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.”

[caption id="attachment_18637" align="aligncenter" width="1380"]

Photo by the Lake Hopatcong Commission[/caption]

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 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:

1. The Watershed Institute – Watershed-Based Planning for Assunpink Creek

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.

2. Lake Hopatcong Commission – Watershed-Based Stormwater BMPs

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.

3. Cozy Lake, Jefferson Township – Addressing Emerging Contaminants

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.

4. Rockaway Township – Watershed-Based Green Infrastructure

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.

5. Green Trust Alliance – Green Infrastructure and Community Engagement

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.

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Welcome to the latest edition of our “A Day in the Life” blog series! Today, we’re diving into the world of lake management, biological sampling, and watershed restoration with Patrick Rose, an Environmental Scientist and Project Manager in Princeton Hydro’s Aquatics Division.

Since joining Princeton Hydro in 2019, Pat has played a key role in a range of aquatic projects, from water quality monitoring to fisheries management. His expertise spans in-lake and watershed management, including cyanobacteria monitoring, invasive species control, and statistical analysis of water quality and biological data. Pat has contributed to major initiatives such as developing Nine Element Watershed Implementation Plans for two of New Jersey’s largest lakes, crafting cyanotoxin mitigation strategies, and conducting lake phosphorus assessments to guide restoration efforts.

His journey into aquatics began with a transformative summer course at Lake Atitlán in Guatemala, which ignited his passion for watershed science. After earning both an undergraduate degree in Environmental Science and a graduate degree in Lake Management from SUNY Oneonta, he spent a year with AmeriCorps in Knoxville, Tennessee, working on water quality initiatives with high school students and government agencies. He later completed a co-op managing aquatic invasive plants in the Pacific Northwest before joining Princeton Hydro as an intern in 2016, transitioning to a full-time role in 2019.

Now, let’s step into Pat’s boots (or waders) and see what a typical day in the field looks like, starting with the essential preparations before heading out on the water.

Preparing Equipment and Safety Gear for a Day in the Field

Pat’s days are as varied as the ecosystems he studies. When fieldwork is on the schedule, his morning starts early, often before sunrise. The first step is checking the weather forecast to anticipate any conditions that could impact the day’s work.

Next, he heads to the Princeton Hydro field office, where the team’s trucks, boats, and specialized aquatics equipment, such as the Truxor DM, Marsh Master 2MX-KC-FH, and Airboat, are stored. Before hitting the road, Pat and his team conduct a thorough inventory, gathering all necessary tools and performing critical equipment checks and calibrations.

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“It’s important to ensure that all of the equipment is accounted for and in good working order before leaving for the project site because the site can be a few hours away,” Pat explains. “We calibrate our water quality meters every morning to ensure that all of our measurements are accurate.”

Even for routine monitoring projects at familiar sites, planning is essential. Some projects require full-day or multi-day sampling efforts, especially when testing large waterbodies at multiple locations. A well-structured plan helps keep the process efficient while allowing flexibility for unexpected challenges. As part of the Health and Safety Plan (HASP), the team also reviews emergency protocols, including identifying key points of contact and the nearest hospital in case of an emergency.

If the project involves a boat, the team double-checks all required safety gear, including life jackets, fire extinguishers, flares, air horns, and first aid kits. They also bring protective gloves, especially when working in areas where harmful algal blooms (HABs) are suspected. To prevent the spread of invasive species, they follow strict decontamination protocols, washing boats at the end of each field day.

With the gear packed, safety checks complete, and a solid plan in place, it’s time to hit the water and begin the day’s fieldwork.

On the Water: Conducting Water Quality Monitoring in the Field

Once Pat and the project team arrive at the site, they prepare the boat for launch and conduct a final safety check before heading out on the water.

While they may have specific sampling locations identified in advance, the team remains vigilant for any additional signs of water quality issues, such as HABs, invasive aquatic weeds, or other ecological disturbances. They also take note of positive indicators of a healthy ecosystem, including native fish species, beneficial aquatic plants, and diverse wildlife activity.

Decisions about field measurements at each location are guided by the client’s directives, an approved lake management plan, and any known or suspected water quality challenges the team is working to mitigate.

One of the primary tools Pat relies on is the multiprobe water quality meter, which allows him to efficiently measure key water quality parameters, including temperature, dissolved oxygen, pH, and specific conductivity. This instrument provides real-time data, enabling the team to assess conditions on-site and make informed decisions about sampling and management strategies.

Watch this video where Pat demonstrates how to use a multiprobe water quality meter: [embed]https://youtu.be/6J1oV1qdh4k[/embed]

In addition to using the multiprobe, the team collects water samples for laboratory analysis, testing for conductivity, turbidity, nutrient levels, and, in some cases, fecal coliform bacteria. Shoreline assessments are also a crucial part of monitoring efforts. Pat and his team walk the banks to document erosion, bank stability, and native plant growth, recording their observations through field notes and photo documentation.

With data collection complete, the next step is analyzing the results and translating the findings into actionable insights.

Exploring Lake Hopatcong: A Case Study in Trout Habitat Monitoring

One of the projects Pat is most involved with is the trout habitat monitoring study at Lake Hopatcong, New Jersey’s largest lake. The lake’s trout fishery is a major recreational attraction, drawing anglers from across the region and contributing to the local economy. However, an analysis of 30 years of water quality data revealed a concerning trend—rising surface water temperatures, which can negatively impact trout habitat and survival rates.

