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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.
Princeton Hydro is excited to announce that the Musconetcong Island Park Project received the New Jersey Future 2024 Smart Growth Award. This project, led by the Musconetcong Watershed Association (MWA), transformed a crumbling, long-abandoned laboratory into a vibrant, accessible riparian park space that provides opportunities for fishing, wading, paddling, and viewing wildlife in Bethlehem Township, NJ.
The site, which once housed a two-story concrete block laboratory used by the Asbury Graphite Mill, had become a hazard after decades of disuse. Located on a quarter-acre island in the Musconetcong River, the building was not only structurally unsound but also in the floodway of the River, posing ongoing risks to the surrounding environment. Through a collaborative, multi-year effort, the abandoned building was demolished, the area was restored, and the island was transformed into a welcoming, accessible space for public enjoyment and recreation.
The image below shows the old stairway, laboratory building, and island space with a white outline depicting the project area:
The Musconetcong Island Park Project represents a successful collaboration among numerous partners. Led by MWA, the project involved National Fish and Wildlife Foundation, the Township of Bethlehem, Harrington Construction, and Princeton Hydro.
Princeton Hydro provided engineering and environmental consulting services for the project. Our scientists and engineers completed all necessary permitting, designed both the conceptual and final restoration plans, and oversaw construction throughout the project.
Funding for the project was secured through three primary sources: New Jersey Green Acres Program, National Park Foundation, and U.S. Fish and Wildlife Service’s Delaware Watershed Conservation Fund. These grants were instrumental in facilitating the transformation of an industrial relic into a thriving park space, balancing the preservation of the river's natural resources with the creation of an accessible community destination.
The two-story concrete block building that once stood on Musconetcong Island was originally the Asbury Graphite Mill laboratory, constructed between 1925 and 1940. It was built on the foundation of a woolen factory that had been destroyed by fire in 1881. The laboratory was used for testing graphite, an inert and non-toxic mineral primarily used for lubrication and other industrial applications. Graphite refining began in Asbury in 1895, when Harry M. Riddle purchased the existing mills and converted them for this specialized purpose.
By the early 1980s, the laboratory was abandoned due to frequent flooding and a lack of modern plumbing. Despite its industrial history, the building had become a safety and environmental concern due to its floodway location and deteriorating condition. In 1999, the laboratory building was donated to the Musconetcong Watershed Association, who then initiated efforts to restore the site and transform it into a valuable public resource.
Today, the island has been transformed into a place where residents and visitors can enjoy the Musconetcong River. With improved access, new stairways, and interpretive signage sharing the history of the area, Musconetcong Island Park is a prime example of how thoughtful design can blend environmental restoration with community-focused development.
“We are honored to have contributed to the transformation of Musconetcong Island Park and proud to see this project recognized with a New Jersey Future Smart Growth Award for its role in enhancing the Musconetcong River Watershed. It reflects our commitment to sustainable design and the power of collaboration in creating lasting, positive impacts for both the environment and the community. It’s truly a win-win — removing an obstruction from the floodway while providing public access to the river,” said Geoffrey M. Goll PE, President of Princeton Hydro.
Since 2002, the New Jersey Future Smart Growth Awards have celebrated the best examples of sustainable planning and development across the state. The Musconetcong Island Park Project exemplifies these values by enhancing public access to nature, improving resilience to flooding, and fostering sustainable recreation opportunities in the heart of Bethlehem Township. The project showcases the importance of balancing environmental restoration with community needs, creating a space where people can connect with nature while preserving and protecting it for future generations.
The 2024 New Jersey Future Smart Growth Awards recognize six outstanding projects that exemplify innovative and sustainable development. This year’s award ceremony and celebration took place yesterday at the New Brunswick Performing Arts Center.
Click here to learn more about the awards and to view the full list of 2024 Smart Growth Award recipients.
MWA is an independent, nonprofit organization dedicated to protecting and improving the quality of the natural and cultural resources of the Musconetcong River and its Watershed. 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. Explore how the partnership between Princeton Hydro and the MWA led to the historic return of American shad to the Musconetcong River for the first time in over 250 years, revitalizing the ecosystem—read the full story here!
