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In urban areas, streams have often been buried beneath streets, buildings, and infrastructure, cutting them off from the natural ecosystem. However, a growing movement towards "daylighting" streams—uncovering and restoring these buried watercourses—has proven to be an innovative solution for improving water quality, reducing flood risks, restoring fish passage, and creating healthier habitats. Princeton Hydro has been at the forefront of these efforts, bringing expertise in ecological restoration and water resource management to daylighting projects across New Jersey.
Daylighting is the process of removing obstructions and impervious surfaces from a buried stream or river, restoring it to a more natural state. Often, streams were diverted underground to make way for urban development. Daylighting involves reversing this process, bringing the water flow back above ground where it can interact with the natural environment. The result is a newly visible, revitalized waterway that reconnects the stream to its surrounding ecosystem. This process not only improves stormwater management but also enhances urban spaces and promotes healthier habitats.
Daylighting streams offers numerous advantages to both the environment and local communities. Some key benefits include:
Princeton Hydro has successfully completed numerous daylighting projects that demonstrate the transformative power of restoring natural waterways. By leveraging innovative engineering and ecological practices, these projects restored the natural flow of waterways and enhanced the surrounding landscape. Let’s take a closer look at two examples:
In the heart of Trenton, NJ, Princeton Hydro undertook a comprehensive stream restoration. The City of Trenton, as part of a larger urban revitalization and brownfield redevelopment project, sought to restore the stream, Petty’s Run, which had long suffered from typical urban afflictions: pollution, flooding, and heavy debris accumulation.
Princeton Hydro developed a green infrastructure design that addressed these challenges holistically. The design included removing from the stream channel heavy debris, contaminated soils, and the concrete remains of previous development. The team also replaced the restrictive upstream road crossing with a pedestrian bridge, enhancing both the stream’s flow and the community’s connectivity. A significant aspect of the project involved daylighting the 250-foot underground portion of Petty’s Run, restoring it to a natural, open flow while creating an adjacent floodplain meadow to manage stormwater and provide habitat.
The project improved stormwater management, enhanced the landscape’s biodiversity, added habitat value, and established a new public green space with walking trails, which now serves as both an ecological asset and a recreational area for the community. This project earned both the Phoenix Award for Brownfield Redevelopment and the Bowman’s Hill Land Ethics Award.
Thompson Park, a sprawling 675-acre recreational area in Middlesex County, NJ, boasts a variety of amenities, including hiking trails, ballfields, and a zoo that is home to over 50 geese and fowl, goats, and approximately 90 deer. The streams within the park faced challenges, particularly in the areas surrounding the zoo’s enclosures, including erosion and compromised water quality.
In order to increase channel stability, decrease erosion, improve water quality and ecological function, and reduce the pollutants originating from the zoo, a stormwater management treatment train was designed and constructed.
Middlesex County Office of Parks and Recreation and Office of Planning, New Jersey Department of Environmental Protection, South Jersey Resource Conservation and Development Council, Middlesex County Mosquito Extermination Commission, Freehold Soil Conservation District, Rutgers Cooperative Extension, Enviroscapes and Princeton Hydro worked together to fund, design, permit, and construct numerous stormwater management measures within Thompson Park.
One of the key project initiatives involved daylighting a section of a 24-inch reinforced concrete pipe (RCP) that had previously conveyed stormwater underground. Daylighting the stream, widen the stream channel, improved stormwater absorption, reduced erosion, helped restore the stream’s natural gradient, and improved aquatic habitat.
This multi-faceted restoration project improved stream function and created a more sustainable environment for both zoo inhabitants, the park’s visitors, and the watershed.
Princeton Hydro’s President and Founding Principal, Geoffrey M. Goll, PE, recently shared his expertise in stream restoration during a "Daylighting Streams: Design & Engineering" webinar hosted by The Watershed Institute. The webinar explored the process of uncovering and restoring buried watercourses. Moderated by Susan Bristol, The Watershed Institute Municipal Policy Specialist, the webinar featured experts Vince Sortman, Biohabitats Senior Fluvial Geomorphologist; Warren T. Byrd, Jr., FASLA, Founding Partner of Nelson Byrd Woltz Landscape Architects & Professor Emeritus, University of Virginia; and Geoffrey. The webinar provided valuable insights into the challenges and benefits of these projects, highlighting the importance of hazard mitigation, maintenance, and community involvement in successful daylighting initiatives. The event underscored the significance of daylighting in enhancing both urban infrastructure and natural ecosystems.
Daylighting streams is a forward-thinking approach to urban water management that brings immense benefits to the environment and local communities. As daylighting continues to gain recognition as an essential tool for watershed restoration, Princeton Hydro remains a trusted leader in the field, combining innovative design with environmental stewardship.
