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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. [gallery link="none" size="medium" ids="9215,19122,9225"] What Is Biochar and Why Use It in Waterbodies? 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. [gallery link="none" columns="2" size="medium" ids="19134,9226"] Aquatic Ecologist Katie Walston-Frederick (right) leads a biochar sleeve filling session. Katie and her team members wear full protective equipment when handling biochar due to the fine, carbon-based nature of the material. Lessons Learned from Five Years of Field Applications 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. Beyond Adsorption: The Role of Biology 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:
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.
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 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.
The New Jersey Department of Environmental Protection (NJDEP) recently announced $8 million in Water Quality Restoration Grants to support projects that reduce nonpoint source pollution, mitigate harmful algal blooms, restore riparian areas, and enhance watershed and climate resilience. Funded through Section 319(h) of the federal Clean Water Act and administered by the DEP's Watershed and Land Management Program, these grants were awarded to municipalities, nonprofit organizations, and academic institutions across the state.
Princeton Hydro is proud to be a partner on five of the 17 funded projects. Our contributions vary by project and encompass activities such as engineering design, water quality assessment, watershed-based planning, and technical support for implementing stormwater and habitat restoration measures. Let's take a deeper look at these collaborative efforts:
The Watershed Institute received $205K in 319(h) grant funding to develop a watershed-based plan for the Assunpink Creek watershed, located within the Raritan River Basin. This watershed spans 11 municipalities across two counties, where varied landscapes and demographics share common challenges such as localized flooding, stormwater management, and water quality degradation, highlighting the need for a coordinated, watershed-wide, science-driven approach.
The plan will evaluate pollution sources and identify large-scale restoration opportunities, including green infrastructure and riparian buffer restoration, to improve water quality and reduce flooding. It will also assess the cost, feasibility, and pollutant reduction potential of proposed measures to ensure practical implementation. Princeton Hydro supported the Institute in developing the grant proposal and planning framework, leveraging our expertise in watershed-based planning to prioritize nature-based solutions that address both water quality and climate resilience. This initiative represents a critical step toward regional collaboration, enabling upstream and downstream communities to work together on strategies that strengthen watershed health, protect public safety, and build long-term resilience.
The Lake Hopatcong Commission (LHC) was awarded $366K to retrofit an existing stormwater detention basin between King Road and Mount Arlington Boulevard in Roxbury Township. This retrofit is part of a larger Watershed Implementation Plan that Princeton Hydro developed in collaboration with LHC, which prioritizes nutrient reduction and stormwater management strategies across the Lake Hopatcong watershed. Over the past several years, LHC has actively implemented multiple elements of this plan to address harmful algal blooms (HABs) and improve water quality.
For this project, Princeton Hydro is providing engineering design and technical oversight to transform the existing basin into a green stormwater infrastructure system that slows, captures, and naturally treats runoff before it enters King Cove. The design incorporates native vegetation, invasive species management, and erosion control measures to stabilize soils and filter pollutants, reducing nutrient loading, which is one key driver of HABs. Public outreach and pre- and post-construction water quality monitoring will ensure performance tracking and measurable improvements. This basin retrofit represents a critical step in a coordinated, science-based approach to restoring ecological health and water quality in New Jersey’s largest lake.
Jefferson Township received $350K in grant funding to develop an Emerging Contaminants Management Plan for Cozy Lake, focusing on cyanotoxins and HABs. Cozy Lake is a 28-acre waterbody within a 1,152-acre sub-watershed that includes both forested (60%) and developed (29%) land. The lake is fed by the Rockaway River at its northern end and a smaller southeastern inlet, with outflow through a dam on the western edge.
The shoreline is primarily residential lawn with minimal emergent wetlands, and several inlets and rock-lined drainage ditches exhibit erosion and lack slope protection, contributing to sediment loading. Princeton Hydro provided early technical input to shape this innovative project with the creation of a comprehensive Jefferson Township Lake and Watershed Restoration and Protection Plan. As part of the plan, Princeton Hydro made recommendations for Cozy Lake, which included enhancing shoreline buffers with native vegetation and installing living shorelines at select properties to stabilize soils, filter stormwater and reduce nutrient loading, improve habitat quality, and enhance community access. These measures, combined with in-lake monitoring and proactive management strategies, will help mitigate HABs and protect ecological and public health.
