Floating Wetland Islands: A Sustainable Solution for Lake Management

Nick Decker, PA State Parks Resource Manager, and Cory Speroff and Katie Walston of Princeton Hydro position a floating island of native plants in the lake at Frances Slocum State Park

Looking for a unique and creative way to manage nutrient runoff in freshwater lakes? Installing Floating Wetland Islands (FWI) is a low-cost, effective green infrastructure solution used to mitigate phosporus and nitrogen stormwater pollution often emanating from highly developed communities and/or argricultural lands.

FWIs are designed to mimic natural wetlands in a sustainable, efficient, and powerful way. They improve water quality by assimilating and removing excess nutrients that could fuel algae growth; provide valuable ecological habitat for a variety of beneficial species; help mitigate wave and wind erosion impacts; provide an aesthetic element; and add significant biodiversity enhancement within open freshwater environments.

“A pound of phosphorus can produce 1,100 lbs of algae each year. And, each 250-square foot island can remove 10 lbs of phosphorus annually.” explains Princeton Hydro Staff Scientist Katie Walston. “So, that’s 11,000 lbs of algae that is mitigated each year from each 250 square foot of FWI installed!”

This illustration, created by Staff Scientist Ivy Babson, conveys the functionality of a Floating Wetland Island

This illustration, created by Staff Scientist Ivy Babson, conveys the functionality of a Floating Wetland Island

Typically, FWIs consist of a constructed floating mat with vegetation planted directly into the material. Once the islands are anchored in the lake, the plants thrive and grow, extending their root systems through the mat and absorbing and removing excess nutrients from the water column such as phosphorus and nitrogen.

Native plants on the floating island designed by Princeton Hydro that will help reduce the phosphers and algae in the lake at Frances Slocum State ParkThe plants uptake a lot of nutrients, but the workhorse of the FWIs is the microbial community. The matrix used within the islands has a very high surface area and it promotes microbial growth, which performs the majority of the nutrient uptake. Additionally, the root growth from the plants continues to increase the surface area for the microbial biofilm to grow on. Both the plants and microbes acting together help optimize nutrient removal.

Princeton Hydro has designed and installed numerous FWIs in waterbodies large and small for the purpose of harmful algal bloom control, fisheries enhancement, stormwater management, shoreline preservation, wastewater treatment, and more. FWIs are also highly adaptable and can be sized, configured, and planted to fit the needs of nearly any lake, pond, or reservoir.

Greenwood Lake

Recently, the Princeton Hydro team completed a FWI installation in Belcher’s Creek, the main tributary of Greenwood Lake. The lake, a 1,920-acre waterbody located in  both Passaic County, New Jersey and Orange County, New York, is a highly valued ecological and recreational resource for both states and has a substantial impact on the local economies. In addition, the lake serves as a headwater supply of potable water that flows to the Monksville Reservoir and eventually into the Wanaque Reservoir, where it supplies over 3 million people and thousands of businesses with drinking water. 

Since the lake was negatively impacted by HABs during the 2019 summer season, Greenwood Lake Commission (GWLC) has made a stronger effort to eliminate HABs and any factors that contribute to cyanobacteria blooms for 2020 and into the future. Factors being addressed include pollutant loading in the watershed, especially that of Belcher’s Creek. The installation of FWIs in Belcher’s Creek will immediately address nutrients in the water before it enters Greenwood Lake and help decrease total phosphorus loading. In turn this will help reduce HABs, improve water quality throughout the Greenwood Lake watershed, and create important habitat for beneficial aquatic, insect, bird and wildlife species.

“In addition to the direct environmental benefits of FWIs, the planting events themselves, which involve individuals from the local lake communities, have long-lasting positive impacts,” said Dr. Jack Szczepanski, Princeton Hydro Senior Project Manager, Aquatics Resources. “When community members come together to help plant FWIs, it gives them a deepened sense of ownership and strengthens their connection to the lake. This, in turn, encourages continued stewardship of the watershed and creates a broader awareness of how human behaviors impact the lake and its water quality. And, real water quality improvements begin at the watershed level with how people treat their land.”