For the first time in over 200 years, the lower Bushkill Creek is now free-flowing and fully reconnected with the Delaware River and, ultimately, the Atlantic Ocean. This tremendous achievement signals a turning point for the ecological health of the Bushkill Creek watershed, supporting the passage of migratory fish species, bolstering ecologically beneficial freshwater mussel populations, reconnecting river habitats that benefit fish and wildlife, and enhancing water quality across the Delaware River Basin, which provides drinking water to millions of people.
"This significant, yearslong restoration effort exemplifies the power of conservation partnerships to achieve profound ecological impact,” said Princeton Hydro President and Founding Principal Geoffrey M. Goll, PE “The restored Bushkill Creek is more than a reconnected waterway—it is a revitalized natural resource that enhances biodiversity, supports community recreation, and contributes to the local economy in sustainable ways.”
Bushkill Creek begins at the foot of Blue Mountain in Bushkill Township, Pennsylvania, and flows for 22 miles through agricultural and suburban areas, including Easton. The limestone stream supports a thriving wild brown trout population and is designated as a “high-quality, cold-water fishery” cherished by anglers and the local community.
Since 2021, Wildlands Conservancy has led the charge to remove five aging dams along Bushkill Creek. While these structures once served industrial and community functions, they had become barriers to fish migration, disrupted the creek’s natural flow, and contributed to localized flooding and water quality issues. Now, with these obstacles cleared, Bushkill Creek flows freely from its headwaters to its confluence with the Delaware River.
Along the creek, the removal of Dam #2 signifies a momentous occasion in its restoration journey, representing the most recent advancement in dam removal efforts.
Led by the Wildlands Conservancy, the restoration of Bushkill Creek involved more than 20 stakeholders, including the Delaware River Basin Commission, Lafayette College, Pennsylvania Department of Environmental Protection, National Fish and Wildlife Foundation, Pennsylvania Department of Conservation and Natural Resources, and Princeton Hydro.
In a press release from the Wildlands Conservancy, President Christopher Kocher, praised the collaborative effort, stating, “This yearslong effort is a win for clean water for all the communities living in connection with the Bushkill Creek. It’s a wonderful example of the power of partnerships, and what community can do for community when nonprofits, local government, and state and federal agencies pool ideas and resources to invest in our treasured natural areas.”
To celebrate this tremendous accomplishment, Wildlands Conservancy, project partners, funders, and community volunteers gathered on October 15, 2024, at Lafayette College’s Karl Stirner Arts Trail.
The event included a volunteer-powered wildflower planting to complete the restoration work at this site, where Dam #1, formerly owned by Lafayette College, had been removed in 2023 with the support of Princeton Hydro. Spanning 90 feet in length and standing 4 feet high, the dam had severely obstructed fish passage, contributed to local flooding, and impaired water quality over time. The college enthusiastically supported the dam's removal, dedicating substantial resources to see the project to completion.
Wildlands Conservancy, a non-profit land trust based in eastern Pennsylvania, is dedicated to the restoration of degraded stream and wildlife habitats, with a primary focus on the Lehigh Valley and the extensive Lehigh River watershed, which spans 1,345 square miles, eventually merging with the Delaware River. For over a decade, Princeton Hydro has been a steadfast partner to Wildlands Conservancy in their mission, collaborating on multiple dam removal projects in the Delaware River Watershed.
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.
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.
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:
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.
The removal of Bushkill Creek Dam #2 is now underway, marking yet another remarkable milestone in the rejuvenation of this treasured limestone stream. This achievement comes on the heels of four successfully completed dam removals since 2021, highlighting the swift progress in the revitalization efforts for Bushkill Creek.
This latest endeavor holds immense significance in facilitating the passage of migratory fish species, such as alewife and American shad, to vital upstream spawning grounds. It contributes to the recovery of ecologically-beneficial freshwater mussels and the bolstering of populations of trout and other resident fish species. And, it marks another important step in returning Bushkill Creek to its natural, free-flowing state.
During a recent site visit, Princeton Hydro President and Founding Principal Geoffrey M. Goll, P.E. took a moment to reflect on the years of hard work that have culminated in this significant milestone. Watch now:
In 2022, Wildlands Conservancy enlisted the expertise of Princeton Hydro to embark on a mission to remove four dams along Bushkill Creek. The successful removal of the Crayola Dam, also known as Dam #4, marked the beginning of this transformative journey. Subsequently, in 2023, Dams #1 and #3 were dismantled. Now, we celebrate the commencement of the removal of Dam #2.
Bushkill Creek flows 22-miles through agricultural and suburban landscape before converging with the Delaware River. Dam #2, situated upstream from the Creek’s confluence with the Delaware River, obstructed fish passage, exacerbated local flooding, and degraded water quality, much like its counterparts. Its removal represents a significant leap forward in the restoration of Bushkill Creek's ecological health.
