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The project was funded by Skylands Guardian, a nonprofit organization dedicated to protecting the natural resources of New Jersey's Highlands region through education, advocacy, and environmental stewardship. In partnership with Skylands Guardian, Princeton Hydro Aquatic Ecologist Katie Walston-Frederick led the hands-on installation event, which transformed native plants and recycled materials into living ecosystems designed to benefit the lake for years to come. A Nature-Based Solution for Cupsaw Lake Nestled within the Ramapo Mountains, Cupsaw Lake is a 65-acre freshwater lake in the heart of Ringwood Township. To help preserve its long-term ecological health, local partners continue to invest in innovative, science-based management initiatives. Floating wetland islands are one such solution. Constructed from recycled materials and planted with native vegetation, floating wetland islands are designed to mimic the functions of natural wetlands. Beneath the surface, extensive root systems create habitat for beneficial microbes that help remove excess nutrients from the water column while providing shelter and foraging opportunities for fish and other wildlife. The result is a floating ecosystem that supports water quality, biodiversity, and habitat enhancement all at once. Research has shown that a 250-square-foot floating wetland island can remove approximately 10 pounds of phosphorus annually while providing roughly the same nutrient-processing surface area as one acre of natural wetland. Considering that a single pound of phosphorus can generate up to 1,100 pounds of wet algal biomass, floating wetland islands have the potential to significantly reduce nutrient availability and help limit some of the factors that contribute to nuisance algal blooms. [caption id="attachment_4363" align="aligncenter" width="1475"] This illustration, sketched by Princeton Hydro Project Manager and Environmental Scientist Ivy Rose, PWS, conveys the functionality of a floating wetland island.[/caption] A Hands-On Community Effort A key component of the Cupsaw Lake project was community participation. Katie coordinated and directed the installation effort, guiding volunteers through each stage of the process. Participants learned how to prepare native plants, install plant plugs within the floating island matrix, apply protective goose netting, and properly deploy and anchor the islands within the lake. The event provided an opportunity for volunteers to learn firsthand about lake ecology, nutrient management, and the role innovative restoration tools can play in protecting local water resources. As the newly planted vegetation establishes itself in the coming months, the islands will become increasingly effective at nutrient uptake while creating a visually appealing focal point within the lake. Over time, the native plantings and submerged root systems will provide valuable habitat for fish, macroinvertebrates, and other wildlife. In addition to their environmental benefits, the islands will serve as a visible reminder of the community's commitment to protecting and enhancing Cupsaw Lake. [gallery link="none" size="large" ids="20130,20131,20129,20132,20137,20135"] [gallery columns="2" link="none" ids="20139,20138"] Part of a Larger Watershed Vision The project also aligns with broader watershed management efforts taking place throughout Ringwood and the New Jersey Highlands. In 2019, the Borough of Ringwood became the first municipality in New Jersey to pursue a regional approach to private lake management through a public-private partnership with four lake associations: Cupsaw, Erskine, Skyline, and Riconda. Situated within the northeast corner of the Highlands region, Ringwood is home to numerous lakes and reservoirs that provide drinking water to millions of New Jersey residents. To support the long-term protection of these resources, the Borough partnered with Princeton Hydro to develop a comprehensive watershed management plan that identifies and prioritizes projects that address both immediate and future water quality concerns. This approach recognizes that healthy lakes require more than in-lake management. Sustainable improvements depend on addressing nutrient and sediment sources throughout the surrounding watershed. And, organizations like Skylands Guardian play a critical role in turning watershed planning into on-the-ground action. Projects like the Cupsaw Lake floating wetland islands complement larger watershed initiatives by improving water quality, enhancing habitat, and fostering community engagement. More About Katie During her more than 11 years with Princeton Hydro, Katie has contributed to a wide range of water quality monitoring programs, fisheries investigations, habitat restoration projects, and watershed assessments. She serves as the firm's primary coordinator for floating wetland island projects and has overseen installations at waterbodies throughout the Mid-Atlantic. In 2017, she became certified as an Island Master Builder through Floating Island International, receiving specialized training in the design, construction, installation, and application of floating wetland island technology. Her expertise helped ensure that the Cupsaw Lake installation project not only achieved its technical objectives but also provided a meaningful educational experience for volunteers and community members. Click here to learn more about Katie. A special thank you to Skylands Guardian for documenting the installation and helping share the story of this exciting community-driven project. To learn more about the Skylands Guardian and how to support the great work they're doing, click here. To learn more about another one of Princeton Hydro's long-term lake management initiative, explore our blog, Two Decades of Lake Management Innovation at Duke Farms, which highlights efforts to protect and monitor the interconnected lakes and ponds across Duke Farms' 2,700-acre property in Hillsborough, New Jersey. [post_title] => Cupsaw Lake Welcomes New Floating Wetland Islands [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => floating-wetland-islands-cupsaw-lake [to_ping] => [pinged] => [post_modified] => 2026-07-22 20:00:47 [post_modified_gmt] => 2026-07-22 20:00:47 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=20084 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 20082 [post_author] => 1 [post_date] => 2026-07-21 20:00:58 [post_date_gmt] => 2026-07-21 20:00:58 [post_content] => Welcome to the latest edition of our Partner Spotlight series, where we highlight the organizations and communities working to improve water quality, strengthen environmental resilience, and invest in the long-term health of their natural resources. This edition features Rockaway Borough and Rockaway Township, in Morris County, New Jersey, and their proactive, science-based approach to protecting Fox's Pond (also known as Park Lake) and its surrounding watershed. Because Fox's Pond spans both Rockaway Borough and Rockaway Township, protecting its water quality requires coordinated planning, ongoing partnership, and a shared vision for long-term watershed management. Looking Beyond the Shoreline Many lake management efforts focus exclusively on conditions within the waterbody itself. Rockaway recognized that lasting improvements require understanding what happens throughout the watershed. In 2022, Princeton Hydro completed a watershed assessment and developed a Watershed Management Plan (WMP) for Rockaway Township that evaluated eleven lakes and ponds throughout the municipality, including Fox's Pond, which was funded by the New Jersey Highlands Council. The WMP identifies watershed factors contributing to nutrient loading and eutrophication and prioritizes practical management strategies for implementation based on urgency, feasibility, and potential to deliver the greatest water quality and ecological benefits. Rather than treating water quality challenges as isolated issues, the WMP established a framework for watershed-wide improvement opportunities. [gallery link="none" ids="20217,20215,20216"] Turning Planning into Funding Using recommendations developed through the Watershed Management Plan, Rockaway Township, with guidance from Princeton Hydro, successfully pursued NJDEP Section 319(h) Water Quality Restoration funding. In 2025, the Township received nearly $400,000 to implement priority recommendations identified through the watershed planning process. The project includes water quality improvements focused on reducing nutrient inputs into Fox’s Pond and Fox Brook, enhancing stormwater treatment, and improving local capacity to manage runoff before it reaches surrounding waterways. A key component of the project is the installation of nature-based green infrastructure practices designed to capture, filter, and naturally treat stormwater at its source. A focal point of the effort is the conversion of an existing rock-lined drainage swale into a vegetated stormwater treatment system with bioretention features and native plants designed to:
Volunteers and community stakeholders gathered at Cupsaw Lake in Ringwood Township, NJ for the installation of two floating wetland islands, an innovative nature-based solution that improves water quality while enhancing biodiversity.