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In response to these concerns, the Lake Hopatcong Commission (LHC) Trout Committee was formed in 2021. Working in collaboration with the Lake Hopatcong Foundation and the Knee-Deep Club, the committee launched a three-year trout tagging study to evaluate the lake’s ability to support a sustainable trout population. Princeton Hydro is responsible for all technical aspects of the study, including data collection, analysis, and reporting, with funding provided by the New Jersey Highlands Council.

To understand how habitat conditions fluctuate during peak summer stress periods, Pat and his team conducted weekly sampling in July and August at both deep-water stations and nearshore areas. “We take GPS measurements at every site around the shoreline where we measure temperature and dissolved oxygen,” Pat explains. “Then, we send the locations to our GIS team so they can create detailed habitat maps.”

The study focuses on two key elements:

1. Deep-Water Sampling:

Pat and his team collect in-situ water quality profiles at five deep-water stations across the lake.
Using a calibrated multiprobe water quality meter, they take readings at 1-meter intervals from the surface to the lake bed, refining the intervals near habitat boundaries to improve accuracy.
Core parameters include temperature and dissolved oxygen, with additional data on specific conductance and pH.
These measurements help define the upper habitat limit (controlled by temperature) and the lower limit (governed by dissolved oxygen levels).

2. Nearshore & Stream Sampling:

Pat’s team surveys potential trout refuge areas along the shoreline, where trout might seek cooler, oxygen-rich waters in late summer.
Over the course of the study, they have sampled 116 locations in 2022 and 110 locations in 2023, gathering in-situ temperature and dissolved oxygen data to identify possible refuge sites.
They also measure these parameters in major stream inlets, assessing sources of cooler water that could support trout habitat.

By collecting and analyzing this data, the study provides critical insights into how trout habitat is changing and what can be done to protect and enhance suitable conditions for this important fishery. Click here to read more about the Lake Hopatcong Trout Habitat and Tagging Study.

Building Partnerships for a Thriving Lake

[caption id="attachment_17219" align="alignright" width="444"]

Floating Wetland installation at Lake Hopatcong[/caption]

Managing aquatic projects isn’t just about addressing challenges—it’s about bringing people together to protect and enhance vital ecosystems. Successful water quality restoration efforts thrive on collaboration, education, and community engagement.

“Lakes serve many purposes, and different groups value different aspects,” Pat explains. “Fishermen often want sufficient aquatic vegetation for a healthy fishery, while boaters and swimmers typically prefer little to no vegetation. The best way to ensure a balanced approach is to involve all stakeholders in the conversation.”

At Lake Hopatcong, Pat and his team work closely with the Lake Hopatcong Commission, Lake Hopatcong Foundation, local government entities, volunteers, and community members. Regular communication and engagement efforts ensure that project goals reflect the needs of the entire community. By fostering open dialogue, gathering feedback, and sharing scientific insights, they aim to inspire stewardship and long-term investment in the lake’s health.

Looking Ahead

As Pat continues to make meaningful contributions to Princeton Hydro’s mission, he remains dedicated to expanding his expertise and leadership in lake and watershed management. He thrives on the balance between technical fieldwork, client collaboration, and mentorship, and he’s always eager to take on new challenges in aquatic science.

For students interested in the field, Pat emphasizes the value of hands-on experience: “Take as many courses as you can in aquatics and related fields,” he advises. “Seek out internships, research opportunities, or assist graduate students and professors. Real-world experience is invaluable.”

With passionate professionals like Pat leading the way, the future of lake management and watershed restoration is in good hands.

Click here to read the previous "Day in the Life" blog series edition featuring Tara Srinivasan, Environmental Scientist and GIS Analyst, and stay tuned for more behind-the-scenes stories from our talented team!

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By Dr. Fred Lubnow, Senior Technical Director of Ecological Services

As we reflect on the winter of 2023-2024, it's evident that New Jersey experienced another unusually mild season, mirroring the winter of 2022-2023. Notably, Lake Hopatcong, located in Sussex and Morris Counties, remained virtually ice-free throughout the winter, with only a brief period of minor ice formation in early January. This pattern was not isolated to Lake Hopatcong; many lakes across the state and the broader Mid-Atlantic region exhibited similar ice-free conditions. Such conditions can lead to increased algal and plant growth earlier in the year.

Adding to this, from January to early June 2024, 15 of New Jersey's 21 counties recorded precipitation levels 26% to 50% higher than their long-term averages. The remaining six counties, predominantly in the southern part of the state, had precipitation increases of 11% to 25% above their long-term normals. This heightened precipitation is significant as it can transport nutrients, most notably phosphorus and nitrogen, into water bodies, potentially fueling the growth of algae.

Compounding these factors, long-range climate models and trends suggest that the summer of 2024 could rank among the hottest on record. The combination of a mild winter, increased precipitation, and anticipated high summer temperatures sets the stage for conditions similar to those experienced in 2019, a year marked by widespread harmful algal blooms (HABs) in numerous lakes.