The ongoing restoration of Bushkill Creek is a testament to the dedication of over 20 stakeholders, including, but not limited to, Wildlands Conservancy, the Delaware River Basin Commission, Lafayette College, Pennsylvania Department of Environmental Protection, National Fish and Wildlife Foundation, Pennsylvania Department of Conservation and Natural Resources, and Princeton Hydro.
Funding for the projects has stemmed from various sources, including a settlement following a fly ash spill from the Martins Creek Power Plant in 2005. This settlement, coupled with contributions from organizations like NFWF’s Delaware Watershed Conservation Fund and Northampton County’s Livable Landscapes program, propelled the initiative forward.
As we celebrate the start of removing Bushkill Creek Dam #2, we anticipate continued progress in the revitalization of this vital waterway. Each dam removed brings us closer to realizing the vision of a thriving, free-flowing Bushkill Creek, benefitting both the environment and local communities.
Wildlands Conservancy, a non-profit land trust based in eastern Pennsylvania, is dedicated to the restoration of degraded stream and wildlife habitats, with a primary focus on the Lehigh Valley and the extensive Lehigh River watershed. Spanning 1,345 square miles, this watershed eventually merges with the Delaware River.
For over a decade, Princeton Hydro has been a steadfast partner to Wildlands Conservancy in their mission, collaborating on multiple dam removal projects in the Lehigh River Valley. With expertise in design, permitting, and oversight, Princeton Hydro has played a pivotal role in the removal of over 80 small and large dams/barriers across the Northeast.
To explore Princeton Hydro's comprehensive fish passage and dam removal engineering services, click here. For more information about Wildlands Conservancy and their conservation efforts, click here.
The Watershed Institute and Princeton Hydro proudly present the inaugural Watershed Restoration Academy - Healthy Streams 101.
This two-day, entry level educational course is designed for water resources professionals (i.e., engineers, scientists, landscape architects, planners, restoration practitioners) seeking to obtain the foundational knowledge essential for advancing in the field of stream restoration.
Led by a licensed professional engineer, fluvial geomorphologist, regulatory experts, and watershed scientists, the course will delve into watershed analysis, stream processes, and site assessments through a balanced blend of classroom lectures and hands-on fieldwork.
Don't miss this opportunity to expand your knowledge and make a meaningful impact on stream restoration efforts. Register now to secure your spot.
Click here to read about the largest stream restoration project in Maryland. We worked with GV-Petro, a partnership between GreenVest and Petro Design Build Group, to restore over 7 miles (41,000 linear feet) of Tinkers Creek and its tributaries.
Within the intricate network of aquatic ecosystems, the American shad stands as a captivating enigma. This intrigue was recently explored in a webinar hosted by The Watershed Institute titled “The Mysterious World of the American Shad and Work to Bring Them Back to Our Waterways.” Led by The Watershed Institute’s Executive Director Jim Waltman and Princeton Hydro’s Senior Technical Director in Engineering and American shad expert Dr. Clay Emerson PE, CFM, the webinar explored the complex dynamics surrounding this iconic species, including its historical significance, unique migration patterns, and conservation efforts.
As the American shad embark on their annual upstream journey for spawning, the timing is especially poignant for a closer examination of this vital species and an exploration of strategies to safeguard and revive their populations. We invite you to enjoy our blog, which encapsulates the webinar's key insights, and to watch the full recorded session made available by The Watershed Institute.
American shad (Alosa sapidissima) are the largest members of the herring family. Their closest relatives are herring, sardines, and menhadens. They are an anadromous fish species, like salmon and steelhead (Oncorhynchus mykiss), that live most of their life in the ocean and migrate to freshwater rivers and streams to spawn. The American shad migration routes span vast distances, from the St. Johns River in Florida to the St. Lawrence River in Quebec, showcasing their tenacity and adaptability.
Not only do American shad undertake astonishingly long journeys to spawn, they also showcase distinctive migratory behaviors. Unlike many other anadromous species, these resilient shad can complete multiple round trips from freshwater to the ocean over their lifespan, challenging the conventional notion of 'one and done' spawning observed in Pacific salmon (Oncorhynchus) and sea lamprey (Petromyzon marinus).
Young shad will remain in the rivers where they hatched for several months. Migration out to the ocean typically occurs in late summer in the south, and early fall in the north, typically when the shad are 3-4 inches in size. Then, after 3-6 years of growth at sea, the shad migrate back to fresh water to spawn. Some shad make the journey to their spawning grounds 5-6 times over the course of their lifetime. Shad’s affinity for their birthplace adds a fascinating layer to their story. Approximately 95% of shad return to the rivers where they were hatched, with only 5% straying to unfamiliar waters to spawn.