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.
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:
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:
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.
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.
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.
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.”
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.
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.
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.
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.
Welcome to the latest edition of our “A Day in the Life” blog series. Today, we explore the vibrant and creative world of landscape design through the eyes of Angelica Diaz, one of Princeton Hydro's talented Landscape Designers.
Landscape design is the discipline of organizing and modifying the features of a landscape to achieve a functional, biodiverse and visually appealing outdoor space. This process considers various factors such as climate, soil, topography, existing vegetation, and the intended use of the area. By integrating artistic and scientific principles, landscape designers develop plans that create harmonious and practical environments. These plans serve as a blueprint for projects, guiding the installation and maintenance of outdoor spaces while aiding in material selection and cost estimation.
Join us as we accompany Angelica on a day dedicated to the Trenton South Ward Community Garden project. This journey highlights her dedication to transforming natural spaces and her integral role in bringing our clients' visions to life. From client meetings and visioning sessions to detailed site analysis and creative design, Angelica's expertise showcases the diverse services and innovative solutions that Princeton Hydro offers in landscape architecture.
Let’s dive into the roots of her day!
This morning, Angelica begins her day at the Trenton Headquarters Office, preparing for a kickoff meeting with the Trenton South Ward Neighborhood Association (TSWNA) board, a voluntary organization of residents who work together to improve and maintain the quality of life of the south ward district of Trenton, New Jersey. This initial meeting is crucial for understanding the client’s goals and visions. Angelica is particularly excited about this community-driven project because she enjoys the inclusivity and creativity it fosters.
“Community projects are fantastic because they help people realize their creative vision and foster a sense of ownership,” says Angelica. “It’s important to have a visioning meeting to gather a wide range of thoughts and ensure everyone feels included.”
During the kickoff meeting, Angelica and the Princeton Hydro project team listen attentively to board members, taking notes and asking questions to clarify the client's vision. Together with the client, the project team brainstorms ideas, establishes clear deliverables, and discusses expectations for the project ahead. The team shared ideas for two sites in the neighborhood; one existing community garden and one undeveloped site across the street. At the Community Garden site, TSWNA has several vegetable garden beds and hosts community workshops that ecourage residents to get outside and learn the ins and outs of urban gardening. To make the space even more inviting and useful for the community, they discussed options like planting flowers, replacing the fence, and adding a storage shed.
Securing grant money can be the key to bringing your innovative project to life, but navigating the complex world of funding can be daunting. Princeton Hydro's Director of Marketing and Communications Dana Patterson Grear stumbled upon an ideal grant opportunity to kick-off the first phase of the TSWNA's vision for the exisiting Community Garden site. Facing a tight deadline, Angelica collaborated with Tyrell Smith, TSWNA Co-Founder/Board Chair, to submit an application to the Xerces Society for Invertebrate Conservation's Mid-Atlantic Monarch And Pollinator Habitat Kit Program. This program distributes habitat kits containing native milkweed and various nectar plants to project partners ready to dedicate time, labor, and land for developing pollinator habitats in the Mid-Atlantic and New York City areas.
This year, the kits were tailored specifically for urban farms, community gardens, and other communal and educational spaces in urban settings, with a focus on benefiting historically underserved communities—a perfect match for TSWNA, which was selected to receive over 500 native plants to enhance their space and create a habitat for monarch butterflies.
With a clear, collective vision in mind, Angelica heads to a project site in Trenton’s South Ward Neighborhood to conduct a comprehensive analysis in preparation for the Community Garden.
Angelica arrives at 475 Lamberton Rd, ready to assess the critical physical and environmental factors necessary for the landscape design project. She meticulously observes sun exposure and soil characteristics to understand how these conditions could affect plant growth. She evaluates water availability, considering both natural sources and potential irrigation needs to ensure the sustainability of her design. The topography of the site is mapped out, identifying slopes, elevations, and natural drainage patterns that will influence the placement of features and the overall layout. All of these components help curate the overall aesthetic experience of the space throughout the day. Angelica takes photos, makes detailed notes of these observations, gathering essential information that will inform her design process and help create a harmonious and functional outdoor space.
