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Princeton Hydro and Cultivo recently collaborated in Southwest Montana to assess vegetation, wildlife, and other indicators of ecosystem health as part of a broader biodiversity monitoring initiative for a grassland restoration project. The blog offers an inside look at the monitoring methods used to establish a biodiversity baseline, highlights several unique species encountered during fieldwork, and examines the role of biodiversity and collaborative monitoring in supporting resilient landscapes and successful conservation outcomes. Beyond Carbon: Montana Grassland Biodiversity with Princeton Hydro Posted August 11, 2026 | Written by Sean Leslie, Cultivo Senior Manager of Content and Marketing When we think about nature-based solutions, carbon sequestration often steals the spotlight. But carbon is only one part of a much larger story. At Cultivo, we believe that restoring grasslands goes far beyond storing carbon underground; it’s about rebuilding complete, living ecosystems. True regenerative progress is measured in on-the-ground ecological health, and one vital metric of that health is biodiversity. Ecosystems rich in plant, bird, and insect life are proven to be more productive, more resilient, and better equipped to thrive. And just as we do when measuring and verifying sequestered carbon, to ensure our projects deliver measurable, lasting benefits in terms of biodiversity, we’re not relying on satellite images or computer models; we’re putting boots on the ground. Case in point: Cultivo’s Ecological Impact Senior Manager, Emiline Koopman, recently completed an intensive field visit to one of our partner sites in beautiful Southwest Montana. Alongside the expert field team at Princeton Hydro, she implemented our Biodiversity and Ecosystem Services (BES) monitoring framework across the landscape. Boots on the Ground: Why Field Visits Matter Virtual meetings and digital mapping are great for planning, but nothing replaces walking the land. And during the early summer pilot sampling campaign, Cultivo and Princeton Hydro did exactly that, deploying a full suite of monitoring techniques: Acoustic Recording Units (ARUs) and Bird Point Counts To monitor avian diversity, small weatherproof audio recording devices called Acoustic Recording Units (ARUs) are placed across the property to capture the natural soundscape – including bird calls – continuously over the summer breeding season. At the same time, ornithologists perform human “point counts” by standing quietly in one place for set time intervals with binoculars and clipboards to visually and auditorily record every species seen or heard. Together, these techniques provide a picture of species presence, relative abundance, and spatial distribution, acting as an indicator of overall habitat health. Vegetation Transects Measuring plant health and structure, requires laying long measuring tapes across the ground through a specific habitat type and placing square frames (quadrats) at fixed increments along the line. Along this path, researchers systematically count live and dead woody plant stems, measure canopy gaps, and catalog every plant species inside the quadrats, providing detailed ground-level data on plant species richness, ground cover, and pasture resilience. Malaise Traps and Flower Visitation Observations Insect populations are tracked and measured with Malaise traps, which resemble small, open-sided mesh tents with a collection jar at the top. Flying insects naturally bump into the traps’ fabric walls, fly upward, and are gathered for identification using conventional and eDNA metabarcoding techniques. To complement this, researchers also sit quietly near blooming native plants for timed intervals to perform insect flower visitation counts, tracking specific pollinators including bees, ants, and wasps. Meet the locals: Wildlife of Southwest Montana’s Grasslands One of the greatest rewards of field work is seeing firsthand what we are working so hard to protect. In Southern Montana, the team encountered an incredible array of flora and fauna. Here are a few of the standout species that call this ecosystem home, with pictures taken during the recent field visit: 1. Spearleaf stonecrop and Rocky Mountain parnassian [caption id="attachment_20316" align="alignleft" width="549"] Spearleaf stonecrop and Rocky Mountain parnassian. Photo Credit: Tanya Dapkey, CE, Princeton Hydro[/caption] On the high-elevation rangelands of Southwestern Montana, small native plants punch well above their weight. Among them, Spearleaf stonecrop (Sedum lanceolatum) is a tough, fleshy succulent that thrives in the rocky soils of our intermontane sagebrush valleys. It also happens to be the exclusive host plant for the Rocky Mountain parnassian (Parnassius smintheus), a high-altitude cousin in the swallowtail family. Female parnassians lay their eggs right next to stonecrop patches so hungry spring caterpillars can feed on the leaves. As they eat, the larvae absorb bitter chemicals from the plant, making both the caterpillars and the red-spotted adult butterflies completely unpalatable to birds, a classic example of the invisible, delicate connections that make these high-desert ecosystems work. 2. Brewer’s sparrow If any bird defines the vast sagebrush country of Southwestern Montana, it’s the Brewer’s sparrow (Spizella breweri). This small, inconspicuously plumaged songbird is intricately tied to healthy, intact rangelands. Brewer’s sparrows are sagebrush obligates, meaning they rely almost entirely on big sagebrush ecosystems for nesting, shelter, and feeding on insects and seeds. Their dull, streaked feathers provide perfect camouflage against native shrub leaves, while their long, breathy, trilling songs are a signature sound of spring on the range. Because they depend so heavily on large, unfragmented landscapes, healthy populations of Brewer’s sparrows are a key indicator of a thriving, well-managed rangeland ecosystem. 3. Thick-billed longspur [caption id="attachment_20313" align="aligncenter" width="588"] Thick-billed longspur. Photo credit: Eric Zawatski, CWB, Princeton Hydro[/caption] Where short prairie grasses like blue grama and buffalo grass break up the sagebrush valley, you’ll find the thick-billed longspur (Rhynchophanes mccowni). This species relies heavily on grazing to keep vegetation low; without livestock or bison disturbing the grass, their nesting habitat disappears. On their breeding grounds, they feed heavily on protein-rich grasshoppers. During springtime, males perform incredible aerial courtship displays: They fly up to 30 feet in the air and "parachute" back down on outstretched wings with their white tail feathers spread wide, singing a warbling song to impress females and mark their territory. 4. Pronghorn Pronghorn (Antilocapra americana) are gorgeous, iconic fixtures of Southwestern Montana's open valleys. While commonly referred to as "pronghorn antelope," they aren't true antelopes at all; their closest living relatives are actually the African giraffes and okapis. Built purely for acceleration and endurance, pronghorn are the fastest land mammals in the Western Hemisphere, topping out at speeds over 55mph, with this extreme speed attributed to a prehistoric evolutionary "arms race" with the now-extinct American cheetah (Miracinonyx). While modern wolves and coyotes can't come close to matching a pronghorn's pace today, these remarkable animals retain their incredible speed and massive heart-and-lung capacity, allowing them to cruise effortlessly across open rangelands. 5. Burrowing Owl [caption id="attachment_20312" align="aligncenter" width="543"] Burrowing owl. Photo credit: Eric Zawatski, CWB, Princeton Hydro[/caption] Small, long-legged, and undeniably cute, the burrowing owl (Athene cunicularia) is one of the range's most charismatic residents. Unlike most owls, these birds are diurnal, meaning they are active during the day and can often be spotted standing guard on fence posts or mounds. Burrowing owls have a fascinating relationship with prairie dogs and other underground mammals; because the owls can't dig their own homes, they rely entirely on abandoned burrows for nesting and shelter. These opportunistic hunters eat a wide-ranging diet that includes insects, small mammals, lizards, snakes, and birds. Highly sensitive to habitat loss, their presence is a great sign of an intact, biodiverse grassland. Collaborative Conservation in a Working Landscape Ranching landscapes are complex, working environments. During the visit, the team noted that this ecosystem is facing real-world challenges, including severe ongoing regional drought and water access issues. This is where our work regenerating the landscape becomes crucial; by combining rotational grazing strategies with targeted infrastructure improvements, we can significantly boost soil health, turning vulnerable land into a thriving, resilient ecosystem. According to the Natural Resources Conservation Service (NRCS), every 1% increase in soil organic matter lets an acre of land hold roughly 20,000 gallons of extra water. That moisture doesn't just keep pastures green longer during a dry spell, it also helps safeguard the land against wildfires. As research from the USDA and fire ecology experts shows, soils rich in organic matter maintain higher plant moisture levels and soil humidity, creating a natural firebreak that slows down fire spread and helps landscapes bounce back faster if a burn does occur. Hand-in-hand with our landscape restoration work, the ranch is actively participating in a broader ecological monitoring network, with ongoing research from local university programs and regional partnerships. Cultivo is actively working to coordinate with these existing initiatives, synthesizing data and supporting local land stewards. By pairing high-tech monitoring tools, on-the-ground data collection, and deep, generational knowledge of local ranchers, we can build restoration strategies that support both wildlife and agricultural livelihoods. Looking Ahead Implementing our Biodiversity and Ecosystem Services framework in Montana reminds us exactly why we do this work: to accelerate investment into nature and regenerate the world’s land into healthy, resilient ecosystems. As we refine our field protocols and analyze the baseline data gathered in Montana, we move one step closer to scaling transparent, high-integrity nature restoration worldwide. Stay tuned for more field updates as we continue monitoring biodiversity across our global project portfolio! Big thanks to Princeton Hydro's Mike McGraw, CSE, QAWB, ACE, Tanya Dapkey, CE, and Eric Zawatski, CWB, for providing photos and information for the species listed in this post! Click here to read this blog post on the Cultivo website. [post_title] => Guest Blog: Biodiversity Monitoring in Southwest Montana [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => guest-blog-biodiversity-monitoring-in-southwest-montana [to_ping] => [pinged] => [post_modified] => 2026-08-31 12:42:53 [post_modified_gmt] => 2026-08-31 12:42:53 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=20309 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 20032 [post_author] => 1 [post_date] => 2026-08-07 18:47:57 [post_date_gmt] => 2026-08-07 18:47:57 [post_content] => New Jersey Governor Mikie Sherrill signed Bill S3403/A4007 into law, requiring sellers to disclose the presence of dams on properties being sold in New Jersey along with information regarding the dams' condition, inspection history, hazard classification, and ownership obligations. The law is intended to improve transparency during real estate transactions and help buyers better understand the responsibilities that can accompany dam ownership before becoming contractually obligated to buy the property. For many, a waterbody can be an attractive property asset that enhances aesthetics, recreation opportunities, and property value. However, what is not always apparent is that the waterbody may be maintained by a dam, and ownership of that dam comes with legal, financial, and regulatory responsibilities. Because dams are regulated infrastructure, depending on their size and hazard classification, owners may be responsible for routine inspections, maintenance, repairs, emergency planning, and ongoing compliance with state regulations. In some cases, property owners do not discover the full extent of