American shad's unique hearing abilities are another noteworthy aspect. Endowed with specific biological features, shad exhibit exceptional sensitivity to water movements and noise, particularly attuned to sounds like clicks and echolocation. This acute sense plays a vital role in navigating their environment and evading predators such as dolphins.
Such intriguing characteristics make the American shad not only a vital component of aquatic ecosystems but also a subject of admiration and study among enthusiasts and conservationists alike.
Throughout history, American shad have held a vital place in the cultural heritage and economic prosperity of the United States, earning them the esteemed title of "America's Founding Fish.” Within the Delaware River region, these fish were not merely sustenance but also integral to the fabric of indigenous Lenape culture. During the annual shad migration, rivers and streams overflowing with these prized fish provided essential nourishment and served as valuable fertilizer. Interestingly, in various Native American tribes, folklore depicts the shad as originating from the porcupine, likely owing to the fish's notably bony structure.
In later American history, the significance of shad persisted. Renowned painter Thomas Eakins immortalized the tradition of shad fishing in his iconic 1881 masterpiece "Shad Fishing at Gloucester on the Delaware River," while the state of Connecticut elevated the shad to the status of state fish, further cementing its place in American heritage.
Fishing for American shad was among the earliest established industries on the coast of North America, once providing abundant and affordable nutrition to the populace. However, the shad population peaked in the 1940s before experiencing a dramatic decline to its current depleted state.
Despite these challenges, the American shad perseveres as a symbol of resilience. Festivals along the Atlantic Coast, such as the Annual ShadFest in Lambertville, New Jersey, celebrate these fish while also advocating for their protection. Recognizing the historical importance of shad underscores the pressing responsibility to safeguard and preserve our natural heritage for future generations.
The construction of dams, historic overfishing, and pollution have all played significant roles in the decline of American shad populations.
Dams along the East Coast block access to vital spawning grounds. Currently, a staggering 40% of American shad habitat is obstructed by these barriers, resulting in the loss of more than a third of the population. By removing outdated dams that have outlived their usefulness, we not only improve water quality and natural habitat for myriad species but also reconnect shad to their historic spawning grounds.
Additionally, shad fall victim to inadvertent bycatch in various ocean fisheries. Pollution in our rivers and water quality issues emerge as another critical concern along with fluctuating water temperatures and dissolved oxygen levels that disrupt shad behavior and crucial life cycle events such as migration and spawning. Compounding these issues are the menacing presence of invasive species, which outpace shad in numbers and deplete food resources, posing a significant obstacle to their recovery efforts.
Amidst these challenges, there is hope. River restoration efforts, dam removals, and fish passage projects throughout the East Coast stand as beacons of progress.
Removing obsolete dams, culverts, and other man-made barriers; the implementation of fish passage projects; and river habitat restoration initiatives have shown promising results in directly aiding shad and other migratory aquatic species populations. Highlighted below are a few examples of dam removal initiatives that immediately yielded positive results:
The Nature Conservancy in New Jersey and Princeton Hydro are leading the removal of three outdated dams on the Paulins Kill River: the Columbia Lake Main and Remnant Dams (completed 2019), the County Line Dam (completed 2021), and Paulina Dam (slated for completion 2024). This collaborative effort will reconnect 45 miles of mainstream and tributaries for migratory fish species like American shad. The Columbia Lake Dam removal, New Jersey's largest to date, began in July 2018 and showed promising results even before 100% completion. By April 2019, American shad were spotted 10 miles upstream from the former dam site for the first time in over a century, showcasing the resilience of this incredible species and the success of conservation initiatives.
In November 2016, the Musconetcong Watershed Association (MWA) and Princeton Hydro completed the Hughesville Dam Removal, opening up six miles of the Musconetcong to migratory fish. In the Spring of 2017, schools of American shad were observed above the dam, five miles from the river's confluence with the Delaware River. After an absence of over 250 years, American shad made a triumphant return to the Musconetcong River sparking hope for the future.
Shad serve as a crucial benchmark species, offering valuable insights into the ecological health and diversity of our waterways. Conservation endeavors that facilitate the resurgence of the American shad not only represent a thrilling triumph but also stand as proof-positive of our capacity to assist migratory fish in reclaiming their natural habitats. In doing so, we safeguard their future and preserve the places they call home.
By understanding the biology, historical significance, and primary challenges of the American shad, we can work towards sustainable solutions that benefit both shad populations and the broader ecosystem. We invite you to delve deeper into the fascinating world of American shad by watching the full webinar:
Nestled within the New Jersey townships of Hamilton, Robbinsville, and West Windsor lies Miry Run Dam Site 21—an expansive 279-acre parcel with a rich history dating back to its acquisition by Mercer County in the late 1970s. Originally earmarked for flood mitigation and recreation, this hidden gem is on the cusp of a remarkable transformation, poised to unveil its true potential as a thriving public park.