Rockaway Township received $399K in grant funding to implement elements of its Watershed Implementation Plan, focusing on green infrastructure stormwater management and nutrient reduction to improve water quality. The project will retrofit the municipal complex by converting a rock-lined drainage swale into a vegetated swale with a bioretention basin, designed to filter stormwater runoff and reduce nonpoint source pollutants entering Fox’s Pond and Fox Brook.
Princeton Hydro played a key role in developing the Watershed Implementation Plan, which encompasses 11 private lakes within the Rockaway River watershed, prioritizing critical locations for intervention and designing cost-effective green infrastructure BMPs. This regional approach aligns with strategies recommended by NJDEP and the Highlands Council. The plan included a comprehensive watershed-based assessment to identify and quantify factors contributing to eutrophication, evaluate management measures, estimate costs, and establish an implementation schedule. Princeton Hydro authored the final report, which guided the Township in applying for the Section 319(h) grant and now informs the design and construction of green stormwater infrastructure that will deliver measurable water quality improvements while supporting ecological restoration goals.
Green Trust Alliance (GTA), a nationally accredited land trust and public charity dedicated to accelerating large-scale conservation, received $1.39 million in NJDEP funding to implement green infrastructure improvements at Pinelands Regional High School in Tuckerton, New Jersey. This initiative targets the Tuckerton Creek watershed, which drains into Tuckerton Creek and ultimately flows into Barnegat Bay—a critical estuary spanning 33 municipalities in Ocean County and four in Monmouth County. The retrofit will transform the school’s stormwater detention basin into a multi-functional system that mimics natural hydrology, enhances flow control, and improves water quality locally and in the larger Barnegat Bay watershed.
Working with GTA and GreenVest, Princeton Hydro is serving as the design engineer, applying nature-based engineering and ecological restoration techniques to intercept, evapotranspire, and infiltrate stormwater runoff at its source. In addition to its technical objectives, the effort includes a strong community engagement component and an educational platform for students. By bringing green infrastructure into the school environment, the initiative provides hands-on experience with water resources, stormwater management, and ecological engineering, help to build STEM skills while fostering a deeper connection to the surrounding landscape and an understanding of how natural systems work together to support environmental and community health.
Princeton Hydro also assisted several of these partners in developing successful NJDEP Section 319(h) grant applications, providing technical documentation, conceptual designs, and pollutant load reduction estimates to strengthen the proposals.
To date, the Murphy Administration has awarded more than $33M in Water Quality Restoration grants to improve the health of waterways in all corners of the state. Click here to read about all the 2025 grant funding recipients and their innovative projects.
As NJDEP Environmental Protection Commissioner Shawn M. LaTourette noted in the department's press release, “Enhancing the ecological health of our lakes, rivers, streams and coastal waters has long been a priority of the Murphy Administration. The Department of Environmental Protection is pleased to award these grants that will help our partners advance a variety of strategies to improve the health of these waterways and enhance the quality of life in our communities.”
We are proud to play a continued role in advancing that mission: helping communities implement practical, data-driven solutions that make a measurable difference for New Jersey’s waterways and the people who depend on them. Click here to learn more about our work to protect natural habitat and restore water quality throughout the New Jersey.
Nestled at the foot of the Blue Ridge Mountains, Smith Mountain Lake is the largest lake entirely within the Commonwealth of Virginia. Spanning over 20,000 acres with 500 miles of shoreline, the lake's northern and eastern boundary is marked by Bedford County, while Franklin and Pittsylvania counties define its southern and western edges. Created in 1963 by impounding the Roanoke River with the Smith Mountain Dam, the lake serves multiple purposes, including hydroelectric power, public water supply, and recreation.
Throughout the 1960s and 1970s, the area surrounding Smith Mountain Lake was predominantly rural farmland. In the 1980s, however, the lake's natural beauty, recreational appeal, and proximity to Roanoke and Lynchburg began to draw increased attention. This surge in interest sparked a boom in residential and commercial development, transforming Smith Mountain Lake into a vibrant and bustling community.
Today, Smith Mountain Lake not only provides electricity and drinking water, it is also home to 21,000 residents and stands as a premier recreational resource. Thousands flock to Smith Mountain Lake each year to enjoy boating, swimming, fishing, and other water activities. The lake's shores are now dotted with resorts, condominiums, year-round residences, and outdoor industry businesses. The lake's waters and shoreline also provide vital habitats for aquatic plants, animals, birds, and other terrestrial wildlife.