HABs, characterized by rapid overgrowths of cyanobacteria, present serious challenges to water quality and aquatic ecosystems. Cyanobacteria, or blue-green algae, naturally occur in aquatic environments but can proliferate rapidly under warm, nutrient-rich conditions. These blooms pose risks to human health, wildlife, aquatic species, local economies, and the overall ecological balance. The interplay between climate change and HABs is undeniable: rising temperatures and altered precipitation patterns foster conditions that exacerbate bloom occurrences.

Given these circumstances, it is crucial for lake managers and water utilities to adopt proactive measures. Early and consistent sampling efforts can detect cyanobacteria and akinetes, dormant spores that contribute to bloom formation. Additionally, reducing nutrient inputs, particularly phosphorus, into waterways is essential to prevent HABs. Princeton Hydro strongly recommends that lake managers, water utilities, and concerned community members closely monitor their lakes, reservoirs, and riverways to stay as proactive as possible in managing these valuable resources.

By raising awareness, fostering collaboration, and implementing effective strategies, we can work towards safeguarding the health and sustainability of our freshwater ecosystems. Together, we can address the challenges posed by HABs and protect the integrity of our water bodies. For more information about HABs, click here.

Dr. Fred Lubnow, Princeton Hydro’s Senior Technical Director, Ecological Services, is an expert in aquatic and watershed management, restoration ecology, community and ecosystem ecology, and the use of benthic macroinvertebrate and fish in-stream bioassessment protocols. Dr. Lubnow has managed hundreds of lake projects and provides technical expertise for a variety of lake and watershed restoration projects.

His experience in lake and reservoir restoration includes the design and implementation of dredging, aeration, chemical control of nuisance species, nutrient inactivation (i.e. alum) and biomanipulation. His experience in watershed restoration includes the design and implementation of structural Best Management Practices (BMPs), the development of Total Maximum Daily Load (TMDL) pollutant budgets, and the design, implementation and analysis of watershed-based monitoring programs.

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We are thrilled to announce that Dr. Fred Lubnow, Senior Technical Director of Ecological Services at Princeton Hydro, has been honored with the prestigious Peter Homack Award by the American Water Resources Association, New Jersey Section (NJ-AWRA). The award was presented during NJ-AWRA’s annual meeting in December, recognizing Fred’s outstanding contributions to the multi-disciplinary understanding and management of New Jersey’s water resources.

The Peter Homack Award, established in 1987, commemorates the late Peter Homack, a former NJ-AWRA president and distinguished New Jersey engineer. The award celebrates individuals who exemplify Homack’s legacy of advancing water resource management through collaboration and innovation.

Fred’s selection for this honor is a testament to his decades-long dedication to the restoration and protection of water resources. Since Princeton Hydro’s founding in 1998, Fred has played a pivotal role in the study and restoration of hundreds of lakes across New Jersey and the Mid-Atlantic region. His work at Lake Hopatcong, in particular, stands as a shining example of his commitment. For over 30 years, Fred has partnered with Lake Hopatcong stakeholders to implement comprehensive restoration plans, develop best management practices, and achieve milestones toward the lake’s water quality goals.

Beyond his work at Princeton Hydro, Fred has enriched the field of water resource management through education and stewardship. He teaches watershed management at Delaware Valley University and freshwater ecology at Villanova University, inspiring the next generation of environmental stewards. Fred has contributed to NJ-ARWA over the last five years through a variety of presentations on harmful algal blooms (HABs) and watershed planning. Additionally, he has held leadership roles in the North American Lake Management Society (NALMS) and the Pennsylvania Lake Management Society. Selected as a member of the New Jersey Department of Environmental Protection’s HAB Expert Team, Fred has been instrumental in shaping the HAB advisory and alert systems we rely on today. His contributions have advanced our understanding of the factors driving cyanobacterial blooms in New Jersey’s lakes, offering valuable insights to improve the prediction, prevention, and management of these blooms.

Although Fred could not attend the award ceremony in person, he joined virtually via Zoom as his colleague Michael Hartshorne, Princeton Hydro’s Director of Aquatics, accepted the award on his behalf. During Michael's acceptance speech, he said:

“I’ve worked with Fred since I started at Princeton Hydro in 2006. He’s a humble leader, a dedicated mentor, and an overall fantastic person. Fred’s enthusiasm for lake ecology, particularly algae, is truly infectious. It’s a rare skill to make others genuinely excited about such a niche topic, but Fred has a remarkable way of doing just that. Fred truly embodies the spirit of the Peter Homack Award, and it’s an honor to receive this on his behalf.”

Fred’s passion, expertise, and collaborative spirit have left an indelible mark on water resource management in New Jersey and beyond. Princeton Hydro congratulates him on this well-deserved recognition and looks forward to his continued contributions to the field.