Central to the revitalization efforts is a comprehensive Master Plan, meticulously crafted by Mercer County Park Commission in partnership with Simone Collins Landscape Architecture and Princeton Hydro. This visionary roadmap encompasses a spectrum of engineering and ecological uplift initiatives, including:
The Master Plan serves as a long-term vision for improvements to the property and will be implemented over multiple phases. In 2021, it was recognized with the Landscape Architectural Chapter Award from the New Jersey Chapter American Society of Landscape Architects, which underscores its innovative and impactful approach to landscape design.
Now, Dam Site 21’s revitalization has begun with a crucial endeavor: the dredging of its 50-acre lake. This process, spearheaded by Mercer County Park Commission in collaboration with Princeton Hydro, aims to rejuvenate the water body by removing accumulated debris, sediment, and invasive vegetation—a vital step towards restoring its ecological balance. Beyond the aesthetic and ecological improvements, dredging enhances accessibility for recreational activities that provide an opportunity to create a deeper connection between the park’s visitors and its beautiful natural landscape.
Based on the bathymetric assessment, which the Princeton Hydro team completed as part of the Master Plan, the dredging efforts are focused on three primary areas: Area 1 is located in the main body of the lake just downstream of Line Road and will generate approximately 34,000 cubic yards of dredged material; Area 2, which has approximately 4,900 cubic yards of accumulated sediment is located in the northeast cove, just north of Area 1; and Area 3, the northwestern cove, entails the removal of approximately 7,300 cubic yards of accumulated sediment.
Before the dredging work could begin, the Princeton Hydro team was responsible for providing a sediment sampling plan, sample collection and laboratory analysis, engineering design plan, preparation and submission of all NJDEP regulatory permitting materials, preparation of the technical specifications, and bid administration. Currently, our team is providing construction administration and oversight for the project.
The journey towards Dam Site 21's revival has been marked by meticulous planning, design, and community engagement spanning several years. With the commencement of dredging operations, the project's vision is gradually materializing—a testament to the dedication of all stakeholders involved. As the first phase unfolds, anticipation mounts for the realization of a vibrant, inclusive public space that honors both nature and community.
As Dam Site 21 undergoes its metamorphosis, it symbolizes not just a physical restoration, but a renewal of collective vision and commitment. Ultimately, Dam Site 21 isn't just a park—it's a testament to the enduring legacy of conservation, community, and the transformative power of restoration.
The significance of Dam Site 21's transformation extends far beyond its recreational appeal. It embodies a commitment to environmental stewardship, with measures aimed at bolstering flood resilience, improving water quality, and nurturing diverse wildlife habitats. By blending conservation with recreation, the project strikes an important balance between creating access for community members to enjoy the space and ecological preservation that puts native plants, critical habitat, and wildlife at the forefront.
To learn more about the restoration initiative and view the Final Master Plan, visit the Mercer County Park Commission’s website. Click here to learn about another one of Princeton Hydro’s recent restoration efforts. And, stay tuned here for more Mercer County Park Commission project updates!
The Paulins Kill River, New Jersey’s third largest tributary to the Delaware River, recently marked a significant milestone in its journey to restoration. On November 24, a crucial step was taken with the notching of the Paulina Lake Dam, signaling a pivotal moment in the effort to return the river to its natural state. This initiative, led by The Nature Conservancy (TNC) and supported by a collaborative effort among several organizations, aims to restore the Paulins Kill River ecosystem, improve water quality, and allow native aquatic species to migrate freely.
Located in Blairstown Township, Warren County, the Paulina Lake Dam has posed challenges to both the river's health and surrounding communities. It was originally constructed 128 years ago to produce hydropower, but has not functioned in that capacity for more than 50 years. Delaware River tributaries do not have the necessary size or flow to meet even a fraction of modern energy needs.
The 13-foot-high, 207-foot-long timber crib, rock-filled structure is classified as a Class II, Significant Hazard Dam due to its proximity to the Township of Blairstown. Its removal or rehabilitation became necessary to mitigate risks to life and property. Additionally, the dam has impeded fish passage along the Paulins Kill River, impacting the habitat for native brook trout and migratory species.
The dam removal and subsequent bank stabilization aims to reconnect over 7.6 miles of mainstream and tributary habitat along the river, and improve aquatic and terrestrial connectivity, improve surface water quality, enhance recreation and public safety, and eliminate the risk of a potential unplanned breach. The removal of the dam will also reconnect upstream and downstream populations of the endangered dwarf wedge and triangle floater mussels while increasing river ecology and public recreation.