The rapid growth of this pristine lake community underscores the importance of effective environmental management to preserve water quality, strengthen the shoreline, manage stormwater runoff, and protect the local native biodiversity of the lake and its watershed.
The lake is fed by two main tributaries—the Blackwater River and the Roanoke River. The Roanoke River, the larger of the two, drains a watershed that includes the Roanoke Metropolitan area, while the Blackwater River flows through mostly rural and agricultural land.
In 2023, a significant outbreak of harmful algal blooms (HABs) in the Blackwater River subwatershed raised concerns for the Smith Mountain Lake Association (SMLA). These blooms, primarily driven by agricultural runoff, led to swimming advisories and highlighted the need for a comprehensive approach to managing and mitigating these environmental threats.
Recognizing the urgency of the situation, SMLA sought the expertise of Princeton Hydro. The mission: to investigate conditions that cause HABs, protect the lake from future outbreaks, and ensure the long-term health of this vital freshwater resource.
The project team’s approach began with a thorough review of historical water quality data. Collaborating with SMLA and regulatory bodies including the Virginia Department of Environmental Quality (VDEQ), U.S. Geological Survey (USGS), and U.S. Army Corps of Engineers (USACE), Princeton Hydro compiled a comprehensive dataset. This historical context was crucial for understanding past trends and informing the 2024 Watershed Assessment. SMLA and Ferrum College contributed over 38 years of data through their Volunteer Water Quality Monitoring Program, documenting crucial indicators such as nutrient levels, bacterial counts, and algal blooms. This extensive dataset has been essential in informing effective lake management practices and shaping strategies to address current environmental challenges.
Employing the MapShed model, the team carried out a comprehensive hydrologic and nutrient loading analysis of the Blackwater River subwatershed. They evaluated critical factors, including phosphorus, nitrogen, and sediment levels, to identify and prioritize areas requiring targeted nutrient and sediment management strategies.
To describe its basic function, the MapShed model applies pollutant loading rates to different land cover types, like low-density development or forested wetlands, based on their area. It then uses weather data, soil characteristics, and slopes to adjust these results. The model simulates daily pollutant loads over 30 years using actual climate records, providing monthly and annual outputs. Users can adjust various inputs, like septic system efficiency and population density, to see how the changes affect pollutant loads and water flow.
This analysis laid the foundation for determining effective, focused interventions to curb nutrient runoff and mitigate future HABs.
In March 2024, an Overwintering Incubation Study was conducted to understand cyanobacteria behavior. Sediment and water samples were taken from six nearshore locations known for high cyanobacteria counts in Summer 2023. At each site, the team also documented temperature, dissolved oxygen, specific conductivity, pH, chlorophyll-a, phycocyanin (PC), and phycoerythrin (PE).
The map below identifies the locations of each of the six sampling sites:
For each sample, the lake water was filtered and then incubated with respective sediments to determine the presence and what types of algae may be overwintering. The water and sediment samples were incubated over a period of 15 days at a temperature of approximately 77 degrees Fahrenheit and a light intensity of 2800 lux.
After eight days, the water and sediment samples were removed from the incubator, slightly stirred and then in-situ measurements for PC and PE were collected. These two supplemental pigments are almost exclusively produced by cyanobacteria. While PC is associated with primarily planktonic genera, PE is more associated with benthic genera. Thus, measuring the concentration of these pigments can be used to estimate cyanobacteria biomass as well as provide guidance on the monitoring and management of HABs (planktonic vs. benthic).
After 15 days, the samples were again removed from the incubator, slightly stirred, and then measured for PC and PE to identify and count any overwintering cyanobacteria and determine all the types of algae present.
This study offered critical insights into the conditions that enable cyanobacteria to endure winter and proliferate during warmer months. By understanding the connection between overwintering cyanobacteria and HABs in the lake, we can enhance predictive capabilities and develop more effective management strategies. Two particularly notable findings from the study include:
Beyond the initial assessment on the Blackwater River, ongoing monitoring of Smith Mountain Lake’s water quality is crucial for understanding and managing the conditions that trigger HABs. SMLA’s Water Quality Monitoring Program developed and managed by Ferrum College continues the work of tracking the trophic state of the lake. Algal community composition, tributary sampling, and bacterial monitoring are part of this comprehensive 38-year effort. Consistent sampling and water quality monitoring can help identify cyanobacteria and akinetes, the dormant spores that lead to bloom formation.
