We’re committed to improving our ecosystems, quality of life, and communities for the better.
Our passion and commitment to the integration of innovative science and engineering drive us to exceed on behalf of every client.
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[0] => WP_Post Object ( [ID] => 19607 [post_author] => 1 [post_date] => 2026-05-06 14:34:02 [post_date_gmt] => 2026-05-06 14:34:02 [post_content] => Princeton Hydro is proud to support the U.S. Army Corps of Engineers Baltimore District on the Atkisson Dam Removal project, an effort that prioritizes public safety, ecological restoration, and long-term watershed health in Harford County, Maryland. The Atkisson Dam and Reservoir are located along Winters Run, a 14.6-mile-long river that eventually becomes Otter Point Creek, flowing into the Bush River and eventually the Chesapeake Bay. Constructed in 1942, the concrete gravity dam once served as an auxiliary freshwater supply for Edgewood Arsenal operations. By the 1970s, however, the structure was no longer needed for that purpose. The dam is approximately 468 feet long, rising 46 feet at the spillway and nearly 60 feet at the abutments. Its central feature is a 210-foot-wide, uncontrolled ogee-type spillway, flanked by structural elements along both banks. [gallery link="none" size="medium" ids="19623,19630,19633"] Over time, the reservoir has become heavily silted following multiple storm events, and dense vegetation has encroached throughout the impounded area. Removal of the structure will eliminate potential long-term risks associated with dam failure while restoring the free flow of Winters Run, improving water quality and reconnecting habitat. Recently, Princeton Hydro’s geotechnical engineering team completed the first of several field efforts to support dam removal design. This phase involved a complex setup: mounting an SPT drilling rig onto a barge and navigating down the river to reach sampling locations within the former reservoir. Working from both land and water, the team collected critical geotechnical and sediment data that will inform safe and effective restoration. [gallery link="none" ids="19631,19638,19625"] [gallery link="none" ids="19626,19628,19634"] Geotechnical Engineer and Certified Construction Specifier Matthew Pappas led on-site coordination. Geotechnical Engineer Marissa Ciocco, PE, joined the team on the barge during drilling days, supporting field coordination and sample collection under challenging conditions. [gallery link="none" ids="19627,19629,19624"] Future efforts will include direct push sampling using a Marsh Master, along with hand auger investigations, followed by laboratory testing of collected samples. Together, these data will inform a design that addresses sediment management, site safety, and long-term stream stability following dam removal. As the Atkisson Dam Removal project moves forward, we look forward to sharing more updates from the field and highlighting the collaborative efforts that make meaningful restoration possible. [post_title] => Atkisson Dam Removal: Supporting River Restoration on Winters Run [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => atkisson-dam-removal [to_ping] => [pinged] => [post_modified] => 2026-05-06 14:34:02 [post_modified_gmt] => 2026-05-06 14:34:02 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=19607 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 19654 [post_author] => 1 [post_date] => 2026-05-04 18:32:16 [post_date_gmt] => 2026-05-04 18:32:16 [post_content] => 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:
Princeton Hydro is proud to support the U.S. Army Corps of Engineers Baltimore District on the Atkisson Dam Removal project, an effort that prioritizes public safety, ecological restoration, and long-term watershed health in Harford County, Maryland.
The Atkisson Dam and Reservoir are located along Winters Run, a 14.6-mile-long river that eventually becomes Otter Point Creek, flowing into the Bush River and eventually the Chesapeake Bay. Constructed in 1942, the concrete gravity dam once served as an auxiliary freshwater supply for Edgewood Arsenal operations. By the 1970s, however, the structure was no longer needed for that purpose. The dam is approximately 468 feet long, rising 46 feet at the spillway and nearly 60 feet at the abutments. Its central feature is a 210-foot-wide, uncontrolled ogee-type spillway, flanked by structural elements along both banks.
Over time, the reservoir has become heavily silted following multiple storm events, and dense vegetation has encroached throughout the impounded area. Removal of the structure will eliminate potential long-term risks associated with dam failure while restoring the free flow of Winters Run, improving water quality and reconnecting habitat.
Recently, Princeton Hydro’s geotechnical engineering team completed the first of several field efforts to support dam removal design. This phase involved a complex setup: mounting an SPT drilling rig onto a barge and navigating down the river to reach sampling locations within the former reservoir. Working from both land and water, the team collected critical geotechnical and sediment data that will inform safe and effective restoration.
Geotechnical Engineer and Certified Construction Specifier Matthew Pappas led on-site coordination. Geotechnical Engineer Marissa Ciocco, PE, joined the team on the barge during drilling days, supporting field coordination and sample collection under challenging conditions.
Future efforts will include direct push sampling using a Marsh Master, along with hand auger investigations, followed by laboratory testing of collected samples. Together, these data will inform a design that addresses sediment management, site safety, and long-term stream stability following dam removal. As the Atkisson Dam Removal project moves forward, we look forward to sharing more updates from the field and highlighting the collaborative efforts that make meaningful restoration possible.
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.
From tidal estuaries and back bays to nearshore marine waters, New Jersey’s coastal environments support fisheries, recreation, wildlife, and local economies. Increasingly, however, these valuable ecosystems are vulnerable to a wide range of harmful algal blooms (HABs). While algae are a natural and essential part of aquatic ecosystems, certain environmental conditions can cause some species to grow excessively, leading to ecological damage, public health risks, and economic losses.
Understanding what HABs are, what drives them, and how nature‑based restoration strategies can prevent or mitigate blooms is essential to supporting the long‑term resilience of New Jersey’s coastal environments.
