The removal of Paulina Lake Dam marks a significant step in restoring the Paulins Kill River. With the spillway demolished, dredging completed, and the trail bridge stabilized as of October 2024, the transformation has been remarkable. A new project video now captures this rapid evolution and celebrates the remarkable progress made.

Watch the Latest Project Video

We invite you to watch the new video documenting the removal process for the Paulina Lake Dam. The video's captivating aerial footage, taken by The Nature Conservancy (TNC) Volunteer Drone Team before demolition and by Princeton Hydro throughout and after the removal process, showcases the dramatic transformation of the site. The video walks viewers through each removal phase—from initial notching to full demolition—while highlighting what’s next in the ongoing Paulins Kill River restoration effort.

Click below to watch it now: [embed]https://www.youtube.com/watch?v=VDbe6oUPEOI[/embed]

A Legacy of Connectivity and Restoration

The removal of Paulina Lake Dam is part of a broader effort to restore the Paulins Kill River and its ecosystem. Since 2019, four dam removals—including Columbia Lake’s remnant and main dams (2019), County Line Dam (2022), and Paulina Lake Dam (2024)—have reconnected 45 miles of river habitat, allowing native species like brook trout and migratory fish to thrive.

Beyond enhancing aquatic and terrestrial connectivity, the dam’s removal mitigates safety hazards, improves water quality, and expands recreational opportunities for the community. It also contributes to ongoing wetland and riparian zone restoration, including the reforestation of the floodplain and protection of critical habitats.

What’s Next?!

While the dam is gone, restoration efforts are not quite over. In early Spring, the project team will initiate the third and final project phase by visiting the site to assess and plan for adaptive management work, which will commence in July 2025. During this final push, the project team will enhance habitat features, stabilize riverbanks in select locations, and plant native trees, ensuring a thriving ecosystem for years to come. Stay tuned for more updates as we continue to witness the transformation of the Paulins Kill.

Each year on March 3rd, World Wildlife Day offers an opportunity to celebrate the incredible biodiversity of our planet and raise awareness about the importance of protecting and restoring critical habitats. In that spirit, we’re highlighting a transformative project that turned degraded wetlands into a thriving wildlife sanctuary: The Pin Oak Forest Stream, Wetland, and Upland Enhancement Project in Woodbridge, New Jersey, stands as a testament to the power of restoration and the lasting impact of ecological stewardship.

Restoring Vital Habitat in a Developed Landscape

Located in a highly developed region of Middlesex County, the Pin Oak Forest Conservation Area is a rare ecological gem—a 97-acre open space containing a critical wetland complex at the headwaters of Woodbridge Creek. Before restoration efforts began, the area suffered from habitat fragmentation, wetland degradation, and the encroachment of invasive species, all of which had significantly reduced biodiversity and threatened native wildlife.

Recognizing the urgency of intervention, a diverse coalition of government agencies, NGOs, and private industry, including Middlesex County Office of Parks and Recreation, Woodbridge Township, Woodbridge River Watch, New Jersey Freshwater Wetlands Mitigation Council, GreenTrust Alliance, GreenVest, and Princeton Hydro, came together to design and implement a comprehensive restoration plan aimed at revitalizing the area’s natural functions.

The project converted nearly 29 acres of degraded wetlands, over 1,000 feet of channelized streams, and disturbed uplands into a vibrant, species-rich ecosystem. By reconnecting the stream to its floodplain and incorporating microtopography techniques, the restoration team created a varied landscape that supports multiple habitat communities and improves groundwater infiltration—essential elements for sustaining wildlife.

[gallery link="none" size="medium" ids="7282,7268,7258"]

A Haven for Wildlife

The transformation of Pin Oak Forest into a high-functioning wetland complex has had profound impacts. The site now provides critical habitat for a range of species, including the state-threatened Black-crowned Night-Heron (Nycticorax nycticorax) and Red-headed Woodpecker (Melanerpes erythrocephalus). The reestablishment of native vegetation, such as pin oak (Quercus palustris), swamp white oak (Quercus bicolor), and swamp rose (Rosa palustris), has further enhanced the ecosystem, creating food sources and nesting areas for birds, amphibians, and pollinators.

[gallery link="none" size="medium" ids="17106,17107,17108"]

By managing invasive species and allowing native flora to flourish, biodiversity has significantly increased. The restored headwater wetland system supports a delicate balance of aquatic and terrestrial life, creating a vital refuge for countless species amid an otherwise urbanized landscape.

This success story highlights how thoughtful ecological restoration can bring degraded environments back to life, providing a lasting benefit for wildlife and the surrounding community alike.

Continuing the Commitment to Wildlife Conservation

On this World Wildlife Day, the Pin Oak Forest project serves as an inspiring reminder of what’s possible when partnerships, science, and dedication converge to protect and restore critical habitats. The work done here is not just about the past—it’s about shaping a future where wildlife and people can thrive together.

At Princeton Hydro, we remain committed to advancing ecological restoration, ensuring that more landscapes like Pin Oak Forest can be revitalized for generations to come. We hope that by reflecting on the success of this project, more communities and organizations will be inspired to take action in preserving and restoring the natural world and pledge to protect the wildlife that makes our planet so extraordinary.

To learn more about the award-winning Pin Oak project and see additional restoration photos, click here.

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Rivers are the lifeblood of ecosystems, weaving through landscapes to connect habitats, sustain biodiversity, and provide vital resources to communities. Yet, rivers around the world are disrupted by outdated dams, weirs, culverts, and other blockages that fragment habitats, block fish migration, and degrade ecological health. The consequences are far-reaching, threatening not only ecosystems but also the communities that depend on healthy rivers.

Research by the European Open Rivers Programme has highlighted both the urgent need for action and the immense potential of dam removal to restore ecosystems, improve biodiversity, and revive natural river connectivity.

Since 2022, Princeton Hydro President and Principal Geoffrey M. Goll, PE — an expert in water resources engineering — has been collaborating with organizations in Portugal to advance shared goals of river restoration and ecosystem revitalization. In October 2024, Mr. Goll traveled to Portugal, where he met with the organizations driving forward the country’s ecosystem restoration efforts and visited the sites of three key projects he has, or is currently collaborating on.

This blog explores those restoration efforts, highlighting how they address the challenges of river fragmentation while establishing a blueprint for future restoration efforts.

Galaxes Weir Removal: A Groundbreaking First for Portugal

One of the most significant examples of these collaborative restoration efforts is the groundbreaking Galaxes Weir Removal project, which set the stage for future initiatives by addressing river fragmentation on Portugal’s Odeleite River.

Galaxes Weir Removal project in Portugal's Algarve Region marked the country’s first civil removal of an obsolete river barrier to benefit migratory fish species. Associação Natureza Portugal in association with World Wildlife Fund Portugal (ANP/WWF), a non-profit NGO dedicated to the conservation of nature and the protection of the planet, reached out to Mr. Goll and Ms. Lisa Hollingsworth-Segedy of American Rivers, to undertake this pioneering effort.

Completed in March 2023, the removal of the 2-meter-high Galaxes Weir restored 7.7 kilometers of river connectivity, aiding in the preservation of critical fish species such as the Spanish minnowcarp (Anaecypris hispanica) and the critically endangered European eel (Anguilla anguilla). By improving river flow and ecological conditions, the project also bolstered economically vital fisheries, enhanced recreational opportunities, and supported local tourism, establishing a model for future restoration initiatives. Funding for the Galaxes Weir removal was provided by the European Open Rivers Programme (EORP), a grant-giving organization dedicated to restoring European rivers. The international partnership that brought Mr. Goll and Ms. Hollingsworh-Segedy into the fold was facilitated by connections made through the World Fish Migration Foundation. He and Ms. Hollingsworth-Segedy were asked to provide guidance on the de-construction of this concrete structure.

[caption id="attachment_17074" align="aligncenter" width="593"]

During his trip in October 2024, Mr. Goll visited the Galaxes Weir removal project site to observe changes to the landscape since the project’s completion in March 2023.[/caption]

The success of the Galaxes Weir Removal project highlights the importance of both engineering knowledge and techniques, as well as community engagement. By involving local communities throughout the process, the project fostered a sense of shared responsibility and ensured that the ecological and cultural value of the river was preserved. It also underscored the benefits of dam removal as a swift and effective strategy to enhance biodiversity and promote sustainable river management.