Because the VDEQ budget historically contains no funding for inland waterway HAB research and response, SMLA actively lobbied the Virginia General Assembly for the allocation of $150,000 for the creation of a watershed study. This request was included in the State budget signed in March of 2024 and the work to develop the objectives and scope of the study is underway now.
Community involvement is also vital for maintaining Smith Mountain Lake as a cherished resource. To this end, SMLA has launched "Dock Watch," a new community science volunteer program designed to monitor HAB activity. Beginning in May of 2024, volunteers have been collecting water samples at select docks around the lake and are examining them to better understand cyanobacteria activity levels and trends. All of the water quality data collected at the lake is from main channel locations. The primary recreational contact with the lake water by residents is at their docks. This data is uploaded to NOAA's Phytoplankton Monitoring Network, contributing to a national database used for HAB research. This collective effort ensures rapid identification and tracking of HAB activity, benefiting both the local community and environmental research on a national level.
“This project exemplifies a holistic approach to lake management and environmental stewardship, integrating historical data, advanced modeling, and community engagement to prioritize and implement innovative strategies that effectively mitigate HABs and protect water quality,” said Chris L. Mikolajczyk, Princeton Hydro’s Senior Manager of Aquatics and Client Manager for Smith Mountain Lake. “This ongoing work highlights the importance of science-based interventions in preserving our precious natural resources.”
The Smith Mountain Lake Association is a 501(c)3 nonprofit with the mission to keep Smith Mountain Lake clean and safe. Founded in 1969, SMLA is the longest serving advocate for the Smith Mountain Lake community, and its focused efforts help to retain the pristine beauty of the lake and the vibrant local economy. Click here to learn more and get involved.
Over the last two decades, the Princeton Hydro team has improved water quality in hundreds of ponds and lakes, restored many miles of rivers, and enhanced thousands of acres of ecosystems in the Northeast. From species surveys to water quality monitoring, our professionals perform comprehensive assessments in order to understand the landscape. Using tools like ArcGIS, we can map and model the watershed and arrive at holistic solutions for resource management. Our natural resources and lake management experts are complemented by our field team who utilize amphibious vehicles for mechanical invasive species removal, install aeration systems to improve water quality, and conduct natural lake treatments to manage algal blooms. We have secured millions of dollars in grant funding for watershed and ecological restoration projects on behalf of our clients.
Click here to learn about the Watershed Management Program in Somerset County, for which we recently helped secure grant funding from the New Jersey Highlands Water Protection and Planning Council.
In recognition of World Water Day on March 22, it's important to acknowledge and explore the challenges affecting our freshwater ecosystems. In this blog post, we explore one of those said challenges: Harmful Algal Blooms (HABs).
HABs, characterized by rapid overgrowths of cyanobacteria, have increasingly drawn attention due to their detrimental effects on water quality and aquatic ecosystems. With the onset of spring, rising temperatures create favorable conditions for cyanobacteria growth, setting the stage for potential bloom occurrences in the months ahead. Over recent summers, lakes and freshwater bodies across the nation have faced closures and health advisories due to HAB outbreaks, underscoring the urgent need to address this issue.
Cyanobacteria, often referred to as blue-green algae, are naturally occurring microorganisms in aquatic environments. However, under specific conditions—such as warm temperatures and nutrient-rich waters—these organisms can proliferate rapidly, forming blooms that pose risks to the health of humans, wildlife and aquatic species, local economies and overall ecological balance.
The interplay between climate change and HABs is undeniable: Rising temperatures and altered precipitation patterns create favorable conditions for cyanobacteria growth, exacerbating bloom occurrences. The absence of snow cover and early ice melt further accelerates this process, allowing cyanobacteria to flourish earlier in the year. Over the past few summers, lakes and fresh-waterbodies across the nation experienced closures and health advisories as a result of HAB outbreaks, emphasizing the urgency of addressing this issue.
In light of these challenges, proactive measures are crucial for mitigating the impacts of HABs. Early sampling efforts, initiated as early as March or April, enable the detection of cyanobacteria and akinetes, dormant spores that contribute to bloom formation. Additionally, reducing nutrient inputs, particularly phosphorus, into waterways is essential for preventing HABs.