The term "algae" is ecological rather than taxonomic and encompasses a diverse group of organisms, including eukaryotic algae, such as diatoms and dinoflagellates, and prokaryotic cyanobacteria, commonly referred to as blue‑green algae. Algae are not inherently harmful. In fact, they provide critical ecosystem services, including:
Phytoplankton are microscopic, free‑floating algae found in freshwater, estuarine, and marine environments. Scientists estimate there are 20,000 to more than 100,000 phytoplankton species, but only a small fraction—roughly 100 to 300 species—are capable of forming toxin‑producing harmful algal blooms. Problems arise when these species proliferate rapidly under favorable conditions. These blooms can become harmful when they produce toxins, deplete oxygen, shade submerged vegetation, or otherwise disrupt ecosystem function.
While most harmful algal blooms are caused by phytoplankton, large, fast‑growing macroalgae can also create serious environmental and economic challenges when conditions allow them to proliferate. A well‑known example is Sargassum, a floating seaweed that can form extensive mats across the ocean surface. During periods of rapid growth, these mats can block sunlight from reaching coral reefs and other sensitive habitats. When Sargassum washes ashore in large quantities, it can deter tourism and recreation. As the algae decomposes, it releases hydrogen sulfide gas, producing strong odors that make nearby coastal areas unpleasant to visit. While Sargassum blooms occur most summers along the coast of south Florida, the severity and extent of these events vary considerably from year to year.
HABs can form in freshwater systems, brackish estuaries, and coastal marine waters, and they are particularly dangerous with myriad when they produce toxins that affect humans, pets, livestock, fish, shellfish, and wildlife.
Below is a closer look at the dominant types of marine HABs in the region, the organisms responsible, and the environmental conditions that influence their development.
Brown tides are associated with several diatom genera, such as:
These blooms are influenced by a combination of physical, chemical, and climatic factors, including:
Ulva, commonly known as sea lettuce, is a green macroalga that can form extensive blooms in shallow, nutrient‑rich estuaries. Another common bloomer, Enteromorpha, is now considered genetically equivalent to Ulva. Although Ulva blooms are non‑toxic, they can still cause serious ecological and social impacts:
Cyanotoxins should not be confused with taste‑and‑odor (T&O) compounds. Cyanotoxins are colorless, tasteless, and odorless whereas T&O compounds, such as geosmin and MIB, cause earthy or musty smells. Cyanobacteria can produce T&O compounds without toxins as well as toxins without noticeable odors.
This distinction can complicate detection and public perception of risk.
These HABs, the region's most common, illustrate the wide range of organisms, toxins, and ecological pathways through which algal blooms can affect coastal systems. Although they differ in form, from microscopic phytoplankton to expansive mats of macroalgae, they are often driven by a common set of environmental conditions that favor rapid growth and persistence. Climate change is intensifying many of these drivers. Rising water temperatures, altered precipitation patterns, and longer periods of stratification increasingly create conditions that favor bloom formation. At the same time, human activities continue to increase excess nutrients to coastal waters. Runoff from agricultural lands, chemicals transported by rainfall and irrigation, and discharges from wastewater treatment facilities all introduce nitrogen and phosphorus into rivers, lakes, and estuaries. These nutrients act as fertilizer for algae, accelerating bloom development.
Nutrient‑laden stormwater runoff does not remain localized, rather, it moves downstream through interconnected watersheds, ultimately reaching estuaries and coastal waters where it can contribute to marine blooms. Understanding these linkages between land use, climate, and algae growth is critical to identifying effective strategies for preventing and managing HABs in coastal environments.
This Earth Day, students from Foundation Academy Collegiate in Trenton, NJ took their learning beyond the classroom through an immersive placemaking workshop hosted by Princeton Hydro. Designed as a real‑world, community‑based challenge, the experience invited students to reimagine a section of Trenton currently under study as part of the proposed Route 29 relocation project, which aims to reconnect the community to the Delaware River.
The goal was simple but powerful: give students a firsthand look at how planning, engineering, and community engagement shape the places they live, and let them experience those processes in action.
To start the workshop, students explored the basics of land use, Trenton’s development history, and the many steps that go into shaping an engineering project. They learned how planning, engineering design, permitting, construction, funding, and community engagement all work together to influence what gets built and why. With support from the "experts," they analyzed printed maps and photos of the selected site, identifying existing conditions and imagining what could be improved.
Once the activity began, the room quickly transformed into a bustling design studio. Each group received a large map of the site and a spread of crafting materials like blocks, clay, paper, and markers. From there, they built their vision for a future Trenton.
Some groups focused on green space and walkability. Others imagined mixed‑use corridors, safer crossings, or new community gathering areas. A few even experimented with stormwater‑friendly designs, weaving in concepts they had learned earlier in the session.
Throughout the activity, the "experts" from Princeton Hydro including an Engineer, Environmental Scientist, Grant Writer, Communications Specialist, Landscape Architect, and Wildlife Biologist, moved between tables, answering questions, offering technical insight, and encouraging students to think about how different stakeholders might view the same space. Residents, businesses, commuters, environmental groups, and city officials all bring different priorities to the table, and the students quickly discovered how complex those perspectives can be. The students were challenged with questions like "How are you going to fund this project?" "What's your engagement strategy to sell this to your peers?" and "How are you going to manage potential flooding from the river or stormwater in the park?"