“Site analysis is more than just understanding the immediate environment,” Angelica explains. “It’s about considering the broader context, including the surrounding neighborhood and city. This helps identify the project's needs and how it can best integrate with the local community. By working together, we can create a beautiful and sustainable space that benefits the Trenton community.”
Now it’s time for Angelica to draft initial concepts. Using a combination of AutoCAD, SketchUp, and Adobe Creative Suite, she begins to translate her site analysis and the client's feedback into visual designs. For the Trenton South Ward project, Angelica starts with a basemap created from field measurements and Google Earth imagery, evolving it into three distinct concepts.
“I aim to keep the concepts relatively loose at this stage,” she explains. “This helps get a reaction from the client and see which design they gravitate towards.”
Balancing aesthetics and sustainability, Angelica always prioritizes using a native plant palette, recognizing the seasonal characteristics and ecological benefits of native plants. She aims to create landscapes that are both beautiful and sustainable, supporting local wildlife and promoting biodiversity.
For this project, the plant selection came from the Xerces Society for Invertebrate Conservation. The Xerces Society supplied carefully chosen native and regionally appropriate plants from Pinelands Nursery in Columbus, NJ, one of the largest native plant nurseries in the US, supplying millions of plants for environmental restorations throughout the Mid-Atlantic states. Some of the native species selected for the community garden include Black-eyed Susan (Rudbeckia hirta), Wild Bergamot (Monarda fistulosa), Little Bluestem (Schizachyrium scoparium), and Purple Coneflower (Echinacea purpurea). These perennial, drought-resistant plants not only enhance the aesthetic appeal of the area but also offer crucial habitats for pollinators and birds, fostering a healthier and more balanced ecosystem.
“The final design is a refinement of the concept with more detailed planting plans and site measurements,” Angelica notes. “I often visit the site again to confirm measurements and document conditions to ensure accuracy.”
Of the three concepts Angelica and the Princeton Hydro team developed, TSWNA chose design concept three, which is pictured below:
The planning and design work culminated in a vibrant Community Garden, volunteer-powered planting event, which kicked off this initial phase of the revitalization of this space. Members of TSWNA, Princeton Hydro, and local volunteers came together to bring the collective landscape design vision to life, creating a thriving green oasis for the community to enjoy. Together, the group planted 550 native flowers and shrubs generously provided by the Xerces Society. Despite the heat, they worked collaboratively to turn the area into a beautiful, sustainable garden that benefits the entire Trenton community.
During the planting day, Angelica demonstrated proper techniques for preparing the ground for planting, installing plant plugs, and maintaining the space once all of the planting is complete. In the video below, Angelica demonstrates how to plant a plug in the ground:
Angelica always dedicates time to staying updated on the latest trends in landscape architecture, attending industry conferences, and connecting with colleagues to share insights and ideas. This continuous learning helps her bring innovative solutions to her projects.
“I’m excited about the growing trend of sustainability in landscape design,” she says. “Incorporating green infrastructure and eco-friendly practices is essential for a sustainable future.”
Reflecting on her day, Angelica acknowledges the unique challenges (and opportunities) of landscape design, from site constraints to fulfilling client expectations. She finds great satisfaction in overcoming these obstacles and seeing designs come to life.
“There’s no such thing as the perfect site,” she admits. “Each project comes with its own challenges, but it’s incredibly rewarding to see a space transformed and to know that it will thrive and bring joy to the community for years to come.”
Angelica's journey in landscape design began at Temple University, where she pursued her graduate studies. Her professional path includes valuable experience at a small residential landscape architecture firm that also owned a native plant nursery, providing her with extensive knowledge about plant names, identification, and growth habits. Prior to this, she worked at a landscape restoration company focusing on invasive species removal and management, enriching her understanding of both native and invasive plants.
With a lifelong artistic inclination and a profound appreciation for ecology and biology, Angelica found her perfect career blend in landscape design and architecture. Although she wasn't initially exposed to landscape architecture as a career option, her graduate program welcomed individuals from diverse backgrounds, helping her realize her passion for this field.