As we reflect on the significance of water resources on World Water Day, it’s imperative to recognize the importance of addressing threats such as HABs. By raising awareness, fostering collaboration, and implementing effective strategies, we can work towards safeguarding the health and sustainability of our freshwater ecosystems.
In this spirit, we invite you to join the conversation at the Harmful Algal Bloom Summit 2024, hosted by the New Jersey Department of Environmental Protection. This virtual seminar, taking place on March 27, is free to attend and offers a platform for stakeholders to exchange insights, discuss best practices, and explore innovative solutions for managing HABs.
This year's Summit, which is titled “Unlocking the Puzzle of Harmful Algal Blooms," includes a keynote address and three educational sessions - "Growth Through Reflection: Lessons Learned," "Innovative Tools and Applications," and "Beyond the Numbers" - each featuring a variety of expert presentations. Princeton Hydro Senior Technical Director of Ecological Services Dr. Fred Lubnow is presenting on "Quantifying Overwintering Cyanobacteria and How They May Impact the Monitoring and Management of HABs."
Get more information and register here.
As we commemorate World Water Day 2024, let us reflect on the interconnectedness of water and life. Small actions taken today can have a profound impact on preserving water quality for future generations. Join us in making a commitment to promote and do our part to support a sustainable future for our freshwater ecosystems.
Harmful Algal Blooms (HABs) represent the rapid proliferation of cyanobacteria, also known as blue-green algae. While cyanobacteria are not technically algae but rather single-celled aquatic organisms related to bacteria, they possess the ability to photosynthesize like algae. These tiny microorganisms naturally inhabit aquatic ecosystems. However, under specific circumstances, such as heavy rainfall followed by scorching sunshine, they can rapidly multiply, resulting in the formation of cyanobacteria blooms, commonly known as HABs.
HABs can wreak havoc on waterbodies, leading to significant water quality issues and the unsightly appearance of surface scum, sometimes accompanied by unpleasant odors. The consequences extend beyond aesthetics and pose economic challenges for communities reliant on local lakes and waterways for jobs and tourism. Furthermore, HABs can produce highly toxic substances that pose serious risks to humans, aquatic life, and animals, including our beloved pets, wildlife, and livestock.
The effects of HABs on animals vary depending on factors such as the animal's size, exposure to cyanobacteria, duration of exposure, specific toxin types, and concentrations. Animals are often the first victims, drawn to bodies of water containing cyanobacteria due to their natural instincts. Dogs, in particular, are vulnerable as they may unwittingly ingest contaminated water during play. Livestock and wildlife are also at risk when drinking from contaminated water sources.
In 2021, researchers published a groundbreaking study linking cyanobacteria-generated neurotoxins to the deaths of eagles and waterbirds. After extensive research spanning three decades, scientists determined that cyanotoxins are responsible for a fatal neurological disease called vacuolar myelinopathy, commonly affecting waterbirds, raptors, and bald eagles.
Cyanobacterial poisoning symptoms can manifest within minutes to a few hours, depending on the severity of exposure. Dogs, in particular, may exhibit symptoms rapidly. Common signs include an accelerated heart rate, breathing difficulties, excessive salivation, disorientation or depression, vomiting or diarrhea, skin irritations, and neurological symptoms such as muscle weakness, dizziness, seizures, or paralysis.
It is crucial to seek immediate veterinary care or contact the Poison Control Center if you suspect your pet or livestock may be experiencing symptoms caused by harmful algae, cyanobacteria, or their toxins. The following 24-hour pet poison hotlines are available for assistance:
To protect your pets and livestock, avoid letting them come into contact with surface scums or heavily discolored water. In case of exposure, rinse them with clean water as soon as possible, as HABs can cling to their fur and pose health risks when they groom themselves. This is particularly important because certain HABs release fast-acting nerve toxins that can be especially dangerous for dogs swimming in affected areas.
Here are some additional steps you can take to safeguard yourself and your pets from the harmful effects of algae and cyanobacteria:
By staying informed and implementing necessary precautions, we can protect ourselves, our pets, and the environment from the risks associated with HABs. For further HABs related information and guidance, click here to watch a Facebook Live presentation with Princeton Hydro HABs experts. To get involved with monitoring and tracking harmful algal blooms, check out the bloomWatch App, a valuable tool for identifying and reporting potential HAB sightings to local authorities.