Becky Taylor, a longtime Trenton advocate, co‑chair of the Cadwalader Park Alliance, and leader of Trenton Walks! also joined the teaching team for the day. Her work supporting Cadwalader Park’s restoration and experience leading dozens of walks throughout the City has connected her deeply with residents across the city. She is a strategic public affairs executive and small business owner, so as she engaged with students, she encouraged them to think about how public spaces carry history, identity, and community memory, and how thoughtful design can help strengthen those connections.
The students also learned something planners and engineers know well: There is rarely a single right answer. Every design choice involves tradeoffs, and every community space should reflect the values of the people who help shape it.
After building their models, each group presented their development plan to the room as if they were selling their vision to their local community in a public meeting. They explained their design choices, highlighted community needs, and described how their ideas could improve quality of life for residents.
The presentations were thoughtful, creative, and deeply rooted in the students’ lived experience. Many spoke about wanting safer streets, more places to gather, and greener, more welcoming public spaces. Others emphasized the importance of honoring Trenton’s history while planning for its future. They designed features such as a flower garden, a pier for fishing, a stormwater park, wildlife habitat, sports fields, and a kid's playground. One group proposed to elevate the new Route 29 so that the community could walk directly from downtown to their new riverfront park without safety issues of crossing a road. Another group deemed the waterfront development "Trenton 2.0" with trees lining the riverfront, renewable wind energy, and raised housing.
For our team, this workshop reinforced what we already know to be true: youth engagement in STEAM education matters. Young people notice how a place feels to move through, where it feels safe or unsafe, and what kinds of spaces are missing in their daily lives. When given the tools, they articulate those needs with confidence. They also tend to think collaboratively, naturally considering community needs alongside their own.
By learning how land use works and seeing the steps behind planning and development, students begin to understand how decisions are made and how those decisions affect the character of their neighborhoods. Most importantly, they start to see themselves as active participants in shaping their city rather than passive observers. Their insights help ground planning conversations in lived experience, and their voices strengthen the long‑term vision for any community project.
We are grateful to Foundation Academies for spending Earth Day with us and for bringing their energy and insight to this design challenge. As the Route 29 relocation/waterfront study continues, we remain committed to creating opportunities for meaningful participation, especially from young people who will inherit the outcomes of today’s planning decisions.
Earth Day is more than a date on the calendar! It’s a gentle nudge to reconnect with the natural world around us, and a reminder that everyday actions can shape a more sustainable future. Whether you’re tending a garden, removing invasive plants, or picking up litter while out on a walk, these small steps add up to a healthier, more resilient planet. This year, our team found a few fun and meaningful ways to mark the occasion, and we hope this inspires you to get outside and get growing, too.
Spring is the perfect season to take action in your yard or community green space. Whether you’re a seasoned gardener or just starting out, here are a few tips from our team to help your garden thrive:
Looking for more tips? Princeton Hydro landscape architects Jamie Feinstein, RLA and Cory Speroff, PLA, ASLA, CBLP shared their top spring gardening tips in an "Ask Me Anything" Facebook live Q&A session, including:
To welcome spring and celebrate Earth Day, members of the Princeton Hydro team spent an afternoon outside tending the native garden bed at the Trenton headquarters. Located at the front of the building, the perennial planting area features climate-adapted, drought-resistant native species chosen for their ecological benefits and aesthetic appeal.
Although perennials return year after year, they still benefit from seasonal care. Tasks like weeding, pruning, and loosening the soil support strong root systems, encourage healthy growth, and help maintain a thriving, sustainable garden ecosystem. Recognizing the garden's significance and the value of collaboration, our team united to accommodate and nurture this year's growth.
Feeling inspired? Organizing a gardening day is a fun, low-cost way to give back to your environment and bring people together. Celebrate Earth Day 2025 by starting a garden, volunteering with a local environmental group, or organizing your own mini planting day with friends, family or coworkers.
Rain gardens are a beautiful, low-maintenance green infrastructure solution for managing stormwater, reducing erosion, and improving water quality by filtering pollutants before they reach local waterways. They also provide valuable habitat for pollinators and other beneficial wildlife.
Princeton Hydro President Geoffrey M. Goll, P.E. led a free public workshop on how to build a rain garden of your own. Hosted in Yardley, PA by the Lower Makefield Township Environmental Advisory Council as part of their Environmental Lecture Series, the session offered practical, approachable guidance for managing stormwater at home.
Using photos from his own yard, Geoffrey walked attendees through how he designed and installed a rain garden to reduce runoff and eliminate pooling water. He shared ten easy-to-follow tips and answered questions on plant selection, drainage strategies, long-term maintenance, and when and why to amend soil before planting.
Want to learn more? Watch Geoffrey’s full presentation and get inspired to create your own eco-friendly solution to stormwater management:
The real spirit of Earth Day lies in our ongoing commitment to care for the natural world, not just once a year, but in everyday choices and community actions. As Geoffrey quoted in his rain garden presentation, "Small acts, when multiplied by millions of people, can transform the world." – Howard Zinn.
In developed watersheds, stormwater behavior is fundamentally altered by impervious surfaces and aging infrastructure, which can result in erosion, localized flooding, and nutrient pollution in surrounding waterways. These challenges rarely have simple or universal solutions, particularly in communities where natural systems, critical infrastructure, and public safety intersect within constrained landscapes.
How practitioners navigate these challenges and decide when to rely on green, gray, or hybrid stormwater solutions was the focus of a recent educational session at The Watershed Institute’s 9th Annual New Jersey Watershed Conference. The session, led by Princeton Hydro Water Resources Engineer Sean Walsh, PE and Landscape Architect Jamie Feinstein, RLA, alongside the Mayor of Lambertville (NJ) Andrew Nowick, explored how context‑driven design informs effective stormwater and erosion control strategies in developed environments.