Earlier this year, Fred wrote a piece on "Preparing for Potential Harmful Algal Blooms: An Urgent Call to Action for NJ’s Lakes and Reservoirs." Click here to read it and learn more about his work to address the challenges posed by HABs and protect the integrity of our water bodies. [gallery link="none" ids="16058,4919,2956"] [post_title] => Princeton Hydro’s Dr. Fred Lubnow Receives NJ-AWRA's Peter Homack Award [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => princeton-hydros-dr-fred-lubnow-receives-nj-awras-peter-homack-award [to_ping] => [pinged] => [post_modified] => 2025-03-26 23:50:52 [post_modified_gmt] => 2025-03-26 23:50:52 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=16054 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [5] => WP_Post Object ( [ID] => 13355 [post_author] => 1 [post_date] => 2023-08-16 07:03:24 [post_date_gmt] => 2023-08-16 07:03:24 [post_content] =>

400 native plants were installed along the western shoreline of Memorial Pond in Mount Arlington, New Jersey. The planting was completed in one day by a team of 20+ volunteers, staff members from Mt. Arlington Department of Public Works (DPW), Lake Hopatcong Foundation, Lake Hopatcong Commission, Princeton Hydro, and a generous community member who volunteered his excavating equipment (and time).

The planting initiative aims to prevent shoreline erosion, promote the growth of native species, increase wildlife habitat, and improve the water quality of Memorial Pond and Lake Hopatcong. Funding for this project was secured through a grant from the New Jersey Department of Environmental Protection, awarded to the Lake Hopatcong Commission in partnership with the Lake Hopatcong Foundation.

[caption id="attachment_13422" align="aligncenter" width="616"]

Photo by Lake Hopatcong Foundation Executive Director Kyle Richter[/caption]

Memorial Pond

Memorial Pond is a 0.3-acre stormwater runoff basin that gradually releases into Glen Brook, which then flows into Lake Hopatcong. The pond receives sheet flow of stormwater from the adjacent road, which contributes to nutrient and sediment loading, thus locally reducing water quality in Memorial Pond and ultimately the waters of Lake Hopatcong.

Memorial Park, which includes Memorial Pond and Glen Brook, was identified by Princeton Hydro and the Lake Hopatcong team as a priority site for improvement, targeting initiatives that reduce pollutants and excessive nutrients entering into Lake Hopatcong.

Additionally, the pond’s steeply-sloped shoreline was bare and only stabilized with large rocks at the base of the banks. In the absence of stabilizing vegetation, the pond’s banks were experiencing erosion, and there was some concern about a few mature trees along the shoreline potentially falling into the pond.

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The photos above were taken in April 2023 before the planting initiative.

Shoreline Planting Initiative

The plant selection and layout were designed taking into account the steep slope and presence of mature, existing trees as well as focusing on regionally native plant species that will thrive and help stabilize the eroding shoreline. The planting team, led by Princeton Hydro Landscape Architect Jamie Feinstein, RLA and Aquatics Project Manager Pat Rose, was given precise instructions on how to install the plants to eliminate washouts and ensure the root systems can embrace the soil and hold it in place.

A variety of native herbaceous plants and shrubs were chosen for the site, including pennsylvania sedge, slender mountain mint, blue flag iris, sweet azalea, smooth hydrangea, and maple-leaved viburnum.

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The plants will help reduce stormwater flow, absorb excess nutrients, prevent erosion, and ultimately decrease sedimentation to the pond, while creating a visually pleasing addition to the park and providing a habitat for pollinators and birds. Overall, this project promotes a healthier and more balanced ecosystem in Memorial Park.

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The photos above were taken in July 2023 immediately after the planting initiative.

Multi-Faceted Approach to Water Quality Improvements

The installation of these beneficial plants is part of a series of water quality initiatives on Lake Hopatcong funded by a NJDEP Freshwater Harmful Algal Bloom (HAB) Prevention & Management Grant and 319(h) Grant awarded to Lake Hopatcong Commission in partnership with the Lake Hopatcong Foundation.

Additional initiatives included in the watershed implementation and HABs management plan are, the installation of:

floating wetland island (FWI), which are a low-cost, effective green infrastructure solution designed to mimic natural wetlands in a sustainable, efficient, and powerful way. FWIs 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;
biochar filtration bags, which improve water quality by removing phosphorus from waterbodies. Biochar can be placed in floatation balls, cages, or sacks, which are then tethered along the shoreline and in critical locations throughout the waterbody; and
nanobubble aeration system, which increases the concentrations of dissolved oxygen in the water, prevents stagnation of water, increases circulation, disrupts thermal stratification which provides “through-column” mixing, and minimizes the occurrence of HABs.

“Paired with biochar filters attached to buoys in the pond and continued monitoring and maintenance of the plantings by the DPW, these steps will set a healthy precedent for what can be achieved through working together with funders, local partners, science, and landscape architecture,” said Feinstein, who sourced plant material, provided logistics and co-led the planning and volunteer planting event along with Rose.

Princeton Hydro's Landscape Architect, Cory Speroff PLA, ASLA, CBLP, designed the planting plan, and Will Kelleher and Jackson Tilves from the Aquatics Team participated in the plant installation event with Feinstein.

Princeton Hydro is also authoring and supplying a maintenance manual that provides guidance on seasonal care of the plantings, when to remove the herbivory protection fencing, pruning, watering, and other activities that support the long term success of the planting initiative.

“This collaborative effort to enhance water quality serves as a prime example of how seemingly simple actions can have a meaningful impact on safeguarding our water resources for the benefit of future generations,” said the Lake Hopatcong Foundation.

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The photos above from left to right: June 2023 before the planting; July 2023 during the planting (photo by Lake Hopatcong Foundation Executive Director Kyle Richter); and July 2023 immediately after the planting.