The project was funded by Skylands Guardian, a nonprofit organization dedicated to protecting the natural resources of New Jersey's Highlands region through education, advocacy, and environmental stewardship. In partnership with Skylands Guardian, Princeton Hydro Aquatic Ecologist Katie Walston-Frederick led the hands-on installation event, which transformed native plants and recycled materials into living ecosystems designed to benefit the lake for years to come.
Nestled within the Ramapo Mountains, Cupsaw Lake is a 65-acre freshwater lake in the heart of Ringwood Township. To help preserve its long-term ecological health, local partners continue to invest in innovative, science-based management initiatives. Floating wetland islands are one such solution.
Constructed from recycled materials and planted with native vegetation, floating wetland islands are designed to mimic the functions of natural wetlands. Beneath the surface, extensive root systems create habitat for beneficial microbes that help remove excess nutrients from the water column while providing shelter and foraging opportunities for fish and other wildlife. The result is a floating ecosystem that supports water quality, biodiversity, and habitat enhancement all at once.
Research has shown that a 250-square-foot floating wetland island can remove approximately 10 pounds of phosphorus annually while providing roughly the same nutrient-processing surface area as one acre of natural wetland. Considering that a single pound of phosphorus can generate up to 1,100 pounds of wet algal biomass, floating wetland islands have the potential to significantly reduce nutrient availability and help limit some of the factors that contribute to nuisance algal blooms.
A key component of the Cupsaw Lake project was community participation.
Katie coordinated and directed the installation effort, guiding volunteers through each stage of the process. Participants learned how to prepare native plants, install plant plugs within the floating island matrix, apply protective goose netting, and properly deploy and anchor the islands within the lake. The event provided an opportunity for volunteers to learn firsthand about lake ecology, nutrient management, and the role innovative restoration tools can play in protecting local water resources.
As the newly planted vegetation establishes itself in the coming months, the islands will become increasingly effective at nutrient uptake while creating a visually appealing focal point within the lake. Over time, the native plantings and submerged root systems will provide valuable habitat for fish, macroinvertebrates, and other wildlife. In addition to their environmental benefits, the islands will serve as a visible reminder of the community's commitment to protecting and enhancing Cupsaw Lake.
The project also aligns with broader watershed management efforts taking place throughout Ringwood and the New Jersey Highlands. In 2019, the Borough of Ringwood became the first municipality in New Jersey to pursue a regional approach to private lake management through a public-private partnership with four lake associations: Cupsaw, Erskine, Skyline, and Riconda.
Situated within the northeast corner of the Highlands region, Ringwood is home to numerous lakes and reservoirs that provide drinking water to millions of New Jersey residents. To support the long-term protection of these resources, the Borough partnered with Princeton Hydro to develop a comprehensive watershed management plan that identifies and prioritizes projects that address both immediate and future water quality concerns.
This approach recognizes that healthy lakes require more than in-lake management. Sustainable improvements depend on addressing nutrient and sediment sources throughout the surrounding watershed. And, organizations like Skylands Guardian play a critical role in turning watershed planning into on-the-ground action. Projects like the Cupsaw Lake floating wetland islands complement larger watershed initiatives by improving water quality, enhancing habitat, and fostering community engagement.
During her more than 11 years with Princeton Hydro, Katie has contributed to a wide range of water quality monitoring programs, fisheries investigations, habitat restoration projects, and watershed assessments. She serves as the firm's primary coordinator for floating wetland island projects and has overseen installations at waterbodies throughout the Mid-Atlantic.
In 2017, she became certified as an Island Master Builder through Floating Island International, receiving specialized training in the design, construction, installation, and application of floating wetland island technology. Her expertise helped ensure that the Cupsaw Lake installation project not only achieved its technical objectives but also provided a meaningful educational experience for volunteers and community members.
To learn more about another one of Princeton Hydro's long-term lake management initiative, explore our blog, Two Decades of Lake Management Innovation at Duke Farms, which highlights efforts to protect and monitor the interconnected lakes and ponds across Duke Farms' 2,700-acre property in Hillsborough, New Jersey.
Welcome to the latest edition of our Partner Spotlight series, where we highlight the organizations and communities working to improve water quality, strengthen environmental resilience, and invest in the long-term health of their natural resources.
This edition features Rockaway Borough and Rockaway Township, in Morris County, New Jersey, and their proactive, science-based approach to protecting Fox's Pond (also known as Park Lake) and its surrounding watershed. Because Fox's Pond spans both Rockaway Borough and Rockaway Township, protecting its water quality requires coordinated planning, ongoing partnership, and a shared vision for long-term watershed management.
Many lake management efforts focus exclusively on conditions within the waterbody itself. Rockaway recognized that lasting improvements require understanding what happens throughout the watershed.
In 2022, Princeton Hydro completed a watershed assessment and developed a Watershed Management Plan (WMP) for Rockaway Township that evaluated eleven lakes and ponds throughout the municipality, including Fox's Pond, which was funded by the New Jersey Highlands Council. The WMP identifies watershed factors contributing to nutrient loading and eutrophication and prioritizes practical management strategies for implementation based on urgency, feasibility, and potential to deliver the greatest water quality and ecological benefits. Rather than treating water quality challenges as isolated issues, the WMP established a framework for watershed-wide improvement opportunities.
Using recommendations developed through the Watershed Management Plan, Rockaway Township, with guidance from Princeton Hydro, successfully pursued NJDEP Section 319(h) Water Quality Restoration funding. In 2025, the Township received nearly $400,000 to implement priority recommendations identified through the watershed planning process.
The project includes water quality improvements focused on reducing nutrient inputs into Fox’s Pond and Fox Brook, enhancing stormwater treatment, and improving local capacity to manage runoff before it reaches surrounding waterways. A key component of the project is the installation of nature-based green infrastructure practices designed to capture, filter, and naturally treat stormwater at its source.
A focal point of the effort is the conversion of an existing rock-lined drainage swale into a vegetated stormwater treatment system with bioretention features and native plants designed to:
This project represents a tangible example of how watershed planning can translate into on-the-ground environmental improvements that provide both immediate and long-term benefits on a watershed scale.
“One of the most rewarding aspects of our work in the Rockaway community has been the opportunity to partner with local stakeholders who are committed to turning science into action,” said Princeton Hydro Senior Manager of Aquatics Chris Mikolajczyk, CLM. “What began as a watershed-wide assessment has evolved into tangible restoration projects, successful grant funding, and ongoing lake management efforts. Rather than viewing the assessment as a standalone study, it’s been embraced as a roadmap for future investment and decision-making.”