Spearheaded by TNC in partnership with Blairstown Township, New Jersey Department of Environmental Protection’s Office of Natural Resource Restoration and Division of Fish and Wildlife, the U.S. Fish and Wildlife Service, Princeton Hydro, and Riverlogic-Renova Joint Venture, the project received funding through grants to support the removal of the Paulina Lake Dam. The Office of Natural Resources Revenue (ONRR) awarded a grant to TNC to fund a substantial portion of the removal through the Paulins Kill and Pequest Watershed Natural Resource Restoration Grant Program.
TNC recently completed preliminary notching of the 128-year-old Paulina Lake Dam. From November 24 through December 1, contractors from the Riverlogic-Renova Joint Venture worked in the river using heavy equipment to successfully remove a 40-foot long, six-foot high section of the structure, enabling a controlled release of the water impounded behind it.
Notching is performed to dewater gradually, preventing large amounts of sediment from flowing downstream all at once and potentially harming habitat. The gradual deconstruction ensures the river's stability and minimizes environmental disruption. The project team made subsequent reductions of the dam's height by one foot each day, totaling a six-foot reduction. Complete removal of the dam is slated for July through September of 2024.
Reporters from WFMZ 69 News visited the dam removal site to witness the first notch and talk with State Director of TNC in New Jersey Dr. Barbara Brummer, Blairstown Mayor Rob Moorhead, Director of Freshwater Programs at TNC in New Jersey Beth Styler Barry.
“Rivers remember,” said Beth Styler Barry, Director of Freshwater Programs at The Nature Conservancy in New Jersey. “The instant the first notch was made we could already see the Paulins Kill transforming into a more natural shape. Now with six vertical feet taken out, the water that has been stagnant for more than a century is flowing, cooling and aerating, and the natural floodplains are once again exposed and ready to revegetate.”
Click below to watch the full interview:
Princeton Hydro, contracted by TNC to provide site investigation, engineering design, permitting, and construction oversight services for the dam removal, has been working closely with Riverlogic-Renova Joint Venture to complete the deconstruction process.
"The first day of dam demolition is always exciting; seeing the river flowing through the breached Paulina Lake Dam after the first notch was very rewarding," said Paulo Rodriguez Heyman, Managing Member of the Riverlogic-Renova Joint Venture, the team leading the construction for the project. "Removing a high-hazard dam is challenging and requires the unique expertise of working in a dynamic river system. We are honored to be part of this collaborative team."
The removal of the Paulina Lake Dam stands as one integral facet of a larger restoration plan initiated in 2013, envisioning the removal of multiple dams along the Paulins Kill River. In removing the Paulina Lake Dam, the downstream-most dam on the Paulins Kill, TNC continues to build upon previous watershed-wide restoration activities that includes removing four dams: the Columbia Lake Main and Remnant Dams (2019), the County Line Dam (2021), and now the Paulina Lake Dam.
This multi-pronged effort includes wetland restoration, land protection, and floodplain reforestation—with more than 60,000 trees planted to date throughout 130 acres of floodplain. TNC has executed a 10-year “measures and monitoring” program, which began in 2016, to track conservation successes. This comprehensive effort brings hope for a rejuvenated and thriving river environment.
“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,” said Geoffrey M. Goll, PE, President of Princeton Hydro and Engineer-of-Record for the Paulina Dam removal project. “As a mission driven firm, we seek out projects that will have a positive ecological impact. We are proud to share that three of the dam removals that we designed on the Paulins Kill - Paulina Lake Dam, Columbia Lake Dam, and County Line Dam - will reconnect 45 miles of mainstem and tributaries for targeted migratory fish species like American shad, American eel, and sea lamprey.”
The Paulina Lake Dam Removal will be the final step in the TNC-led restoration of the lands and waters of the Paulins Kill.
As the restoration journey continues, it stands as a testament to the power of collaboration, environmental stewardship, and the dedication of communities and organizations striving to preserve and restore our natural landscapes.
Princeton Hydro President and Founding Principal Geoffrey M. Goll, P.E. was recently featured on the Native Plants, Healthy Planet Podcast, which is ranked as a Top 20 Nature Apple podcast with 7k+ listeners per month.
Hosts Fran Chismar and Tom Knezick, owners of Pinelands Nursery, invited Geoff on the show to discuss all things dam removal. For Episode 187 titled "The Dam Show" Geoff shared the history of dams and dam removal, the many benefits of removing dams, the challenges around implementing dam removal, recent stories of river restoration success, and helpful resources for anyone looking to learn more.