Princeton Hydro has been working on 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. To read about some of the other projects we’ve recently worked on at Lake Hopatcong, click here.

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This article, written by Princeton Hydro team members, was recently published in the ANJEC Report, a quarterly magazine published by the Association of New Jersey Environmental Commissions.

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.

[caption id="attachment_4363" align="aligncenter" width="631"] This illustration, created by Staff Scientist Ivy Babson, conveys the functionality of a Floating Wetland Island

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

This illustration, sketched by Princeton Hydro Staff Scientist Ivy Babson, conveys the functionality of a floating wetland island.[/caption]

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.

Let's take a look at some examples of FWIs in action:

Lake Hopatcong

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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.

Greenwood Lake

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.

Harveys Lake

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.

Wesley Lake and Sunset Lake

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.

- *U.S. Environmental Protection Agency. 2008. Handbook for Developing Watershed Plans to Restore and Protect Our Waters.

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Harveys Lake, Luzerne County, PA in February 2023 (Photo by Jason Miller)[/caption] By Dr. Fred Lubnow, Senior Technical Director of Ecological Services

The Winter of 2022 – 2023 is turning out to be a mild one, at least in the Mid-Atlantic region of the United States. Anecdotally, there has been no measurable amount of snowfall in 2023 as of early March. In northeastern Pennsylvania, January and February 2023 mean monthly temperatures were 9.6 and 7.5 degrees warmer relative to their long-term respective average values. In northern New Jersey, January and February 2023 mean monthly temperatures were 11.9 and 5.6 degrees warmer relative to their respective long-term average values (Northeast Regional Climate Center CLIMOD database).

[caption id="attachment_12421" align="alignleft" width="239"]

Lake Hopatcong, Sussex – Morris Counties, NJ (Photo by Donna Macalle-Holly, Lake Hopatcong Foundation)[/caption]

This has had a profound impact on lake ecosystems. For example, in early 2023, both Harveys Lake (Luzerne County, PA) and Lake Hopatcong (Morris and Sussex Counties, NJ) have had no lake-wide ice cover. While measurable amounts of both snowfall and ice cover are still possible in the remaining weeks of March, it highly unlikely that such conditions would persist for weeks. Such ice-free conditions on our lakes, ponds and reservoirs will certainly have a profound impact on these ecosystems as we move into the 2023 growing season.

Algae May Grow Earlier in the Season

Undoubtably, current conditions are at a minimum partially attributed to climate change and will have a direct impact on the upcoming 2023 growing season. In the absence of ice, and more importantly snow-cover over the ice, aquatic plants and algae can begin to grow earlier in the season. Some plants, such as the invasive species curly-leaved pondweed (Potamogeton crispus), prefer cooler temperatures and tend to attain their highest densities in the spring and early summer. However, under such ice-free conditions, we have seen curly-leaved pondweed growing along the bottom of New Jersey lakes as early as February. This can result in more nuisance plant densities earlier in the year.

While most cyanobacteria, the group of algae known to have the potential to produce cyanotoxins, tend to attain their maximum growth and biomass over the hot summer months, there are several genera that are more tolerant of cool temperatures. For example, one filamentous genus, Aphanizomenon, is one of the first cyanobacteria to appear in the plankton in the spring. Indeed, over the last few years Aphanizomenon has been appearing earlier in the year and at higher densities in many of the lakes monitored and managed by Princeton Hydro. Another cyanobacteria known to bloom in cooler waters is Coelosphaerium. Coupled with slightly warmer temperatures over the late winter and early spring, cyanobacteria blooms could become more common and larger in magnitude, earlier in the year. Such blooms are frequently called Harmful Algal Blooms (HABs).

Many cyanobacteria produce resting spores called akinetes during conditions of environmental stress, such as colder temperatures and desiccation. These akinetes settle to the bottom and are re-activated as water temperatures increase. Warmer late winter and early spring temperatures, particular over the sediments, could mean more akinetes actively growing into vegetative cells earlier in the growing season.

Milder Winters Could Lead to New Invasive Species

[caption id="attachment_12439" align="alignright" width="476"]

At a lake in Somerset County on March 7, 2023, Spirogyra (a green mat algae that prefers cold waters) is present and curly-leaved pondweed is already growing and well established. Photo by Princeton Hydro.[/caption]

Last year (2022), was the first time that the cyanobacteria Cylindrospermopsis was identified in Lake Hopatcong. In fact, this genus was the most abundant cyanobacteria in Lake Hopatcong during our July and August sampling events, but was no longer found by the early October sampling event. The Cylindrospermopsis found in Lake Hopatcong may be an invasive species that historically has been found in tropic and subtropic waterbodies. However, over the years, this cyanobacterium has been found in temperate waterbodies. Milder and warmer winters may mean more invasive species such as Cylindrospermopsis appearing in Mid-Atlantic waterbodies.

What Should You Do?

In the absence of ice and snow-cover to put the sediments in the dark and prevent photosynthesis, coupled with warmer temperatures in the late winter and early spring, may lead to more aquatic plant and algal growth earlier in the year. So what should be done about this?