Drawing from three real‑world case studies, the presenters examined how surrounding land use, physical constraints, risk tolerance, and stakeholder priorities shape decision‑making and why the most effective stormwater solutions are rarely one‑size‑fits‑all. This blog summarizes key lessons from that presentation, highlighting how site‑specific conditions ultimately determine whether green infrastructure, gray infrastructure, or a hybrid approach is the most appropriate tool for managing erosion, sediment, and flooding in settings shaped by competing land‑use and infrastructure demands.
Green infrastructure is designed to manage stormwater by mimicking natural hydrologic and geomorphic processes that are often altered or suppressed by development. Practices such as floodplain reconnection, step pools, riparian buffers, naturalized detention basins, and restored stream channels slow runoff, promote infiltration, and moderate sediment transport, while also improving water quality. When implemented at appropriate scales, these approaches can increase green space within built and urban environments, enhance habitat and biodiversity, and enrich the surrounding landscape by integrating stormwater management with ecological and recreational functions. However, the feasibility and performance of green infrastructure are highly dependent on site‑specific conditions, including available space, slope, and flow regimes, which are frequently constrained in urban environments.
Gray infrastructure, by contrast, is designed to prioritize conveyance, control, and predictability. Systems such as pipes, culverts, and engineered structures are well‑suited to managing high‑capacity flow rates, centralizing stormwater runoff, and conveying water safely through constrained environments. These approaches typically require smaller physical footprints than nature‑based alternatives and often involve lower long‑term maintenance demands. In developed settings, gray infrastructure can also provide critical structural support for roads, utilities, and other built infrastructure, offering a level of reliability and risk management that green infrastructure alone may not be able to achieve.
Determining the appropriate balance between green and gray infrastructure requires a clear understanding of site‑specific constraints, risks, and performance needs, an approach illustrated in the case studies that follow.
To explore how context drives design decisions, we recently examined three real‑world case studies, each involving active erosion, sediment transport, and downstream impacts, and each arriving at a different solution.
In Lambertville, New Jersey, stormwater runoff from Music Mountain, a steep, wooded hillside, was causing repeated flooding at the Fire Department below. What appeared at first to be a small drainage issue turned out to be a much larger challenge. During heavy rain events, uncontrolled runoff carved deep erosion gullies downslope, destabilizing trees and transporting sediment directly into city infrastructure. While green infrastructure options such as step pools were initially considered, feasibility limitations became evident. The steep slope, limited footprint, and extreme peak flows made a fully nature-based solution impractical and risky in this location.
Instead, the selected design centered on gray infrastructure, including a piped stormwater system aligned with the existing flow path to minimize disturbance, along with redesigned and expanded inlet and outlet controls to safely convey peak flows and better capture surface runoff. This approach stabilized the hillside, reduced downstream sediment transport, and eliminated flooding impacts at a critical municipal facility. Given the severe spatial constraints and elevated risk associated with the site, gray infrastructure represented the most responsible and effective solution.
At Holcombe Park, ongoing erosion and a disconnected floodplain were impairing stream function and contributing sediment and debris to downstream infrastructure. Unlike the Lambertville Fire Department site, where steep slopes, limited space, and public safety risks necessitated a primarily gray solution, Holcombe Park offered greater physical flexibility and a different risk profile. The site included more available space for in‑channel and floodplain interventions, while the contributing drainage system extended more than 1,000 feet beneath roadways before releasing flows downstream, adding jurisdictional and infrastructure considerations to the design process.
Given these conditions, the project team pursued a hybrid strategy that leveraged the strengths of both green and gray infrastructure. Green infrastructure measures, including floodplain reconnection, step pools, and naturalized channel features, were incorporated where space allowed to slow flows, reduce erosive forces, and restore ecological function. At the same time, existing gray infrastructure continued to convey stormwater through developed areas where open‑channel solutions were infeasible. By allowing floodwaters to spread out and attenuate within the park, the project reduces peak velocities and limits the transport of debris and sediment to downstream culverts and roadways. This case study illustrates how, when site conditions permit, integrating green and gray infrastructure can address erosion and water quality concerns while protecting downstream assets and enhancing recreational space, achieving outcomes that neither approach could deliver on its own.
The third case study shifts to a more open, rural setting on a residential and agricultural property in Pennsylvania, where channel incision and bank instability had become a growing safety and land‑use concern. Unlike the urban conditions present in the Lambertville Fire Department and Holcombe Park projects, this site offered sufficient space for stream and floodplain processes to function, making it well‑suited for a predominantly green infrastructure approach.
Initially, the landowner attempted to address the erosion by installing a large‑diameter pipe to rapidly convey water through the affected area. While this strategy appeared to resolve the immediate problem on site, it ultimately transferred impacts downstream. Concentrated discharges from the pipe destabilized channel banks, accelerated erosion, and created new problems beyond the property boundary, while also violating local waterway regulations. This outcome illustrated how applying gray infrastructure to a system experiencing watershed‑scale hydrologic change can unintentionally amplify downstream risks.
The final design focused on restoring natural stream function rather than accelerating conveyance. The project realigned the channel to an appropriate slope and sinuosity, reconnected the stream to its floodplain, incorporated step pools and stabilization features to dissipate energy, and added riparian plantings to strengthen bank stability and ecological resilience. Limited sections of pipe were retained only where necessary to accommodate crossings, ensuring compatibility with existing land uses without compromising system function.