Princeton Hydro has designed, permitted, and overseen the removal of 84 dams to date. The firm was formed in 1998 with the specific mission of providing integrated ecological and engineering consulting services. Offering expertise in natural resource management, water resources engineering, geotechnical design and investigation, and regulatory compliance, their staff provide a full suite of environmental services throughout the Northeast for the public and private sectors. Princeton Hydro is committed to improving our ecosystems, quality of life, and communities for the better.
The removal of Beatty's Mill Dam stands as a pivotal moment in the conservation efforts along the Musconetcong River. This critical initiative, spearheaded by the Musconetcong Watershed Association (MWA), Washington Township, and the Town of Hackettstown in collaboration with Princeton Hydro and RiverLogic Solutions, marks a significant stride towards rejuvenating the river's natural ecosystem and addressing long-standing concerns regarding flood mitigation and habitat preservation.
Beatty's Mill Dam straddles the border between Warren and Morris Counties in Hackettstown and Washington Township, New Jersey. It is a 6-foot-high stone masonry, concrete, and earth embankment dam that was built in the 18th century and has been non-functional for decades.
Beatty’s Mill Dam is a low-head dam, which means it was not built to protect communities from flooding and can make flooding worse in some cases. Hackettstown and Washington Township are also more susceptible to flooding and erosion due to the high percentage of impervious surfaces, like roads and parking lots, which cause higher flows of stormwater runoff.
A dam safety report from 1981 shows that the dam had been breached on the eastern end. The breach caused a hairpin turn where the river is diverted sharply to the east then back to the west before flowing under the East Avenue bridge. Over time, this created erosive conditions at the upstream side of the bridge and roadbed, threatening the integrity of the infrastructure. Additionally, extensive alteration of the floodplain occurred upstream of the dam, including an elevated earthen berm along the left bank, and general land disturbance in both upland and wetlands.
The removal of the dam not only addresses the structural concerns but also holds the promise of extensive environmental improvements. By eradicating barriers to the Musconetcong River's natural flow, restoring the floodplain, and implementing strategies to curb stormwater runoff, this initiative aims to mitigate flooding, promote water quality, and foster a thriving habitat for aquatic organisms including indigenous species like the Eastern Brook Trout and American Eel.
With funding from the Highlands Council, Princeton Hydro was contracted in 2019 by Washington Township to complete a water quality assessment, hydrologic and hydraulic analysis, and functional value stream assessment of reaches of the Musconetcong River that encompassed the Beatty’s Mill site (and the downstream Newburgh Dam site). Following the New Jersey Highlands Water Protection and Planning Council guidance, Princeton Hydro assessed and rated the river reaches on five functional values: channel integrity, habitat, water quality, temperature moderation, and public use. The Beatty’s Mill Dam, floodplain encroachment, narrow riparian buffers, and non-native riparian vegetation were the primary sources of impact to the functional values.
Subsequently, Princeton Hydro was contracted by MWA to complete a site investigation, wetland delineation, topographic survey, and preliminary (60%) engineering design for dam removal. Preliminary plans were reviewed by Washington Township and the Town of Hackettstown. In 2023, Princeton Hydro completed the final engineering design, hydrologic and hydraulic modeling, and permitting for the removal of Beatty’s Mill Dam and restoration of the floodplain and provided engineering oversight during construction.
The removal of Beatty’s Mill Dam was officially completed the week of November 13, 2023!
Princeton Hydro assisted in the removal and restoration, providing engineering plans and project management support. With the dam removed, 2.5 acres of flood plain have been restored; 0.15 mile of stream bank have been stabilized; 0.15 mile of stream bed has been rehabilitated; and total suspended solids in the water have been reduced by 20%.
Michael Allers, Princeton Hydro Restoration Ecologist and licensed FAA-Certified Commercial Drone Pilot, captured these aerial images of the completed project site:
It is projected that there will be significant improvement to the five aforementioned functional values, increased fish passage, enhanced hydraulic conditions at the East Avenue bridge as well as improvements to the river’s pH, temperature, and dissolved oxygen levels.
Removing the dam also supports conformance with the Highlands Regional Master Plan, which is intended to protect, preserve, and enhance precious water resources within the Highlands Region. The project work also includes the restoration of the damaged floodplain, stream banks, and stream bed by planting trees, building up the banks with rocks, and allowing the river to return to its natural flowing channel.
This project’s significance extends beyond the immediate environmental impact. Funding from sources like the National Fish and Wildlife Foundation under the Delaware Watershed Conservation Fund and New Jersey’s Highlands Council, along with corporate contributions, underscores its potential to serve as a model for similar restoration projects across the Delaware River Watershed. Such initiatives not only enhance aquatic habitats but also bolster community resilience against flooding and elevate public awareness regarding watershed conservation.