Through a recently launched monitoring program, Princeton Hydro will track key indicators of lake health, including nutrient concentrations, water clarity, aquatic vegetation, algae communities, and overall water quality. The data collected will help evaluate the effectiveness of ongoing watershed improvements while identifying opportunities for continued enhancement.
Princeton Hydro is proud to continue partnering with Rockaway Borough and Rockaway Township. In addition to supporting watershed planning and implementation efforts, Princeton Hydro conducts annual monitoring of Fox's Pond on behalf of Rockaway Borough. Through continued monitoring, watershed improvements, and data-driven management, Fox's Pond and Fox Brook will remain vibrant ecological assets for generations to come.
Looking for a way to get involved in Rockaway Borough? The Recreation Department is always seeking volunteers to support local events, sports programs, projects, and committees. Whether you can help occasionally or on a regular basis, your contribution helps. To learn more about volunteer opportunities, click here or email recdirector@rockawayborough.org.
For more information about Princeton Hydro’s lake and watershed management work, click here.
Work is underway at Strawbridge Lake as Princeton Hydro and Moorestown Township continue a lake restoration project focused on managing excessive spatterdock growth throughout portions of the lake. The effort is part of a broader, long-term strategy to improve lake health, enhance recreational opportunities, and support the ecological function of this important community resource.
Take a look at some recent photos from the field featuring Field Services Project Manager Matt Kreines operating the Truxor during spatterdock removal activities:
Spatterdock (Nuphar advena), also known as yellow pond lily or cow lily, is a native aquatic plant commonly found in lakes, ponds, and slow-moving waters throughout the eastern United States. While native aquatic vegetation plays an important role in healthy lake ecosystems, excessive growth can reduce open water areas, limit recreation, and alter habitat conditions. At Strawbridge Lake, years of monitoring and management have identified areas where spatterdock has expanded significantly and requires active management.
The current project focuses on removing overabundant spatterdock from targeted sections of the lake while preserving important habitat along the shoreline. In coordination with guidance from the NJDEP Division of Fish and Wildlife, a vegetated buffer is being maintained around portions of the lake's edge to provide refuge and spawning habitat for fish.
Using Princeton Hydro's amphibious Truxor harvesting machine, our team of licensed operators are cutting and removing dense stands of spatterdock from open-water areas throughout the lake. The harvested vegetation is collected and transported to the shoreline, where Moorestown Township Public Works crews remove the material for composting and final disposal.
These photos, captured by Matt Kreines from the operator's seat of the Truxor, provide a firsthand look at the spatterdock removal process in action:
The restoration work also encourages improved water circulation in the lake and increased dissolved oxygen, two important factors in maintaining water quality. The harvesting process also removes nutrients stored within the plant biomass, providing additional benefits.
The spatterdock management project builds upon years of planning, monitoring, and restoration work at Strawbridge Lake. Since the development of the Strawbridge Lake Watershed Management and Restoration Plan, Moorestown Township has invested in a variety of initiatives, including water quality monitoring, aquatic vegetation management, Children's Pond restoration, stormwater improvements, fishery surveys, invasive species management, and public outreach programs.
On May 2, Moorestown Township hosted a public information session at the Moorestown Public Library, where residents joined Township staff and Princeton Hydro Senior Manager and Certified Lake Manager Chris Mikolajczyk, CLM to learn about Strawbridge Lake management and watershed restoration efforts.
The presentation highlighted the history of restoration efforts at Strawbridge Lake, ongoing vegetation management activities, and opportunities for residents to help improve water quality at home through practices such as rain gardens, rain barrels, natural landscaping, and other stormwater management techniques. The session also provided community members with the opportunity to ask questions and learn more about the work taking place throughout the watershed.
As work continues, the Township and Princeton Hydro remain committed to advancing practical, science-based solutions that benefit both the lake and the surrounding community. Click here to learn more about our partnership with Moorestown Township to protect and restore Strawbridge Lake.
Each July, Lakes Appreciation Month invites us to reconnect with one of our most valuable natural resources: our lakes. Since 1998, the North American Lake Management Society (NALMS) has led this initiative to raise awareness about the ecological, recreational, and community benefits lakes provide, while encouraging people to take an active role in protecting them. This year, we’re encouraging you to take your appreciation further by learning, participating, and making meaningful connections with your local lake. Here are four impactful ways to celebrate:
No matter how well you know your local lake, there is always something new to discover. Visit at a different time of day, explore a new access point, or try an activity you've never done before, like birding, early morning paddling, or shoreline photography.
As you spend time on the water or along the shore, take note of the details. Look for changes in water clarity, plant growth, wildlife activity, and seasonal shifts. These small observations can deepen your appreciation and help you better understand how your lake functions. If something doesn't look right, like signs of a harmful algal bloom, the presence of invasive aquatic species, or other water quality concerns, take note and share what you see. Reporting observations to your local lake association or through tools like the bloomWatch app can support monitoring efforts and help protect your lake.
Take your lake visit one step further by joining the annual Secchi Dip-In. This long-running citizen science effort invites volunteers across North America to measure water clarity using a simple Secchi disk. The data collected helps scientists and lake managers track water quality trends over time. Participation is simple and meaningful, and every reading contributes to a larger understanding of lake health.
If you are new to using a Secchi disk, watch our step-by-step instructional video to learn how to take accurate measurements:
Lakes bring people together and create lasting memories. This month, take the opportunity to share your connection to your favorite lake and inspire others to get involved. Join the NALMS #LakesAppreciation Challenge by posting photos or videos that capture your experience. Capture a quiet sunrise, a family outing, or a day spent volunteering and show others what makes your lake special.
Looking for more ways to tell your lake story? Try one of these ideas:
When you share, be sure to include the lake name and the hashtag #LakesAppreciation to connect with the broader celebration.
You don't need to make a big commitment to make a meaningful difference. Small, consistent actions can have a lasting impact on lake health over time. Here are a few simple ways to give back:
Communities across the country are working together to protect and restore their lakes. Your efforts, no matter how small, play an important role in that collective impact.
Lakes Appreciation Month is just the starting point. The actions you take now can help protect and improve your lake all year long. Keep exploring, stay engaged, and continue being a voice for the waters you value. For more ideas and resources, visit NALMS.org. To learn more about how Princeton Hydro supports lake management and restoration, click here to explore one of our projects.
From tidal estuaries and back bays to nearshore marine waters, New Jersey’s coastal environments support fisheries, recreation, wildlife, and local economies. Increasingly, however, these valuable ecosystems are vulnerable to a wide range of harmful algal blooms (HABs). While algae are a natural and essential part of aquatic ecosystems, certain environmental conditions can cause some species to grow excessively, leading to ecological damage, public health risks, and economic losses.