The project was partially funded by the New Jersey Department of Environmental Protection’s (NJDEP) Water Quality Restoration Grants for Nonpoint Source Pollution Program under Section 319(h) of the federal Clean Water Act. As part of the statewide HAB response strategy, the NJDEP made $13.5 million in funding available for local projects that improve water quality and help prevent, mitigate and manage HABs in the state’s lakes and ponds. The GWLC was awarded one of the NJDEPs matching grants, which provided $2 in funding for every $1 invested by the grant applicant. For this project, the GWLC purchased the FWIs and NJDEP provided the 2:1 cash match in order for the GWLC to implement additional HAB prevention and mitigation strategies in critical locations throughout the watershed.

Check out the photos from last month’s installation:

Here are a few more examples of FWI design and installation projects we’ve completed:

Frances Slocum Lake

Officials with the state Department of Conservation and Natural Resources, Luzerne Conservation District, Nanticoke Conservation Club, and students at Rock Solid Academy in Shavertown teamed up with Princeton Hydro to install two floating islands on the lake. They were planted natives to the area, including Green Bulrush, Broadleaf Arrowhead, Blue Flag Iris, Shallow Sedge, and Spotted Joe-Pye.

Princeton Hydro also installed solar-powered aeration systems in the middle of the FWIs. Aeration systems provide additional water quality improvements, help prevent water around the islands from stratifying, promotes “through-column” mixing, and helps to minimize the occurrence of phytoplankton blooms. The use of solar-powered aeration, whether installed on a FWI or along the shoreline, creates a sustainable, cost-effective, zero-energy water treatment solution, and eliminates the need to run direct-wired electrical lines to remote locations. Learn more.

Princeton Hydro also installs solar-powered aeration systems on FWIs, creating a sustainable, cost-effective, holistic water treatment solution.
Harveys Lake

Princeton Hydro, along with project partners, installed five floating wetland islands in Harveys Lake in order to assimilate and reduce nutrients already in the lake. The islands were placed in areas with high concentrations of nutrients, placed 50 feet from the shoreline and tethered in place with steel cables and anchored. A 250-square-foot FWI is estimated to remove up to 10 pounds of nutrients per year, which is significant when it comes to algae. Learn more.

Volunteers install native plants in one of the FWIs installed in Harveys Lake. Photo by: Mark Moran, The Citizen’s Voice.
lake hopatcong

Through a nonpoint source pollution grant awarded by NJDEP to the Lake Hopatcong Commission, Jefferson Township was able to install FWIs in order to deliver better water quality to Ashley Cove and Lake Hopatcong. The primary goal of the project was to reduce high levels of algae-causing phosphorus present in the lake. In each FWI, indigenous plants, Milkweed and Hibiscus, among other vegetation, were planted along with peat and mulch. Learn more.

Casey Hurt, right, and Richard Ampomah maneuver one of two floating wetland islands in Ashley Cove.
Lake Holiday

Two interconnected sets of FWIs were installed in Lake Holiday in the tributary coves of Isaac’s and Yeider’s Creeks. The strategic placement of the islands eliminates interference with normal boat traffic. In order to minimize movement, the FWIs were secured to trees along the bank with coated cable and protective bands and anchored to the lake bottom with submerged concrete blocks. Learn more.

Senior Scientist Katie Walston installs goose netting around the vegetation in order to prevent geese and other unwanted species from feeding on the plants.

Over the coming weeks, our team will be in Asbury Park, New Jersey installing FWIs in Sunset Lake. Stay tuned for more! For additional information about floating wetland islands and water quality management, go here: bit.ly/pondlake.