The photos below, taken by ANP/WWF, depict the Galaxes Weir project site before, during, and after removal: [gallery link="none" size="medium" ids="17071,17069,17072"] Click here to see more photos, watch videos of the removal process, and read more detailed information about this groundbreaking project.

Perofilho Weir Removal: Establishing a Blueprint for River Restoration

Building on the success of the Galaxes Weir removal, the ANP/WWF team expanded its efforts to Santarém, Portugal, northeast of Lisbon, on the Perofilho Stream, a tributary of the Tejo River. The Perofilho Weir, a 2-meter-high concrete barrier, fragmented habitats and disrupted the natural flow of the stream. The National Authority for Nature and Forests Conservation (ICNF) identified the Galaxes Weir as one of the obsolete barriers to be removed to improve fish and overall biodiversity in the area and restore fluvial connectivity.

This restoration project, initiated in 2023, was led by ANP/WWF in collaboration with SOS Animal (weir owner) and the Santarém Municipal Council (local government). Mr. Goll was invited to design the removal of the concrete weir, including innovative solutions such as the use of live timber crib walls for stream bank stabilization. He also provided consultation to the onsite construction manager during the removal process and conducted a final site walkthrough following construction, offering recommendations to ensure long-term success.

The photos below, provided by EORP and by ANP/WWF, depict the Perofilho Weir project site before, during, and after removal: [gallery link="none" size="large" columns="2" ids="17076,17077"]

The Perofilho Weir removal, completed in October 2024, restored 2.2 kilometers of the Perofilho Stream—nearly half its total length—reconnecting it with the Tejo River. This comprehensive restoration project addressed sediment management, habitat rehabilitation, and flood risk reduction, resulting in significant improvements to water quality and ecological health. Key species benefiting from these efforts include the Eurasian otter (Lutra lutra) and the Iberian painted frog (Discoglossus galganoi). Notably, it also enabled the first research into fish species inhabiting the stream.

This milestone project not only revitalized a critical aquatic ecosystem, it also established a blueprint for future river restoration efforts in Portugal and beyond.

During Mr. Goll’s visit to Portugal in October 2024, he toured the Perofilho Weir removal site alongside Maria João Costa, Water Coordinator of ANP/WWF. Together, they participated in a live video event hosted by the World Fish Migration Foundation, celebrating the project’s success. Broadcasted on the Dam Removal Europe YouTube channel, the event highlighted the restoration effort’s impact on biodiversity and river connectivity. If you missed the live broadcast, the recording is available online. Watch now:

[embed]https://www.youtube.com/live/PzzDQ86hZZQ?si=GQrEqTPcQRmLKHep[/embed]

Oeiras River Restoration: A Comprehensive Plan for Connectivity

The Oeiras River in western Algarve winds through rural landscapes, agricultural zones, and small towns before merging with the Arade River. This intermittent Mediterranean stream supports native and endangered species and serves as a habitat for some of Portugal’s most iconic mammals.

[caption id="attachment_17061" align="aligncenter" width="681"]

Summer refuge pools on the Oeiras River[/caption]

Recognizing the river’s ecological significance, the ICNF identified it as a high-priority conservation area with potential for impactful restoration. In collaboration with the company Somincor, ICNF contracted ANP/WWF to evaluate the removal of nine barriers along the river, beginning with the upstream Horta Fialho Weir.

To complete the proposed work, ANP/WWF is undertaking several activities, including feasibility assessments, local community and stakeholder engagement, and public environmental education. ANP/WWF engaged Princeton Hydro to prepare the design and specifications for the Horta Fialho Weir removal and develop concept designs for the eight (8) additional barriers.

In October 2024, Mr. Goll spent a week in the field alongside ANP/WWF, surveying the Oeiras River and its tributaries, documenting blockages and ecosystem conditions, meeting with local dam owners and community members, and gathering field measurements to inform the designs and specifications.

[gallery link="none" size="large" ids="17091,17063,17093"]

The photos, kindly provided by Maria João Costa, Water Coordinator of ANP/WWF, show Mr. Goll and Ms. Costa in the field during the October 2024 survey of the Oeiras River and its tributaries.

The removal of the Horta Fialho Weir will reconnect 2.34 kilometers of the river and set the stage for removing the eight additional barriers, which would ultimately restore 143.4 kilometers of river connectivity. This ambitious initiative is expected to significantly enhance the river’s ecological health and improve habitats for native and endangered species, including freshwater mussels (Unio tumidiformis, Anodonta anatina, Unio delphinus), and their host fish (Squalius spp.), the migratory European eel (Anguilla anguilla), the Iberian lynx (Lynx pardinus), and the Eurasian otter (Lutra lutra).

Beyond ecological benefits, the project offers a unique opportunity to raise awareness about the advantages of dam removal and the critical importance of biodiversity conservation across Portugal. The European Open Rivers Programme is funding this landmark restoration effort.

Collaborating for a Sustainable Future

Portugal’s ecosystem restoration projects illustrate the impact of international collaboration and knowledge exchange. By removing barriers, reconnecting habitats, and revitalizing ecosystems, these efforts are paving the way for a healthier future for rivers and the communities that depend on them. Through continued partnerships and mutual support, the journey toward sustainable environmental stewardship remains hopeful and promising.

Building on the success of these initiatives, Mr. Goll and the Princeton Hydro team look forward to continuing their work in Portugal and beyond, offering technical expertise in ecosystem restoration and barrier removal to support similar efforts around the world.

[caption id="attachment_17065" align="aligncenter" width="620"]

Morning coffee and work session in Mertola, Portugal[/caption]

Acknowledgments: Celebrating the Power of Partnerships

This work would not be possible without the dedication of ANP/WWF, the European Open Rivers Programme, the Dam Removal Europe team, The National Authority for Nature and Forests Conservation, Herman Wanningen, and all the local landowners who were committed to the restoration of the Oeiras River. Their commitment to river restoration and biodiversity conservation serves as an inspiration, demonstrating the transformative power of collaboration and shared vision. We encourage you to click the links provided to learn more about these vital organizations.

Princeton Hydro has successfully designed, permitted, and overseen the removal of over 84 dams to date. Mr. Goll holds a B.S. in Civil Engineering from Rutgers University and a Master of Engineering Management from UW–Madison. His knowledge encompasses water resources and geotechnical engineering, including sediment management, stream and river restoration, stormwater management, green infrastructure, freshwater wetland and coastal marsh design, dam design, and dam removal. He is recognized as a distinguished leader in advancing innovative and effective solutions for river restoration.

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Welcome to our latest installment of the “A Day in the Life” blog series. Today, we delve into the fascinating world of Geographic Information Systems (GIS) analysis through the eyes of Tara Srinivasan. Tara, an environmental staff scientist for the Restoration & Resilience team and a GIS analyst, combines her passion for environmental research with the power of geospatial data to support sustainable projects that enhance ecosystems and communities alike.

GIS is a powerful technology used to study, analyze and visualize geospatial data. In Tara’s role at Princeton Hydro, GIS serves as both a creative and analytical tool, enabling her to generate and explore detailed maps of environmental conditions at project sites, such as vegetation, soils, topography, and water bodies. This process aids in identifying restoration needs, addressing challenges, and developing innovative solutions.

Let’s embark on a journey through a typical day in Tara’s role and uncover how her expertise helps shape Princeton Hydro’s environmental restoration projects.

Diving Into Data

Tara usually starts her day in the office, preparing to analyze data for a particular project. Using GIS software like ArcGIS, she examines historical and current imagery of the site, overlays habitat features, and maps property boundaries. These analyses help Tara and the project team understand the site’s existing conditions, such as watershed boundaries and the presence of threatened or endangered species.

“GIS allows us to study locations remotely, uncover patterns and features that might not be obvious on the ground, and understand how a place interacts with its surrounding environment,” Tara explains. “By incorporating extensive environmental data from local, state, and national resources - collected by both public and private organizations - I can gain a comprehensive view of a project site before we even set foot in the field.”