Understanding what HABs are, what drives them, and how nature‑based restoration strategies can prevent or mitigate blooms is essential to supporting the long‑term resilience of New Jersey’s coastal environments.
The term "algae" is ecological rather than taxonomic and encompasses a diverse group of organisms, including eukaryotic algae, such as diatoms and dinoflagellates, and prokaryotic cyanobacteria, commonly referred to as blue‑green algae. Algae are not inherently harmful. In fact, they provide critical ecosystem services, including:
Phytoplankton are microscopic, free‑floating algae found in freshwater, estuarine, and marine environments. Scientists estimate there are 20,000 to more than 100,000 phytoplankton species, but only a small fraction—roughly 100 to 300 species—are capable of forming toxin‑producing harmful algal blooms. Problems arise when these species proliferate rapidly under favorable conditions. These blooms can become harmful when they produce toxins, deplete oxygen, shade submerged vegetation, or otherwise disrupt ecosystem function.
While most harmful algal blooms are caused by phytoplankton, large, fast‑growing macroalgae can also create serious environmental and economic challenges when conditions allow them to proliferate. A well‑known example is Sargassum, a floating seaweed that can form extensive mats across the ocean surface. During periods of rapid growth, these mats can block sunlight from reaching coral reefs and other sensitive habitats. When Sargassum washes ashore in large quantities, it can deter tourism and recreation. As the algae decomposes, it releases hydrogen sulfide gas, producing strong odors that make nearby coastal areas unpleasant to visit. While Sargassum blooms occur most summers along the coast of south Florida, the severity and extent of these events vary considerably from year to year.
HABs can form in freshwater systems, brackish estuaries, and coastal marine waters, and they are particularly dangerous with myriad when they produce toxins that affect humans, pets, livestock, fish, shellfish, and wildlife.
Below is a closer look at the dominant types of marine HABs in the region, the organisms responsible, and the environmental conditions that influence their development.
Brown tides are associated with several diatom genera, such as:
These blooms are influenced by a combination of physical, chemical, and climatic factors, including:
Ulva, commonly known as sea lettuce, is a green macroalga that can form extensive blooms in shallow, nutrient‑rich estuaries. Another common bloomer, Enteromorpha, is now considered genetically equivalent to Ulva. Although Ulva blooms are non‑toxic, they can still cause serious ecological and social impacts:
Cyanotoxins should not be confused with taste‑and‑odor (T&O) compounds. Cyanotoxins are colorless, tasteless, and odorless whereas T&O compounds, such as geosmin and MIB, cause earthy or musty smells. Cyanobacteria can produce T&O compounds without toxins as well as toxins without noticeable odors.
This distinction can complicate detection and public perception of risk.
These HABs, the region's most common, illustrate the wide range of organisms, toxins, and ecological pathways through which algal blooms can affect coastal systems. Although they differ in form, from microscopic phytoplankton to expansive mats of macroalgae, they are often driven by a common set of environmental conditions that favor rapid growth and persistence. Climate change is intensifying many of these drivers. Rising water temperatures, altered precipitation patterns, and longer periods of stratification increasingly create conditions that favor bloom formation. At the same time, human activities continue to increase excess nutrients to coastal waters. Runoff from agricultural lands, chemicals transported by rainfall and irrigation, and discharges from wastewater treatment facilities all introduce nitrogen and phosphorus into rivers, lakes, and estuaries. These nutrients act as fertilizer for algae, accelerating bloom development.
Nutrient‑laden stormwater runoff does not remain localized, rather, it moves downstream through interconnected watersheds, ultimately reaching estuaries and coastal waters where it can contribute to marine blooms. Understanding these linkages between land use, climate, and algae growth is critical to identifying effective strategies for preventing and managing HABs in coastal environments.
HABs represent a complex and growing challenge in New Jersey’s freshwater, estuarine, and coastal systems. They threaten public health, ecosystems, and coastal economies, but they are not insurmountable. Nutrient control, thoughtful watershed management, and nature‑based restoration strategies are central to preventing, mitigating, and controlling HABs. If you're interested in learning more about our work to identify, assess and mitigate HABs, click here to read about our groundbreaking research project with Friends of Hopewell Valley Open Space to monitor HABs using drone technology, advanced data modeling, and community science across a 73-mile stretch of the Delaware River and 23 associated waterbodies.
Nutrient-driven water quality impairments, particularly harmful algal blooms (HABs), continue to challenge lake managers, municipalities, and watershed organizations across the Northeast. Excess phosphorus and nitrogen can rapidly degrade ecological conditions, limit recreational use, impact sources of potable water, and increase management costs, often despite the implementation of conventional best management practices. As a result, there is growing interest in tools that can complement or augment existing approaches and address nutrients in more targeted ways.
Biochar has emerged as one such tool. While it is best known as a soil amendment, its physical, chemical, and biological properties have prompted increasing use in aquatic systems as a means of improving water quality. Over the past five years, Princeton Hydro has applied biochar in a range of lakes, ponds, streams, and stormwater-related settings across Pennsylvania, New Jersey, and New York. These field applications, supported by monitoring, have provided important insight into when biochar is most effective, where its limitations lie, and why observed improvements in water quality are not always explained by phosphorus removal alone.
Biochar is a carbon-rich, charcoal-like material produced through pyrolysis, a process in which organic biomass is heated in a low-oxygen environment. The resulting material has a highly porous structure and extensive surface area, properties that make it effective at adsorbing nutrients such as phosphorus and nitrogen (Joseph et al., 2021). Because excess nutrients are a primary driver of eutrophication and HABs, biochar has emerged as a promising amendment for aquatic systems and stormwater best management practices (BMPs).
In aquatic applications, biochar is typically installed in permeable sleeves (aka socks) or incorporated into stormwater treatment practices to intercept nutrient-rich water before it enters lakes or ponds. Used biochar can also be repurposed as a soil amendment, adding to its appeal as a sustainable, circular material.
Through approximately half a dozen monitored projects implemented since 2020, several consistent patterns have emerged.
Standing Waters Show the Strongest Response: Biochar has proven most effective in low-flow or standing water environments such as ponds and stormwater basins. In these systems, Princeton Hydro has documented total phosphorus (TP) removal rates as high as 80%, with soluble reactive phosphorus (SRP) reductions approaching 97% in some stormwater ponds (Princeton Hydro, Lake Hopatcong Report, 2022). The extended contact time between water and biochar in these settings appears to be a key driver of performance.
Flow and Contact Time Matter: In streams and fast-moving stormwater infrastructure, nutrient removal rates tend to be lower, with phosphorus reductions typically closer to 50%. While still meaningful, these reduced efficiencies are largely attributable to limited contact time. Simply put, the shorter the interaction between water and biochar, the fewer opportunities there are for adsorption and other removal processes to occur.