With adequate space, funding, and regulatory drivers in place, natural green infrastructure proved to be the most effective and resilient solution for this site. By treating water as a resource rather than a waste product, the project reduced erosion and sediment transport, improved water quality, and restored stream and floodplain processes that benefit both the landscape and downstream communities. This case study also demonstrates that successful stormwater and erosion control requires solutions that respond to both local conditions and the larger watershed system.
Across all three projects, the lesson is clear: green or gray decisions must be driven by site context, not preference alone. Surrounding land use, physical constraints, risk tolerance, regulatory requirements, and stakeholder priorities all shape what “success” looks like.
Improperly sized or poorly applied infrastructure, whether it be green or gray, will fail. Effective stormwater management requires looking beyond the immediate problem and designing solutions that reflect the realities of the entire watershed system.
Princeton Hydro’s participation alongside Mayor Andrew Nowick in leading the educational session at the 2026 NJ Watershed Conference reflects a long‑standing partnership with the City of Lambertville and the City’s active role in applying context‑driven stormwater solutions in a constrained, developed watershed. Our team has supported Lambertville’s stormwater management initiatives for many years, working collaboratively with City leadership to design projects that mitigate flooding while enhancing the natural environment.
In September 2024, New Jersey Department of Environmental Protection Commissioner Shawn M. LaTourette presented the City of Lambertville with the NJDEP “Our Water’s Worth It” award. The award ceremony, held at a stormwater infrastructure improvement project site behind the Lambertville Fire Department, recognized the City’s commitment to improving stormwater management, addressing flooding, protecting local waterbodies, increasing storm resilience, and mitigating the impacts of climate change. Click here to learn more.
Charlie is a licensed Professional Engineer and a Certified Floodplain Manager with over five years of experience in water resources engineering. His expertise includes hydrologic and hydraulic modeling, green stormwater infrastructure, civil site design, ecological restoration, and flood resilience. Charlie holds a M.S. in Biological Systems Engineering and B.S. Environmental Science/B.A. Geography from Virginia Tech.
Prior to joining Princeton Hydro, Charlie worked as a Water Resources Engineer for Meliora Design, where he designed green stormwater infrastructure projects such as rain gardens and underground infiltration beds, created master plans for state and local parks, and modeled conceptual floodplain restoration studies for the Brandywine Creek Flood Study. Before Meliora, he worked at Kleinschmidt Associates where he worked on hydrologic and hydraulic projects such as dam breaches, dam removals, nature-like fishways, and FEMA LOMRs.
Outside of work, he likes to play ultimate frisbee and lead his local Environmental Advisory Council where he plans park invasive removals and tree giveaways.
Mike serves as the Business Administration and Compliance Manager at Princeton Hydro. He brings a unique perspective to the team, built over a 20-year career in the U.S. Air Force as a KC-10 Extender Boom Operator. During his time in the service, Mike did more than just fly; he managed global logistics missions and was responsible for the essential training, certification, and compliance of aircrew members.
After retiring from the military, Mike spent four years as a Senior Manager at Verizon, where he focused on business transformation and strategy. Today, he uses that background to lead our efforts in regulatory compliance, policy development, and keeping our administrative processes running smoothly.
Mike holds an MBA from Temple University and a B.S. in Business from Penn State. When he’s not in the office, you’ll likely find him cooking, traveling with his family, or tending to his woodworking projects, garden, and chickens.
Tyler graduated from the University of Rhode Island in 2024 with a B.S. in Environmental Science and Management. At URI, he began as a research assistant studying the rapid spread of aquatic invasive species throughout Rhode Island’s wetlands. Tyler later transitioned to marine systems, assisting a project at URI’s Graduate School of Oceanography investigating phytoplankton dynamics in the Gulf of Mexico. While studying abroad at the Universidad Católica de Valencia in Spain, Tyler researched the Mediterranean fan mussel and became Scuba certified.
Following his graduation, Tyler stayed with the Graduate School of Oceanography to complete a project aboard the RV/IB Nathaniel B. Palmer. Here, he researched phytoplankton blooms along Antarctica’s coast and across the Southern Ocean while also achieving his dream of setting foot on all seven continents.
During his free time, Tyler enjoys surfing, reading, playing music, and exploring Philadelphia, where he now lives.
Our newest team members are already making valuable contributions, and we’re excited to see their impact continue to grow. We’re so glad to have them as part of the team!
When it comes to restoring lakes and safeguarding watershed health, effective and sustainable solutions depend on science, partnerships, and sustained investment. Princeton Hydro Senior Manager of Aquatics Chris Mikolajczyk, CLM was invited as one of the select experts chosen to represent the North American Lake Management Society’s (NALMS) 314 Working Group in Washington, DC to contribute technical insight and real world expertise during discussions with congressional staff and U.S. Environmental Protection Agency (USEPA) leadership about the policies and funding resources that help communities across the country address nonpoint source pollution.
There are several federal funding programs that states, tribes, local governments, and nonprofits rely on to support critical water-quality improvement initiatives. Among them, Clean Water Act Section 319(h) is a cornerstone program that supports nonpoint source management projects like watershed-based planning, stormwater retrofits, riparian restoration, and targeted education programs. It is administered by USEPA and delivered through states and qualified tribes, and funding typically requires a nonfederal cost share to leverage local investment. In recent federal budget cycles, elements of this funding landscape have faced proposed reductions or complete eliminations by the current administration, including sharp reductions to the Clean Water and Drinking Water State Revolving Funds.