From calculating the impacts of a proposed restoration project to mapping flood conditions under various climate scenarios, Tara’s work ensures that Princeton Hydro’s environmental solutions are informed by robust spatial data and cutting-edge technology.

One project Tara is especially proud of is Princeton Hydro’s contribution to the Trenton Vulnerability Assessment, part of the Resilient NJ initiative administered by the NJDEP Bureau of Climate Resilience Planning. “We modeled flooding and urban heat islands based on current data and future projections of climate change, and created a mapping tool that overlaid hazard areas with Trenton’s critical facilities, community assets, cultural and ecological resources, and vulnerable populations,” she shares. Tara had the opportunity to present this data to Trenton residents, who shared their questions and ideas for solutions that the City incorporated into its climate planning efforts. “It was a great way to engage with our local Trenton community, get in-person feedback on our maps, and see the potential that GIS and environmental data have in informing social conversations,” Tara adds.

Delineating a Watershed

Today, Tara is focused on defining the boundaries of a watershed surrounding a small lake. In this video, she walks us through her step-by-step process for watershed delineation:

[embed]https://youtu.be/qPi_FvJRGcQ[/embed]

Collaborating Across Teams

Collaboration is a key part of Tara’s role. On a typical day, she meets with Princeton Hydro’s regulatory team to discuss GIS findings that inform project permitting and compliance. These partnerships enhance her work, ensuring that data analyses align with project goals and regulatory standards.

Tara also communicates her findings to clients and stakeholders who may not have technical GIS backgrounds. She uses intuitive maps, symbols, and colors—like blue for water and green for forests—to help stakeholders understand complex concepts at a glance. “Maps are a powerful thing,” Tara says. “They can bring people up to speed quickly and convey information in a way that words alone cannot.”

When maps become more intricate, Tara incorporates supplementary visuals, such as tables and graphs, to provide additional clarity. Her ability to bridge technical expertise with accessible communication is crucial for guiding clients through project decisions.

Fieldwork and Fresh Air

Although much of her work is office-based, Tara occasionally heads out into the field to collect data or monitor project sites. Equipped with GPS tools and field notebooks, she assesses topography, vegetation, and other site-specific details that feed back into her GIS analyses.

“Fieldwork provides a fresh perspective,” Tara notes. “It’s a great opportunity to see how projects are implemented and to observe how the environment evolves over time.”

Whether delineating watersheds or monitoring post-construction conditions, these outings connect Tara’s technical work to the tangible landscapes she aims to restore.

Overcoming Challenges with Innovation and Care

Tara thrives on finding innovative solutions to challenges in her work, such as optimizing software processes and addressing gaps in available data. Her meticulous organization of databases, attention to detail, and commitment to accuracy ensure that her outputs are both reliable and impactful. When data is limited, Tara ensures transparency by clearly communicating any uncertainties, fostering trust and confidence in her analyses.

Tara also approaches her work with a strong ethical lens, carefully considering the implications of GIS analyses on communities and ecosystems. “When you look at a map of a stream, lake, wetland, or forest in an urban area, it’s important to notice the houses, schools, businesses, parks, and other features that surround them,” Tara explains. “Our projects impact both the environment and people. GIS helps us examine a large area and assess our impact so we can minimize any temporary or permanent effects, both legally and ethically.” She notes that GIS can even identify already disturbed areas for construction access, helping preserve healthier habitats.

Continued Inspiration

Tara’s love for maps dates back to her childhood, when she was captivated by the intricate, hand-drawn maps in fantasy novels. Her fascination grew through exploring Google Earth, imagining future travels, and observing how geography shapes civilizations. This passion now drives her professional journey, where she uses GIS to merge her analytical skills with creativity. “I’ve always been a visual learner, so I find something grounding about orienting yourself on a map,” Tara shares.

When she’s not working, Tara enjoys wildlife photography hikes, baking experiments, and writing music for her ukulele—a testament to her creativity both inside and outside the office.

For Tara, GIS is more than a tool; it’s a gateway to understanding and addressing environmental challenges. Her work at Princeton Hydro highlights the versatility of GIS in projects ranging from wetland restoration to climate change resilience. Reflecting on her role, Tara says, “What I love most about GIS is its ability to bring environmental stories to life, helping people connect with the places they care about in a meaningful way.”

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Through her dedication and expertise, Tara embodies the spirit of innovation and environmental stewardship that defines Princeton Hydro’s mission.

Princeton Hydro’s multidisciplinary team combines unparalleled expertise with innovative geospatial technology to deliver integrated ecological and engineering solutions. From comprehensive assessments and sustainable design to implementation and community engagement, we are committed to addressing complex environmental challenges. Our team’s proven capabilities in natural resource management, water resources engineering, and geotechnical design—enhanced by in-house GIS expertise—enable us to provide tailored solutions that achieve measurable results. Whether conducting regional-scale analyses, developing coastal resiliency plans, or advancing ecological restoration efforts, we are proud to contribute to a sustainable future throughout the Northeast and beyond.

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An ambitious project is underway to eradicate the invasive Silty Pond Mussel (formerly known as the Chinese pond mussel, Sinanodonta woodiana) from the Wickecheoke Creek Preserve in New Jersey. This critical initiative seeks to protect local ecosystems, safeguard native aquatic species, and prevent the spread of these aggressive invaders into the broader Delaware River ecosystem.

[caption id="attachment_16006" align="alignright" width="394"]

Provided by NJ Conservation Foundation[/caption]

The Silty Pond Mussel was first discovered in the United States in 2010 at a former fish farm in Hunterdon County, now part of NJ Conservation Foundation’s Wickecheoke Creek Preserve. It is believed the mussels arrived as glochidia (a microscopic larval stage of some freshwater mussels) attached to the gills of bighead carp, another invasive species imported from China by the farm's previous owners. Initially overlooked and undocumented in North America, the mussels quickly established a foothold in the Preserve's ponds, threatening local ecosystems.

These invasive mussels, which can grow to the size of a small football, form high-density colonies that pose a severe threat to native organisms. This aggressive species outcompetes native mussels for nutrients and habitat, altering water chemistry in the process and drastically depleting the local ecosystem of resources essential to native plants and animals. Additionally, once the Silty Pond Mussel glochidia attach to the gills of native fish, a biological reaction occurs that ultimately kills the host fish thus preventing native mussels from completing their own life cycle on these fish hosts. This dual impact — monopolizing food and habitat resources as adults while denying native mussels access to necessary host fish — makes the Silty Pond Mussel especially harmful to local ecosystems.

Following the initial discovery, DNA testing conducted by the NJ Invasive Species Strike Team, New Jersey Endangered & Nongame Species Program, and the North Carolina State Museum of Natural Sciences confirmed the presence of this invasive species, marking the first documentation of the Silty Pond Mussel in North America. Early eradication efforts began shortly thereafter.

Since 2019, a coalition of partners has expanded these efforts and remained committed to the complete eradication of the Silty Pond Mussel species. Led by NJDEP Fish & Wildlife and including organizations such as tthe U.S. Fish & Wildlife Service, NJ Conservation Foundation, Rutgers University, NJ Water Supply Authority, U.S. Department of the Interior's Office of Restoration and Damage Assessment (ORDA) and Princeton Hydro, the project has focused on surveying waterways using SCUBA, snorkel and physical analysis; utilizing environmental DNA (eDNA) testing to detect the presence of mussels in a waterbody; and applying targeted treatments. Community engagement and education are also central to these efforts, emphasizing the importance of collaboration in tackling this ecological threat.

Geoffrey M. Goll, P.E., President of Princeton Hydro, emphasized the collaborative nature of the efforts: "This initiative exemplifies the power of partnership and innovation in tackling environmental challenges. Together, we are making significant strides in preserving our state's rich biodiversity."

Protecting Biodiversity and Partnering for Eradication

The Wickecheoke Creek Preserve, home to nearly 400 native plant species and a wide variety of wildlife, includes 14 miles of streams and flows directly into the D&R Canal, which supplies clean drinking water to one million New Jersey residents. New Jersey is also home to 12 native freshwater mussel species, nine of which are classified as Endangered, Threatened, or of Special Concern, further underscoring the the urgency of preventing this aggressive invasive species from spreading. Left unchecked, the Silty Pond Mussel could disrupt one of the most biodiverse freshwater regions in the country and cause significant ecological harm. Swift action to address this invasive species is essential to protecting the Wickecheoke Creek Preserve, safeguarding native species, and preserving the health of the Delaware River watershed.