Conservation Spotlight: Reducing Flood Risk and Restoring Wetlands in Jamaica Bay

Located in Queens, New York on the northern shore of Jamaica Bay, Spring Creek South contains approximately 237 acres of undeveloped land, including wetlands and 2.4 miles of coastline. The site is bounded by the Howard Beach residential neighborhood in Queens, a commercial area along Cross Bay Boulevard, the Belt Parkway, and Jamaica Bay. The northwest section of Spring Creek South is part of the National Park Service’s Gateway National Recreation Area, and is largely comprised of small patches of degraded tidal marsh and disturbed and degraded upland ecosystems.

On October 29, 2012, Hurricane Sandy drove a catastrophic storm surge into the New Jersey and New York coastlines. Spring Creek South and the surrounding community of Howard Beach experienced record flooding and damage to property and critical infrastructure. Storm tides caused damage and erosion along the shoreline and in the salt marsh area, degrading important habitat and leaving the site vulnerable to invasive species.

Hurricane Sandy Aftermath at Howard Beach, taken 10/30/2012 by Pam Andrade

The New York State Division of Homeland Security and Emergency Services (NYSDHSES) was awarded funding from FEMA’s Hazard Mitigation Grant Program to restore Spring Creek South. The U.S. Army Corps of Engineers (USACE) New York District, serving as project administrator, contracted Princeton Hydro to provide ecosystem restoration services. The goal of the project is to reduce future flood risk exposure while also protecting, restoring, and improving the quality and function of ecological systems; improving stormwater management and water quality; and enhancing the park’s visitor experience.

To achieve this goal, the project team is using an integrated approach that involves utilizing green infrastructure to create a natural barrier for the community and reduce the risks of coastal storms. Project activities include berm construction and the restoration of tidal marsh, creation of freshwater wetland forest, and creation of maritime shrub, forest, and grassland habitats, as well as stabilization of the existing shoreline.

On December 31, 2018, we completed Phase One of the project, which entails engineering design and preliminary permitting. More specifically, we’ve provided conceptual planning; analysis of subsurface soils for geotechnical properties and hazardous waste; coastal and freshwater wetland delineations; biological benchmarking analysis; and the development of sea level rise curves and two-dimensional hydrologic and hydraulic coastal modeling. As part of the hydrology study, we analyzed what the site could be expected to look like in 50 years due to climate changes and sea level rise. Our engineering design was also brought to 65% completion.

We also obtained permits, prepared the Environmental Assessment (EA), and oversaw the National Environmental Policy Act (NEPA) process. The EA received a “Finding of No Significant Impact” (FONSI) from FEMA, which means the environmental analysis and interagency review concluded that the project has no significant impacts on the quality of the environment.

Due to the complex nature of this project and its location, we are coordinating with a variety of different entities, including the local Howard Beach Community Board, the FAA (proximity to JFK International Airport), Port Authority, USACE, NOAA Fisheries, USFWS, USEPA, NYSDEC, NYC DEP, the National Park Service, HDR Engineering and WSP Engineering.

Phase Two of the project is the construction phase, which is expected to take about two years to complete. A key part of the Spring Creek South construction activities is the restoration of approximately 40 acres of tidal marsh, which is anticipated to improve water quality locally by stabilizing sediment, reducing erosion, and filtering dissolved particulate materials. The project team will restore existing coastline areas and install a salt marsh along the shoreline. Planted with native flora, like Spartina alterniflora, a perennial deciduous grass found in intertidal wetlands, the coastal salt marsh will help to stabilize sediment. Additionally, removing invasive species like Phragmites australis from the area and replacing it with native plant species will increase the ability for native vegetation to colonize the site, improve vegetative diversity, and reduce fire risk in the park.

A forested wetland area and berm will also be created in order to provide the surrounding communities with natural shields and buffers to future storms. The berm, with an elevation of 19 feet (NAVD88), will help to manage the risk of storm surge flooding caused by coastal storms. The forested wetland area will also provide improved stormwater runoff storage, naturally filter stormwater, and, via flap gates, direct its flow toward Jamaica Bay, away from residential and commercial properties.