1. Sample Early: March or April

First, we recommend initiating sampling earlier in the year, sometime in March or April; do not wait until May to begin sampling. Second, in addition to sampling the surface waters, sampling should also be conducted in near-shore areas, immediately above sediments and at the sediment-water interface. Samples should be examined under the microscope for the presence of akinetes and/or inactive colonies of cyanobacteria. Third, near-shore areas should also be surveyed for the presence of submerged, aquatic plants, in particular invasive species such as curly-leaved pondweed or hydrilla.

2. Encourage Residents to Reduce Nutrients Entering the Waterway

Finally, while most climate models indicate that HABs will more than likely increase in warmer conditions, the magnitude of this response will be strongly dependent on the availability of nutrients, in particular phosphorus. While phosphorus will drive the growth of cyanobacteria, the availability of external sources of nitrogen can increase the probability of a HAB producing cyanotoxins such as microcystins, which is a nitrogen “heavy” molecule.

Thus, if colonies of cyanobacteria or akinetes are found in the sediments over the spring, the lake community and stakeholders should be informed and efforts should be implemented to reduce the availability of nutrients such as using non-phosphorus fertilizers, picking up pet wastes, goose management, routine pump-outs of septic systems once every three years, where possible stabilize exposed soil by planting native vegetation and consider the use of green infrastructure such as rain gardens. By letting the community know that cyanobacteria may be lurking on the sediments over the spring season, it may mobilize efforts to implement both in-lake and watershed measures to minimize the potential development of HABs.

Princeton Hydro provides pond and lake management and monitoring services to hundreds of waterbodies in the Northeast. If you would like to learn more about our services for your community, please send us a message through our website.

Dr. Fred Lubnow, Princeton Hydro's Senior Technical Director, Ecological Services, is an expert in aquatic and watershed management, restoration ecology, community and ecosystem ecology, and the use of benthic macroinvertebrate and fish in-stream bioassessment protocols. Dr. Lubnow has managed hundreds of lake projects and provides technical expertise for a variety of lake and watershed restoration projects.

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This article was originally published in the Musconetcong Watershed Association's "Instream Update" eNewsletter.

The Musconetcong River begins at New Jersey’s largest lake, Lake Hopatcong, and flows southwest for 42 miles before emptying into the Delaware River. At the headwaters in Lake Hopatcong, the community has been battling with harmful algal blooms (HABs). HABs can cause significant water quality issues in lakes and ponds, often forming a visible and sometimes odorous scum on the surface of the water. Blooms are primarily caused by warmer temperatures and increased amounts of nutrients (i.e., nitrogen and phosphorus) from stormwater runoff.

In 2019, the local community suffered immensely from HABs, which was the most prolific bloom the lake has experienced over the last two decades, resulting in public health advisories to be issued for recreation on the lake. Because Lake Hopatcong is a popular summer vacation destination, this outbreak unfortunately stunted the local economy, restricted recreational usage of the lake, and impacted fish and wildlife.

The Lake Hopatcong Commission and Lake Hopatcong Foundation, in partnership with municipalities, counties, the state, local groups like the Musconetcong Watershed Association, and Princeton Hydro, have been working to improve water quality for years by prioritizing stormwater mitigation and septic management policies within the watershed. So why was the summer of 2019 so intense?

Analysis of 30 Years Water Quality Data

Princeton Hydro scientists have been collecting water quality data in Lake Hopatcong for 30 years. This includes dissolved oxygen, pH, and temperature, as well as concentrations of total suspended solids, total phosphorus, nitrate‐N, ammonia‐N and chlorophyll a, and various biological factors. There are not many lakes in New Jersey that have such a robust and consistent public dataset, which presents a rare opportunity to study long-term trends. We dove a little deeper into this information to see what many have caused the 2019 blooms.

We analyzed a statistically significant dataset of surface water temperatures and found that average July surface temperatures in Lake Hopatcong have been steadily increasing over time. We also have 20+ years of observational data that documents an increase in frequency, duration, and magnitude of HABs over the same time period. In fact, HABs have recently persisted all the way into the winter months, enabling “green ice” to form on the lake surface, as observed in December 2020.

In summer of 2019, the Lake Hopatcong region was hit with a dramatic amount of rainfall. These weather patterns resulted in some of the highest early summer total phosphorus (TP) concentrations in Lake Hopatcong in over 20 years. The mean June TP concentration was 0.043 mg/L; the last time it exceeded 0.04 mg/L was in 1999. In order to have acceptable water quality conditions in the lake, the mean TP concentrations should be at 0.03 mg/L or lower.

It has been well documented that phosphorus is the primary limiting nutrient in Lake Hopatcong. Meaning, a slight increase in phosphorus can result in a substantial increase in algal and/or aquatic plant biomass. The water quality analysis identified the cause for the HABs (the high frequency of storms in June 2019 transporting nutrients, in particular phosphorus, to the lake) and identified why they persisted over the growing season (internal phosphorus loading).

Climate Change as a Driver for HABs

Climate change is leading to more frequent, more intense rainstorms that transport run-off pollutants into waterways, coupled with hotter days to warm the water. The latest Intergovernmental Panel on Climate Change (IPCC) report, “AR6 Climate Change 2021: The Physical Science Basis,” confirmed that human influence has warmed the atmosphere, ocean, and land, and that this human-induced climate change is already affecting many weather and climate extremes in every region across the globe. It predicts, “increases in the frequency and intensity of hot extremes, marine heatwaves, and heavy precipitation, agricultural and ecological droughts in some regions, and proportion of intense tropical cyclones, as well as reductions in Arctic sea ice, snow cover and permafrost.” In the Mid-Atlantic region of the U.S., most climate models indicate that the landscape will become warmer and wetter.