Each project partner plays an essential roles in the eradication process. Rutgers University is performing the environmental DNA (eDNA) monitoring and analyzing the results. Princeton Hydro is applying targeted treatments to the ponds where the mussels were initially detected, and, if eDNA or physical sampling reveals signs of the mussels in other water bodies, the team will extend these treatments accordingly. Using a highly specialized approach, Princeton Hydro’s licensed applicators have partnered with SePRO to apply Natrix, an EPA-registered pesticide developed specifically for managing invasive mollusk populations. The 2024 phase of the project has incorporated significant advancements in treatment design. The team’s strategy is both preventative and responsive. The project has garnered financial support from the U.S. Fish and Wildlife Service and the Delaware River Greenway Partnership through the Lower Delaware Wild and Scenic Program.

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In addition to treatment, Princeton Hydro is focused on rigorous documentation and educational outreach. “It’s important for us to record every aspect of this project, not only from a scientific perspective but also for public education,” said the Princeton Hydro Director of Marketing & Communications Dana Patterson Grear. “We want to ensure this species is contained here and prevented from spreading throughout New Jersey or, worse, across the United States.” As part of these efforts, Princeton Hydro aims to share detailed information on the Silty Pond Mussel’s characteristics and identification markers. “By educating communities and environmental stakeholders on what to look for, we hope to empower rapid responses in other areas, should the species appear elsewhere,” said Patterson Grear.

Dive Deeper: Watch the Video on Eradication Efforts

As part of the project's commitment to transparency and education, New Jersey DEP Fish & Wildlife created a detailed video to showcase the silty pond mussel eradication and identification efforts. This video delves deeper into the techniques and collaborative approaches being used to address the invasive species. We encourage you to watch the video to gain a comprehensive understanding of the challenges faced and the innovative strategies employed in this groundbreaking effort.

[embed]https://www.youtube.com/watch?v=qplXLi5tOPY[/embed]

To learn more about invasive species, obtain practical tips for identifying and managing invasives, and take actions to help protect our local ecosystems, click here to check out our recent blog.

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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] => 2025-03-10 11:59:49 [post_modified_gmt] => 2025-03-10 11:59:49 [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 ) [6] => WP_Post Object ( [ID] => 15865 [post_author] => 1 [post_date] => 2024-11-12 10:07:45 [post_date_gmt] => 2024-11-12 10:07:45 [post_content] =>

Lake Hopatcong, New Jersey's largest freshwater lake, spans 2,600 acres and stretches over six miles, forming part of the border between Sussex and Morris counties in the state’s northern Highlands region. Just 40 miles from Manhattan, its proximity to the city, combined with its scenic beauty, recreational appeal, and rich biodiversity, has long made it a desirable destination for visitors, residents, and businesses alike. The lake’s waters and surrounding habitats support diverse wildlife, including aquatic plants, animals, birds, and other terrestrial species.

Increased residential and commercial development, along with the impacts of climate change, have placed growing pressures on the lake’s ecosystem. Managing these pressures is vital to preserving water quality and protecting the biodiversity of both the lake and its watershed.

The Lake Hopatcong Foundation (LHF) and Lake Hopatcong Commission (LHC) are dedicated to protecting the lake and balancing development with environmental stewardship. Through thoughtful planning, long-term sustainability initiatives, and strategic partnerships, they have worked to safeguard the lake’s ecological, economic, and recreational value.

Princeton Hydro, a long-standing partner in this effort, has been involved in restoring the lake and managing its watershed for over 30 years. Our work has focused on reducing pollutant loads, managing stormwater runoff, addressing invasive aquatic plants and nuisance algal blooms, and enhancing habitat quality. Together with LHF, LHC, and funding partners, we have implemented a variety of projects designed to protect the lake and the communities that rely on it.

As a key partner, the New Jersey Highlands Council (Highlands Council) has provided essential funding for many of these critical projects, ensuring they come to fruition. These efforts reflect the Council’s commitment to safeguarding Lake Hopatcong’s future while upholding the Highlands Act’s mission to protect natural resources and foster sustainable community growth. These collaborations are vital to the initiatives that preserve the lake’s water quality, restore habitats, and promote the long-term health of the region.

Showcasing Success at the New Jersey Highlands Council 20th Anniversary Event

In celebration of its 20th anniversary, the Highlands Council hosted a special event, which featured a “Lake Hopatcong Exhibit,” highlighting many of the successful projects that it funded. Representatives from LHC, LHF, Highlands Council, and Princeton Hydro, were on hand to discuss the significance of these projects and their contributions to the long-term health of the lake and surrounding communities.

The exhibit included a variety of interactive experiences, including informative posters and maps detailing project efforts. Participants were able to examine Lake Hopatcong water samples under microscopes with guidance from Dr. Fred S. Lubnow, Princeton Hydro Senior Technical Director of Ecological Services.

By highlighting both the challenges faced and the progress made, the exhibit offered attendees a deeper understanding of the lake’s critical role in the region’s environmental and economic sustainability as well as the ongoing efforts to maintain the lake's water quality and protect its ecological health.

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Lake Hopatcong Success Stories Funded by the New Jersey Highlands Council

Through funding from the Council, a variety of partners including LHF, LHC, Princeton Hydro, and local government agencies have been able to implement a myriad of projects. From stormwater management systems to watershed restoration efforts, these initiatives are designed to address issues like nutrient pollution, invasive species, and habitat degradation. These projects are helping to protect the lake’s water quality and ensure its healthy future:

Upper Musconetcong Watershed Implementation Plan (WIP): $109,000 to LHC

In 2021, the Upper Musconetcong River Watershed Restoration Plan was updated to a 9-element WIP. This revision re-evaluated existing conditions, integrated green infrastructure, and incorporated emerging technologies. The WIP has since facilitated funding for projects such as biochar installation, alum treatments to reduce phosphorus, and stormwater management improvements. 25% of the WIP ($27,250) was used as match toward a National Fish and Wildlife Foundation (NFWF) grant ($485,650). This effort led to NJDEP 319 (h) Stormwater Grant for Biofiltration at Lakeside Fields ($239,000).

Restoration Plan for Memorial Beach and Park in the Borough of Mount Arlington: $60,000 to Borough of Mount Arlington

A restoration plan was developed for the watershed that directly flows to Memorial Beach through the park. A series of stormwater management measures were recommended and subsequent funding was secured. This effort led to community-funded project for the dredging of Memorial Pond ($277,000) and a slope stabilization with native plantings at Memorial Pond via a NJ Department of Environmental Protection 319(h) grant. $70,500 was also used as match for NFWF Glen Brook Project (Total Project - Glen, Muscy, Witten - $485,650)

Preliminary Feasibility Assessment & Data Collection for Beneficial Reuse of Sediment in Landing Channel: $47,650 to Roxbury Township

Erosion of Floating Island, which located in Lake Hopatcong’s Landing Channel, contributed to significant sediment accumulation. A preliminary feasibility study conducted by Princeton Hydro explored dredging and habitat restoration options. The proposed beneficial reuse/dredging project would rehabilitate the island and lead to reduced phosphorus in the lake, increased beneficial wetland habitat, and improved water quality. The next phase of the project includes engineering design, permitting, and implementation.

Feasibility Study Update for Sewering Jefferson Township Section of Lake Hopatcong Watershed: $100,000 to Jefferson Township

A 25+ year-old feasibility study was updated to lay the groundwork for the the installation of sanitary sewers along the lakefront area of Jefferson Township, which is currently using septic systems. This marked the first step in addressing one of largest sources of phosphorus entering Lake Hopatcong and a pivotal milestone in the ongoing efforts to safeguard water quality and mitigate the risk of harmful algal blooms (HABs) on Lake Hopatcong. These efforts led to a Community Funded Project from Congresswoman Sherill’s Office ($750,000).