The vision for this restoration effort reflects a collective commitment to revitalize river ecosystems, not just for the immediate region but as part of a broader strategy for conservation. The Beatty's Mill Dam marks the MWA's sixth dam removed on the Musconetcong River since 2008, but it is far from the last. This project aims to set a precedent for sustainable river management and ecosystem preservation.
The removal of Beatty's Mill Dam represents a milestone in the ongoing efforts to restore the Musconetcong River's ecological balance and underscores the collaborative spirit between MWA, local municipalities, various stakeholders, and Princeton Hydro. It serves as a testament to the potential of concerted conservation endeavors to restore the vitality of our waterways and safeguard the natural heritage for generations to come.
The Musconetcong Watershed Association (MWA) is an independent, nonprofit organization dedicated to protecting and improving the quality of the Musconetcong River and its watershed, including its natural and cultural resources. Members of the organization are part of a network of individuals, families, and companies that care about the Musconetcong River and its watershed, and are dedicated to improving the watershed resources through public education and awareness programs, river water quality monitoring, promotion of sustainable land management practices, and community involvement. Click here to learn more.
Princeton Hydro has been working with MWA in the areas of river restoration, dam removal, and engineering consulting since 2003. Click here to read our Client Spotlight blog featuring MWA’s Executive Director Cindy Joerger and Communications Coordinator Karen Doerfer.
An extraordinary effort is underway in the Hudson River Valley—the removal of the Maiden Lane Dam. The towering 25-foot concrete structure, originally built for aesthetic purposes on a tributary to the Hudson River, has been impairing aquatic life and causing an array of negative environmental impacts since its construction in the early 1900s. Now, it is the focus of a project that promises to restore vital aquatic habitats.
Join us as we take a deeper look at the Maiden Lane Dam Removal project, an initiative that has been in the planning phase for nearly five years.
Located in the Town of Cortlandt on Furnace Brook, a tributary of the Hudson River, the Maiden Lane Dam was originally built by the former owners of McAndrews Estate. Unlike many dams throughout the country constructed with the primary goals of flood control, hydroelectric power, agricultural irrigation, or navigation of boats, the Maiden Lane Dam was built for aesthetic purposes. Yet the dam's impact extended well beyond its appearance.
The Maiden Lane Dam is the very first dam that fish and aquatic species encounter on Furnance Brook while attempting to travel up the Hudson River to reach foraging habitats and ancestral spawning grounds. The antiquated, unused dam poses a variety of risks to the wildlife restricted by the dam, people who live and recreate near the dam, and the environment surrounding the dam.
McAndrews Estate, along with the dam, was abandoned in the 1960s, and subsequently, Westchester County Parks assumed control of it. Shortly afterwards, the property was condemned.
In 2021, Princeton Hydro secured a contract with Westchester County to develop and finalize the dam removal engineering plans, secure permitting, and facilitate construction bid procurement. The project work also entailed collecting and analyzing sediment samples, conducting geomorphic assessments, and completing an in-depth hydraulic and hydrologic analysis focusing on potential flooding impacts. The collaboration with key stakeholders, including NYSDEC, Westchester County, and the Town of Cortlandt, ensured the feasibility of this ambitious dam removal endeavor.
The collaboration and careful planning set the stage for the much-anticipated removal of the Maiden Lane Dam.
The significance of this project cannot be overstated. Beyond its historical and ecological significance, the Maiden Lane Dam removal will reconnect approximately 1.5 miles of habitat for fish and other aquatic species. It represents a promising chapter in the ongoing efforts to revitalize Hudson River Valley streams and conserve the region's diverse fish and wildlife.
As we eagerly await the completion of the Maiden Lane Dam removal, the vision of restored aquatic habitats and thriving ecosystems shines brightly on the horizon. The journey of the Maiden Lane Dam Removal project is a testament to dedication, collaboration, and the unwavering commitment to the preservation of our natural environment.
Princeton Hydro team members Jake Dittes, PE and Duncan Simpson, PWS presented on Hudson Valley Dam removal during the 2023 National Stream Restoration Conference, hosted by the Resource Institute, a nonprofit organization dedicated to the restoration of America's precious waterways. The event, themed "Stream Restoration 2023: Finding Common Ground,” served as an inspiring backdrop for the broader narrative of stream restoration, showcasing the importance of projects like the Maiden Lane Dam removal in preserving our natural treasures.
The Maiden Lane Dam Removal is part of a larger effort, led by Riverkeeper, to restore migratory fish pathways and fisheries in the Hudson River Watershed.
Princeton Hydro has designed, permitted, and/or overseen the removal of 80+ small and large dams in the Northeast. To learn more about fish passage and dam removal efforts in the Hudson River Valley, click here. To learn more about our engineering services, click here.
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