islands positioned in a wastewater treatment lagoon

      Rehberg Ranch Residential Subdivision, Billings, Montana USA

      This case study demonstrates the abilities of Floating Islands to significantly reduce nutrient levels in aerated wastewater. With a coverage area of 6.4%, the treatment lagoon in its first season achieved significantly greater removal rates, in particular of Ammonia (38%) and Total Phosphorus (27%),

    • Moonlight Basin – excellent Nitrogen removal from wastewater at altitude

      a line of floating islands leading from one shore of a lake to the other

      Big Sky, Montana

      This stunning array of BioHavens, installed and planted by Watershed Consulting, out-performed the customer’s expectation with exceptional Nitrogen removal.

    • CH2M Hill study measuring nutrient removal by BioHaven technology in waste water

      a lake creature called a firebrat on a metal surface in shallow water

      Pasco, Florida

      This major study of the impact of 20 BioHaven floating islands demonstrated our highest removal rates so far on Nitrogen and Phosphorus, as well as documenting ancillary benefits of wildlife habit and mosquito abatement. The original research report is available on request from info@floatingislandinternational.com.

    • BioHaven Floating Islands technology enables this Louisiana wastewater facility to stay in compliance and win an EPA award in the process

      rows of growing floating islands that stretch from one shore of a pond to another

      Elayn Hunt Correctional Facility, St. Gabriel, Louisiana

      This Louisiana DEQ-funded project achieved the best nutrient uptake recorded to date in the US using BioHaven floating islands. During a seventeen-month period of monthly sampling, COD, ammonia and phosphate were reduced to consistently manageable levels to keep the facility in compliance.

    • Marton Waste Water Treatment: First-of-its-kind floating island “Lid” eliminates odor, reduces BOD and cuts annual operating costs

      a dirt road that makes a hairpin curve around a large section of floating island called a 'lid'

      Marton, New Zealand

      In this innovative application of a BioHaven floating island from New Zealand, a blanket or lid is built to cover and treat a pond anaerobically, thereby reducing troublesome odors which had until then plagued the residents of Marton. This treatment option was highly successful in improving the effluent, and saved the city approximately $150,000 in annual operating costs.

  • Related Articles

Wastewater Lagoon Treatment & Water Resource Recovery

rows of floating islands cover most of a lake that is lined with tall bare trees

aerial view of land - 1/3 is a lemon tree farm, 1/3 is wastewater ponds filled with floating islands, and 1/3 are buildings for processing lemons

a wastewater pond with floating islands running across the middle

floating island product illustrates the forced flow streambed


Cost savings through retrofitting

Since it can be retrofit to an existing asset, a BioHaven solution requires low capital investment compared to traditional mechanical systems. BioHaven solutions also have very low operating and maintenance costs.

Flexibility to fit your lagoon treatment needs

BioHavens can easily be adapted to suit a wide range of situations. They can:

  • Fit into any existing lagoon or polishing pond
  • Work within the energy limitations of the facility
  • Operate in cold climate or extreme environmental conditions
  • Be adjusted to manipulate specific treatment conditions
  • Be installed in stages to meet changing treatment requirements

We work directly with the client or with city engineers to design a tailored solution:

  • Utilizing a proprietary BioHaven-specific modeling tool, system sizing is optimized
  • Our engineers understand the resource recovery environment and remediation technologies
  • Installation and service contracts available.


Power of the People

The idea that small communities can operate sustainably energizes the FII team. Part of this energy comes from the people we serve, as they pick up on the vision of their community operating on such a holistic basis.  People just get it!  

Imagine that today, your village’s wastewater empties right into the local trout stream.  And no one talks about fishing for a mile or two downstream from town. There is a real solid reason for this.  But that’s today.  Tomorrow, you can send water by those trout that does them no harm.  People get this.  And when you show them a system that pays for itself in the process, they end up feeling really good about where they live.

What is Water Resource Recovery?

The concept of extracting valuable product from your wastewater facility. It means that the wastewater industry is now being purposeful about more than just making polluted water safe. Now there is serious direction around extracting value from this water. Here’s another way of saying this…”water needs to pay for itself.” If you live on a lake or own a pond, for example, the line might go…”grow fish instead of algae.”

Today with BioHavens you can also grow beautiful pollinator plants, or harvestable landscape trees. These trees are planted in islands as seedlings, then harvested to be replanted as valuable trees on shore once they reach a two inch caliper. In the meantime, they’ve been extracting pollution. And BioHavens are designed to be replanted, to repeat the cycle.

Letting Nature Do Her Work as Part of Lagoon Treatment

This can happen commercially on wastewater lagoons, or in a lake or pond. Bring unhealthy water systems back to health. What’s amazing is how easy this is. It’s as if all we do is turn nature loose! It’s as if all we have to do is “give” her permission!

How Big Does Your Wastewater Facility Need to be to Justify a BioHaven WRR System?

Extracting valuable product from large, concrete and steel wastewater facilities has been in the works for years now.  But not so with small lagoon based facilities, until right now.  BioHaven’s WRR system can operate in essentially any size lagoon facility.  Are there economies of scale that argue for large lagoons?  Not necessarily.  Let’s say your system is handling just 40,000 gallons per day, which would make you a village of about 500 people, based on the 80 gallon per day per person number we typically use to estimate wastewater volume.  You might have a three lagoon system, with each cell essentially the best part of one acre.  

In such a setting our system would target operating on the third lagoon.  We might cover two thirds, or perhaps the whole lagoon, with BioHavens.  Generate local energy with solar BioHavens. You could even plant and harvest valuable crops on top of the island, or grow fathead minnows underneath.  This relatively small wastewater system can pay for itself in a reasonable time frame.  

It’s difficult for public officials to justify spending the volume of money needed to fix water, in the face of so many other pressing demands for that money. If we are really going to fix water, the water resource recovery system should

  •  Generate Revenue sufficient to show a reasonable ROI.
  •  Be aesthetically pleasing.
  •  And do this without creating a large O&M burden.