Angelica is particularly excited about the growing trend of resilience and sustainability in landscape architecture, especially in response to climate change. She looks forward to continuing her work on projects related to green infrastructure and stormwater management, and the multidisciplinary approach to restoring ecological function.
Princeton Hydro is an expert in engineering, ecological restoration, and landscape architecture, and we’ve been incorporating green stormwater infrastructure and nature-based solutions into our designs for decades. Recently, Princeton Hydro partnered with Congregation Kol Emet to design and implement a sustainable 10-acre campus transformation, providing green infrastructure engineering, landscape architecture, and construction services to enhance the synagogue's usability and welcoming atmosphere, reduce flooding, improve water quality, and augment biodiversity. Read more.
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 Brooklyn Bridge, a symbol of architectural excellence, spans the East River, connecting the vibrant boroughs of Manhattan and Brooklyn. Beyond its iconic presence, the construction of this masterpiece has a surprising connection to our firm. The roots of the Princeton Hydro headquarters building stretch back to the late 1800s; the first occupants of the building played a pivotal role in manufacturing and supplying the sturdy steel cables that formed the bridge's suspension system, an integral part of its enduring strength. Exploring the building's rich past, we discover a remarkable link to a legendary figure, bridging our current aspirations with the legacy of a woman who left an enduring mark on history.
The John A. Roebling's Sons Company was a wire rope manufacturing facility in Saxonburg, Pennsylvania founded in 1841. In 1848, the company relocated to Trenton, NJ along the Delaware & Raritan Canal and built a 25-acre complex of industrial buildings and facilities for wire rope manufacturing. This included the Carpenter's Shop (Building 110), the building that is now home to the Princeton Hydro's headquarters office, which manufactured specialty wooden products for the operation. The company quickly established itself as a notable employer in the city.
The company gained international recognition for its expertise in wire, wire rope manufacturing, and bridge building. Additionally, their products were extensively utilized in various industries, commercial sectors, and consumer goods. Over 112 years, four generations of the Roebling family successfully managed the business, a remarkable and uncommon accomplishment in the corporate world.
John A. Roebling, the company's founder, was renowned for inventing the wire rope, which revolutionized the way we build bridges. The wire rope (or steel cable) was innovative as it replaced the bulkier and weaker hemp fiber rope that was used to haul canal boats. He also developed a technique for spinning cables in place rather than constructing pre-fabricated cables that required maintenance before actually being used. This enabled him to become the world's foremost builder of suspension bridges in the 19th century, and his bridges spanned major rivers despite skeptics who believed such feats were impossible.
The Brooklyn Bridge construction started with an accident when the chief designer, John A. Roebling, had his foot injured by a ferry. He died of tetanus, and his son, Washington A. Roebling, who worked with his father on the Roebling Suspension Bridge over the Ohio River at Cincinnati and on the design of the Brooklyn Bridge, took over the project. Three years into construction of the longest suspension bridge in the world (at that time), Washington was incapacitated by "caisson disease." His wife, Emily Warren Roebling, took over and guided the completion of the bridge, which was one of the 19th century's most impressive architectural achievements. In honor of Women's History Month, we are spotlighting Emily Warren Roebling, whose groundbreaking contributions serve as an inspiring testament to the capabilities and achievements of women in history.
While Washington is widely credited for completing the Brooklyn Bridge in 1883, it's essential to equally acknowledge Emily's significant contributions. Her remarkable leadership, engineering acumen, and tireless dedication were pivotal in navigating the complexities of the Brooklyn Bridge's construction, ensuring its successful completion and solidifying her legacy as an engineering pioneer.
In his book "The Great Bridge," historian David McCullough describes Emily's multifaceted role as both a nurse and private secretary to her husband, taking over his correspondence and record-keeping. Additionally, she actively engaged in the bridge's construction, reviewing plans, visiting the site, and interacting with contractors and bridge officials. McCullough aptly summarized her contributions, stating that she served as "his eyes, his legs, his good right arm."