These measures will help to dissipate wind and wave energy, increase shoreline resilience, improve stormwater management at the site, and create habitat that increases the ecological value and biodiversity at the site, while providing resilience benefits. Restoration activities will benefit vulnerable and rare ecological communities by producing localized environmental enhancements, including improving water quality and creating and restoring habitat. The project also increases opportunities for recreational uses such as wildlife viewing/photography, fishing, and nature study.

Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of wetland rehabilitation projects. To learn more about some of our ecosystem restoration and enhancement services, visit: bit.ly/PHwetland.

 

Mitigation Milestone Reached at Mattawoman Creek Mitigation Site

Photo courtesy of GreenVest

Mattawoman Creek Mitigation Project will Restore and Protect 80+ Acres of Mattawoman Creek, Chesapeake Bay’s Most Productive Tributary

As one of the Chesapeake Bay’s most productive tributaries and a vital part of Maryland’s natural resources, Mattawoman Creek supports some of the largest populations of finfish, amphibians, and birds in the state. A collaborative team of private and public sector entities have designed the “Mattawoman Creek Mitigation Site” in Pomfret, Charles County, Maryland, an effort that will enhance or create 64+ acres of wetlands and restore nearly 3,800 linear feet of this perennial stream.  With over 28,500 native trees and shrubs to be planted, this mitigation project will result in 80+ acres of continuous, forested wetland with complex and diverse vegetative communities. It is expected to provide a wide array of habitat to resident and transient wildlife, including birds, reptiles, invertebrates, amphibians and rare, threatened and endangered species.

Unique to this project, Mattawoman Creek Mitigation Site is Maryland’s first-ever Umbrella Mitigation Banking Instrument (UMBI) for federal and other government agency use.   A UMBI is the bundling of multiple mitigation banks into one agreement in order to streamline the regulatory approval process, thereby eliminating steps and involving fewer resources. The Maryland UMBI document helps the USAF and other public agencies secure certainty of cost and schedule, facilitate timely permit issuance, and expedite the satisfaction of their permitted requirements for planned capital improvement projects. This approach also maximizes the scale of restoration and resulting land protection and efforts, creating contiguous blocks of habitat with greatly enhanced benefits compared to single, permittee-responsible projects. This precedent was a result of a partnership between United States Air Force (USAF) and Joint Base Andrews (JBA), U.S. Army Corps of Engineers (USACE), Maryland Department of the Environment (MDE), GreenTrust Alliance, GreenVest, and Princeton Hydro.

Projects completed under the UMBI will reduce federal and state workload expediting the regulatory review and issuance of permits by the MDE and USACE. Additionally, projects completed under this UMBI will aid in compliance with the Federal Paperwork Reduction Act where federal regulatory staff can evaluate success and performance issues for multiple permittees at one single habitat restoration or mitigation site. In addition, federal costs are capped, and liabilities  are transferred through to GreenVest, the private sector operator, and GreenTrust Alliance, the nonprofit bank sponsor, who will also serve as the long-term steward of sites restored under this program.

Pictured is the southern restoration area after
sorghum germination, prior to wetland creation
and reestablishment.
A function-based stream assessment was
performed on the degraded channel.

 

Photo courtesy of GreenVestDesign, engineering/modeling, and permitting of the site was completed by  Princeton Hydro and GreenVest under our currently Ecosystem Restoration contract with the USACE. Princeton Hydro also provided an Environmental Assessment and Environmental Baseline Survey, and conducted a geotechnical investigation, which included the advancement of test pits, visual and manual investigation techniques and logging, infiltration testing, laboratory soils testing, and seasonal high-water table estimations.