Enhancement to Conventional Stormwater BMPs: Biochar can be particularly effective when paired with stormwater BMPs that primarily rely on sedimentation. Traditional practices often excel at removing particulate-bound phosphorus but are less effective at capturing dissolved forms of phosphorus—the fraction most readily utilized by algae. Incorporating biochar into these systems can enhance removal of dissolved phosphorus, improving overall treatment performance.
Streams Present Physical Challenges: Installing biochar in stream environments presents practical challenges. Even with careful anchoring, large storm events, including remnants of hurricanes, can dislodge biochar sleeves, transporting them downstream or onto streambanks. These risks must be considered during design and often limit the suitability of biochar for higher energy systems.
Chemistry Alone Does Not Tell the Whole Story: At very high pH levels, phosphorus adsorption onto biochar can become less predictable, sometimes exhibiting a “decoupling” between measured phosphorus sorption and observed water quality improvements. Monitoring data from multiple projects indicate that reductions in chlorophyll-a, cyanobacteria abundance, and overall bloom severity cannot always be explained by phosphorus removal alone.
The disconnect between measured nutrient sorption and improved water quality suggests that additional mechanisms are at work. Increasingly, evidence points toward biological processes occurring within and around biochar installations.
Biochar is known to favor the growth and proliferation of heterotrophic bacteria (Moore et al., 2023). These microbial communities may contribute to water quality improvements in the following ways:
This emerging science mirrors what Princeton Hydro has observed in the field: water quality can improve in ways that chemical measurements alone do not fully explain, suggesting that biological processes may be playing an important supporting role.
Since 2020, Princeton Hydro has applied biochar across a range of aquatic and stormwater settings, tailoring each installation to site-specific conditions and management goals. Together, these projects demonstrate biochar’s versatility and its ability to integrate into holistic watershed and lake management strategies, often working best when paired with other nature-based and engineered solutions.
At Duke Farms, a 2,700-acre estate in New Jersey, Princeton Hydro has supported lake and wetland management efforts for more than two decades. Biochar was recently introduced as an additional tool within an established, science-based nutrient management program. By placing biochar in low-flow areas where contact time could be maximized, phosphorus removal was enhanced and improvements in water clarity were observed. This effort highlights how biochar can be layered into long-term management strategies alongside floating wetland islands and other nature-based solutions.
Harvey’s Lake, the largest natural lake in Pennsylvania, has long faced challenges associated with nutrient loading and recurring HABs. As part of a broader stormwater management effort, Princeton Hydro incorporated biochar into select stormwater BMPs to reduce phosphorus before it entered the lake. Installed within targeted stormwater conveyance and treatment features, the biochar helped achieve measurable reductions in dissolved phosphorus, complementing other watershed-scale measures such as vegetated buffers and wetland enhancements. The spent biochar, having captured phosphorus and nitrogen from runoff, was then repurposed as a soil amendment to enrich a 500-square-foot pollinator garden. This repurposing effort served a dual purpose: demonstrating a closed-loop approach to managing excess nutrients while also creating a community-oriented space that supports local biodiversity.
Across multiple stormwater projects in New Jersey and Pennsylvania, biochar has been installed in detention basins, rain gardens, and other stormwater treatment devices. These applications were designed to target dissolved phosphorus, a nutrient form that conventional BMPs can struggle to remove. In several cases, biochar was paired with other nutrient control measures such as floating wetland islands to further improve nutrient capture. Collectively, these projects illustrate how biochar can be adapted and scaled to address local water quality challenges across diverse settings.
At Lake Hopatcong, New Jersey’s largest lake, biochar was deployed as part of a comprehensive, multi-pronged strategy to reduce nutrient concentrations and mitigate HABs. Biochar was installed in permeable flotation bags and placed at targeted shoreline and inlet locations where nutrient loading is most pronounced, including several stormwater inlets and outlets around the lake. Funded through the NJDEP Freshwater HABs Prevention & Management Grant Program and implemented in partnership with the Lake Hopatcong Commission and the Lake Hopatcong Foundation, these installations complemented other in-lake management measures such as floating wetland islands.
In Manhattan's Central Park, Princeton Hydro supported the Central Park Conservancy in developing and implementing a long-term management strategy for the park's network of lakes and ponds, where harmful algal blooms driven by excess nutrients were a persistent concern. As part of a broader, phased approach to improve water quality, biochar was incorporated as a nutrient reduction tool and will be incorporated alongside other measures such as floating wetland islands, aeration and circulation, and stormwater treatment techniques. Used in targeted locations, biochar helped support efforts to reduce nutrient loading and mitigate cyanobacteria blooms within these highly visible urban waterbodies.
Across these projects, biochar installations have been associated with measurable reductions in total and dissolved phosphorus, decreases in chlorophyll‑a concentrations, and lower cyanobacteria cell counts. While performance has varied by site, the strongest and most consistent results have occurred in enclosed or low‑flow environments where contact time is maximized and physical disturbance is minimized. When thoughtfully designed and integrated with other BMPs, these case studies show how biochar can contribute meaningfully to broader efforts to reduce nutrient loads and improve overall water quality.
Biochar is not a one-size-fits-all solution. Reviewing site-specific water quality data is essential to determine whether biochar is an appropriate standalone treatment or should be combined with complementary approaches. Ongoing and future research is focused on better quantifying the relative contributions of chemical adsorption and biological activity associated with biochar. Current studies, including collaborative efforts with academic partners, aim to document pollutant removal capacity, characterize microbial communities, and evaluate biochar’s potential role in degrading cyanobacteria and cyanotoxins. As these processes continue to be studied and further understood in the water quality context, biochar may become an increasingly valuable component of integrated, science-based watershed management strategies.
Dr. Fred Lubnow, Princeton Hydro's Senior Technical Director of Ecological Services, and Jenn Rogers, Executive Director of Friends of Hopewell Valley Open Space (FoHVOS), were recently featured on the Native Plants, Healthy Planet podcast to discuss the collaborative, first‑of‑its‑kind initiative to monitor Harmful Algal Blooms (HABs) in the Delaware River Watershed using drones, spatial analysis, and community science.
The Delaware River is a lifeline for more than 14 million people, a refuge for wildlife, and a defining natural feature of the region. In recent years, HABs, once confined mostly to lakes and ponds, have expanded into streams and rivers and appearing in colder months. Understanding why this shift is happening, and how to predict it, is essential for protecting water quality, public health, and ecological resilience within the Delaware River watershed and watersheds nationwide.
The podcast, hosted by Fran Chismar and Tom Knezick of Pinelands Nursey, highlights the urgency of addressing HABs and the innovative, cross‑sector partnership driving this work forward. Listen now: Harmful Algal Blooms with Dr. Fred Lubnow and Jenn Rogers.