However, Emily's dedicated support also led to false rumors that her husband, Washington, had lost his mental faculties. Despite these challenges, Emily successfully fought to prevent Washington's removal as chief engineer nearing the bridge's completion. Washington, in turn, acknowledged his wife's invaluable contributions to the project. He later expressed his gratitude, acknowledging her as a "strong tower" and a wise counselor who supported him during difficult times.
Emily Warren Roebling's advocacy extended beyond her work on the Brooklyn Bridge with her husband. A pioneering figure of the early 20th century, Emily championed women's equality in education, ownership rights, legal matters, and philanthropic endeavors. She actively participated in women's clubs, contributed to the World's Columbian Exposition, and was nominated for the presidency of the Daughters of the American Revolution.
Her written papers addressed crucial topics such as philanthropy, settlement houses, and the importance of legal education for women. Her legacy continues to inspire, as a new generation of professional women, including lawyers and engineers, joined the suffrage movement after her demise in 1903. It is speculated that had she lived longer, she would have been a prominent leader in the women's suffrage movement. While her direct contributions remain unknown, the sight of female engineers proudly asserting their rights during rallies in academic attire would likely have brought a smile to her face. Emily's advocacy serves as a testament to the enduring power of equality, as subsequent generations of professional women carried her vision forward.
In our dynamic business landscape, we find inspiration in the tale of an extraordinary woman whose vision and tenacity shaped history. Her legacy reminds us that genuine success goes beyond material gains. It lies in the positive influence we leave on the world. Let us all strive to leave a lasting mark that echoes the timeless principles of integrity, resilience, and inclusivity.
The Watershed Institute hosted a webinar on Enhanced Stormwater Management Ordinances, which featured two expert speakers: Princeton Hydro Senior Technical Director of Engineering Dr. Clay Emerson, PE, CFM, and The Watershed Institute Policy Director Michael Pisauro, Esq. They provided guidance on NJDEP's new stormwater ordinances, a summary of requirements, and recommendations for developing and implementing stronger ordinances.
Co-sponsored by the American Littoral Society, Association of New Jersey Environmental Commissions, and Pinelands Preservation Alliance, the webinar was attended by officials, planning board members, municipal professionals (engineers and planners), attorneys and Environmental Commission members from all across the state.
In March 2020, NJ Department of Environmental Protection (NJDEP) published revisions to the New Jersey Stormwater Management Rule (N.J.A.C. 7:8), which states that, in order to meet stormwater management performance criteria set forth by NJDEP, New Jersey municipalities are required to update their stormwater control ordinances to incorporate green infrastructure. Check out our blog detailing the updated requirements.
NJDEP periodically updates the stormwater rules and provides municipalities with a deadline to incorporate the rule changes in order to stay in compliance. In July 2023, NJDEP published the Inland Flood Protection Rule, which requires municipalities to update their stormwater control ordinances to improve water quality. The Watershed Institute’s webinar, which was part of its “Technical Friday" webinar series, not only provided participants with a clear understanding of the recent rule updates and guidance on how to implement best practices, but also provided the opportunity for everyone to get their questions answered.
To view the full webinar, click below:
The Watershed Institute's next "Technical Friday" webinar, which is free to attend, will focus on "Stormwater Design: Myths and Misconceptions." One of the most complicated aspects of a new development application is designing the stormwater management infrastructure. It is also one of the most complex parts of reviewing applications before New Jersey’s land use boards. While stormwater management is a difficult and complex issue, it is vital to the health and wellbeing of New Jersey communities and residents. The state's 2023 Municipal Separate Storm Sewer System (MS4) permit puts front and center New Jersey's obligation to review the stormwater issues caused by land development. Better design submissions will assist in reaching this goal and may speed up the process of review and approval.
On December 8 from 10 am - 12 pm, join Gabriel Mahon, PE, Bureau Chief of the Bureau of NJPDES Stormwater permitting and Water Quality Management and Dr. Clay Emerson, PhD, PE, CFM from Princeton Hydro as they examine some of the common issues they uncover in stormwater management proposals and provide guidance on incorporating best practices and submitting designs that successfully address New Jersey's stormwater management goals.