those obligations until after a real estate transaction is complete, resulting in unexpected costs and liabilities. "Dams are critical infrastructure, but they also have long-term responsibilities. Owners can face substantial costs associated with inspections, maintenance, rehabilitation, and regulatory compliance, and those obligations often transfer with the property purchase," explained Geoffrey M. Goll, PE, President of Princeton Hydro and NJ-licensed Professional Engineer. "This legislation helps ensure that prospective buyers understand the presence and condition of a dam so that they can evaluate those obligations upfront. Families and business owners can make informed investments while preventing unexpected liabilities, promoting public safety, and encouraging responsible stewardship of aging dam infrastructure across the state." The passage of S3403/A4007 follows months of advocacy led by The Nature Conservancy in New Jersey, which first proposed the legislation and worked closely with lawmakers, stakeholders, and bipartisan supporters throughout the legislative process. Through testimony, coalition building, and sustained engagement, the organization helped elevate awareness of the challenges and costs associated with dam ownership and the importance of providing prospective property buyers with clear and timely information. "No family should learn after purchasing a home that they have also assumed responsibility for a structure that could require extensive repairs or ongoing compliance costs," said Rebecca Hilbert, New Jersey Policy Associate at The Nature Conservancy. "By requiring transparency for buyers upfront, this legislation supports consumers, enhances public safety and helps ensure that dams affecting New Jersey's rivers and communities are responsibly managed." [gallery link="none" ids="11742,11313,12035"] Understanding the New Law Section 1 of the New Jersey Dam Disclosure Law states, "A seller of real property located in this State shall disclose, on the property condition disclosure statement, whether a dam is located within the boundaries of the property and any actual knowledge of the seller concerning the dam, as required pursuant to this section, to the purchaser before the purchaser becomes obligated under any contract for the purchase of the property." The law also adds specific dam-related questions to the property condition disclosure statement, including: Is there a dam located wholly or partially on the property? If so, what is the hazard classification for the dam? If current law requires the inspection of the dam, what are the results of the most recent inspection? If there are any obligations associated with the dam under State law for which a purchaser would assume responsibility for, what are the obligations? Additionally, the law directs prospective buyers to New Jersey Department of Environmental Protection (NJDEP) resources regarding dam ownership responsibilities, dam removal, and hazard classifications to gain a better understanding of the implications of dam ownership before becoming contractually obligated or completing the sale transaction. "Maintaining, repairing or replacing a dam can cost a lot of money. People deserve to know if they are purchasing property with a dam on it, and what obligations they have for that dam,” said Assemblyman Dave Bailey. “This bill could save a new homebuyer or business owner millions of dollars in unexpected future costs." Click here to read the full statutory language and implementation details of the New Jersey Dam Disclosure Law. [gallery link="none" ids="17568,13640,17566"] The Broader Impact of S3403 The law serves a broader public safety purpose. Better informed ownership can encourage compliance with dam safety requirements, timely maintenance and repairs, and informed decision-making regarding rehabilitation, dam removal, and river restoration. These responsibilities are not insignificant. Under New Jersey's Safe Dam Act and Dam Safety Standards (N.J.A.C. 7:20), regulated dams must be inspected by a qualified New Jersey-licensed Professional Engineer every two to four years, depending on the dam's hazard classification. Regulated dam owners are also required to maintain an Operation and Maintenance Manual, while Hazard Class I and II dams must have a NJDEP-approved Emergency Action Plan in place. A regulated dam is generally defined as an artificial dike, levee, or barrier that raises the waters of a stream more than five feet above the usual mean low water height. Many property owners may be unaware that these requirements apply to a structure on their property until they begin exploring its regulatory status or ownership obligations, or receive a compliance letter from NJDEP. These requirements exist to protect people, property, and the environment from the consequences of dam failures. When dams are not properly maintained, the impacts can extend far beyond the property boundary, potentially resulting in downstream flooding, property damage, environmental degradation, impacts to wildlife habitat, and, in the most severe cases, loss of life. By increasing awareness of dam ownership responsibilities before a property changes hands, the new law can help support safer, more proactive management of New Jersey's aging dam infrastructure while reducing the likelihood of unexpected costs and obligations for future owners. In a press release from The Nature Conservancy the organization stated, "The Nature Conservancy supported the legislation because dams can have lasting impacts on public safety, local communities and the health of New Jersey's waterways. Ensuring property owners understand their responsibilities is an important step toward informed stewardship of dams that affect both people and nature." We applaud The Nature Conservancy for spearheading this effort and building the bipartisan support needed to move the legislation from concept to law. We also thank Governor Sherrill, Senator John Burzichelli, Assemblyman Dave Bailey, Assemblyman Sterley S. Stanley, and the many legislators who recognized the importance of greater transparency for New Jersey homebuyers and businesses. Princeton Hydro has long supported proactive dam safety management, providing dam inspections, geotechnical investigations, regulatory guidance, rehabilitation planning, and dam removal services to property owners, municipalities, organizations, and regulatory stakeholders throughout New Jersey and beyond. For decades, Geoff has been a leading voice in dam safety and removal. Widely recognized for pioneering dam removal efforts in New Jersey and for his expertise throughout the United States and internationally, Geoff has spent more than thirty years evaluating dams and helping owners navigate complex regulatory and infrastructure challenges. To learn more about dam safety inspection, we invite you to read our recent blog, "A Day in the Life of a Dam Inspector: Casey Pantaleo, PE." [post_title] => New Jersey's New Dam Disclosure Law: What Property Buyers and Sellers Need to Know [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => new-jerseys-new-dam-disclosure-law [to_ping] => [pinged] => [post_modified] => 2026-08-11 13:48:18 [post_modified_gmt] => 2026-08-11 13:48:18 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=20032 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 20084 [post_author] => 1 [post_date] => 2026-07-22 20:00:47 [post_date_gmt] => 2026-07-22 20:00:47 [post_content] => Volunteers and community stakeholders gathered at Cupsaw Lake in Ringwood Township, NJ for the installation of two floating wetland islands, an innovative nature-based solution that improves water quality while enhancing biodiversity. The project was funded by Skylands Guardian, a nonprofit organization dedicated to protecting the natural resources of New Jersey's Highlands region through education, advocacy, and environmental stewardship. In partnership with Skylands Guardian, Princeton Hydro Aquatic Ecologist Katie Walston-Frederick led the hands-on installation event, which transformed native plants and recycled materials into living ecosystems designed to benefit the lake for years to come. A Nature-Based Solution for Cupsaw Lake Nestled within the Ramapo Mountains, Cupsaw Lake is a 65-acre freshwater lake in the heart of Ringwood Township. To help preserve its long-term ecological health, local partners continue to invest in innovative, science-based management initiatives. Floating wetland islands are one such solution. Constructed from recycled materials and planted with native vegetation, floating wetland islands are designed to mimic the functions of natural wetlands. Beneath the surface, extensive root systems create habitat for beneficial microbes that help remove excess nutrients from the water column while providing shelter and foraging opportunities for fish and other wildlife. The result is a floating ecosystem that supports water quality, biodiversity, and habitat enhancement all at once. Research has shown that a 250-square-foot floating wetland island can remove approximately 10 pounds of phosphorus annually while providing roughly the same nutrient-processing surface area as one acre of natural wetland. Considering that a single pound of phosphorus can generate up to 1,100 pounds of wet algal biomass, floating wetland islands have the potential to significantly reduce nutrient availability and help limit some of the factors that contribute to nuisance algal blooms. [caption id="attachment_4363" align="aligncenter" width="1475"] This illustration, sketched by Princeton Hydro Project Manager and Environmental Scientist Ivy Rose, PWS, conveys the functionality of a floating wetland island.[/caption] A Hands-On Community Effort A key component of the Cupsaw Lake project was community participation. Katie coordinated and directed the installation effort, guiding volunteers through each stage of the process. Participants learned how to prepare native plants, install plant plugs within the floating island matrix, apply protective goose netting, and properly deploy and anchor the islands within the lake. The event provided an opportunity for volunteers to learn firsthand about lake ecology, nutrient management, and the role innovative restoration tools can play in protecting local water resources. As the newly planted vegetation establishes itself in the coming months, the islands will become increasingly effective at nutrient uptake while creating a visually appealing focal point within the lake. Over time, the native plantings and submerged root systems will provide valuable habitat for fish, macroinvertebrates, and other wildlife. In addition to their environmental benefits, the islands will serve as a visible reminder of the community's commitment to protecting and enhancing Cupsaw Lake. [gallery link="none" size="large" ids="20130,20131,20129,20132,20137,20135"] [gallery columns="2" link="none" ids="20139,20138"] Part of a Larger Watershed Vision The project also aligns with broader watershed management efforts taking place throughout Ringwood and the New Jersey Highlands. In 2019, the Borough of Ringwood became the first municipality in New Jersey to pursue a regional approach to private lake management through a public-private partnership with four lake associations: Cupsaw, Erskine, Skyline, and Riconda. Situated within the northeast corner of the Highlands region, Ringwood is home to numerous lakes and reservoirs that provide drinking water to millions of New Jersey residents. To support the long-term protection of these resources, the Borough partnered with Princeton Hydro to develop a comprehensive watershed management plan that identifies and prioritizes projects that address both immediate and future water quality concerns. This approach recognizes that healthy lakes require more than in-lake management. Sustainable improvements depend on addressing nutrient and sediment sources throughout the surrounding watershed. And, organizations like Skylands Guardian play a critical role in turning watershed planning into on-the-ground action. Projects like the Cupsaw Lake floating wetland islands complement larger watershed initiatives by improving water quality, enhancing habitat, and fostering community engagement. More About Katie During her more than 11 years with Princeton Hydro, Katie has contributed to a wide range of water quality monitoring programs, fisheries investigations, habitat