Jenn Rogers, Executive Director of FoHVOS, brings two decades of conservation leadership to the partnership. Her background spans naturalist education, ecological stewardship, and the development of large-scale restoration and public engagement programs. During her fourteen years with the Mercer County Park Commission, she helped establish both the Environmental Education and Stewardship Departments and oversaw the care of more than ten thousand acres of parkland.
Jenn has spent her career building programs that connect people to the landscapes around them. Her commitment to community-driven conservation make her a key partner in a project that relies on both scientific rigor and public participation. Her perspective highlights how land use, watershed health, and community stewardship are deeply interconnected.
Dr. Fred Lubnow serves as Princeton Hydro’s Senior Technical Director of Ecological Services and brings more than 30 years of experience in limnology, watershed restoration, and community and ecosystem ecology. His career has focused on understanding how freshwater systems respond to nutrient loading, hydrologic change, and long-term environmental pressures. He has designed and led numerous lake and watershed restoration projects, developed USEPA Nine-Element and TMDL-driven watershed plans, and created field-based cyanobacteria and cyanotoxin monitoring programs that are now used across the region.
Fred’s expertise in the taxonomy, ecology, and management of algae, particularly cyanobacteria, has made him a leading voice in the study of HABs. He currently serves on New Jersey’s HABs Advisory Team, where he helps interpret water quality data and advises on mitigation strategies. His scientific leadership guides the technical design and implementation of the Delaware River HAB monitoring initiative.
Now entering its second year, the Delaware River HAB monitoring initiative is expanding both its scientific scope and its community engagement efforts. Building on the foundation established in 2025, the project team is conducting multi‑season drone flights, enhanced satellite‑based surveys, and targeted on‑the‑water sampling along 73 miles of the Delaware River and 24 connected waterbodies. These efforts are designed to strengthen the project’s ability to detect and forecast HABs under a wide range of seasonal and environmental conditions.
Year two also introduces several tools and activities intended to support broader participation and more efficient data collection. This includes the launch of a new ArcSurvey123 mobile data platform to support real‑time volunteer water quality submissions, as well as expanded training opportunities for community members interested in assisting with field sampling. Data collected through these efforts will contribute to the development of advanced algorithms capable of forecasting HAB occurrence at multiple spatial scales.
Funded by the National Fish and Wildlife Foundation's (NFWF) Delaware Watershed Conservation Fund (DWCF), in partnership with U.S. Fish & Wildlife Service, the project continues to be supported by a diverse network of partners across New Jersey and Pennsylvania, including The City University of New York's (CUNY) New York City College of Technology (City Tech), Trenton Water Works, Mercer County Park Commission, The College of New Jersey, Aqua-PA, Philadelphia Water Department, Bucks County Conservation District, Turner Designs, and US Army Corps of Engineers - Philadelphia District's Blue Marsh Lake. Together, these organizations contribute technical expertise, watershed knowledge, and crucial on‑the‑ground support. This collaborative approach remains central to the initiative’s success and long‑term objective: establishing a scalable HAB‑forecasting framework that can ultimately be applied to additional watersheds across the United States.
For a deeper look at the research, partnerships, and shared commitment behind this initiative, listen to the full Native Plants, Healthy Planet podcast presented by Pinelands Nursery. Click here to learn more about the Pinelands Nursery and explore the full library of Native Plants, Healthy Planet podcasts. If you're interested in getting involved in the Delaware River HAB research initiative, the program is currently seeking volunteers for water sampling along the Delaware and select waterbodies. Contact FoHVOS Conservation Biologist Kaitlin Muccio at: kmuccio@fohvos.org for more details.
Friends of Hopewell Valley Open Space (FoHVOS), in partnership with Princeton Hydro, has launched a groundbreaking initiative, “Monitoring Harmful Algal Blooms (HABs) in the Delaware River Watershed Using Drones and Spatial Analysis,” to improve understanding and forecasting of HABs throughout the Delaware River Watershed. Funded by the National Fish and Wildlife Foundation (NFWF), in partnership with the U.S. Fish & Wildlife Service, through the Delaware Watershed Conservation Fund (DWCF), the project leverages drone technology and advanced data modeling to identify environmental conditions that contribute to HAB formation and aims to develop tools and methodologies for early detection and management.
For this innovative research project, FoHVOS, a 501(c)3 and accredited Land Trust located in Hopewell Township, NJ, has teamed with Princeton Hydro. Princeton Hydro conceptualized and designed the initiative and is leading the technical implementation, including field survey design, drone operations, data analysis, and volunteer training.
“The Delaware River is central to Hopewell Valley’s identity. It shapes our way of life, supplies drinking water to 14.2 million people, shelters wildlife like the endangered Atlantic sturgeon, and offers abundant outdoor recreation,” said Jennifer Rogers, Executive Director of FoHVOS. “HABs were once confined to ponds and lakes, but since 2018, they’ve appeared in colder months and spread to streams and rivers. Though land trusts traditionally focus on land, HABs show how land use directly affects water. These blooms often stem from excess nitrogen and phosphorus washed into waterways during storms. Protecting water means restoring land. Our partnership with Princeton Hydro aligns perfectly with our mission. Together, we’re working to better understand and safeguard the Delaware River and its tributaries in both NJ and PA.”
HABs, caused by nuisance growth of cyanobacteria, can have detrimental effects on water quality and are a growing environmental concern nationwide. These blooms deplete oxygen levels, release toxins, and disrupt ecosystems, potentially posing serious risks to drinking water supplies and the health of wildlife, pets, humans, and local economies. Despite advances in environmental monitoring, predicting when and where HABs will occur remains a challenge due to the complex interplay of nutrient loading, temperature, and hydrologic conditions that can lead to rapid bloom proliferation.
To address these challenges, this newly launched initiative integrates drone-based remote sensing, field sampling, and spatial data analysis to collect and interpret detailed environmental data over a two-year period. The study spans multiple monitoring sites along a 73-mile stretch of the Delaware River in New Jersey and Pennsylvania, focusing on near-shore sections and 23 associated waterbodies. The first survey event began in August 2025.
Drones equipped with multispectral imaging systems capture high-resolution spatial data that is then integrated with digital platforms to link remote-sensing with the drone data and on-the-water collected data. The field-based water quality measurements are being collected by a team of trained community volunteers who are using phycocyanin fluorometer meters to measure concentrations of the photosynthetic pigment phycocyanin, which is produced primarily by cyanobacteria. Volunteers enter the data into a customized ArcGIS mobile-friendly survey. These combined datasets will be used to develop and validate predictive algorithms for both planktonic and benthic HABs under varying seasonal and hydrologic conditions.
The following photos depict the RGB (Visual) and corresponding Thermal image from the monitoring flights over Spring Lake in New Jersey:
“This research project represents a major step forward in how we study and manage harmful algal blooms at the watershed scale,” said Dr. Fred Lubnow, Project Lead and Senior Technical Director of Ecological Services at Princeton Hydro. “By integrating satellite data, drone imagery, and on-the-water sampling, we’re developing predictive tools that will enable us take a proactive approach to mitigate HABs, improve response time, and better support our ecosystem health.”