The Watershed Institute, established in 1949, is a nonprofit organization located in Central New Jersey that promotes and advocates conservation and restoration of natural habitats, collects data on environmental conditions in its watersheds, and provides environmental education through numerous programs. To learn more about The Watershed Institute, click here.
At Princeton Hydro, we recognize the benefit of green infrastructure and we’ve been incorporating it into our engineering designs since before the term was regularly used in the stormwater lexicon. We are a leader in innovative, cost-effective, and environmentally sound stormwater management systems. The preparation of stormwater management plans and design of stormwater management systems for pollutant reduction is an integral part of our projects. Click here to read about an award-winning Green Infrastructure stormwater management & Floodplain Restoration project we completed on Blue Acres Property in Linden’s Tremley Point.
The New Jersey Department of Environmental Protection (NJDEP), U.S. Army Corps of Engineers (USACE), project partners, and elected officials broke ground on the interior cleanup of Liberty State Park in Jersey City (Phase 1A), marking a significant milestone in the history of New Jersey’s most visited state park.
During the groundbreaking ceremony, participants heard presentations from Commissioner of Environmental Protection Shawn M. LaTourette, USACE New York District Commander Colonel Alex Young, Assemblywoman Angela McKnight, and Assemblyman William B. Sampson IV.
As quoted in the press release distributed by the Murphy Administration, Commissioner LaTourette said, “Today’s groundbreaking is a critical step toward building a future at Liberty State Park that brings people and communities together to enjoy the environment we all share. Through the cleanup and restoration of nearly 235 acres, we will reckon with the industrial pollution of our past and from it, create a world-class outdoor urban environment that will be enjoyed by many future generations.” Click here to read the full press release.
A long history of industrial contamination (also called legacy pollution) has left 235 acres of Liberty State Park fenced-off and inaccessible to the public for decades. The groundbreaking ceremony marks the official start of Phase 1A of the clean up and restoration project.
Princeton Hydro was contracted by USACE New York District in partnership with the NJDEP Office of Natural Resource Restoration to design a resilient coastal ecosystem within 235 acres of this highly urbanized setting that provides both ecological and social benefits. This includes the restoration of over 80 acres of tidal and non-tidal wetlands and creation of several thousands of feet of intertidal shoreline and shallow water habitat hydrologically connected to the Upper New York Bay. When constructed, this will be one of the largest ecosystem habitat restoration projects in New Jersey.
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.
At Princeton Hydro, our Geosciences Team consists of Geotechnical Engineers and Geologists who are proficient in the behavior of earth materials and the application of soil and rock mechanics. Together, they assess the physical, mechanical, and chemical properties of soil and rock to design solutions, assess risks, and solve problems for a diverse array of projects, including infrastructure, stormwater management, and coastal restoration.
Supporting Princeton Hydro’s Geosciences team is our full service, in-house materials testing laboratory that provides soils, rock, and construction materials testing. Soils intended to support structures, roadways, or other infrastructure must be evaluated by geotechnical engineers to predict their behavior under applied forces and variable moisture conditions.
Our Soils Testing Laboratory, located in Sicklerville New Jersey, is accredited by the American Association of State Highway and Transportation Officials (AASHTO) and validated by the United States Army Corps of Engineers (USACE) Materials Testing Center (MTC) to complete a full complement of tests. The AASHTO Accreditation Program is the largest accrediting body in the construction materials industry and most widely-accepted. The USACE MTC is the only agency authorized to validate commercial laboratories to work for the USACE. All of our laboratory testing is performed in accordance with applicable American Society for Testing and Materials (ASTM) standards.
For this edition of our "A Day in the Life" blog series, we opened the door to our geotechnical laboratory to walk you through “a day in the life” of our Soils Testing Lab expert Marissa Ciocco, P.E.
Let’s roll up our sleeves and dig in the dirt!
Each day looks a little different for Marissa depending on what types of samples require testing and what tests need to be performed. Our testing capabilities include grain size analysis, soil classification, moisture content, liquid and plastic limits, permeability, organic content, moisture-density relationships (Proctor), soil strength tests (UC, UU, CU, CD), and many others.