Our lakes in New Jersey are an invaluable resource for clean drinking water, outdoor recreation, and agriculture and provide habitat for aquatic flora and fauna. Home to about 1,700 lakes, the “Garden State” is also the most densely populated state. Excess nutrients from fertilizers, roadway pollutants, overdevelopment, and failing septic systems can end up in our lakes and impair water quality. Larger rain events can also cause erosion and instability of streams, adding to the influx of more excess nutrients to our lakes and ponds. Changes in hydrology, water chemistry, biology, and/or physical properties in these complex ecosystems can have cascading consequences that can alter water quality and the surrounding ecosystem. For example, excess nutrients can fuel algal and plant growth in lakes and lead to issues like harmful algal blooms (HABs) or fish kills.
In order to ensure that we protect the overall health of our local waterbodies, it’s important that we look beyond just the lake itself. Implementing holistic watershed-based planning is a critical step in managing stormwater runoff, preventing the spread of HABs, and maintaining water quality. A watershed management plan defines and addresses existing or future water quality problems from both point sources and nonpoint sources of pollutants*. This approach addresses all the beneficial uses of a waterbody, the criteria needed to protect the use, and the strategies required to restore water quality or prevent degradation. When developing a watershed plan, we review all the tools in the toolbox and recommend a variety of best management practices to prevent nutrients from entering lakes or streams. Options include short- and long-term solutions such as green stormwater infrastructure, stream bank stabilization, and stormwater basin retrofits.
To reduce nutrient availability in lakes, one innovative tool in our toolbox is floating wetland islands (FWIs). FWIs are a low-cost, effective green infrastructure solution that are designed to mimic natural wetlands in a sustainable, efficient, and powerful way. They improve water quality by assimilating and removing excess nutrients; 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. FWIs are also highly effective in a range of waterbodies from big to small, from deep to shallow.
Typically, FWIs consist of a constructed floating mat, usually composed of woven, recycled plastic material, with vegetation planted directly into the material. The islands are then launched into the lake and anchored in place, and, once established, require very little maintenance.
It estimated that one 250-square-foot FWI has a surface area equal to approximately one acre of natural wetland. These floating ecosystems can remove approximately 10 pounds of phosphorus each year. To put that into perspective, one pound of phosphorus can produce 1,100 pounds of algae each year, so each 250-square-feet of FWI can potentially mitigate up to 11,000 pounds of algae.
In addition to removing phosphorus that can feed nuisance aquatic plant growth and algae, FWIs also provide excellent refuge habitat for beneficial forage fish and can provide protection from shoreline erosion.
Princeton Hydro has been working with Lake Hopatcong, New Jersey’s largest Lake, for 30+ years, restoring the lake, managing the watershed, reducing pollutant loading, and addressing invasive aquatic plants and nuisance algal blooms. Back in 2012, Lake Hopatcong became the first public lake in New Jersey to install FWIs. In the summer of 2022, nine more FWIs were installed in the lake with help from staff and volunteers from the Lake Hopatcong Foundation, Lake Hopatcong Commission, and Princeton Hydro. The lake’s Landing Channel and Ashley Cove were chosen for the installations because they are both fairly shallow and prone to weed growth. The installation of these floating wetland islands is part of a series of water quality initiatives on Lake Hopatcong funded by a NJDEP Harmful Algal Bloom Grant and 319(h) Grant awarded to Lake Hopatcong Commission and Lake Hopatcong Foundation.
Princeton Hydro partnered with the Greenwood Lake Commission (GWLC) on a FWI installation in Belcher's Creek, the main tributary of Greenwood Lake. The lake, a 1,920-acre waterbody located in both New Jersey and New York, is a highly valued ecological, economical, and recreational resource. The lake also 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 with drinking water.
The goal of the FWI Installation was to help decrease total phosphorus loading, improve water quality, and create important habitat for beneficial aquatic, insect, bird, and wildlife species. The project was partially funded by the NJDEP Water Quality Restoration Grants for Nonpoint Source Pollution Program under Section 319(h) of the federal Clean Water Act. GWLC was awarded one of NJDEP’s matching grants, which provided $2 in funding for every $1 invested by the grant applicant.