restoration projects, and watershed assessments. She serves as the firm's primary coordinator for floating wetland island projects and has overseen installations at waterbodies throughout the Mid-Atlantic. In 2017, she became certified as an Island Master Builder through Floating Island International, receiving specialized training in the design, construction, installation, and application of floating wetland island technology. Her expertise helped ensure that the Cupsaw Lake installation project not only achieved its technical objectives but also provided a meaningful educational experience for volunteers and community members. Click here to learn more about Katie. A special thank you to Skylands Guardian for documenting the installation and helping share the story of this exciting community-driven project. To learn more about the Skylands Guardian and how to support the great work they're doing, click here. To learn more about another one of Princeton Hydro's long-term lake management initiative, explore our blog, Two Decades of Lake Management Innovation at Duke Farms, which highlights efforts to protect and monitor the interconnected lakes and ponds across Duke Farms' 2,700-acre property in Hillsborough, New Jersey. [post_title] => Cupsaw Lake Welcomes New Floating Wetland Islands [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => floating-wetland-islands-cupsaw-lake [to_ping] => [pinged] => [post_modified] => 2026-07-22 20:00:47 [post_modified_gmt] => 2026-07-22 20:00:47 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=20084 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [3] => WP_Post Object ( [ID] => 19972 [post_author] => 1 [post_date] => 2026-06-24 22:08:28 [post_date_gmt] => 2026-06-24 22:08:28 [post_content] => When a dam is removed, what happens to all the sediment that has built up behind it? That question was the focus of a recent Dam Busters webinar led by Geoffrey M. Goll, PE, President of Princeton Hydro and an internationally recognized expert in dam removal and river restoration. During the session, Geoff shared insights on how sediment behaves during dam removal projects, how it accumulates behind dams, and how different materials such as sand, silt, and organic matter respond once the dam is removed. He also discussed the methods practitioners use to estimate how much sediment is likely to move, how quickly it will travel, and the risks it may pose downstream, along with the practical decisions project teams face, including when to rely on natural processes, when intervention is needed, and how to design a strategy that balances ecological benefits, cost, and potential impacts. Click here to watch the full webinar and explore the slide deck and additional resources. [embed]https://youtu.be/aQHGU0ha130?si=KJiZNCWSmBaj73Ld[/embed] Case Study: Paulina Lake Dam Removal Project During the webinar, Geoff highlighted a real-world example of a dam removal project that required careful sediment management: the Paulina Lake Dam removal on the Paulins Kill River in New Jersey. For this project, the team implemented a phased dam breach, gradually lowering water levels to control the release of sediment and allow the river to begin forming its new channel. A portion of the sediment, particularly the highly organic material near the dam, was actively removed to prevent downstream impacts, while the rest was allowed to mobilize naturally. To learn more about the Paulina Lake Dam removal project and see the transformation in action, click here to read our blog. [gallery link="none" ids="14028,17040,19110"] More About Dam Busters Dam Busters is an initiative created by the Mass Rivers Alliance in partnership with the Massachusetts Division of Ecological Restoration and the Charles River Watershed Association. Its mission is to provide dam removal stakeholders with the knowledge and tools needed to successfully support and implement projects. The program offers expert-led webinars with live Q&A, technical resources and guidance, site visits and hands-on learning opportunities, and in-person workshops and conferences. Whether new to dam removal or actively working in the field, Dam Busters provides valuable, expert-driven insights to help guide dam removal efforts. Click here to learn more and get involved. More About Geoff Geoffrey M. Goll, PE, a founding partner and the President of Princeton Hydro, has over 35 years of experience in water resources engineering, geotechnical engineering, and river restoration. He is widely recognized for advancing innovative and effective approaches to river restoration. Geoff holds a B.S. in Civil Engineering from Rutgers University, a Master of Engineering Management from the University of Wisconsin–Madison, and is a licensed Professional Engineer in 11 states. He pioneered dam removals for the purposes of fish passage in New Jersey and has overseen more than 50 dam removal designs. His understanding of sedimentation mechanisms and management of sediment behind impoundments has been instrumental in managing the mitigation of environmental impacts during and after demolition of river and stream obstructions. Click here to learn more about Geoff. [post_title] => WATCH NOW: Understanding Sediment Management for Dam Removal Projects [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => watch-now-understanding-sediment-management-for-dam-removal-projects [to_ping] => [pinged] => [post_modified] => 2026-06-24 22:08:28 [post_modified_gmt] => 2026-06-24 22:08:28 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=19972 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [4] => WP_Post Object ( [ID] => 19827 [post_author] => 1 [post_date] => 2026-06-05 15:15:01 [post_date_gmt] => 2026-06-05 15:15:01 [post_content] => Welcome to our “A Day in the Life” blog series, where we highlight the expertise and experiences of our team members as they work to advance Princeton Hydro’s mission of improving ecosystems, quality of life, and communities. In this edition, we take to the skies with Ryan Eno, EIT, a Staff Engineer in our Geosciences group and an FAA-certified drone operator whose work blends engineering, technology, and creativity to support our projects. Ryan’s role offers a unique perspective (quite literally) on how drones are shaping environmental restoration and monitoring efforts. Let’s get a bird’s-eye view of a day in the life of a Princeton Hydro drone operator: Pre-Flight Planning and Airspace Navigation Ryan’s day often starts well before he steps onto a project site. Drone operation requires careful pre-flight planning, especially when working across varied landscapes and within regulated airspace. Ryan uses mapping tools and satellite imagery to identify safe launch points and ensure he can maintain a clear line of sight with the drone throughout the flight, a requirement set by the FAA. “For any project, the first step is checking airspace restrictions,” Ryan explains. “There are limitations around government facilities, state lands, and, without much advanced notice, no-fly zones that can be implemented around high-profile locations.” Operating drones professionally comes with even more regulatory and logistical considerations. “There are a lot of airspace restrictions to keep track of,” Ryan explains. “For example, drones cannot be flown in New Jersey State Parks without permission, and temporary flight restrictions can change depending on circumstances.” Balancing these requirements with field conditions requires flexibility, attention to detail, and constant awareness. “It is all about planning, safety, and making sure we are operating responsibly and within the law.” [gallery ids="19895,19896,19897"] In the Field: Navigating Conditions and Capturing the Shot Once on site, Ryan is focused on safety, positioning, and capturing the right visuals. “In many cases, just getting the drone to a safe takeoff location is the first challenge,” he says. “You need a clear opening in the tree canopy and enough space to launch and land safely.” Operating in natural environments introduces additional complexity. Dense vegetation, uneven terrain, and changing weather conditions require constant awareness and adaptability. “Even though our drone has obstacle-avoidance sensors, they are not perfect, especially with moving tree branches,” Ryan notes. “I have to stay focused and anticipate how the drone will move through the environment.” Ryan also remains mindful of wildlife and ecological sensitivity during drone operation, “Drones usually fly high enough as to not disturb animals on the ground, but we always pay close attention to birds, especially during nesting seasons." [gallery ids="19884,19882,19883"] Capturing Change from Above One of the most valuable aspects of Ryan’s work is documenting the transformation of our project sites. Using Princeton Hydro’s DJI Phantom 4 Pro V2, a high-resolution aerial photography drone, Ryan captures imagery that helps tell the story of a project from start to finish. “I really enjoy projects where I can capture a site before and after construction,” he says. “The drone really helps tell the story and provide a complete perspective. It captures the entire transformation in a single frame, which is much harder to convey from the ground.” The aerial drone images and videos are often used to:
We're pleased to share the following article, originally written by Sean Leslie, Senior Manager of Content and Marketing at Cultivo, and republished with permission. Princeton Hydro and Cultivo recently collaborated in Southwest Montana to assess vegetation, wildlife, and other indicators of ecosystem health as part of a broader biodiversity monitoring initiative for a grassland restoration project. The blog offers an inside look at the monitoring methods used to establish a biodiversity baseline, highlights several unique species encountered during fieldwork, and examines the role of biodiversity and collaborative monitoring in supporting resilient landscapes and successful conservation outcomes.
When we think about nature-based solutions, carbon sequestration often steals the spotlight. But carbon is only one part of a much larger story.
At Cultivo, we believe that restoring grasslands goes far beyond storing carbon underground; it’s about rebuilding complete, living ecosystems. True regenerative progress is measured in on-the-ground ecological health, and one vital metric of that health is biodiversity. Ecosystems rich in plant, bird, and insect life are proven to be more productive, more resilient, and better equipped to thrive.
And just as we do when measuring and verifying sequestered carbon, to ensure our projects deliver measurable, lasting benefits in terms of biodiversity, we’re not relying on satellite images or computer models; we’re putting boots on the ground.
Case in point: Cultivo’s Ecological Impact Senior Manager, Emiline Koopman, recently completed an intensive field visit to one of our partner sites in beautiful Southwest Montana. Alongside the expert field team at Princeton Hydro, she implemented our Biodiversity and Ecosystem Services (BES) monitoring framework across the landscape.
Virtual meetings and digital mapping are great for planning, but nothing replaces walking the land. And during the early summer pilot sampling campaign, Cultivo and Princeton Hydro did exactly that, deploying a full suite of monitoring techniques:
To monitor avian diversity, small weatherproof audio recording devices called Acoustic Recording Units (ARUs) are placed across the property to capture the natural soundscape – including bird calls – continuously over the summer breeding season. At the same time, ornithologists perform human “point counts” by standing quietly in one place for set time intervals with binoculars and clipboards to visually and auditorily record every species seen or heard. Together, these techniques provide a picture of species presence, relative abundance, and spatial distribution, acting as an indicator of overall habitat health.
Measuring plant health and structure, requires laying long measuring tapes across the ground through a specific habitat type and placing square frames (quadrats) at fixed increments along the line. Along this path, researchers systematically count live and dead woody plant stems, measure canopy gaps, and catalog every plant species inside the quadrats, providing detailed ground-level data on plant species richness, ground cover, and pasture resilience.