Project partners include New York City College of Technology – The City University of New York, which donated the drone and is supporting remote sensing and data integration; Trenton Water Works, Mercer County Park Commission, and The College of New Jersey which are providing monitoring sites and contributing volunteers for water quality data collection in New Jersey; Aqua-PA and the Philadelphia Water Department, which are providing monitoring sites and volunteers to collect watershed data in Pennsylvania; the Bucks County Conservation District, which is coordinating volunteer data collection; and Turner Designs, whose advanced phycocyanin sensors are being used to calibrate and validate drone-based monitoring data.
In the photos below, volunteers are being trained by Princeton Hydro staff on how to use phycocyanin fluorometers and Secchi disks to gather water quality data and log their findings.
This $1M project is funded through a $488,400 NFWF DWCF grant as part of the NFWF’s Research, Monitoring, & Evaluation Grant category and $513,700 in matching funds from project partners. This grant category aims to support high-performing science that is inclusive, adaptive, and innovative, with the potential to transform the Delaware River Watershed’s future through improved conservation, restoration, and public engagement.
Once complete, the project will produce a comprehensive report summarizing methods, analyses, and data-driven recommendations for practical, low-cost HAB monitoring and mitigation strategies that can be replicated across the Delaware River Watershed and beyond. Crucially, the report will identify tributaries and sources contributing to riverine HABs, enabling targeted restoration of the most affected lands and waters. Data collection will continue through Fall 2025, resume in Spring/Summer 2026, and culminate in a final report expected in 2027.
FoHVOS is a 501(c)3 nonprofit land trust dedicated to conserving the natural resources of the Hopewell Valley region and beyond. Through land preservation, ecological restoration, community engagement, and science-driven initiatives, FoHVOS works to protect and enhance open spaces for future generations. Learn more at www.fohvos.org.
Princeton Hydro is committed to improving our ecosystems, quality of life, and communities for the better. The firm was formed in 1998 with the specific mission of providing integrated ecological and engineering consulting services. Offering expertise in natural resource management, water resources engineering, geotechnical design and investigation, and regulatory compliance, their staff provide a full suite of environmental services throughout the Northeast for the public and private sectors. Project Lead, Dr. Fred Lubnow, is an expert in HAB management and has worked with dozens of lake associations and government agencies to restore lakes, manage watersheds, reduce pollutant loading, address invasive aquatic plants, and mitigate nuisance HABs. To learn more about Princeton Hydro's work to mitigate harmful algal blooms, go here.
Duke Farms, a Center of the Doris Duke Foundation, is a 2,700-acre landscape in Hillsborough, NJ, dedicated to restoring ecosystems, demonstrating sustainable land management, and inspiring environmental leadership. Once the privately-owned estate of J.B. and Doris Duke, the property now welcomes more than 150,000 visitors annually who come to experience its diverse habitats, miles of public trails, and innovative conservation programs.
Situated within the Raritan River Watershed and bordered by a mosaic of rural and suburban development, Duke Farms functions as a living laboratory for nature-based solutions in complex, fragmented landscapes. Its forests, meadows, waterways, and working lands offer an unparalleled setting to advance climate-positive strategies, including restorative land management and decarbonization initiatives, while maintaining an unwavering commitment to protecting wildlife and enriching biodiversity.
For more than 20 years, Princeton Hydro has partnered with Duke Farms to restore, monitor, and manage its interconnected lakes and ponds. In 2001, we developed a comprehensive Lake Management Plan to address water quality challenges, promote ecological balance, and ensure these systems could support both wildlife and public use. Since then, we have provided ongoing updates to align management strategies with the ecological objectives of the Duke Farms Foundation. Over time, the Foundation has expanded public access for education and recreation, highlighting the distinctions between shallow, artificial impoundments and natural lakes while implementing innovative, nature-based techniques for algae and aquatic plant control. Today, Duke Farms’ 11 lakes and ponds, eight of which were included in the original plan, remain central to the property’s water resources and continue to play a vital role in overall ecological health, stewardship programming, and public recreation opportunities.
Great Falls Cove at Duke Farms. Photo by Princeton Hydro Aquatic Ecologist Katie Walston-Frederick.
The original Lake Management Plan integrated routine water quality monitoring, hydrologic and pollutant-load modeling, adaptive aquatic plant management, and targeted interventions to restore ecological balance. Key components included invasive species control, such as Common Carp removal to support native fish populations, and a comprehensive algae and aquatic plant program that included aeration and aquascaping. This multifaceted approach established the foundation for long-term recovery across the lake system.
As Duke Farms expanded public access and strengthened its educational mission, management strategies evolved to emphasize innovative, low-impact techniques for shallow, human-made impoundments. Recent advancements implemented by Princeton Hydro include:
The most recent plan update incorporates techniques that were unavailable when the original plan was developed:
In 2012, Princeton Hydro conducted a detailed hydrologic analysis of Duke Farms’ interconnected lake system to evaluate water management strategies. Historically, water from the Raritan River was pumped into the lakes to maintain water levels. While reliable, this practice introduced elevated nutrients and sediments in the property’s lakes and ponds, degrading water quality and fueling nuisance algal blooms.
The study synthesized pump and discharge records, long-term climate and hydrologic data, and monthly water budgets, and included experimental pumping scenarios to assess alternatives. Results were transformative: under normal conditions, supplemental pumping could be reduced by more than 95%, and even during drought, by about 70%, without compromising lake levels. Based on these findings, Duke Farms adopted a low-volume, seasonal pumping strategy and transitioned to a higher-quality groundwater source, which significantly reduced nutrient loading, improved water clarity, and lowered energy consumption.
Ongoing monitoring remains a cornerstone of the Duke Farms–Princeton Hydro partnership. For each waterbody, the team conducts in-situ data collection, laboratory analyses, visual and observational evaluations, and detailed reporting. Data from continuous monitoring demonstrates sustained improvements in dissolved oxygen, water quality, and overall lake/pond health. This continuous feedback loop informs adaptive management decisions and allows Duke Farms to measure the ecological success of its restoration efforts.
We are proud to partner with Duke Farms in advancing the health and resilience of its water resources, a commitment that not only protects the lakes and ponds on the property but also delivers positive ecological benefits throughout the Raritan River watershed. Click here to learn more about our lake management work in the region. To explore Duke Farms, plan a visit to its beautiful property, sign up for educational programs, or discover ways to get involved in its conservation initiatives, visit Duke Farms’ website.
The Lake Hopatcong Commission, in partnership with Roxbury Township and Princeton Hydro, and with support from the Lake Hopatcong Foundation, has been awarded a $367,000 Water Quality Restoration Grant from the New Jersey Department of Environmental Protection (NJDEP) for the Lake Hopatcong Watershed Basin Enhancement Project.