Design of a Bank Stabilization and Planting Project along the Musconetcong River: $89,500 to Roxbury Township

A bank stabilization design and planting plan was completed for a popular fishing location along the Musconetcong River between Lakes Hopatcong and Musconetcong. The project, led by the LHC with technical assistance from Princeton Hydro, aims to reduce sediment and nutrient levels in Lake Musconetcong by improving the condition of a key section of the Musconetcong River. The Highlands Council grant to Roxbury Township provided the critical first step in this long-term, multifaceted project.

Oxygenation Feasibility Study: $80,300 to Morris County

Princeton Hydro completed a feasibility study for the design of an oxygenation system for Lake Hopatcong. It aimed to address the lake’s internal phosphorus load that contributes toward the nuisance HABs over the summer months. Since the widespread occurrence of HABs in 2019, the LHF and the LHC have been actively exploring solutions to reduce their frequency. Oxygenation systems help prevent stagnation of water, increasing circulation, disrupting thermal stratification which provides “through-column” mixing, and minimizes the occurrence of HABs. The results of this study will be used to move the project forward into the permitting and implementation phases.

Design of a Regenerative Stormwater Conveyance System for Witten Park: $54,000 to Borough of Hopatcong

A planting plan and regenerative stormwater conveyance system design was completed to aid in the mitigation of stormwater in Witten Park. A new system will help to manage and treat stormwater within the park, reducing erosion and sediment that flows into Lake Hopatcong. The system will also restore the floodplain, wetlands, and streams, and improve the ecological health of the area. The funding from the Council was also used by LHC as in-kind match for a NFWF grant award ($353,000) for the permitting & implementation phases.

Three Year Trout Habitat Study at Lake Hopatcong: $130,000 to Jefferson Township

One of the most significant recreational draws to Lake Hopatcong is its trout fishery, recognized regionally by anglers and established as an important component of the local economy. Data collected over the past 30 years at the lake was analyzed and showed increasing surface water temperatures, a trend that may suggest that the trout carryover habitat is being negatively impacted. The LHC, in cooperation with the LHF and the Knee-Deep Club, initiated a three-year trout tagging study. The study focused on the introduction of larger trout to assess the long-term population dynamics of those stocked fish and the general health of the fishery.

Revitalization of Two Stormwater Basins in Roxbury Township: $98,100 to Roxbury Township

Planning documents, a hydraulic & hydrologic analysis, and an engineering report were prepared for the construction of two stormwater basin retrofits. The stormwater basin retrofit project aims to minimize runoff and reduce pollutants flowing into Lake Hopatcong, thus protecting water quality. The reconstruction of the basins is critical in managing stormwater effectively, preventing erosion, and reducing nutrient loads that contribute to harmful algal blooms. By improving these basins, the project plays a key role in safeguarding the lake's ecosystem and ensuring the long-term health of its water resources.

Development of Plans for Catch Basins at Shore Hills Beach Club: $42,500 to Morris County

A field assessment, survey, and engineering design was completed for the installation of stormwater treatment devices at each of the outfall systems at the Shore Hills Beach Club property, which is located at the southern most tip of Lake Hopatcong. The primary goal of the project is to reduce phosphorus loads entering the lake, which can lead to nuisance weed growth, reduced water quality, and the proliferation of HABs. This funding from the Council enabled the project's next phase: construction.

As we celebrate the 20th anniversary of the New Jersey Highlands Council and its vital contributions to Lake Hopatcong, it’s clear that the future of this treasured resource relies on ongoing collaboration among stakeholders, local communities, and environmental organizations. By implementing innovative solutions and promoting sustainable practices, we can ensure that Lake Hopatcong continues to thrive as both an ecological haven and a recreational hub. This collective effort not only enhances the lake’s water quality and biodiversity but also strengthens the economic vitality of the surrounding communities, fostering a legacy of environmental stewardship for generations to come.

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The South Cape May Meadows Preserve, owned and managed by The Nature Conservancy (TNC), is a jewel among New Jersey's protected landscapes. Spanning over 200 acres adjacent to Cape May State Park, the preserve is celebrated for its diverse habitats, including beaches, dunes, freshwater wetlands, and fields. As a crucial stopover along the Atlantic Flyway, it offers refuge to rare and endangered shorebirds as well as native and migratory birds, making it a globally renowned paradise for birders. It also supports a wide variety of terrestrial species year-round.

The Preserve also has a variety of features aimed at enhancing visitor experience, promoting sustainability, and supporting its diverse wildlife. These features include a welcome shed with a green roof, a rain garden, purple martin houses, a raised wildlife viewing platform, an osprey platform with a streaming camera, benches, interpretive signs, and an 80-foot bird blind.

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With its rich biodiversity, scenic beauty and unique features, the South Cape May Meadows Preserve is a site of high public interest and use, attracting approximately 90,000 visitors each year. To accommodate the high level of public interest and improve accessibility, TNC contracted Princeton Hydro to upgrade the existing path network to make it more physically accessible and to create new pathways that open up previously unreachable areas of the Preserve.

Given that much of the site is composed of freshwater wetlands, creating accessible pathways without disturbing these sensitive areas presented a unique challenge that required innovative solutions. To address this, the centerpiece of the project was the construction of an elevated boardwalk trail in the western area of the preserve. Slated for completion in September 2024, the new boardwalk will add 2,675 linear feet of elevated walking paths throughout the preserve, along with a 480-square-foot elevated viewing platform. The boardwalk will wind through previously inaccessible wetland areas and is designed to comply with ADA standards, ensuring that visitors of all abilities can explore and enjoy the preserve's unique maritime landscape.

Led by TNC, the Princeton Hydro team was responsible for designing, permitting, and overseeing construction for the project, with Renova serving as the primary construction partner. The images below are renderings and a mapped layout of the project site created by Landscape Architect Cory Speroff, PLA, ASLA, CBLP of Princeton Hydro, the lead project designer and project manager:

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Sustainable Construction Practices & Accessibility Enhancements

To minimize environmental impact during construction, the boardwalk is being installed using a top-down construction method. This approach required finding a product that could meet all design requirements while supporting the necessary equipment for construction from above. The project team selected GreenWalk™, a proprietary structure system manufactured by IDEAL Foundation Systems. GreenWalk™ is a highly engineered, modular, zero-maintenance boardwalk system that meets all of the project criteria while ensuring minimal disturbance to the wetland.

This video provides a behind-the-scenes look at the boardwalk installation process and the intricate work involved in bringing this accessible pathway to life. Watch now to see how we're making nature more accessible for everyone:

https://youtu.be/wSJeYM8ajPE

In addition to the boardwalk, the Princeton Hydro team designed and permitted several site improvements to enhance accessibility and visitor experience:

Existing trail surface types were assessed for sturdiness, and cost-effective measures were implemented to enhance accessibility. This included leveling the existing gravel and sandy portions of the Main and East trails and replacing them with a firmer, more stable surface.

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Equipped with safety railing, handrails, seated observation areas, and educational signs in both braille and English print, the boardwalk is designed to provide support for people with accessibility considerations.

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The existing parking lot was upgraded to include formal ADA spaces. One-third of the original stone parking lot was converted to concrete to improve accessibility.

These efforts ensure that the South Cape May Meadows Preserve remains an inclusive and ecologically sensitive destination, allowing all visitors to fully appreciate the natural beauty and biodiversity of this unique maritime landscape.

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Speroff emphasized that the boardwalk is more than just a pathway through nature; it symbolizes a collective commitment to protecting and celebrating the environment: “It stands as a reminder that we can create spaces that are both beautiful and functional, without compromising the health of our planet. By choosing sustainable materials and practices, we have set a standard for future projects in our community and beyond. Moreover, this boardwalk represents our pledge to inclusivity, going above and beyond the minimum standards for ADA compliance. We created a space where everyone, regardless of physical abilities, can enjoy the beauty of our natural surroundings—a place where families can come together, individuals can find solitude, and nature can be experienced by all.”

Celebrating a New Chapter in Visitor Experience

On Sunday, August 4, TNC hosted a ribbon-cutting ceremony at the South Cape May Meadows Preserve to unveil the new boardwalk trail and site enhancements. The event highlighted the significant strides made in increasing the preserve’s accessibility and offered attendees a preview of the new features, including four metal plaques with tactile elements and braille, showcasing nature themes like the life cycle of a butterfly and frog, turtle shells, and dragonflies.