A wetland water budget was also developed for the proposed wetland creation and restoration to determine if sufficient water is available to establish or reestablish wetlands on the site. It was also used to inform design development including proposed grading and plant community composition. The establishment and re-establishment of wetlands on the site will be accomplished through directed grading, ditch plugging and stream restoration designed to maximize the retention of surface water, floodplain re-connection, and groundwater inputs.

Highlights from the Mattawoman Creek Wetland and Stream Mitigation project:
  • 80 acres of land were placed into conservation easement and removed from active row crop production and cattle pasture. The easement, which is held by GreenTrust Alliance, provides permanent protection for all 80 acres.
  • Over 64 acres of wetlands will be restored, created, enhanced or preserved, which will sequester approximately 75 tons of carbon per year.
  • 3,798 linear feet of perennial stream will be restored by re-establishing, historic floodplain access during more frequent storm events, stabilizing hydraulics and geomorphology, and adding aquatic habitat value.
  • Full integration of the wetland and stream restoration elements will occur exponentially, increasing anticipated functions and values in the post construction condition. Functions include: storm damage and flood attenuation, groundwater recharge and discharge, nutrient cycling and sequestration, local water quality improvement, and wildlife habitat enhancements.
  • This project will also create and enhance the forested wetland and stream habitat for the State-listed Threatened Selys’ Sundragon (Helocordulia selysii).
  • As part of the site design, over 28,500 native trees and shrubs will be planted.
  • The Mattawoman Creek Mitigation Site is located within a Tier 3 Biodiversity Conservation Network area. These areas are classified by the Department of Natural Resources as “highly significant for biodiversity conservation” and are priority conservation areas that support critical species and habitats.
  • The project will yield advanced mitigation values: 7.913 in wetland credits and 1,595 in stream credits. These credits are durable and will be available for JBA’s use in order to satisfy permitted impacts associated with planned capital improvement projects.

Over 6,000 acres (25%) of the Mattawoman Creek watershed has been protected by public ownership and various conservation and agricultural easements, which, in addition to the Mattawoman Creek Mitigation Site, help ensure that Mattawoman Creek forever remains a high-quality destination for outdoor recreation.

Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of tidal and freshwater wetland rehabilitation projects. To learn more about our wetland restoration, creation, and enhancement services, visit: http://bit.ly/PHwetland

Teaching NYC High Schoolers About Wetlands

Ms. Hannah Goldstein and her Environmental Science students at Franklin Delano Roosevelt High School in Brooklyn, NY welcomed Emily Bjorhus, Princeton Hydro Environmental Scientist, to be a guest speaker on the topic of wetlands. The students, 10th, 11th, and 12th graders, learned what defines a wetland, how wetlands function, and why wetland ecosystems are important to our communities. Emily also taught the students how to identify wetlands in the field.

The presentation also involved hands-on instruction, which included a trip outside to the school courtyard where students learned how to collect soil samples using an auger and how to determine if hydric soils are present. To identify surrounding trees, students used a dichotomous key, a tool that allows users to make a series of choices based on characteristics such as leaf and fruit shape. Using the skills and information they learned, Emily helped each classroom determine whether a wetland was present. As it turns out, the courtyard in the middle of Franklin Delano Roosevelt High School does not contain a wetland!

“Science is such an important subject matter for kids to be learning for a variety of reasons. Environmental science education in particular encourages thought patterns, which get kids engaged in real-world environmental protection activities,”  said Emily. “I really enjoyed working with Ms. Goldstein and her students. I hope my presentation inspires the students to learn more about wetlands and become ambassadors of wetland conservation.”

To learn more about Princeton Hydro’s tidal and freshwater wetland services, visit: bit.ly/PHwetland

Improving Water Quality & Reducing Habitat Loss with Floating Wetland Islands

Floating Wetland Islands (FWI), also known as floating treatment wetlands, are an effective alternative to large, watershed-based, natural wetlands. Often described as self-sustaining, FWIs provide numerous ecological benefits. They assimilate and remove excess nutrients that could fuel algae growth; provide habitat for fish and other aquatic organisms; help mitigate wave and wind erosion impacts; provide an aesthetic element; and can be part of a holistic lake/pond management strategy. FWIs are also highly adaptable and can be sized, configured and planted to fit the needs of nearly any lakepond or reservoir.