Insect populations are tracked and measured with Malaise traps, which resemble small, open-sided mesh tents with a collection jar at the top. Flying insects naturally bump into the traps’ fabric walls, fly upward, and are gathered for identification using conventional and eDNA metabarcoding techniques. To complement this, researchers also sit quietly near blooming native plants for timed intervals to perform insect flower visitation counts, tracking specific pollinators including bees, ants, and wasps.
One of the greatest rewards of field work is seeing firsthand what we are working so hard to protect. In Southern Montana, the team encountered an incredible array of flora and fauna.
Here are a few of the standout species that call this ecosystem home, with pictures taken during the recent field visit:
On the high-elevation rangelands of Southwestern Montana, small native plants punch well above their weight. Among them, Spearleaf stonecrop (Sedum lanceolatum) is a tough, fleshy succulent that thrives in the rocky soils of our intermontane sagebrush valleys.
It also happens to be the exclusive host plant for the Rocky Mountain parnassian (Parnassius smintheus), a high-altitude cousin in the swallowtail family. Female parnassians lay their eggs right next to stonecrop patches so hungry spring caterpillars can feed on the leaves. As they eat, the larvae absorb bitter chemicals from the plant, making both the caterpillars and the red-spotted adult butterflies completely unpalatable to birds, a classic example of the invisible, delicate connections that make these high-desert ecosystems work.
If any bird defines the vast sagebrush country of Southwestern Montana, it’s the Brewer’s sparrow (Spizella breweri). This small, inconspicuously plumaged songbird is intricately tied to healthy, intact rangelands.
Brewer’s sparrows are sagebrush obligates, meaning they rely almost entirely on big sagebrush ecosystems for nesting, shelter, and feeding on insects and seeds. Their dull, streaked feathers provide perfect camouflage against native shrub leaves, while their long, breathy, trilling songs are a signature sound of spring on the range. Because they depend so heavily on large, unfragmented landscapes, healthy populations of Brewer’s sparrows are a key indicator of a thriving, well-managed rangeland ecosystem.
Where short prairie grasses like blue grama and buffalo grass break up the sagebrush valley, you’ll find the thick-billed longspur (Rhynchophanes mccowni). This species relies heavily on grazing to keep vegetation low; without livestock or bison disturbing the grass, their nesting habitat disappears.
On their breeding grounds, they feed heavily on protein-rich grasshoppers. During springtime, males perform incredible aerial courtship displays: They fly up to 30 feet in the air and "parachute" back down on outstretched wings with their white tail feathers spread wide, singing a warbling song to impress females and mark their territory.
Pronghorn (Antilocapra americana) are gorgeous, iconic fixtures of Southwestern Montana's open valleys. While commonly referred to as "pronghorn antelope," they aren't true antelopes at all; their closest living relatives are actually the African giraffes and okapis.
Built purely for acceleration and endurance, pronghorn are the fastest land mammals in the Western Hemisphere, topping out at speeds over 55mph, with this extreme speed attributed to a prehistoric evolutionary "arms race" with the now-extinct American cheetah (Miracinonyx). While modern wolves and coyotes can't come close to matching a pronghorn's pace today, these remarkable animals retain their incredible speed and massive heart-and-lung capacity, allowing them to cruise effortlessly across open rangelands.
Small, long-legged, and undeniably cute, the burrowing owl (Athene cunicularia) is one of the range's most charismatic residents. Unlike most owls, these birds are diurnal, meaning they are active during the day and can often be spotted standing guard on fence posts or mounds.
Burrowing owls have a fascinating relationship with prairie dogs and other underground mammals; because the owls can't dig their own homes, they rely entirely on abandoned burrows for nesting and shelter. These opportunistic hunters eat a wide-ranging diet that includes insects, small mammals, lizards, snakes, and birds. Highly sensitive to habitat loss, their presence is a great sign of an intact, biodiverse grassland.
Ranching landscapes are complex, working environments. During the visit, the team noted that this ecosystem is facing real-world challenges, including severe ongoing regional drought and water access issues. This is where our work regenerating the landscape becomes crucial; by combining rotational grazing strategies with targeted infrastructure improvements, we can significantly boost soil health, turning vulnerable land into a thriving, resilient ecosystem.
According to the Natural Resources Conservation Service (NRCS), every 1% increase in soil organic matter lets an acre of land hold roughly 20,000 gallons of extra water. That moisture doesn't just keep pastures green longer during a dry spell, it also helps safeguard the land against wildfires. As research from the USDA and fire ecology experts shows, soils rich in organic matter maintain higher plant moisture levels and soil humidity, creating a natural firebreak that slows down fire spread and helps landscapes bounce back faster if a burn does occur.
Hand-in-hand with our landscape restoration work, the ranch is actively participating in a broader ecological monitoring network, with ongoing research from local university programs and regional partnerships. Cultivo is actively working to coordinate with these existing initiatives, synthesizing data and supporting local land stewards.
By pairing high-tech monitoring tools, on-the-ground data collection, and deep, generational knowledge of local ranchers, we can build restoration strategies that support both wildlife and agricultural livelihoods.
Implementing our Biodiversity and Ecosystem Services framework in Montana reminds us exactly why we do this work: to accelerate investment into nature and regenerate the world’s land into healthy, resilient ecosystems.
As we refine our field protocols and analyze the baseline data gathered in Montana, we move one step closer to scaling transparent, high-integrity nature restoration worldwide.
Stay tuned for more field updates as we continue monitoring biodiversity across our global project portfolio! Big thanks to Princeton Hydro's Mike McGraw, CSE, QAWB, ACE, Tanya Dapkey, CE, and Eric Zawatski, CWB, for providing photos and information for the species listed in this post!
New Jersey Governor Mikie Sherrill signed Bill S3403/A4007 into law, requiring sellers to disclose the presence of dams on properties being sold in New Jersey along with information regarding the dams' condition, inspection history, hazard classification, and ownership obligations. The law is intended to improve transparency during real estate transactions and help buyers better understand the responsibilities that can accompany dam ownership before becoming contractually obligated to buy the property.
For many, a waterbody can be an attractive property asset that enhances aesthetics, recreation opportunities, and property value. However, what is not always apparent is that the waterbody may be maintained by a dam, and ownership of that dam comes with legal, financial, and regulatory responsibilities. Because dams are regulated infrastructure, depending on their size and hazard classification, owners may be responsible for routine inspections, maintenance, repairs, emergency planning, and ongoing compliance with state regulations. In some cases, property owners do not discover the full extent of those obligations until after a real estate transaction is complete, resulting in unexpected costs and liabilities.
"Dams are critical infrastructure, but they also have long-term responsibilities. Owners can face substantial costs associated with inspections, maintenance, rehabilitation, and regulatory compliance, and those obligations often transfer with the property purchase," explained Geoffrey M. Goll, PE, President of Princeton Hydro and NJ-licensed Professional Engineer. "This legislation helps ensure that prospective buyers understand the presence and condition of a dam so that they can evaluate those obligations upfront. Families and business owners can make informed investments while preventing unexpected liabilities, promoting public safety, and encouraging responsible stewardship of aging dam infrastructure across the state."
The passage of S3403/A4007 follows months of advocacy led by The Nature Conservancy in New Jersey, which first proposed the legislation and worked closely with lawmakers, stakeholders, and bipartisan supporters throughout the legislative process. Through testimony, coalition building, and sustained engagement, the organization helped elevate awareness of the challenges and costs associated with dam ownership and the importance of providing prospective property buyers with clear and timely information.
"No family should learn after purchasing a home that they have also assumed responsibility for a structure that could require extensive repairs or ongoing compliance costs," said Rebecca Hilbert, New Jersey Policy Associate at The Nature Conservancy. "By requiring transparency for buyers upfront, this legislation supports consumers, enhances public safety and helps ensure that dams affecting New Jersey's rivers and communities are responsibly managed."
Section 1 of the New Jersey Dam Disclosure Law states, "A seller of real property located in this State shall disclose, on the property condition disclosure statement, whether a dam is located within the boundaries of the property and any actual knowledge of the seller concerning the dam, as required pursuant to this section, to the purchaser before the purchaser becomes obligated under any contract for the purchase of the property." The law also adds specific dam-related questions to the property condition disclosure statement, including:
Additionally, the law directs prospective buyers to New Jersey Department of Environmental Protection (NJDEP) resources regarding dam ownership responsibilities, dam removal, and hazard classifications to gain a better understanding of the implications of dam ownership before becoming contractually obligated or completing the sale transaction.
The law serves a broader public safety purpose. Better informed ownership can encourage compliance with dam safety requirements, timely maintenance and repairs, and informed decision-making regarding rehabilitation, dam removal, and river restoration.
These responsibilities are not insignificant. Under New Jersey's Safe Dam Act and Dam Safety Standards (N.J.A.C. 7:20), regulated dams must be inspected by a qualified New Jersey-licensed Professional Engineer every two to four years, depending on the dam's hazard classification. Regulated dam owners are also required to maintain an Operation and Maintenance Manual, while Hazard Class I and II dams must have a NJDEP-approved Emergency Action Plan in place. A regulated dam is generally defined as an artificial dike, levee, or barrier that raises the waters of a stream more than five feet above the usual mean low water height. Many property owners may be unaware that these requirements apply to a structure on their property until they begin exploring its regulatory status or ownership obligations, or receive a compliance letter from NJDEP.
These requirements exist to protect people, property, and the environment from the consequences of dam failures. When dams are not properly maintained, the impacts can extend far beyond the property boundary, potentially resulting in downstream flooding, property damage, environmental degradation, impacts to wildlife habitat, and, in the most severe cases, loss of life. By increasing awareness of dam ownership responsibilities before a property changes hands, the new law can help support safer, more proactive management of New Jersey's aging dam infrastructure while reducing the likelihood of unexpected costs and obligations for future owners.
In a press release from The Nature Conservancy the organization stated, "The Nature Conservancy supported the legislation because dams can have lasting impacts on public safety, local communities and the health of New Jersey's waterways. Ensuring property owners understand their responsibilities is an important step toward informed stewardship of dams that affect both people and nature."