Looking at our observations and 30-year dataset for Lake Hopatcong, our preliminary analysis shows that climate change — increased precipitation (which flushed the phosphorus into the lake) followed by intense heat to warm surface water temperatures — was a significant variable that led to the devastating HABs at Lake Hopatcong in 2019.

Other communities have experienced similar trends too. According to the U.S. Environmental Protection Agency, HABs have now been observed in all 50 states, ranging from large freshwater lakes, to smaller inland lakes, rivers, and reservoirs. Our neighbors in Upstate New York suffered from 1,000+ HAB occurrences during the 2019 season, including a HAB that covered 600+ square miles of Lake Erie causing beach closures and fish kills.

A study recently published in Nature journal reviewed three decades of high-resolution satellite data for 71 large lakes globally and determined that “peak summertime bloom intensity has increased in most (68%) of the lakes studied, revealing a global exacerbation of bloom conditions.” The study called for water quality management efforts to better account for the interactions between climate change and local hydrological conditions.

We are witnessing these impacts firsthand at Lake Hopatcong and within the Musconetcong River Watershed. And, according to the IPCC report, these climate change-induced instances (i.e. intense rainfall followed by intense heat) may become even more frequent. To further understand the connection between climate change and HABs at Lake Hopatcong, Princeton Hydro is conducting a more rigorous study that includes more distinct data. We hope this will provide some insight on how to manage expected climate impacts in lakes and watersheds.

Taking Action in the Musconetcong River Watershed

While the IPCC report conclusions may be depressing, there is still much we can do at both a global and local level to limit future climate change. The key here is limiting cumulative CO2 (carbon dioxide) and CH4 (methane) emissions and quickly reaching (at least) net zero CO2 emissions. And, to specifically reduce occurrences of HABs While the IPCC report conclusions may be depressing, there is still much we can do at both a global and local level to limit future climate change. The key here is globally limiting cumulative CO2 (carbon dioxide) and CH4 (methane) emissions and quickly reaching (at least) net zero CO2 emissions. And, to specifically reduce occurrences of HABs fueled by climate change in Lake Hopatcong, eliminating sources of phosphorus from entering the lake is critical. So what can we do in the Musconetcong River Watershed?

In 2019, NJ Department of Environmental Protection committed $13.5 million via their Water Quality Restoration Grant programs for local projects that aim to improve water quality in New Jersey’s lakes and ponds. The Lake Hopatcong Commission landed a $500k grant via the program to evaluate and implement a variety of innovative, nearshore projects at Lake Hopatcong. Projects included performing an alternative non-copper-based algaecide treatment and one of the largest nutrient PhosLock treatments in the Northeast on the lake as well as the installation of Biochar bags, near-shore aeration systems, and floating wetland islands.

This could not be possible without the help of all project partners including Lake Hopatcong Foundation, Morris County, Sussex County, Jefferson Township, Borough of Hopatcong, Borough of Mt. Arlington, and Roxbury Township, who collectively contributed over $330k in match support. The Lake Hopatcong Commission also landed a subsequent $206,000 grant via NJDEP’s 319 program a few months later, with $44,000 in match support from the four municipalities and Lake Hopatcong Foundation and Commission, for the design and implementation of four in-lake/watershed projects to protect Lake Hopatcong's water quality.

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The results of these projects were significant. Over the last two years, the mean June TP concentrations were lower than 2019 (0.033 mg/L in 2020 and 0.020 mg/L in 2021). These in-lake and watershed efforts have had a positive impact on reducing available phosphorus.

Just this month, Lake Hopatcong Commission landed another $480k from a National Fish and Wildlife Foundation Delaware Watershed Conservation Fund grant, which was backed with $489k more in match support from Lake Hopatcong Commission, Lake Hopatcong Foundation, Musconetcong Watershed Association, NJDEP, Borough of Hopatcong, Township of Roxbury, Mount Arlington Borough, Morris and Sussex Counties, Lake Hopatcong Historical Museum, Rutgers University, NJ Highlands Council, and Princeton Hydro. The project team will design and implement three streambank stabilization projects in the watershed, which were identified as priority projects in the 2021 Upper Musconetcong River Watershed Implementation Plan.

“Managing loads of phosphorous in watersheds is even more important as the East Coast becomes increasingly warmer and wetter thanks to climate change. Climate change will likely need to be dealt with on a national and international scale. But local communities, groups, and individuals can have a real impact in reducing phosphorous levels in local waters.”
Dr. Fred Lubnow, Director of Aquatics for Princeton Hydro

To read the full article in the Musconetcong Watershed Association's "Instream Update" eNewsletter, click here.

The Musconetcong Watershed Association is an independent, non-profit organization dedicated to protecting and improving the quality of the Musconetcong River and its watershed, including its natural and cultural resources. Since 2003, Princeton Hydro has been working with MWA in the areas of river restoration, dam removal, and engineering consulting. Click here to read our Client Spotlight blog featuring MWA’s Executive Director Cindy Joerger and Communications Coordinator Karen Doerfer.