Princeton Hydro Senior Scientist Katie Walston recently completed the Floating Island International (FII) Floating Wetland Master Seminar. The seminar provided participants with an in-depth look at the various technologies and products FII offers. Through hands-on examples, course participants learned how to utilize wetland islands for fisheries enhancement, stormwater management, shoreline preservation, wastewater treatment and more.

“The Master Seminar was truly valuable both personally and professionally,” said Katie. “I learned a tremendous amount and thoroughly enjoyed the experience. It’s very fulfilling knowing that I can take the knowledge I’ve learned back to Princeton Hydro and make positive impacts for our clients.”

FII was launched by inventor and outdoorsman Bruce Kania who was driven by the desire to reverse the decline of wetland habitats by developing a new and natural stewardship tool that could clean water and, in the process, improve life for all living creatures. He found that the answer lies in Biomimicry: duplicating nature’s processes in a sustainable, efficient and powerful way to achieve impeccable environmental stewardship for the benefit of all life.

Bruce brought together a team of engineers and plant specialists and created BioHaven® floating islands. These islands biomimic natural floating islands to create a “concentrated” wetland effect. Independent laboratory tests show removal rates far in excess of previously published data: 20 times more nitrate, 10 times more phosphate and 11 times more ammonia, using unplanted islands. They are also extremely effective at reducing total suspended solids and dissolved organic carbon in waterways.

Due to population growth, industrialization and climate change, wetlands are at risk of rapidly declining in quantity and quality due. However, every floating wetland island launched by FII provides an effective strategy for mitigating and adapting to the impacts of over development and climate change.

The unique design of BioHaven® floating islands means that 250 square feet of island translates to an acre’s worth of wetland surface area. These versatile floating islands can be launched in either shallow or deep water, and can be securely anchored or tethered to ensure that they remain in a specific location. They are almost infinitely customizable, and can be configured in a variety of ways.

In addition to ongoing prototype development, FII offers licensing opportunities to businesses and production facilities worldwide. FII continues to research and develop collaborative pilot projects to quantify BioHaven® floating islands’ efficacy.

Many thanks to Bruce and Anne Kania for hosting the Floating Wetland Master Seminar and inspiring action through their knowledge, passion and ongoing endeavors.

 

NJ Audubon undertakes $470G study of climate change impact on wetlands

Princeton Hydro is proud to be a partner on this incredible project

If you’ve ever gone birdwatching at any east coast wildlife refuge, then you probably understand the value of coastal impoundments. These man-made wetland habitats are contained by embankments and have gates that allow managers to manipulate water levels. In addition to being valuable, these structures are also very vulnerable to sea level rise and extreme weather.

Through a $470,000 federal grant, the New Jersey Audubon is implementing an initiative to study the vulnerability of these impoundments to climate change induced environmental impacts. Funded by the U.S. Department of the Interior via the National Fish and Wildlife Foundation, the Coastal Impoundment Vulnerability and Resilience Project (CIVRP) aims to map and catalog all state, federal, and privately owned coastal impoundments from Virginia to Maine. The project is a cooperative effort of a diverse team of partners including researchers from New Jersey Audubon, National Wildlife Federation, Conservation Management Institute (Virginia Tech), U.S. Fish and Wildlife Service and Princeton Hydro.

The CIVRP will ultimately reduce climate vulnerability and enhance the natural ecosystem function of these precious and treasured wetland habitats. Read the full article from MyCentralJersey.

Princeton Hydro specializes in the restoration, creation and enhancement of tidal and freshwater wetlands. Contact us to learn more, and read about some of our award-winning wetland-related projects here.