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Speeches were given by Barbara Brummer, State Director of The Nature Conservancy in New Jersey; Paulo Rodriguez Heyman, President of Renova; Mark Gallagher, Vice President of Princeton Hydro; and both the father and grandmother of Julian Tao Knipper. The Knipper family generously donated to the project in memory of Julian, who dearly loved Cape May and tragically passed away at the age of three. The project also honored Pat and Clay Sutton, esteemed educators, authors, naturalists, photographers, lecturers, nature tour leaders, and long-time champions for the protection of Cape May’s rich biodiversity. The new trail was officially dedicated to Julian, Pat and Clay.

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Speroff expressed deep appreciation for the donors, stating, “The belief in this project and the willingness to invest in this vision made it possible to create a space that is accessible to all and harmonious with our natural surroundings. These contributions are not just financial; they are investments in the future of the Cape May community and our planet.”

It is essential to also acknowledge the invaluable contributions of those who made this project possible, creating a space where people of all abilities can enjoy nature, reflect, and find peace. Special thanks go to The Nature Conservancy, particularly Barbara Brummer, Eric Olsen, Damon Noe, Elliot Nagele, and the TNC project staff. The Renova Team's hard work and dedication were instrumental in bringing the one-of-a-kind boardwalk to life. Additionally, the design team, including IDEAL Foundation Systems, Bedford, L2A, and JBCI, played a crucial role in the project’s success. And, members of the Princeton Hydro team, especially Cory Speroff, PLA, ASLA, CBLP; Geoffrey M. Goll, P.E.; Ryan Eno, EIT; Ivy Babson; and Casey Pantaleo, P.E.

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A Legacy of Collaboration

The Nature Conservancy and Princeton Hydro have a storied history of working on impactful projects together, from removing obsolete dams and opening up miles of river for fish passage to eradicating invasive species right here on this property. A few years ago, we designed the removal of Columbia Lake Dam, which reconnected 20 miles of stream, with American Shad returning to their native spawning grounds upstream just months after it was removed. And now, as this South Cape May Meadows Preserve project nears completion, we celebrate a project that offers everyone the chance to experience its natural beauty and biodiversity. This collaboration between Princeton Hydro and TNC underscores the importance of creating inclusive spaces that honor and protect our natural world.

Within the next few weeks, stay tuned for more updates and photos as we near completion on this exciting project, ensuring that the South Cape May Meadows Preserve remains a cherished destination for all who visit.

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Mercer County Park, spanning over 2,500 acres across the Townships of West Windsor, Hamilton, and Lawrence, is a treasured natural resource. Like many waterbodies throughout New Jersey, some of the lakes within Mercer County Park have been increasingly affected by harmful algal blooms (HABs) in recent years. In response to the growing frequency, duration, and severity of these blooms, the Mercer County Park Commission (MCPC) has intensified its efforts to enhance the overall health of its lakes.

To address these challenges, the County of Mercer tasked the MCPC with developing a comprehensive Lake and Watershed Management Plan. The ultimate goal is to ensure the health, stability, and sustainability of the park's aquatic ecosystems, thereby enhancing the recreational experience for park users. In this endeavor, the MCPC has partnered with Princeton Hydro to bridge gaps in the existing data and create a thorough management plan.

The plan documents the current conditions of waterbodies within the park, including Mercer Lake, which is the largest, and its surrounding watershed; identifies and prioritizes existing and potential water quality challenges; and provides targeted recommendations for treatment and restoration.

Princeton Hydro conducted a detailed analysis of the lakes' ecological health, including water quality monitoring, bathymetric mapping, and assessment of hydrologic and pollutant budgets. These comprehensive efforts have culminated in a robust management plan designed to protect and improve the lakes' ecological balance and recreational value.

Expanding the Initiative Across Mercer County

While Mercer Lake is a key focus, Princeton Hydro's commitment extends beyond this single waterbody. Recognizing the interconnected nature of the county's aquatic ecosystems, the team conducted similar analysis and developed Lake and Watershed Management Plans for three additional lakes in other parks within Mercer County.

These lakes are:

Curlis Lake in Curlis Lake Woods Park
Rosedale Lake in Rosedale Park
Spring Lake in John A. Roebling Memorial Park

Each of these lakes, like Mercer Lake, faces unique challenges related to maintaining water quality, protecting ecological balance, and mitigating HABs. By applying a comprehensive approach tailored to the specific conditions and needs of each lake, Princeton Hydro aims to enhance the overall health of these vital resources.

Let's dive into the details of Mercer Lake's plan!

Historical Data Review: Laying the Foundation for Informed Management

The first crucial step in developing Mercer County Park's comprehensive lake management plan involved a thorough review of historical data obtained from various sources, including the County, New Jersey Department of Environmental Protection (NJDEP), New Jersey Department of Transportation (NJDOT), and U.S. Geological Survey (USGS). This review was essential for capitalizing on established water quality trends, identifying recurring problems, and evaluating the success of previous restoration efforts.

The historical data review spanned an impressive range of years from 1963 to 2016, though it did contain some significant gaps. Despite these gaps, the long-term data provided invaluable insights into the lake's ecological history. By integrating reliable data from past studies, the team could complement their field efforts with supplemental information.

Princeton Hydro examined data on Mercer Lake, a key focus of the management plan initiative, and on all streams within each watershed that feed into the lake. This included any available surface water data from the USGS, a standard approach in aquatic system studies. By analyzing these data, the team identified trends in water quality, highlighted persistent issues, and assessed the effectiveness of past restoration efforts.

This comprehensive historical data review set the stage for a robust watershed assessment, ensuring that the management plan would be informed by a solid foundation of past knowledge.

Bathymetric Survey: Mapping Mercer Lake's Depths and Sediments

A bathymetric survey is a scientific method used to map the depths and topography of waterbodies, providing detailed information about the underwater terrain and the distribution of sediments. This survey is crucial for understanding various aspects of a lake's ecosystem, including sediment thickness, water volume, and potential areas for dredging. The data gathered from a bathymetric survey helps in making informed decisions regarding the restoration and protection of lakes.

Princeton Hydro conducted the bathymetric survey using a calibrated sounding rod for shallow areas and a dual-frequency echo sounder with GPS for deeper regions. The sounding rod was employed in areas with water depths of 12 inches or less and where sediment composition hindered echo sounding. The echo sounder, a Knudsen Engineering model 1612, used high and low frequencies to distinguish the top and bottom of sediment layers. Data points were collected along predetermined transects spaced 150 feet apart, running from shoreline to shoreline in a north-south direction.

Once fieldwork was completed, the collected data was processed using Hypack Max software. This involved editing the raw sounder data to correct errors such as double reflections and interference from aquatic vegetation. The cleaned data was exported to ArcGIS for further analysis and mapping.

The results of the bathymetric survey revealed that Mercer Lake, a key focus of the lake management plan, covers a surface area of approximately 287 acres and is primarily an oval-shaped impoundment. The lake receives inflow from Assunpink Creek and its tributaries and discharges water westward, eventually reaching the Delaware River, Delaware Bay, and the Atlantic Ocean.

Mercer Lake was found to be relatively shallow, with a mean depth of 8.9 feet and a maximum depth of 18.5 feet. The total volume of water in the lake was estimated at around 2,560 acre-feet, or 834.2 million gallons. The survey also indicated significant sediment deposition in the eastern portion of the lake, with a total sediment volume of approximately 855,325 cubic yards. This pattern is likely due to the lake's role as a settling area for sediment carried by tributary inflows and stormwater discharges, which transport debris, leaf litter, and other materials into the lake.

Below is an image of the Bathymetric Survey that provides a detailed view of the sediment thickness contours measured in feet throughout Mercer Lake:

By establishing a detailed understanding of Mercer Lake's depth and sediment distribution, the bathymetric survey provides a robust foundation for the comprehensive lake management plan, informing long-term management decisions. The bathymetric data collected is also essential for evaluating the need for dredging, understanding aquatic plant colonization patterns, and predicting the lake's response to incoming nutrients, helping to guide restoration and protection efforts.