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We are proud to announce that Princeton Hydro Aquatics Director Dr. Fred Lubnow and Founding Principal and Consultant Dr. Steve Souza have been appointed to the New Jersey HAB Expert Team as part of Governor Phil Murphy’s plan to enhance scientific expertise around water quality management and bolster the State's response to HABs.

The 10-person team, consisting of certified lake managers and cyanobacteria experts, will provide guidance to the New Jersey Department of Environmental Protection (NJDEP) on HAB prevention, treatment, and management for waterways throughout the state. The team is tasked with developing documents on best management practices; reviewing any proposed mitigation plans and technologies; reviewing water-quality data; and preparing a training workshop for NJDEP staff and stakeholders.

HABs are rapid, large overgrowths of cyanobacteria. These microorganisms are a natural part of aquatic ecosystems, but, under the right conditions (primarily heavy rains, followed by hot, sunny days), these organisms can rapidly increase to form cyanobacteria blooms. HABs can cause significant water quality issues, produce toxins that are incredibly harmful (even deadly) to humans, animals, and aquatic organisms, and negatively impact economic health, especially for communities dependent on the income of jobs and tourism generated through their local lakes. By appointing a team that will work solely on HABs in the state, New Jersey is taking proactive steps to combat the spread.

Dr. Fred Lubnow is Princeton Hydro’s Director of Aquatic Resources. His vast expertise includes aquatic and watershed management, restoration ecology, and algae ecology. He is regionally recognized as a HABs expert as he has provided management recommendations and services for over 100 lakes and ponds in the Northeast, including Lake Hopatcong, New Jersey’s largest lake.

“I believe the knowledge and experience I have gained over the last 27 years as an environmental consultant will be useful in addressing questions and problems associated with HABs and lake management in general. I look forward to contributing any way I can in addressing issues associated with HABs and lake management in New Jersey.”

Dr. Steve Souza, whose 30-year career has been dedicated to the restoration of lakes and ponds, is a founding principal of Princeton Hydro and nationally recognized lake expert and consultant.

“Over the past decade the public has become increasingly aware of HABs and the health and ecological impacts caused by HABs. Unfortunately HABs and the problems caused by HABs are not going away; they are only expected to get worse due to climate change related effects on storm events, increases in air and water temperature, and an expansion of the algal growing season. It is thus important for us to learn more about what drives HABs as well as the most successful and sustainable means of avoiding, controlling and mitigating HABs. I am very excited to be part of the NJ Sea Grant HAB Expert Team. Through this very knowledgeable group of scientists, educators, and lake managers we hope to learn more about the causes of HABs and even more about what we can do to prevent or lessen their occurrence.”

The full HAB Expert Team includes:

Jason Adolf, Monmouth University
Chris Doyle, Naiad Consultants
Nicole Fahrenfeld, Rutgers University
Jennifer Graham, USGS
Bob Kortman, Ecosystem Consulting Service
Fred Lubnow, Princeton Hydro
Ling Ren, George Mason University
Nathan Ruhl, Rowan University
Steve Souza, Clean Waters Consulting
Meiyin Wu, Montclair State University

All of us at Princeton Hydro are looking forward to seeing the work the expert team will undertake to improve the health, quality, and safety of New Jersey’s precious waterbodies. And, we extend a big congratulations to Fred, Steve and all other experts appointed to the team!

...

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[caption id="attachment_18637" align="aligncenter" width="1380"]

Photo by the Lake Hopatcong Commission[/caption]

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Home Blog

Tag: Lake Hopatcong

Posted on November 10, 2025 by Princeton Hydro

1. The Watershed Institute – Watershed-Based Planning for Assunpink Creek

2. Lake Hopatcong Commission – Watershed-Based Stormwater BMPs

3. Cozy Lake, Jefferson Township – Addressing Emerging Contaminants

4. Rockaway Township – Watershed-Based Green Infrastructure

5. Green Trust Alliance – Green Infrastructure and Community Engagement

Preparing Equipment and Safety Gear for a Day in the Field

On the Water: Conducting Water Quality Monitoring in the Field

Exploring Lake Hopatcong: A Case Study in Trout Habitat Monitoring

Building Partnerships for a Thriving Lake

Looking Ahead

By Dr. Fred Lubnow, Senior Technical Director of Ecological Services

Memorial Pond

Shoreline Planting Initiative

Multi-Faceted Approach to Water Quality Improvements

This article, written by Princeton Hydro team members, was recently published in the ANJEC Report, a quarterly magazine published by the Association of New Jersey Environmental Commissions.

Let's take a look at some examples of FWIs in action:

Lake Hopatcong

Greenwood Lake

Harveys Lake

Wesley Lake and Sunset Lake

Algae May Grow Earlier in the Season

Milder Winters Could Lead to New Invasive Species

What Should You Do?

1. Sample Early: March or April

2. Encourage Residents to Reduce Nutrients Entering the Waterway

This article was originally published in the Musconetcong Watershed Association's "Instream Update" eNewsletter.

Analysis of 30 Years Water Quality Data

Climate Change as a Driver for HABs

Taking Action in the Musconetcong River Watershed

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