We applaud The Nature Conservancy for spearheading this effort and building the bipartisan support needed to move the legislation from concept to law. We also thank Governor Sherrill, Senator John Burzichelli, Assemblyman Dave Bailey, Assemblyman Sterley S. Stanley, and the many legislators who recognized the importance of greater transparency for New Jersey homebuyers and businesses.
Princeton Hydro has long supported proactive dam safety management, providing dam inspections, geotechnical investigations, regulatory guidance, rehabilitation planning, and dam removal services to property owners, municipalities, organizations, and regulatory stakeholders throughout New Jersey and beyond. For decades, Geoff has been a leading voice in dam safety and removal. Widely recognized for pioneering dam removal efforts in New Jersey and for his expertise throughout the United States and internationally, Geoff has spent more than thirty years evaluating dams and helping owners navigate complex regulatory and infrastructure challenges. To learn more about dam safety inspection, we invite you to read our recent blog, "A Day in the Life of a Dam Inspector: Casey Pantaleo, PE."
Volunteers and community stakeholders gathered at Cupsaw Lake in Ringwood Township, NJ for the installation of two floating wetland islands, an innovative nature-based solution that improves water quality while enhancing biodiversity.
The project was funded by Skylands Guardian, a nonprofit organization dedicated to protecting the natural resources of New Jersey's Highlands region through education, advocacy, and environmental stewardship. In partnership with Skylands Guardian, Princeton Hydro Aquatic Ecologist Katie Walston-Frederick led the hands-on installation event, which transformed native plants and recycled materials into living ecosystems designed to benefit the lake for years to come.
Nestled within the Ramapo Mountains, Cupsaw Lake is a 65-acre freshwater lake in the heart of Ringwood Township. To help preserve its long-term ecological health, local partners continue to invest in innovative, science-based management initiatives. Floating wetland islands are one such solution.
Constructed from recycled materials and planted with native vegetation, floating wetland islands are designed to mimic the functions of natural wetlands. Beneath the surface, extensive root systems create habitat for beneficial microbes that help remove excess nutrients from the water column while providing shelter and foraging opportunities for fish and other wildlife. The result is a floating ecosystem that supports water quality, biodiversity, and habitat enhancement all at once.
Research has shown that a 250-square-foot floating wetland island can remove approximately 10 pounds of phosphorus annually while providing roughly the same nutrient-processing surface area as one acre of natural wetland. Considering that a single pound of phosphorus can generate up to 1,100 pounds of wet algal biomass, floating wetland islands have the potential to significantly reduce nutrient availability and help limit some of the factors that contribute to nuisance algal blooms.
A key component of the Cupsaw Lake project was community participation.
Katie coordinated and directed the installation effort, guiding volunteers through each stage of the process. Participants learned how to prepare native plants, install plant plugs within the floating island matrix, apply protective goose netting, and properly deploy and anchor the islands within the lake. The event provided an opportunity for volunteers to learn firsthand about lake ecology, nutrient management, and the role innovative restoration tools can play in protecting local water resources.
As the newly planted vegetation establishes itself in the coming months, the islands will become increasingly effective at nutrient uptake while creating a visually appealing focal point within the lake. Over time, the native plantings and submerged root systems will provide valuable habitat for fish, macroinvertebrates, and other wildlife. In addition to their environmental benefits, the islands will serve as a visible reminder of the community's commitment to protecting and enhancing Cupsaw Lake.
The project also aligns with broader watershed management efforts taking place throughout Ringwood and the New Jersey Highlands. In 2019, the Borough of Ringwood became the first municipality in New Jersey to pursue a regional approach to private lake management through a public-private partnership with four lake associations: Cupsaw, Erskine, Skyline, and Riconda.
Situated within the northeast corner of the Highlands region, Ringwood is home to numerous lakes and reservoirs that provide drinking water to millions of New Jersey residents. To support the long-term protection of these resources, the Borough partnered with Princeton Hydro to develop a comprehensive watershed management plan that identifies and prioritizes projects that address both immediate and future water quality concerns.
This approach recognizes that healthy lakes require more than in-lake management. Sustainable improvements depend on addressing nutrient and sediment sources throughout the surrounding watershed. And, organizations like Skylands Guardian play a critical role in turning watershed planning into on-the-ground action. Projects like the Cupsaw Lake floating wetland islands complement larger watershed initiatives by improving water quality, enhancing habitat, and fostering community engagement.
During her more than 11 years with Princeton Hydro, Katie has contributed to a wide range of water quality monitoring programs, fisheries investigations, habitat restoration projects, and watershed assessments. She serves as the firm's primary coordinator for floating wetland island projects and has overseen installations at waterbodies throughout the Mid-Atlantic.
In 2017, she became certified as an Island Master Builder through Floating Island International, receiving specialized training in the design, construction, installation, and application of floating wetland island technology. Her expertise helped ensure that the Cupsaw Lake installation project not only achieved its technical objectives but also provided a meaningful educational experience for volunteers and community members.
To learn more about another one of Princeton Hydro's long-term lake management initiative, explore our blog, Two Decades of Lake Management Innovation at Duke Farms, which highlights efforts to protect and monitor the interconnected lakes and ponds across Duke Farms' 2,700-acre property in Hillsborough, New Jersey.
When a dam is removed, what happens to all the sediment that has built up behind it?
That question was the focus of a recent Dam Busters webinar led by Geoffrey M. Goll, PE, President of Princeton Hydro and an internationally recognized expert in dam removal and river restoration.
During the session, Geoff shared insights on how sediment behaves during dam removal projects, how it accumulates behind dams, and how different materials such as sand, silt, and organic matter respond once the dam is removed. He also discussed the methods practitioners use to estimate how much sediment is likely to move, how quickly it will travel, and the risks it may pose downstream, along with the practical decisions project teams face, including when to rely on natural processes, when intervention is needed, and how to design a strategy that balances ecological benefits, cost, and potential impacts.
During the webinar, Geoff highlighted a real-world example of a dam removal project that required careful sediment management: the Paulina Lake Dam removal on the Paulins Kill River in New Jersey. For this project, the team implemented a phased dam breach, gradually lowering water levels to control the release of sediment and allow the river to begin forming its new channel. A portion of the sediment, particularly the highly organic material near the dam, was actively removed to prevent downstream impacts, while the rest was allowed to mobilize naturally.
To learn more about the Paulina Lake Dam removal project and see the transformation in action, click here to read our blog.
Dam Busters is an initiative created by the Mass Rivers Alliance in partnership with the Massachusetts Division of Ecological Restoration and the Charles River Watershed Association. Its mission is to provide dam removal stakeholders with the knowledge and tools needed to successfully support and implement projects.
The program offers expert-led webinars with live Q&A, technical resources and guidance, site visits and hands-on learning opportunities, and in-person workshops and conferences. Whether new to dam removal or actively working in the field, Dam Busters provides valuable, expert-driven insights to help guide dam removal efforts.
Geoffrey M. Goll, PE, a founding partner and the President of Princeton Hydro, has over 35 years of experience in water resources engineering, geotechnical engineering, and river restoration. He is widely recognized for advancing innovative and effective approaches to river restoration.
Geoff holds a B.S. in Civil Engineering from Rutgers University, a Master of Engineering Management from the University of Wisconsin–Madison, and is a licensed Professional Engineer in 11 states. He pioneered dam removals for the purposes of fish passage in New Jersey and has overseen more than 50 dam removal designs. His understanding of sedimentation mechanisms and management of sediment behind impoundments has been instrumental in managing the mitigation of environmental impacts during and after demolition of river and stream obstructions. Click here to learn more about Geoff.
Welcome to our “A Day in the Life” blog series, where we highlight the expertise and experiences of our team members as they work to advance Princeton Hydro’s mission of improving ecosystems, quality of life, and communities. In this edition, we take to the skies with Ryan Eno, EIT, a Staff Engineer in our Geosciences group and an FAA-certified drone operator whose work blends engineering, technology, and creativity to support our projects.
Ryan’s role offers a unique perspective (quite literally) on how drones are shaping environmental restoration and monitoring efforts. Let’s get a bird’s-eye view of a day in the life of a Princeton Hydro drone operator:
Ryan’s day often starts well before he steps onto a project site. Drone operation requires careful pre-flight planning, especially when working across varied landscapes and within regulated airspace. Ryan uses mapping tools and satellite imagery to identify safe launch points and ensure he can maintain a clear line of sight with the drone throughout the flight, a requirement set by the FAA. “For any project, the first step is checking airspace restrictions,” Ryan explains. “There are limitations around government facilities, state lands, and, without much advanced notice, no-fly zones that can be implemented around high-profile locations.”
Operating drones professionally comes with even more regulatory and logistical considerations. “There are a lot of airspace restrictions to keep track of,” Ryan explains. “For example, drones cannot be flown in New Jersey State Parks without permission, and temporary flight restrictions can change depending on circumstances.” Balancing these requirements with field conditions requires flexibility, attention to detail, and constant awareness. “It is all about planning, safety, and making sure we are operating responsibly and within the law.”
Once on site, Ryan is focused on safety, positioning, and capturing the right visuals. “In many cases, just getting the drone to a safe takeoff location is the first challenge,” he says. “You need a clear opening in the tree canopy and enough space to launch and land safely.”
Operating in natural environments introduces additional complexity. Dense vegetation, uneven terrain, and changing weather conditions require constant awareness and adaptability. “Even though our drone has obstacle-avoidance sensors, they are not perfect, especially with moving tree branches,” Ryan notes. “I have to stay focused and anticipate how the drone will move through the environment.”
Ryan also remains mindful of wildlife and ecological sensitivity during drone operation, “Drones usually fly high enough as to not disturb animals on the ground, but we always pay close attention to birds, especially during nesting seasons."
One of the most valuable aspects of Ryan’s work is documenting the transformation of our project sites. Using Princeton Hydro’s DJI Phantom 4 Pro V2, a high-resolution aerial photography drone, Ryan captures imagery that helps tell the story of a project from start to finish. “I really enjoy projects where I can capture a site before and after construction,” he says. “The drone really helps tell the story and provide a complete perspective. It captures the entire transformation in a single frame, which is much harder to convey from the ground.”