Against that backdrop, the NALMS 314 Working Group organized a bipartisan “fly in” to share data, case studies, and practical policy options with Senate offices and USEPA’s Office of Water, emphasizing how programs like Section 319 translate into measurable, local water quality gains. The group, which included Committee Member Mark Heilman; NALMS Board Member Ben Rhoades; government strategist Drue Winters; and NALMS Past-President Chris Mikolajczyk, CLM, held meetings with the offices of Senators Wicker (R-MS), Markey (D-MA), Alsobrooks (D-MD), and Sanders (D-VT); both majority and minority staff of the Senate Committee on Environment and Public Works; and the EPA Office of Water leadership.
Another focal point of the DC conversations was the National Lakes Assessment (NLA), a statistically rigorous survey of lake conditions conducted every five years by USEPA and its state and tribal partners. The most recent NLA, fielded in 2022, provides nationally consistent insight into ecosystem health, key stressors, and recreational indicators, and it helps policymakers understand where water quality is improving or declining and how to target investments.
Created under the Clean Water Act, Section 319(h) is one of the nation’s primary funding tools for tackling runoff driven water quality issues. Through this program, states and tribes can invest in incentive-based, nonpoint source pollution reduction projects. Examples of activities eligible for 319(h) funding include watershed-based planning, BMP implementation, education and outreach, and water quality assessment and monitoring.
Because 319(h) is administered through state programs, it supports local priorities while aligning with national goals. Over time, this approach has enabled communities to design watershed specific strategies, from agricultural and urban stormwater controls to nature-based green infrastructure, and to document water quality improvements with consistent methods. In most cases, a 40% non-federal funding match is required.
At Princeton Hydro, we’ve seen firsthand how Section 319(h) translates into action through state run grant programs. In New Jersey, the NJDEP Water Quality Restoration Grants support projects that reduce nonpoint source pollution, mitigate harmful algal blooms, restore riparian areas, enhance watershed and climate resilience, and restore water quality in New Jersey. The grants are funded through Section 319(h) and administered by NJDEP’s Watershed & Land Management Program.
Princeton Hydro is proud to be a partner on five of the 17 projects most recently awarded funding (2025) through NJDEP’s Water Quality Restoration grants. Our contributions vary by project and encompass activities such as engineering design, water quality assessment, watershed-based planning, and technical support for implementing stormwater and habitat restoration measures. We also supported several partners in developing successful NJDEP Section 319(h) applications, including technical documentation, cost estimates, conceptual designs, and pollutant load reduction estimates.
To take a deeper dive into our most recent collaborations, click here to read our blog: NJDEP Awards $8M for Water Quality Restoration Projects
Princeton Hydro is grateful to NALMS and our fellow 314 Working Group members for convening this effort, and to the Senate offices and USEPA leaders who engaged in thoughtful, solutions-oriented conversations. These conversations are already translating into tangible results.
Following these coordinated advocacy efforts Clean Water Act Section 319(h) funding was restored in the federal budget with an increase of $750,000. More broadly, the U.S. Environmental Protection Agency ultimately fared better than many federal agencies during the most recent budget cycle, with several programs initially proposed for reduction or elimination reinstated through congressional negotiations.
Chris Mikolajczyk is a Certified Lake Manager and aquatic ecologist with over 35 years of experience in conducting the management, oversight, and coordination of water resource projects in three main areas: aquatic resource restoration and management; aquatic ecosystem sampling and investigations; and stormwater quality modeling and management. Chris also manages the design and implementation of watershed restoration projects, many funded by EPA 319(h), such as structural BMPs; bio-engineering techniques for nutrient reduction; development of TMDL pollutant budgets; and watershed-based monitoring programs. To date, Chris has managed projects involving over 100 lakes and reservoirs. Chris has been a member of the North American Lake Management Society (NALMS) for over 20 years. In that time, he has served on the Board of Directors, chaired the Professional Certification Committee, and served as president from November 2021- November 2022. He currently serves as Board President for the Colorado Lake and Reservoir Management Association.
Princeton Hydro recently joined coastal and climate resilience practitioners from across the region at the 2026 New Jersey Coastal & Climate Resilience Conference, hosted by the New Jersey Coastal Resilience Collaborative (NJCRC) and the New Jersey Department of Environment Projection (NJDEP). With this year’s theme, “Navigating Changing Tides,” the three-day conference brought together hundreds of professionals to share ideas, explore solutions, and strengthen the partnerships essential to advancing coastal resilience.
As part of the conference program, Princeton Hydro's Director of Marketing & Communications Dana Patterson Grear organized a Sunrise Bird Walk at Edwin B. Forsythe National Wildlife Refuge, led by Mike McGraw, CSE, QAWB, ACE, Senior Wildlife Biologist at Princeton Hydro, alongside Drew McQuade and Aleshanee Mooney of the New Jersey Sports and Exposition Authority (NJSEA).
A group of 25+ participants traveled the eight‑mile loop along Wildlife Drive, collectively observing 62 bird species along the way. Highlights included two White Ibis, an Osprey perched on a nesting platform, and hundreds of Snow Geese. As the group approached the end of the loop, a Peregrine Falcon provided the perfect send-off, holding its perch on a refuge sign while the caravan rolled by.
Dr. Clay Emerson, PE, CFM, Senior Technical Director of Engineering Services, shared his perspective on New Jersey’s changing coastal environment and the role bay island restoration can play in protecting vulnerable shorelines.