Measuring 630+ acres, Harveys Lake is the largest natural lake (by volume) in Pennsylvania and is one of the most heavily used lakes in the area. It is classified as a high quality - cold water fishery habitat (HQ-CWF) and is designated for protection under the classification. Since 2002, The Borough of Harveys Lake and Harveys Lake Environmental Advisory Council has worked with Princeton Hydro on a variety of lake management efforts focused around maintaining high water quality conditions, strengthening stream banks and shorelines, and managing stormwater runoff. Five floating wetland islands were installed in Harveys Lake 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. The FWIs were funded by PADEP.
Working with the Deal Lake Commission (DLC), Princeton Hydro designed and installed 12 floating wetland islands at two lakes in Asbury Park, NJ. In order to complete the installation of the floating wetland islands, our team worked with the DLC to train and assist over 30 volunteers to plant plugs in the islands and launch them into the two lakes. Our experts helped disseminate knowledge to the volunteers, not only about how to install the floating wetland islands, but how they scientifically worked to remove excess nutrients from the water. With assistance from Princeton Hydro, DLC acquired the 12 floating islands – six for Wesley Lake and six for Sunset Lake – through a Clean Water Act Section 319(h) grant awarded by NJDEP.
In addition to the direct environmental benefits of FWIs, the planting events themselves, which usually involve individuals from the local lake communities, have long-lasting positive impacts. 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.
For more information on watershed planning or installing FWI in your community, click here to contact us. To learn more about ANJEC, go here.
Most of us are familiar with the famous quote "Alone we can do so little; together we can do so much.” This sentiment is at the center point of the Highlands Act and Regional Master Plan, which provides funding to help New Jersey’s Highlands communities take a proactive and regional approach to watershed protection.
Historically, private lake associations and municipalities have worked autonomously to address water quality issues and develop improvement plans. Working together, however, and taking a regional approach to lake and watershed management has much farther-reaching benefits. Taking an integrated approach helps improve water quality and reduce incidents of aquatic invasive species and harmful algal blooms (HABs) not just in one waterbody, but throughout an entire region.
The New Jersey Highlands Water Protection and Planning Council (Highlands Council) is a regional planning agency that works in partnership with municipalities and counties in the Highlands Region of northern New Jersey to encourage exactly such an approach. Created as part of the 2004 New Jersey Highlands Water Protection and Planning Act (the Highlands Act), the Highlands Council has funded numerous water-quality-related planning grants throughout the region.
“Watersheds are inherently regional; they don’t follow municipal boundaries. So the Highlands Council is in a unique position to address these challenges from that perspective,” says Keri Green, Highlands Council Science Manager. “It’s critical for municipalities to understand what is entering their lakes from the surrounding watershed before they can effectively address in-lake issues. Across the region, the stormwater inlets and roadways that encircle and affect lakes are owned and maintained by the municipalities, and when we can evaluate these inputs, we can plan for how to address impairments.”
In 2019, the Highlands Council funded a Lake Management planning grant for the Borough of Ringwood that adopted this wider watershed view, and would ultimately become a model for similar Highlands Council grants within the region. The Borough chose to engage the services of Princeton Hydro to support the project work.
“This regional approach to lake and watershed management is the obvious choice from a scientific, technical, and community point of view. Historically, however, this approach is rarely taken,” said Princeton Hydro’s Senior Project Manager, Christopher Mikolajczyk, who is a Certified Lake Manager and lead designer for this initiative. “We were thrilled to work with the Borough of Ringwood and the Highlands Council to set a precedent, which has opened the door for the Townships of West Milford and Rockaway, and will hopefully inspire the formation of more public-private lake management partnerships.”
Rockaway Township in Morris County, New Jersey received Highlands Council grant approval in January to complete a Lake Management Planning Study. Eleven small- to medium-sized lakes in the township are working together for a watershed assessment and comprehensive regional analysis, which will lead to the creation of a Watershed Implementation Plan (WIP). The WIP will recommend and prioritize key watershed management measures that will have big impacts on water quality improvement.
Given the large number of lakes in Rockaway Township, and in an effort to keep the study to a reasonable scope, a selection process occurred with input from the Township Engineering office, the Township Health Department, Princeton Hydro and the Highlands Council. The lakes in the Rockaway Township Watershed Management Program include Green Pond, Egbert Lake, Durham Pond, Lake Emma, Camp Lewis Lake, Lake Telemark, Lake Ames, Mount Hope Pond, Mount Hope Lake, White Meadow Lake, and Fox’s Pond.