The aerial drone images and videos are often used to:
This type of imagery is especially powerful for Princeton Hydro’s ecosystem restoration projects. A recent example is Princeton Hydro’s work on the Paulina Lake Dam removal and Paulins Kill River restoration in Warren County, New Jersey. Led by The Nature Conservancy and funded by the NJDEP Division of Fish and Wildlife, the project reconnected 7.6 miles of river habitat, building on an additional 10 miles restored through the earlier Columbia Lake Dam removal. From the ground, it can be challenging to grasp the full extent of change following a dam removal. Aerial imagery captured before, during, and after construction provides a comprehensive view of how the river system responds. When the site was revisited a year later, the transformation was clear. The river had re-established its natural flow and reconnected habitats that had been fragmented for generations.
Drone footage captured by The Nature Conservancy, Renova Environmental Company, and Princeton Hydro played a key role in documenting this process. Drawing on aerial imagery collected before demolition and throughout construction, the resulting video illustrates the full progression of the project, from initial notching to full restoration. It highlights how careful sequencing, sediment management, and adaptive design allow rivers to recover rapidly once barriers are removed.
Drones at Princeton Hydro are used in a wide range of applications. “They allow us to access remote areas and collect data much faster than traditional methods,” Ryan says. “Applications like wildlife surveys and large-scale monitoring are being transformed by drone technology." Drones equipped with multispectral, thermal, and LiDAR sensors can generate detailed datasets that support habitat mapping, vegetation analysis, and long-term monitoring. These tools help project teams better understand site conditions, identify degraded areas, measure restoration success over time, and conduct comprehensive scientific studies.
A notable example is Princeton Hydro’s involvement in a groundbreaking drone-based research initiative to monitor harmful algal blooms (HABs) in the Delaware River Watershed. This effort, done in partnership with Friends of Hopewell Valley Open Space with funding from the National Fish and Wildlife Foundation's (NFWF) Delaware Watershed Conservation Fund (DWCF), in partnership with the U.S. Fish & Wildlife Service, the project leverages drone technology and advanced data modeling to identify environmental conditions that contribute to HAB formation and aims to develop tools and methodologies for early detection and management.
Drones equipped with multispectral imaging systems capture high-resolution spatial data that is then integrated with digital platforms to link remote-sensing with the drone data and on-the-water collected data. The field-based water quality measurements are being collected by a team of trained community volunteers who are using phycocyanin fluorometer meters to measure concentrations of the photosynthetic pigment phycocyanin, which is produced primarily by cyanobacteria. Volunteers enter the data into a customized ArcGIS mobile-friendly survey. These combined datasets will be used to develop and validate predictive algorithms for both planktonic and benthic HABs under varying seasonal and hydrologic conditions. Drone flights and data collection began in Fall 2025 and will continue through 2026, with a final report anticipated in 2027. Click here to read more about this initiative.
Ryan is a Staff Engineer who provides services in geotechnical engineering, CAD drafting, and drone imagery. He supports a wide range of projects, contributing to foundation design, embankment stability and settlement modeling, report preparation, and laboratory soil testing.
Ryan earned his Bachelor of Science in Civil Engineering from Rowan University in 2022 and joined Princeton Hydro in April 2023. His interest in engineering began in high school through participation in a STEM club, where he developed a passion for creative problem-solving and infrastructure design.
His introduction to drone operation came early in his career when he was given the opportunity to become licensed. After earning his FAA Part 107 certification in June 2022, he began integrating drone technology into engineering and environmental applications. Today, Ryan uses drones to support aerial imagery, project documentation, and marketing efforts, adding an important visual dimension to Princeton Hydro’s work. He continues to stay current with evolving technologies and applications by following industry developments and engaging with professional networks.
We hope you enjoyed this latest edition of our "Day in the Life" blog series. Click here to read the previous edition, which follows Casey Pantaleo, PE, a licensed Professional Engineer and Senior Project Manager on the Engineering Services team, as he performs one of his highly specialized roles: dam inspection. And, stay tuned for more behind-the-scenes stories from our talented team!
Conservation professionals, land stewards, and researchers from across New Jersey gathered for the New Jersey Invasive Species Strike Team Conference, the most comprehensive statewide forum dedicated to invasive species management. The conference was presented by Friends of Hopewell Valley Open Space (FoHVOS), an accredited nonprofit land trust committed to land protection, resource conservation, and community engagement.
The conference was held at the Boathouse at Mercer Lake, which provided an ideal backdrop for a day focused on protecting New Jersey’s natural landscapes. The conference, which Princeton Hydro was proud to sponsor, included exhibitor tables, networking opportunities, and a variety of presentations. The day kicked off with welcome remarks from Jenn Rogers, Executive Director of FoHVOS, and representatives from Mercer County Parks. Educational sessions throughout the day explored the dynamic and evolving challenges facing New Jersey’s ecosystems, cutting-edge academic research, and practical, field-based solutions for mitigating invasive species:
Native to the Yangtze and Amur River basins in China, the silty pond mussel (Sinanodonta woodiana) is a highly invasive freshwater species that has spread worldwide, often without detection. Its life cycle makes early identification especially difficult: microscopic larvae, known as glochidia, attach to the gills of host fish, allowing the mussel to move unnoticed through connected waterways and establish new populations far from their point of origin.
This stealthy mode of transport is believed to be how the silty pond mussel arrived in the United States. The species was first documented in 2010, when it was discovered in New Jersey Conservation Foundation’s Wickecheoke Creek Preserve, which previously operated as a fish farm and is now protected land. Although the mussel had likely been present for several years, its absence from North American records meant it went undetected until genetic confirmation was completed. Investigations identified invasive bighead carp imported for aquaculture as the most likely pathway of introduction.
The discovery raised immediate concern because of the preserve’s ecological significance. Located in Hunterdon County, the Preserve supports nearly 400 native plant species and 14 miles of high‑quality streams. It sits at the headwaters of Wickecheoke Creek, a tributary of the Delaware River that connects to the Delaware and Raritan Canal, part of a drinking water system serving approximately one million New Jersey residents.
Once established, silty pond mussels can overwhelm aquatic ecosystems. During the presentation, Scott Churm and Dr. Emile DeVito explained that invasive mussels may account for over 75% of total benthic biomass in affected waterbodies. Such dominance can disrupt food webs by outcompeting native mussels; harm fish when larvae attach to their gills, sometimes triggering fatal biological responses; reduce biodiversity; and alter water chemistry, ultimately degrading habitat quality for both plants and animals.
Following the initial discovery of the silty pond mussel, testing conducted by the New Jersey Invasive Species Strike Team, the New Jersey Endangered and Nongame Species Program, and the North Carolina State Museum of Natural Sciences confirmed the presence of this invasive species. With confirmation in hand, early eradication efforts began, centered on careful detection and sustained monitoring to better understand the scope of the infestation.
To assess the extent of the mussel’s presence, response teams combined traditional field surveys with advanced scientific techniques. This integrated approach included SCUBA and snorkel surveys, physical sampling of mussels and stream substrates, and environmental DNA (eDNA) testing, which detects trace genetic material released by organisms into the water and allows scientists to identify species that may not yet be visible during field inspections.
Together, these methods made it possible to find both established populations and early-stage infestations. In 2021, researchers applied highly sensitive genetic markers developed by Rutgers University to determine whether the silty pond mussel had escaped the former aquaculture ponds and spread into surrounding waterways. Initial eDNA sampling focused on Wickecheoke Creek Preserve, where testing provided a clearer picture of the species’ distribution and helped validate findings from visual surveys.
Monitoring efforts later expanded beyond the preserve. In 2021 and 2022, water samples collected from the Raritan River at the confluence of the Millstone and Raritan Rivers produced positive eDNA detections for silty pond mussel. These results pointed to the potential presence of a population within the Raritan River Watershed and highlighted the need for a rapid, coordinated response to prevent further spread.
Together, these methods made it possible to identify both established populations and early-stage infestations. Initial eDNA sampling focused on the preserve, where testing provided a clearer picture of the species’ distribution and helped confirm results from visual surveys. Based on those findings, monitoring efforts expanded to connected waterways where the researchers applied highly sensitive genetic markers developed by Rutgers University to determine whether the silty pond mussel had escaped the former aquaculture ponds and spread beyond Wickecheoke Creek Preserve. In 2021 and 2022, water samples collected from the Raritan River at the confluence of the Millstone and Raritan Rivers yielded positive eDNA detections for silty pond mussel. These results indicated the possible presence of a population within the Raritan River watershed and reinforced the need for a rapid, coordinated response to limit further spread.
Eradication efforts at Wickecheoke Creek Preserve began with extensive planning and regulatory review to ensure treatments would be both effective and protective of surrounding ecosystems. Before field work could proceed, the project team secured all required state permits, verified pond depth and water volume to calculate precise treatment dosages, posted public notices and signage throughout the site, and established protocols for daily safety briefings and site inspections. This preparation ensured the project was conducted safely, transparently, and in full compliance with permit requirements.
Following this approval phase, Princeton Hydro’s licensed applicators, working closely with SePRO and project partners, implemented a targeted treatment using Natrix®, an EPA-registered chelated copper pesticide formulated specifically for invasive mollusk control. Treatments were designed to maintain copper concentrations at 1 part per million for a minimum of 96 hours. To ensure consistent and accurate dosing, water samples were collected and analyzed twice daily at an onsite laboratory throughout the treatment period.
This work is part of an adaptive, science-driven eradication strategy that depends on clear roles and close collaboration among partners. The approach is both preventative and responsive, allowing the team to adjust tactics based on monitoring results and site conditions. The project is supported by funding from the U.S. Fish and Wildlife Service and the Delaware River Greenway Partnership through the Lower Delaware Wild and Scenic Program.