Clay’s presentation explored how coastal dynamics, restoration design, and resilience planning intersect, offering practical insight into nature‑based strategies that support shoreline stability and long‑term adaptability. His ability to translate complex processes into clear, engaging concepts resonated strongly with the conference audience. Moderated by Tom Herrington of the Monmouth University Urban Coast Institute, Clay participated in a Q&A panel discussion with NOAA Coastal Resilience Fellow Heather Korzun and Research Scientist Dr. John Swartz of The Water Institute to conclude the "Building Community Resilience" breakout session.
Dr. Fred Lubnow, Senior Technical Director of Ecological Services, gave a poster presentation focused on Harmful Algal Blooms (HABs) in coastal environments.
Fred’s work examined how HABs behave in dynamic coastal systems, how to identify HABs, and restoration strategies. In the context of the conference theme, his presentation reinforced that HABs are not just seasonal nuisances, but long‑term resilience challenges that require integrated science, monitoring, and restoration approaches.
As part of the conference's Tools Café, Dana Patterson Grear, Director of Marketing & Communications, led a digital storytelling demonstration, titled “Launching an Interactive ArcGIS StoryMap for Public Outreach.” The session demonstrated how digital tools like StoryMaps can be used to translate complex data into accessible narratives that support community engagement, education, and informed decision‑making. Dana guided participants through several ArcGIS StoryMaps created by Princeton Hydro for clients and project partners, showcasing applications ranging from restoration projects and environmental resource inventories to water quality assessments and community science initiatives.
Princeton Hydro was proud to host a conference networking event alongside co‑sponsors Stantec, Baird, and Barnegat Oyster Collective. The gathering created space for conversation, collaboration, and relationship‑building, an essential part of advancing coastal resiliency initiatives and cross‑disciplinary problem‑solving. Attendees enjoyed brief remarks from each of the event sponsors, along with happy‑hour refreshments, and a complimentary oyster bar provided by the Barnegat Oyster Collective. Our team had a great time connecting with colleagues and celebrating the collaborative energy that defined the conference.
Another highlight of the conference for our team was a field trip to The Nature Conservancy in New Jersey’s South Cape May Meadows, where participants explored the newly completed boardwalk, a Princeton Hydro-designed project that creates a half‑mile, universally accessible route through one of the region’s most ecologically significant landscapes. Commissioned by The Nature Conservancy in New Jersey and installed by Renova Environmental Company, the project was designed to provide inclusive public access and opportunities for environmental education while carefully protecting a fragile ecosystem that serves as a vital stopover along the Atlantic Flyway.
Designing a public trail within such a dynamic wetland system required a careful balance between human experience and habitat preservation, with the goal of creating an inviting, educational, and fully accessible route without disturbing critical hydrology, soils, or wildlife. Walking the boardwalk alongside fellow NJCRC Conference participants was a meaningful, full-circle moment for our team, bringing the project’s vision to life.
Huge thanks to New Jersey Coastal Resilience Collaborative and New Jersey Department of Environmental Protection for pulling together another incredible conference. We headed home with new connections, new ideas, and a renewed sense of pride in the work we all do!
Nutrient-driven water quality impairments, particularly harmful algal blooms (HABs), continue to challenge lake managers, municipalities, and watershed organizations across the Northeast. Excess phosphorus and nitrogen can rapidly degrade ecological conditions, limit recreational use, impact sources of potable water, and increase management costs, often despite the implementation of conventional best management practices. As a result, there is growing interest in tools that can complement or augment existing approaches and address nutrients in more targeted ways.
Biochar has emerged as one such tool. While it is best known as a soil amendment, its physical, chemical, and biological properties have prompted increasing use in aquatic systems as a means of improving water quality. Over the past five years, Princeton Hydro has applied biochar in a range of lakes, ponds, streams, and stormwater-related settings across Pennsylvania, New Jersey, and New York. These field applications, supported by monitoring, have provided important insight into when biochar is most effective, where its limitations lie, and why observed improvements in water quality are not always explained by phosphorus removal alone.
Biochar is a carbon-rich, charcoal-like material produced through pyrolysis, a process in which organic biomass is heated in a low-oxygen environment. The resulting material has a highly porous structure and extensive surface area, properties that make it effective at adsorbing nutrients such as phosphorus and nitrogen (Joseph et al., 2021). Because excess nutrients are a primary driver of eutrophication and HABs, biochar has emerged as a promising amendment for aquatic systems and stormwater best management practices (BMPs).
In aquatic applications, biochar is typically installed in permeable sleeves (aka socks) or incorporated into stormwater treatment practices to intercept nutrient-rich water before it enters lakes or ponds. Used biochar can also be repurposed as a soil amendment, adding to its appeal as a sustainable, circular material.
Through approximately half a dozen monitored projects implemented since 2020, several consistent patterns have emerged.
Standing Waters Show the Strongest Response: Biochar has proven most effective in low-flow or standing water environments such as ponds and stormwater basins. In these systems, Princeton Hydro has documented total phosphorus (TP) removal rates as high as 80%, with soluble reactive phosphorus (SRP) reductions approaching 97% in some stormwater ponds (Princeton Hydro, Lake Hopatcong Report, 2022). The extended contact time between water and biochar in these settings appears to be a key driver of performance.
Flow and Contact Time Matter: In streams and fast-moving stormwater infrastructure, nutrient removal rates tend to be lower, with phosphorus reductions typically closer to 50%. While still meaningful, these reduced efficiencies are largely attributable to limited contact time. Simply put, the shorter the interaction between water and biochar, the fewer opportunities there are for adsorption and other removal processes to occur.