Hydrologic and Pollutant Loading Analysis: Understanding the Sources and Impacts of Pollution

Hydrologic and Pollutant Loading Analysis is crucial for identifying the sources and impacts of pollutants entering a waterbody. It involves delineating watersheds, assessing hydrologic data, and evaluating nutrient loads.

For Mercer Lake, Princeton Hydro conducted an extensive analysis using tools such as USGS StreamStats and Stroud Research Center’s Model My Watershed®. This study provided a detailed understanding of the water and pollutant dynamics within the Mercer Lake watershed. The map below offers an aerial view of the watershed, illustrating the various types of land cover present within the area:

Runoff varied considerably between different sub-watersheds due to factors like land cover types, land-use consumption, impervious surfaces, and topography. Variations in elevation change also determine the impact runoff has on soil erosion, with steeper slopes causing higher erosion rates, especially if little vegetation is present. The chart below shows the various types of soil coverage in areas throughout the Mercer Lake watershed:

Princeton Hydro also assessed other pollutant sources, including groundwater seepage, streambank erosion, and contributions from residential septic systems. Additionally, the impact of waterfowl, particularly Canada Goose, was evaluated using nutrient loading coefficients. The presence of these birds significantly contributes to phosphorus and nitrogen levels.

The hydrologic budget, representing the water balance of the lake, was calculated by considering inputs such as direct precipitation, overland runoff, tributary inflow, and groundwater seepage. This data is vital for conducting trophic state analyses and determining the feasibility of various in-lake restoration techniques. Internal loading of phosphorus, which occurs when anoxic conditions in the lake's bottom sediments release bound phosphorus into the water, was also analyzed.

Results of the analysis revealed that Mercer Lake, covering 287.1 acres, is influenced by a watershed area of 20,551.4 acres, predominantly consisting of cropland and forested areas. The lake's shallow nature coupled with significant sediment deposition in the eastern portion, underscores the importance of managing both external and internal nutrient loads.

Understanding the hydrologic and pollutant dynamics through this detailed analysis allows for the development of a lake management plan that helps to prioritize management efforts, target the primary sources of pollution, and effectively address HABs.

Water Quality Monitoring: Ensuring a Healthy Ecosystem

Monitoring water quality is essential for understanding the existing chemistry of a lake, identifying trends, pinpointing problems, and assessing nutrient levels. It provides critical data that informs management decisions and helps maintain the health and stability of aquatic ecosystems.

For Mercer Lake, Princeton Hydro conducted thorough water quality monitoring from 2021 to 2023. This involved analyzing in-situ, discrete, and plankton data collected over three growing seasons. The monitoring focused on various parameters, including hypolimnetic anoxia and associated phosphorus dynamics, which are key contributors to HABs. The data collected offered a current assessment of the lake’s trophic state and plankton community, providing a baseline to document shifts in water quality in response to future management measures.

The Princeton Hydro team performed 13 sampling events at two consistent stations in Mercer Lake: a deep water station near the dam (ML-1) and a mid-lake station (ML-2). Various parameters were monitored, including water temperature, dissolved oxygen (DO), pH, specific conductivity, chlorophyll a, and phycocyanin, using an In-Situ AquaTROLL 500 meter.

Water samples were collected at both in-lake stations at the surface (0.5 meters) and near the bottom (0.5 meters above the sediment) using a Van Dorn water sampler. Samples were preserved appropriately and transported to the NJDEP-certified laboratory Environmental Compliance Monitoring (ECM) for analysis. The samples were analyzed for total phosphorus (TP), soluble reactive phosphorus (SRP), total dissolved phosphorus (TDP), nitrate-N, nitrite-N, ammonia-N, total suspended solids (TSS), and turbidity. Surface samples were also analyzed for alkalinity, chloride, and hardness.

Additionally, samples were collected for zooplankton and phytoplankton analysis, including species composition, dominant organisms, and relative density. Cyanobacteria (blue-green algae) genera were quantified to estimate cell counts, providing an approximate concentration of cyanobacteria cells per milliliter of water. Samples were also analyzed for the cyanotoxin microcystins using the Abraxis field testing methodology.

The team also evaluated local climatic conditions during the 2021 - 2023 seasons compared to the long-term average. These conditions, including temperature and precipitation, can have significant effects on water quality. The combination of increased precipitation and an increase in temperatures sets the stage for HABs proliferation. The charts below the monthly mean temperatures and monthly precipitation from 2021 – 2023 and the 30-year average; ‘normal’ refers to the monthly average over the 30-year period from 1991 – 2020.

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The Water Quality Monitoring analysis revealed several key insights about Mercer Lake's water quality, and indicated that cropland runoff was the most significant source of phosphorus, a key driver of HABs. Hypolimnetic anoxia (the bottom layer of the lake becomes devoid of oxygen) was observed during all three field sampling seasons, contributing to internal phosphorus loading. The water quality monitoring also provided valuable information on the lake’s trophic state and plankton community.

Trophic State Modeling: Assessing Lake Productivity

Trophic State Modeling is a method used to assess the productivity of a lake by measuring the levels of nutrients, such as phosphorus, and the resulting biological activity. This assessment helps determine the lake's overall health and informs management strategies. The Trophic State Index (TSI) is a common tool used in this process, calculating index values based on phosphorus concentrations, chlorophyll a levels, and Secchi depths.

For MCPC, Princeton Hydro, utilizing data collected in the field and through lake and watershed modeling, estimated the nutrient status and biological activity of Mercer Lake. Here are a few examples of the models the team utilized:

The Carlson’s Trophic State Index (TSI): This index assesses the trophic state of lakes by calculating index values based on phosphorus and chlorophyll a concentrations and Secchi depths that relate to each other on a similar scale. The higher these numbers are, the more representative they are of eutrophic conditions. Carlson’s trophic state index (TSI) was calculated for each in-lake sampling event using surface concentrations of TP, Chlorophyll a, and Secchi depths collected during water quality monitoring events throughout the season.
Kirchner and Dillon’s Phosphorus Retention: This metric utilizes the incoming hydraulic load from the watershed, as well as the total area of the waterbody, to estimate what percentage of incoming phosphorus will stay within the waterbody rather than be flushed from the system, providing insights into the lake's capacity to hold nutrients and its likelihood of eutrophic conditions.
Vollenweider Predicted Phosphorus: this model estimates phosphorus concentrations in a lake by considering incoming total phosphorus, hydraulic load, mean depth, and hydraulic residence time. This model helps assess the lake's nutrient status and its suitability for recreational use.

By leveraging these sophisticated models, Princeton Hydro was able to gain a detailed understanding of Mercer Lake's nutrient dynamics and productivity. Many models were run twice: once for the watershed-based phosphorus load and once for the total combined load. This allowed for a comprehensive assessment of both external and internal nutrient contributions.

To mitigate pollutant loading issues, the Lake and Watershed Management plan outlines a series of Best Management Practices (BMPs) recommendations for implementation throughout the watershed, which include bioretention systems, wetland buffers, riparian buffers, and lakefront aquascaping. Such measures are designed to reduce nutrient loads, improve water quality, and enhance the overall ecological health of the lake and its watershed. By addressing the root causes of nutrient loading and implementing targeted management strategies, the MCPC is continuing their commitment to providing a sustainable and enjoyable recreational experience for park users while safeguarding the lake's ecological integrity.

Stay tuned for more updates as we continue to work with the MCPC on implementing the Mercer Lake and Watershed Management Plan, ensuring the watershed remains a vibrant and healthy resource for generations to come.

The Importance of Regional Watershed Planning

Regional watershed planning is crucial for maintaining the health and sustainability of interconnected waterbodies. By considering entire watersheds rather than individual lakes, we can develop more effective and comprehensive strategies to manage water quality, control pollution, and enhance ecological resilience. This holistic approach ensures that all elements within the watershed are addressed, leading to more long-lasting improvements.

Princeton Hydro’s efforts in developing and implementing management plans for Mercer Lake, Curlis Lake, Rosedale Lake, and Spring Lake demonstrate the power of coordinated, science-based planning. By leveraging detailed data and advanced modeling techniques, our team is able to create tailored solutions that meet the specific needs of each lake while contributing to the overall health of the region's aquatic ecosystems.