Looking ahead, the work at Wickecheoke Creek Preserve reflects the themes emphasized by Scott and Emile during their presentation: the importance of early detection, scientific innovation, and coordinated response in addressing invasive species. Continued collaboration among scientists, agencies, conservation organizations, and local communities strengthens the ability to respond quickly and adaptively, while education and public awareness support long-term prevention. Together, these efforts contribute to the protection of native species and freshwater systems and support the ongoing stewardship of our natural spaces.
Duke Farms, a Center of the Doris Duke Foundation, is a 2,700-acre landscape in Hillsborough, NJ, dedicated to restoring ecosystems, demonstrating sustainable land management, and inspiring environmental leadership. Once the privately-owned estate of J.B. and Doris Duke, the property now welcomes more than 150,000 visitors annually who come to experience its diverse habitats, miles of public trails, and innovative conservation programs.
Situated within the Raritan River Watershed and bordered by a mosaic of rural and suburban development, Duke Farms functions as a living laboratory for nature-based solutions in complex, fragmented landscapes. Its forests, meadows, waterways, and working lands offer an unparalleled setting to advance climate-positive strategies, including restorative land management and decarbonization initiatives, while maintaining an unwavering commitment to protecting wildlife and enriching biodiversity.
For more than 20 years, Princeton Hydro has partnered with Duke Farms to restore, monitor, and manage its interconnected lakes and ponds. In 2001, we developed a comprehensive Lake Management Plan to address water quality challenges, promote ecological balance, and ensure these systems could support both wildlife and public use. Since then, we have provided ongoing updates to align management strategies with the ecological objectives of the Duke Farms Foundation. Over time, the Foundation has expanded public access for education and recreation, highlighting the distinctions between shallow, artificial impoundments and natural lakes while implementing innovative, nature-based techniques for algae and aquatic plant control. Today, Duke Farms’ 11 lakes and ponds, eight of which were included in the original plan, remain central to the property’s water resources and continue to play a vital role in overall ecological health, stewardship programming, and public recreation opportunities.
Great Falls Cove at Duke Farms. Photo by Princeton Hydro Aquatic Ecologist Katie Walston-Frederick.
The original Lake Management Plan integrated routine water quality monitoring, hydrologic and pollutant-load modeling, adaptive aquatic plant management, and targeted interventions to restore ecological balance. Key components included invasive species control, such as Common Carp removal to support native fish populations, and a comprehensive algae and aquatic plant program that included aeration and aquascaping. This multifaceted approach established the foundation for long-term recovery across the lake system.
As Duke Farms expanded public access and strengthened its educational mission, management strategies evolved to emphasize innovative, low-impact techniques for shallow, human-made impoundments. Recent advancements implemented by Princeton Hydro include:
The most recent plan update incorporates techniques that were unavailable when the original plan was developed:
In 2012, Princeton Hydro conducted a detailed hydrologic analysis of Duke Farms’ interconnected lake system to evaluate water management strategies. Historically, water from the Raritan River was pumped into the lakes to maintain water levels. While reliable, this practice introduced elevated nutrients and sediments in the property’s lakes and ponds, degrading water quality and fueling nuisance algal blooms.
The study synthesized pump and discharge records, long-term climate and hydrologic data, and monthly water budgets, and included experimental pumping scenarios to assess alternatives. Results were transformative: under normal conditions, supplemental pumping could be reduced by more than 95%, and even during drought, by about 70%, without compromising lake levels. Based on these findings, Duke Farms adopted a low-volume, seasonal pumping strategy and transitioned to a higher-quality groundwater source, which significantly reduced nutrient loading, improved water clarity, and lowered energy consumption.
Ongoing monitoring remains a cornerstone of the Duke Farms–Princeton Hydro partnership. For each waterbody, the team conducts in-situ data collection, laboratory analyses, visual and observational evaluations, and detailed reporting. Data from continuous monitoring demonstrates sustained improvements in dissolved oxygen, water quality, and overall lake/pond health. This continuous feedback loop informs adaptive management decisions and allows Duke Farms to measure the ecological success of its restoration efforts.
We are proud to partner with Duke Farms in advancing the health and resilience of its water resources, a commitment that not only protects the lakes and ponds on the property but also delivers positive ecological benefits throughout the Raritan River watershed. Click here to learn more about our lake management work in the region. To explore Duke Farms, plan a visit to its beautiful property, sign up for educational programs, or discover ways to get involved in its conservation initiatives, visit Duke Farms’ website.
This summer, Princeton Hydro aquatic scientists joined forces with Billion Oyster Project and AKRF on an exciting effort to better understand how restored oyster reefs are supporting life in New York City’s waterways. The project, “Monitoring of Mobile Estuarine Organisms at Restored Oyster Reefs,” focuses on tracking fish, crabs, snails, and other aquatic species that call these reefs home, as well as using cutting-edge environmental DNA (eDNA) techniques to detect organisms that might otherwise go unnoticed.
As a consultant to AKRF, our team deployed collection gear across current and potential restoration sites, including Brooklyn Bridge Park, Bush Terminal Park, Flushing Bay, and Paedergat Basin. The sampling enclosures, left in the water for 48 hours, revealed a fascinating snapshot of estuarine life, from small schooling fish to a surprise dogfish, a small shark-like species that was one of the highlights of the summer survey sessions.
This collaborative initiative brings together multiple partners: Billion Oyster Project, the driving force behind large-scale oyster reef restoration in New York Harbor, is leading the project. AKRF, headquartered in New York City, is serving as the primary consultant; Princeton Hydro is leading the mobile estuarine sampling efforts and eDNA sample collection; and Monmouth University is analyzing the eDNA samples to help identify species present at the restoration sites.
Oyster reefs are living structures that provide essential habitat for a wide array of species, improve water quality through natural filtration capabilities, and enhance the resilience of New York Harbor against coastal storms and erosion. Monitoring oyster reefs ensures that restoration efforts are successful and helps scientists refine approaches for scaling up oyster reef projects in urban estuaries locally and throughout the world.
As the field sampling lead, Princeton Hydro completed two monitoring and sampling collection events, one this Spring and one this Summer, at the various oyster reef restoration sites. Using sea bass and minnow collection gear, our team - Jesse Smith, Aquatic Ecologist; Jackson Tilves, Staff Scientist; and Kaitlyn Jones, Staff Scientist - identified, measured, and documented each of the found species before safely returning them to the water. In addition, we collected in-situ water quality data at each site to help interpret how environmental conditions influence reef communities.
Our team brings deep experience and specialized equipment to this project. Princeton Hydro’s biologists have conducted estuarine surveys throughout the Hudson River and New York Harbor, led nekton and benthic sampling along New Jersey’s coastline, and carried out numerous studies that inform restoration and resilience efforts across the region.
Alongside traditional monitoring, the “Monitoring of Mobile Estuarine Organisms at Restored Oyster Reefs” project uniquely incorporates eDNA sampling. eDNA is genetic material that organisms shed into their surrounding environment, through skin cells, mucus, or waste, that can be detected in water samples. By collecting and analyzing eDNA, scientists can identify the presence of species that may not appear in sampling enclosures. The analysis provided by the team at Monmouth University helps paint a fuller picture of biodiversity at the restored oyster reef sampling locations.
The photos below capture moments from the field and the diverse aquatic life our team encountered, offering a glimpse into the many species that oyster reefs help support in the New York Harbor:
Founded in 2014, Billion Oyster Project is working to restore one billion oysters to New York Harbor while engaging New Yorkers directly in the process. Oyster reefs once covered hundreds of miles of shoreline, filtering water, creating habitat, and buffering against storm surge. Today, Billion Oyster Project’s mission is not only to restore these vital ecosystems but also to inspire lasting stewardship of them through educational programming and free STEM curricula for NYC schools and educators . To learn more about Billion Oyster Project and how to participate, click here.
Princeton Hydro is proud to partner with Billion Oyster Project, AKRF, and Monmouth University on this project and in the advancement of urban reef restoration. Together, we’re building knowledge that informs the future of oyster reefs in New York Harbor while strengthening ecological health and resilience of the city’s waterways for generations to come.
To learn more about our work to restore New York’s waterways, we invite you to read our Client Spotlight blog featuring Riverkeeper, a 501(c)3 nonprofit membership organization committed to protecting and restoring the Hudson River from source to sea and safeguarding drinking water supplies through advocacy rooted in community partnerships, science, and law.
When most people think of engineering, they picture bridges, buildings, and dams rising above the landscape. Yet the performance and longevity of these structures depend just as much on the subsurface conditions beneath them. Geotechnical engineering is the discipline dedicated to investigating, analyzing, and characterizing soil, rock, landscape, and groundwater conditions, and applying that data to the design and construction of safe, resilient, and sustainable infrastructure and restoration projects.
At Princeton Hydro, our geotechnical and soils engineers design and execute customized, cost-effective investigations that provide the parameters needed for successful design. Because geotechnical services touch every stage of a project, our integrated approach of investigation, including soils laboratory testing, analysis, and design, all done in-house, ensures streamlined communication, efficiency, and technical excellence.
This blog offers a closer look at what geotechnical engineering entails, the specialized capabilities Princeton Hydro provides, and real-world examples of how our work supports resilient, sustainable design.
Geotechnical Investigations: Our engineers can perform subsurface investigation, identification, and assessment of accumulated sediment, subsurface soils, and rock, as well as slope stability and stabilization modeling. Our work ranges from foundation type and bearing capacity assessments to mitigation strategies for unsuitable materials. We also regularly conduct forensic geotechnical investigations, which focus on investigating soil-interaction-related failures of engineered infrastructure.
Laboratory Testing: We operate an American Association of State Highway and Transportation Officials (AASHTO) Accredited laboratory in Sicklerville, NJ. This allows us to complete 100% of geotechnical investigation planning and oversight, laboratory testing, analysis, design, and reporting in-house. Our geotechnical laboratory performs a full suite of soils and materials testing, including grain size analysis, plasticity index, organic content, moisture content, compaction characteristics of soil (Standard and Modified Proctor), California bearing ratio (CBR), one dimensional consolidation, and flexible and rigid wall permeability testing under constant or falling head conditions. With this capability, we can rapidly deliver high-quality data to inform project design and construction. Our laboratory is also a U.S. Army Corps of Engineers (USACE) Validated Laboratory. Click here to view Princeton Hydro’s complete accreditation listing and certificate. And, click here to learn more about the USACE Materials Testing Laboratories and Validation.