Enhancement to Conventional Stormwater BMPs: Biochar can be particularly effective when paired with stormwater BMPs that primarily rely on sedimentation. Traditional practices often excel at removing particulate-bound phosphorus but are less effective at capturing dissolved forms of phosphorus—the fraction most readily utilized by algae. Incorporating biochar into these systems can enhance removal of dissolved phosphorus, improving overall treatment performance.
Streams Present Physical Challenges: Installing biochar in stream environments presents practical challenges. Even with careful anchoring, large storm events, including remnants of hurricanes, can dislodge biochar sleeves, transporting them downstream or onto streambanks. These risks must be considered during design and often limit the suitability of biochar for higher energy systems.
Chemistry Alone Does Not Tell the Whole Story: At very high pH levels, phosphorus adsorption onto biochar can become less predictable, sometimes exhibiting a “decoupling” between measured phosphorus sorption and observed water quality improvements. Monitoring data from multiple projects indicate that reductions in chlorophyll-a, cyanobacteria abundance, and overall bloom severity cannot always be explained by phosphorus removal alone.
The disconnect between measured nutrient sorption and improved water quality suggests that additional mechanisms are at work. Increasingly, evidence points toward biological processes occurring within and around biochar installations.
Biochar is known to favor the growth and proliferation of heterotrophic bacteria (Moore et al., 2023). These microbial communities may contribute to water quality improvements in the following ways:
This emerging science mirrors what Princeton Hydro has observed in the field: water quality can improve in ways that chemical measurements alone do not fully explain, suggesting that biological processes may be playing an important supporting role.
Since 2020, Princeton Hydro has applied biochar across a range of aquatic and stormwater settings, tailoring each installation to site-specific conditions and management goals. Together, these projects demonstrate biochar’s versatility and its ability to integrate into holistic watershed and lake management strategies, often working best when paired with other nature-based and engineered solutions.
At Duke Farms, a 2,700-acre estate in New Jersey, Princeton Hydro has supported lake and wetland management efforts for more than two decades. Biochar was recently introduced as an additional tool within an established, science-based nutrient management program. By placing biochar in low-flow areas where contact time could be maximized, phosphorus removal was enhanced and improvements in water clarity were observed. This effort highlights how biochar can be layered into long-term management strategies alongside floating wetland islands and other nature-based solutions.
Harvey’s Lake, the largest natural lake in Pennsylvania, has long faced challenges associated with nutrient loading and recurring HABs. As part of a broader stormwater management effort, Princeton Hydro incorporated biochar into select stormwater BMPs to reduce phosphorus before it entered the lake. Installed within targeted stormwater conveyance and treatment features, the biochar helped achieve measurable reductions in dissolved phosphorus, complementing other watershed-scale measures such as vegetated buffers and wetland enhancements. The spent biochar, having captured phosphorus and nitrogen from runoff, was then repurposed as a soil amendment to enrich a 500-square-foot pollinator garden. This repurposing effort served a dual purpose: demonstrating a closed-loop approach to managing excess nutrients while also creating a community-oriented space that supports local biodiversity.
Across multiple stormwater projects in New Jersey and Pennsylvania, biochar has been installed in detention basins, rain gardens, and other stormwater treatment devices. These applications were designed to target dissolved phosphorus, a nutrient form that conventional BMPs can struggle to remove. In several cases, biochar was paired with other nutrient control measures such as floating wetland islands to further improve nutrient capture. Collectively, these projects illustrate how biochar can be adapted and scaled to address local water quality challenges across diverse settings.
At Lake Hopatcong, New Jersey’s largest lake, biochar was deployed as part of a comprehensive, multi-pronged strategy to reduce nutrient concentrations and mitigate HABs. Biochar was installed in permeable flotation bags and placed at targeted shoreline and inlet locations where nutrient loading is most pronounced, including several stormwater inlets and outlets around the lake. Funded through the NJDEP Freshwater HABs Prevention & Management Grant Program and implemented in partnership with the Lake Hopatcong Commission and the Lake Hopatcong Foundation, these installations complemented other in-lake management measures such as floating wetland islands.
In Manhattan's Central Park, Princeton Hydro supported the Central Park Conservancy in developing and implementing a long-term management strategy for the park's network of lakes and ponds, where harmful algal blooms driven by excess nutrients were a persistent concern. As part of a broader, phased approach to improve water quality, biochar was incorporated as a nutrient reduction tool and will be incorporated alongside other measures such as floating wetland islands, aeration and circulation, and stormwater treatment techniques. Used in targeted locations, biochar helped support efforts to reduce nutrient loading and mitigate cyanobacteria blooms within these highly visible urban waterbodies.
Across these projects, biochar installations have been associated with measurable reductions in total and dissolved phosphorus, decreases in chlorophyll‑a concentrations, and lower cyanobacteria cell counts. While performance has varied by site, the strongest and most consistent results have occurred in enclosed or low‑flow environments where contact time is maximized and physical disturbance is minimized. When thoughtfully designed and integrated with other BMPs, these case studies show how biochar can contribute meaningfully to broader efforts to reduce nutrient loads and improve overall water quality.
Biochar is not a one-size-fits-all solution. Reviewing site-specific water quality data is essential to determine whether biochar is an appropriate standalone treatment or should be combined with complementary approaches. Ongoing and future research is focused on better quantifying the relative contributions of chemical adsorption and biological activity associated with biochar. Current studies, including collaborative efforts with academic partners, aim to document pollutant removal capacity, characterize microbial communities, and evaluate biochar’s potential role in degrading cyanobacteria and cyanotoxins. As these processes continue to be studied and further understood in the water quality context, biochar may become an increasingly valuable component of integrated, science-based watershed management strategies.
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