For Marissa, first on the to-do list is the task of determining the liquid limit and plastic limit of a soil sample. Collectively, alongside the shrinkage limit, these tests are referred to as the Atterberg limits. This classification test determines the water content at which fine-grained soils transition between four states: solid, semi-solid, plastic, and liquid.
Soil exhibits significant differences in strength, consistency, and behavior depending on which state the soil is in. The Atterberg limits test determines when the physical changes occur, and provides valuable insights into soil strength, permeability, settlement values, and expansion potential, all of which are incredibly important in all aspects of planning, engineering design, and implementation.
First, Marissa prepares the soil sample. The Atterberg limits test is only performed on soil material that can pass through a 0.425mm sieve (an ASTM requirement).
Watch Marissa perform elements of the D4318 test is titled "Liquid Limit, Plastic Limit, and Plasticity Index of Soils."
In the video, Marissa demonstrates the Liquid Limit test. She adds moisture to the test specimen by adding water and mixing with a spatula. She then spreads the sample into the brass bowl of the liquid limit device, uses a grooving tool and manual-crank, and (off camera) she proceeds to measure when the groove closes, which defines the soil’s liquid limit.
She also demonstrates the Plastic Limit test, which she does by rolling a small portion of the wet soil sample onto a glass plate, creating a thread of soil. In doing so, she determines the water content at which the soil thread crumbles before being completely rolled out. The plastic limit is defined at the water content where the soil thread breaks apart and cannot be re-rolled to a diameter of 3.2 mm. A soil is considered non-plastic if a thread cannot be rolled down to 3.2 mm at any level of moisture.
Next on Marissa’s to-do list is a soil compaction test referred to as a Modified Proctor test, which determines the relationship between a soil’s dry unit weight and water content. This test yields the optimal water content at which the soil sample will become most dense and achieve its maximum dry density.
Marissa first prepares the soil for testing by passing it through the appropriate sieve and mixing it with the appropriate amount of water as required by the testing parameters. The soil will be compacted into a specialized cylindrical mold, but first she weighs the empty mold to create a baseline.
The next step is to compact the moist soil into the mold. Soil is added in equal layers, and each layer is compacted by dropping a rammer of specific weight and length. The compacted soil specimen is then leveled, and the mass of the mold with compacted moist soil is measured. The compacted soil specimen is then extruded from the mold and the water content is measured. This process is repeated for multiple water contents and the results are charted to determine the optimum water content and maximum dry density.
Essentially, the test determines how much of the soil material can be compacted into the same volume at the various amounts of moisture. If soil is too dry, it cannot compress tightly due to particle friction. If the soil is too wet, it cannot compress tightly due to water absorbing the compactive effort. The compaction and Modified Proctor test help to indicate the stability of the soil and the load-bearing capacity of the soil, which is incredibly important for various types of engineering and construction projects.
A big thanks to Marissa for walking us through a portion of her day!
Marissa Ciocco, P.E., is a graduate of Rowan University holding a B.S. in Civil Engineering with a Bantivoglio Honors Concentration. She worked in the Construction Materials Laboratory as part of the CREATE's Fellowship program at Rowan University, and participated in clinic projects such as a green roof feasibility study, testing the effects of water quality on masonry mortar, and the sustainability of converting organic waste feedstock into liquid biocrude. Marissa is passionate about working towards creating a more sustainable environment.
Our team has provided sampling, testing, and qualification for a diverse array of projects and clients throughout the Northeast, including commercial, residential, and industrial applications. Our laboratory training, calibration, and quality control procedures ensure that testing is performed by competent, experienced personnel, like Marissa, utilizing properly calibrated equipment. And, our process ensures that the results are subjected to an exceptional quality control program.
Our Geosciences team, along with our in-house Soils Testing Laboratory, allows us to complete 100% of geotechnical site investigation, laboratory testing, analysis, engineering design, and reporting in-house. We can perform analyses for a multitude of geotechnical sub/specialized disciplines.
To read about a geotechnical investigation and soil borings analysis project we completed for the USACE New York District, click here. If you enjoyed this blog, check out another one from our “A Day in the Life” series, and stay tuned for more!
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