To read about another project we’re working on in Mercer County, check out our blog about Miry Run Dam Site 21. Through a blend of engineering and ecological enhancements, we are working with MCPC to revitalize 279 acres. With each phase, we edge closer to a vibrant, inclusive space that harmonizes nature and community.

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After 129 years, the Paulina Lake Dam in Warren County is in the final stages of demolition. This project, led by The Nature Conservancy's New Jersey Chapter, is hailed by local advocates as a significant environmental victory. The complete removal of the dam, scheduled from July through September 2024, is the second of three phases of river restoration, and signifies a major milestone in the rehabilitation of the Paulins Kill River, New Jersey’s third-largest tributary to the Delaware River.

On November 24, 2023, a crucial step in the restoration journey was taken with the first notching of the Paulina Dam. This initial step set the stage for the next phase of the dam removal, which is now in full swing. The project, a successful collaboration under the leadership of The Nature Conservancy, funded by NJDEP Division of Fish and Wildlife, and designed and implemented by Princeton Hydro and RiverLogic-Renova Joint Venture, respectively, is progressing toward its goal. The third and final phase will occur in 2025 for adaptive management to complete the finishing touches, including the installation of habitat features to further enhance the biodiversity of this river segment.

Watch the Progress Unfold

Click below to watch a new video showcasing the project's progress. The drone footage captures the project team in action, demolishing the dam, removing sediment upriver, and strategically placing rock check dam to control the flow of sediment as the removal process continues.

[embed]https://youtu.be/5VDkbvBr1z4[/embed]

Laying the Foundation for Change

Blairstown’s original power source for electricity, the Paulina Lake Dam, located in bucolic Warren County, NJ, has long posed challenges to the river’s health and surrounding communities. Originally constructed to produce hydropower, it has not functioned in that capacity for over 50 years. Its removal is crucial not only for mitigating risks to life and property but also for restoring the natural habitat for native species like brook trout and migratory fish.

Located in bucolic Warren County, New Jersey, The Paulina Lake Dam, Blairstown’s original power source for electricity, has long posed challenges to the river’s health and, after the dam ceased its use as a power source, became a financial and safety liability to Blairstown Township. Its removal is crucial not only for mitigating risks to life and property but also for restoring the natural habitat for native species like brook trout and migratory fish.

This initiative aims to:

Reconnect an additional 7.6 miles of river habitat along the Paulins Kill River, adding to the 10 miles that were restored after the removal of the Columbia Lake Dam, a project led by The Nature Conservancy and designed by Princeton Hydro.
Improve aquatic and terrestrial connectivity, enhancing the ecosystem for fish, mussels, and other wildlife.
Enhance water quality and public safety, reducing the risk of an unplanned breach.
Boost recreation opportunities, providing a safer and more enjoyable environment for the community.

A Comprehensive Effort for Environmental Restoration

The removal of the Paulina Lake Dam is part of a larger restoration plan initiated in 2013 by The Nature Conservancy, which includes the removal of multiple dams along the Paulins Kill River, planting thousands of trees in its riparian zone, and restoration of its headwater Hyper Humus, a glacially created peat bog. This comprehensive effort, involving wetland restoration, land protection, and floodplain reforestation, aims to rejuvenate and sustain the river ecosystem.

Princeton Hydro’s President, Geoffrey M. Goll, PE, highlights the broader impact of these efforts: “The removal of Paulina Lake Dam is not just about dismantling a structure and removing a safety hazard, but paving the way for a renewed riverine landscape, where the flow of life returns to its natural course.”

As we celebrate this major milestone, we look forward to witnessing the continued transformation of the Paulins Kill. This project stands as a testament to the power of collaboration, environmental stewardship, and the unwavering dedication of communities and organizations committed to preserving and restoring our natural landscapes.

Stay tuned for more updates as we continue this exciting journey towards a restored and thriving river ecosystem this fall, and then the finishing touches in 2025! Click here to learn more about the Paulina Lake Dam removal and the broader restoration efforts.

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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.

Identifying and Addressing Harmful Algal Blooms

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.

Laying the Groundwork

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.

Understanding Cyanobacteria Behavior Through Innovative Research

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:

This map identifies the locations of each of the six sampling sites at Smith Mountain Lake

[gallery link="none" columns="2" ids="15361,15363"]

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:

1. Sediment Composition and Cyanobacteria Growth: Sandier sediments were not conducive to overwintering cyanobacteria, suggesting blooms in these areas likely originate elsewhere in the lake. Conversely, siltier and organic-rich sediments supported cyanobacteria growth, indicating a need for targeted in-lake management measures. 2. Predictive Tools for HABs: Routine measurement of pigments like PC and PE proved effective in estimating cyanobacteria biomass. This information is crucial for long-term monitoring and management, offering predictive tools for HAB events.

Looking Ahead: Holistic Approaches to Tackling HABs

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.”

[gallery size="medium" link="none" ids="15377,15374,15373"]

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.

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Watch the Latest Project Video

Click below to watch it now: [embed]https://www.youtube.com/watch?v=VDbe6oUPEOI[/embed]

A Legacy of Connectivity and Restoration

What’s Next?!

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Posted on March 14, 2025 by Princeton Hydro

Watch the Latest Project Video

A Legacy of Connectivity and Restoration

What’s Next?!

Restoring Vital Habitat in a Developed Landscape

A Haven for Wildlife

Continuing the Commitment to Wildlife Conservation

Galaxes Weir Removal: A Groundbreaking First for Portugal

Perofilho Weir Removal: Establishing a Blueprint for River Restoration

Oeiras River Restoration: A Comprehensive Plan for Connectivity

Collaborating for a Sustainable Future

Acknowledgments: Celebrating the Power of Partnerships

Diving Into Data

Delineating a Watershed

Collaborating Across Teams

Fieldwork and Fresh Air

Overcoming Challenges with Innovation and Care

Continued Inspiration

Protecting Biodiversity and Partnering for Eradication

Dive Deeper: Watch the Video on Eradication Efforts

Showcasing Success at the New Jersey Highlands Council 20th Anniversary Event

Lake Hopatcong Success Stories Funded by the New Jersey Highlands Council

Upper Musconetcong Watershed Implementation Plan (WIP): $109,000 to LHC

Restoration Plan for Memorial Beach and Park in the Borough of Mount Arlington: $60,000 to Borough of Mount Arlington

Preliminary Feasibility Assessment & Data Collection for Beneficial Reuse of Sediment in Landing Channel: $47,650 to Roxbury Township

Feasibility Study Update for Sewering Jefferson Township Section of Lake Hopatcong Watershed: $100,000 to Jefferson Township

Design of a Bank Stabilization and Planting Project along the Musconetcong River: $89,500 to Roxbury Township

Oxygenation Feasibility Study: $80,300 to Morris County

Design of a Regenerative Stormwater Conveyance System for Witten Park: $54,000 to Borough of Hopatcong

Three Year Trout Habitat Study at Lake Hopatcong: $130,000 to Jefferson Township

Revitalization of Two Stormwater Basins in Roxbury Township: $98,100 to Roxbury Township

Development of Plans for Catch Basins at Shore Hills Beach Club: $42,500 to Morris County

Sustainable Construction Practices & Accessibility Enhancements

Celebrating a New Chapter in Visitor Experience

A Legacy of Collaboration

Expanding the Initiative Across Mercer County

Historical Data Review: Laying the Foundation for Informed Management

Bathymetric Survey: Mapping Mercer Lake's Depths and Sediments

Hydrologic and Pollutant Loading Analysis: Understanding the Sources and Impacts of Pollution

Water Quality Monitoring: Ensuring a Healthy Ecosystem

Trophic State Modeling: Assessing Lake Productivity

The Importance of Regional Watershed Planning

Watch the Progress Unfold

Laying the Foundation for Change

A Comprehensive Effort for Environmental Restoration

Identifying and Addressing Harmful Algal Blooms

Laying the Groundwork

Understanding Cyanobacteria Behavior Through Innovative Research

Looking Ahead: Holistic Approaches to Tackling HABs

Watch the Latest Project Video

A Legacy of Connectivity and Restoration

What’s Next?!

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