“Rockaway Township has been proactive about implementing watershed improvement projects in the past, so we were happy to provide funding to support continuing their efforts focusing on these 11 lakes,” explains Lisa Plevin, Highlands Council Executive Director. “It was a very productive collaboration with Highlands staff working in partnership with the Township to develop an approach and Princeton Hydro preparing a scope of work that met everyone’s goals.”
The watershed assessment will entail a number of analyses, including watershed modeling; hydrologic and pollutant loading analysis; watershed-based and in-lake water quality assessments; and tropic state assessments. The assessment aims to:
Once all the lab data is processed, the watershed modeling is complete, and historical data reviewed, Princeton Hydro will create a General Assessment Report that will summarize the data/observations and identify which watershed management techniques and measures are best suited for immediate or long-term implementation. The team expects to complete the General Assessment Report in the spring of 2022, after a year's worth of 2021 growing season data has been collected.
In October 2020, the Highlands Council approved funding to support a watershed assessment of 22 private and public lakes in West Milford Township. The watershed assessment project is being implemented in two phases:
For Phase 1, which will take place throughout the course of 2021, Princeton Hydro will provide a historic data review; an examination of hydrologic/pollutant loads; a pollutant removal analysis; and watershed water quality analysis. The pollutants to be modeled include phosphorus, nitrogen, sediment, and bacteria, while the hydrology will include estimates of precipitation, runoff, evapotranspiration, groundwater flux, and ultimately streamflow or discharge.
This analysis will aid the Township in selecting, prioritizing and implementing nutrient and sediment load and stormwater management efforts with a focus on watershed projects that have the greatest overall benefit to the long-term management of surface water quality. The report will also identify examples of site-specific locations where wetland buffers, riparian buffers, and lakefront aqua-scaping can be implemented as part of future watershed management efforts.
For Phase 2 of the project, Princeton Hydro will investigate and assess the water quality of each of the lakes in West Milford Township during the growing season of May - October of 2022. This entails collecting bimonthly water quality samples at each lake, including in-situ water quality data consisting of real-time measurement of clarity, dissolved oxygen, temperature, and pH. The sampling events will also include a general survey of aquatic vegetation and/or algae growth, lake perimeter shoreline observations, and monitoring for nuisance waterfowl. These surveys will provide an objective understanding of the amount and distribution of submerged aquatic vegetation (SAV) and algae occurring throughout each lake over the course of the growing season.
The lakes included in this project are: High Crest Lake, Algonquin Waters, Lake Lookover, Kitchell Lake, Lindys Lake, Mt. Laurel Lake, Shady Lake, Wonder Lake, Mount Glen Lakes (Upper/Lower), Carpi Lake, Pinecliff Lake, Van Nostrand Lake, Upper Greenwood Lake, Post Brook Farms, Farm Crest Acres, Mt. Springs Lake, Forest Hill Park, Johns Lake, Gordon Lake, and Bubbling Springs Lake.
At the end of 2019, the Borough of Ringwood became the first municipality in New Jersey to take a regional approach to private lake management through a public-private partnership with four lake associations: Cupsaw, Erskine, Skyline, and Riconda.
The Borough of Ringwood is situated in the northeast corner of the New Jersey Highlands, is home to several public and private lakes, and provides drinking water to millions of New Jersey residents. In order to take an active role in the management of these natural resources, Ringwood hired Princeton Hydro to design a municipal-wide holistic watershed management plan that identifies and prioritizes watershed management techniques and measures that are best suited for immediate and long-term implementation.
Princeton Hydro recently completed a comprehensive assessment of the lakes and watersheds of Ringwood Borough. The assessment included a historical data review, hydrologic and pollutant loading analysis and in-lake and watershed based water quality data studies. The report details the results of Princeton Hydro’s mapping, modeling, and monitoring efforts in each waterbody and its respective watershed, along with specific recommendations for management implementations that are aimed at curbing the effects of nutrient and sediment loading, both within the lakes and their respective watersheds.
“Ringwood, West Milford, and Rockaway are three great examples of how people from different affiliations and backgrounds can come together to address lake and watershed monitoring and management,” said Mikolajczyk. “The key to success is open communication and a common goal!”
To learn more about Princeton Hydro’s natural resource management services, click here. And, click here to learn more about NJ Highlands Council and available grant funding.
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