Field & Construction Services: Our engineers are experienced in construction requirements, design, and methodology for various structures, as well as field inspections and special testing. We have a Certified Construction Specifier (CCS) on staff and ACI-certified concrete field-testing technicians. Our team performs compaction testing of soil and asphalt using a nuclear density gauge, reinforcing steel inspections, and 2006 International Building Code (IBC) special inspections. We help determine foundation type, site improvements, and optimal construction techniques.
Dredging & Sediment Investigations: Over our 25-year history, we’ve managed more than 100 dredging projects across freshwater and estuarine systems. We specialize in beneficial reuse of dredged material for ecological restoration, including wetland creation, thin-layer placement, and living shorelines. Our team provides sediment characterization, slope stability modeling, and contaminant analysis in complex, developed watersheds.
To bring this work to life, we’ve chosen a few Princeton Hydro projects that showcase where our geotechnical expertise helped solve unique challenges:
At Spring Creek Park North in Jamaica Bay, New York, decades of urbanization and dredged material placement had degraded more than 40 acres of tidal marsh and uplands. To address this, Princeton Hydro provided subsurface investigations and design services for a large-scale ecosystem restoration led by the USACE New York District, in partnership with NYC Parks.
A key design assumption was the reuse of excavated material: soils removed from wetland areas were repurposed to construct upland hills, supporting both ecological function and cost-effective implementation. Our work included geotechnical borings, slope stability analyses, and hydraulic modeling, as well as the collection of topographic and bathymetric survey data, wetland delineations, vegetation assessments, and hydrodynamic measurements. This data informed the development of slope stability and hydraulic models and guided the restoration design.
The project advanced through a structured engineering design process — with 30%, 60%, 90%, and 100% design submissions — along with preparation of technical specifications, permit applications, and a detailed construction cost estimate. When complete, the project will restore more than 43 acres of marsh and upland habitat, improving water quality, enhancing biodiversity, and strengthening climate resilience in one of New York City’s most ecologically significant coastal systems.
Princeton Hydro was contracted by USACE Philadelphia District to perform offshore subsurface geotechnical investigations in support of reconstructing the Indian River Inlet jetty at Delaware Seashore State Park. Working under challenging marine conditions, our team successfully advanced deep geotechnical borings (to depths of 100 feet) from a lift boat platform, collected soil samples, performed laboratory testing including triaxial strength, consolidation, and direct shear tests; and delivered detailed soil data. Despite difficult sea states, we maintained close communication with USACE to ensure safety and project continuity.
The resulting data provided USACE with critical insight into subsurface conditions, helping inform design alternatives for the new jetty structure.
At the Killcohook Confined Disposal Facility (CDF), Princeton Hydro carried out a large-scale subsurface investigation to support USACE Philadelphia District’s plans for raising the site’s perimeter dikes. The project site, formerly a National Wildlife Refuge, is located in Pennsville, New Jersey, on the eastern bank of the Delaware River, to the north of Fort Mott State Park and adjacent to the Supawna Meadows Wildlife Refuge. Each cell of the CDF receives dredge material from the Delaware River. The subsurface explorations performed by Princeton Hydro were conducted along the existing dike comprising the border of Cell 1 of the CDF. Cell 1 consists of an area of approximately 710 acres with the entire CDF covering 1,200 acres.
For this exploration project, Princeton Hydro was tasked with the performance of thirty-one (31) geotechnical borings as well as sixty-five (65) cone penetrometer tests with porewater measurements (CPTu) soundings. Princeton Hydro also provided site safety oversight in accordance with USACE standards. Soil samples were logged and collected by Princeton Hydro and tested at their Sicklerville, New Jersey geotechnical laboratory, which is accredited under the AASHTO Accreditation Program and validated by USACE for soils testing.
The data collected is now being used by USACE to design the upgraded dike system, ensuring safe, resilient operation of the facility for future dredged material management.
At the 545-acre Pedricktown North Confined Disposal Facility in Oldmans Township, New Jersey, located on the Delaware River west of Route 130 between Porcupine Road and Pennsgrove-Pedricktown Road, Princeton Hydro conducted a comprehensive subsurface investigation in support of a dike raising project led by the USACE Philadelphia District.
As part of this field exploration, our team performed eight geotechnical borings, thirty-eight cone penetrometer tests with porewater measurement (CPTu) soundings, and collected five grab samples. These efforts provided critical soil strength and settlement data to inform USACE’s design of the upgraded dike system.
In addition to managing subcontractors and ensuring compliance with USACE safety protocols, Princeton Hydro oversaw the field program, coordinated directly with the Project Manager, and delivered the final geotechnical report. This investigation is supplying USACE with essential geotechnical data to guide the design and construction of the improved dike infrastructure.
Coastal communities are on the frontlines of climate change, facing rising seas, stronger storms, and eroding shorelines. At the same time, these landscapes provide critical habitat and natural defenses that protect people, ecosystems and myriad wildlife. Coastal ecological restoration restores natural systems and strengthens future resilience to climate impacts.
Earlier this month, our team joined the New Jersey Coastal Resilience Collaborative (NJCRC) for its Coastal Ecological Restoration Technical Workshop, a full-day, in-person event held at the Rutgers EcoComplex in Bordentown, NJ. The workshop convened coastal stakeholders, researchers, practitioners, and managers to share knowledge and explore the latest science advancing coastal ecological restoration.
The day began with a work group session, “Advancing Science-Based Ecological Restoration Across New Jersey’s Coast,” led by a panel of experts and followed by an interactive Q&A. Click here to view the presentation. Participants then chose from a variety of technical sessions covering topics such as, eDNA and Water Quality as Indicators of Coastal Ecological Health; Smart Permitting for Restoration; and Diatoms as Ecological Indicators in Living Shoreline Applications.
Dana Patterson Grear, Princeton Hydro's Director of Marketing & Communications, delivered an engaging presentation titled, "How to Build a Digital Communications Toolkit for Climate Action." She provided practical guidance for turning communication into a powerful tool for advancing ecological restoration and climate resilience, including how to develop tailored climate messaging, understand the values of your audience and remove personal bias, and determine your level of engagement and capacity. Dana's presentation broke down complex communication strategies into actional steps that attendees can apply directly to their work. Click here to view her presentation slides.
Beyond the educational workshops, networking breaks, shared meals, and a post-workshop reception created opportunities to connect and collaborate. And, as a fun and fitting bonus, each participant went home with a complimentary native plant courtesy of Pinelands Nursery.
Coastal ecological restoration involves the rehabilitation and creation of coastal ecosystems, like wetlands, reefs, and shorelines, with the goal of restoring the natural processes and functions. These efforts provide long-term protection from erosion, create habitat for fish and wildlife, and build community resilience against flooding and storm surge.
At Princeton Hydro, we understand the impacts of climate change, including sea level rise, and use tools such as vulnerability assessments to inform our restoration designs. Our team specializes in designing and implementing living shorelines and habitat restoration projects. We combine field data, empirical approaches, ecological and geomorphic understanding, hydrologic and hydraulic modeling, and state-of-the-art computer programming technology to develop our designs. Our nature-based solutions deliver lasting ecological and community benefits.
A prime example of this work is the Spring Creek North Ecosystem Restoration project, located in Brooklyn and Queens, NY. Once part of the expansive Jamaica Bay wetland system, Spring Creek's salt marshes were heavily degraded over the last century. Princeton Hydro was contracted by the U.S. Army Corps of Engineers, New York District to lead the design and engineering for this restoration effort. Construction efforts began in early October 2025. Once completed, the project will restore approximately 43 acres of habitat within a 67-acre footprint, including low and high marsh, scrub shrub wetland, and maritime upland. Efforts also aim to improve water quality, increase biodiversity, and strengthen the overall Jamaica Bay ecosystem.
The following photos depict the degraded habitat and pre-construction conditions of the site. Stay tuned to our blog for more photos from each of the project phases.
We're pleased to announce the release of the "New Jersey Nature-Based Solutions: Planning, Implementation, and Monitoring Reference Guide," a free resource that provides a comprehensive roadmap to incorporating nature-based solutions (NBS) into infrastructure, construction, restoration, and resilience projects across the state.
Created by the Rutgers University New Jersey Climate Change Resource Center with support from The Nature Conservancy in New Jersey, the guide compiles current research, case studies, best practices, practical tools, science-based strategies, and funding resources to "inform and empower readers to implement and seek funding for NBS."
Click here to view and download the guide now.
As the guide states, "nature-based solutions (NBS) are defined as actions to protect, sustainably manage, and restore natural and modified ecosystems that address societal challenges effectively and adaptively, simultaneously benefiting people and nature." (IUCN 2024)
Whether you're a municipal planner, community leader, contractor, public- or private-sector professional, or an academic, new to NBS or experienced in large-scale restoration projects, the guide offers value at every level with practical instruction that spans the full project lifecycle, from planning and permitting to funding and long-term monitoring. While the content is tailored to New Jersey's diverse landscapes, the guide's insights and approaches are broadly applicable to regions with similar ecosystems, from Massachusetts to Virginia.
The guide also includes insights on how to address equity considerations and foster meaningful community engagement, helping users implement NBS that are both impactful and inclusive.
Princeton Hydro was proud to contribute technical expertise to this important effort. Our Director of Restoration & Resilience, Christiana L. Pollack, CERP, CFM, GISP, participated on the guide's steering committee, and our team provided informational resources, including content and case studies on invasive species management, wetland and floodplain enhancement, and dam and culvert removal to restore rivers and improve fish passage. These contributions along with those from many other participants, reflect the collaborative nature of the guide and the collective commitment to advancing NBS across the state.
The guide's easy-to-follow format includes four key sections:
Whether you're just beginning to conceptualize a project or deep into project implementation, this guide is an invaluable addition to your toolbox. We encourage you to explore, download, and share it widely! Click here to access the guide now.
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