The project will retrofit an existing stormwater detention basin with a series of green stormwater infrastructure improvements designed to slow, capture, and naturally treat stormwater runoff. The basin project, located between King Road and Mount Arlington Boulevard in Roxbury Township, was identified in the 2021 Upper Musconetcong River Implementation Plan (WIP) as a priority project to reduce non-point source pollution and improve water quality before stormwater enters the lake at King Cove.
"Roxbury is truly thankful for the Lake Hopatcong Commission. Lake Hopatcong is such a valuable resource and the commission’s work alongside Princeton Hydro has preserved a natural treasure," said Shawn Potillo, Mayor of Roxbury. "We are grateful to the NJDEP for their support and award of this grant. This water basin project in Roxbury will help continue the commission’s purpose of keeping the lake a beautiful place to swim, boat, relax, and call home."
A range of improvements will be incorporated including planting native vegetation and managing invasive species to stabilize soils, support wildlife, and naturally filter pollutants before they reach the lake. Erosion and sediment control measures will further protect the area by reducing stormwater scouring and preventing bank degradation.
In addition to on-the-ground restoration, the project emphasizes public education and outreach to promote best management practices and ongoing watershed stewardship among residents and local partners. Project success will be evaluated through water quality monitoring conducted before and after construction, providing measurable data on the project’s effectiveness in improving water quality.
“Lake Hopatcong’s fight against harmful algal blooms requires a united front, where many projects, like retrofitting stormwater basins to capture nutrients before they go into the lake, collectively make a big impact,” said Dr. Fred Lubnow, Senior Technical Director of Ecological Services at Princeton Hydro. “Thanks to the leadership of the Lake Hopatcong Commission and the Lake Hopatcong Foundation, this collaborative approach is driving real progress toward cleaner water, healthier ecosystems, and a more resilient future for New Jersey’s largest lake.”
The basin enhancement project is funded through NJDEP’s Water Quality Restoration Grant Program, which is supported by the U.S. Environmental Protection Agency under Clean Water Act Section 319(h). Along with the state grant, the project includes a $200,000 local match from the Commission, Roxbury Township, and the Lake Hopatcong Foundation, and builds on a $98,000 planning grant awarded by the New Jersey Highlands Council in 2024 that helped prepare the project for implementation and future grant opportunities.
“This project represents an important step forward in improving Lake Hopatcong’s water quality and reducing pollutants that contribute to harmful algal blooms,” said Ron Smith, Chairman of the Lake Hopatcong Commission. “We’re grateful to NJDEP, Roxbury Township, Princeton Hydro, the Foundation and the Highlands Council for their continued partnership in protecting this vital resource.”
The Lake Hopatcong Commission is an independent state agency created in, but not of, the New Jersey Department of Environmental Protection. LHC is recognized as a steward of the lake and watershed. The 11-member Board of State and local appointees include representatives of the four municipalities and two counties surrounding Lake Hopatcong. LHC is responsible for fulfilling the obligations of the Lake Hopatcong Protection Act, to safeguard Lake Hopatcong as a natural, scenic, and recreational resource. To learn more, click here to visit lakehopatcongcommission.org.
For over 30 years, Princeton Hydro has been proud to work alongside the Lake Hopatcong Commission and Lake Hopatcong Foundation in support of the lake’s health and resilience. Through these partnerships, and with the support of numerous funding agencies, a wide range of projects have been implemented to reduce pollutant loads, manage stormwater runoff, address invasive species and harmful algal blooms, and enhance habitat quality—helping to protect both the lake and the communities that depend on it. To learn more about our collaborative efforts, click here.
The Borough of Mountain Lakes has received grant funding from the New Jersey Highlands Council to develop a comprehensive Lake and Watershed Management Plan for nine lakes within the Borough. To lead this effort, the Borough engaged Princeton Hydro, a leader in ecological and engineering consulting. The initiative will focus on characterizing hydrologic and nutrient dynamics within the Borough’s lake systems and watersheds to guide targeted water quality improvement and management strategies.
“Mountain Lakes takes great pride in our lakes, which play an important role in defining our community. Through our partnership with the Highlands Council and Princeton Hydro, we’re taking a proactive, data-driven approach to protecting both the environmental and recreational value of our lakes and waterways, with the goal of preserving these vital natural resources for generations to come,” said Borough of Mountain Lakes Manager Mitchell Stern.
A selection process was undertaken by the Borough of Mountain Lakes, Princeton Hydro, and the New Jersey Highlands Council to define the scope of this Lake and Watershed Management Program. In accordance with Policy 1L2 and Objective 1L2a of the NJHC Regional Master Plan, which establish lake management tiers and prioritize lakes greater than 10 acres for protection and management, nine lakes were selected for the study: Birchwood Lake, Crystal Lake, Wildwood Lake, Sunset Lake, Mountain Lake, Shadow Pond, Olive Pond, Grundens Pond, and Cove Pond. These lakes represent the waterbodies in the Borough and were chosen to ensure the program focuses on areas with the greatest potential impact on water quality, watershed function, and community value.
Princeton Hydro’s work will include watershed modeling, hydrologic and pollutant load analyses, and in-lake and watershed-based water quality monitoring. Once the data is analyzed, Princeton Hydro will develop a General Assessment Report that identifies the primary drivers of eutrophication and outlines a prioritized set of management strategies to effectively reduce nutrient loading and enhance long-term lake health.
“The regional, science-based approach to lake and watershed management has proven to be a powerful tool for municipalities in the Highlands Region,” said Christopher Mikolajczyk, CLM, Senior Manager of Aquatics at Princeton Hydro, Certified Lake Manager, and lead designer for this initiative. “We’re excited to collaborate with Mountain Lakes to help identify cost-effective, data-driven strategies that will enhance water quality throughout the watershed and help safeguard these treasured natural resources.”
The New Jersey Highlands Water Protection and Planning Council (Highlands Council) is a regional planning agency that partners with municipalities and counties in the Highlands Region to promote proactive watershed protection. Established under the New Jersey Highlands Water Protection and Planning Act of 2004, the Council has funded numerous water-quality-related planning initiatives.
Historically, municipalities and private lake associations have managed water quality issues independently. However, taking a coordinated, watershed-based approach enables communities to more effectively address pollution sources, improve water quality, and prevent the spread of invasive species and harmful algal blooms.
Mountain Lakes joins several other Highlands region municipalities that have received Highlands council funding to implement similar lake and watershed management initiatives. In 2019, the Borough of Ringwood became the first municipality in New Jerey to adopt a regional, public-private approach to lake management, partnering with four lake associations across six lakes. Since the completion of the Ringwood plan, NJDEP has funded recommendations from the plan. This model has since inspired additional projects, including watershed assessments for West Milford Township, Rockaway Township, Byram Township, Vernon Township, and Somerset County Parks Commission. Princeton Hydro worked with each agency to develop the respective scope of work to secure grant funding from the Highlands Council.
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