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.
WP_Query Object ( [query] => Array ( [page] => [pagename] => blog ) [query_vars] => Array ( [page] => 0 [pagename] => blog [error] => [m] => [p] => 0 [post_parent] => [subpost] => [subpost_id] => [attachment] => [attachment_id] => 0 [name] => [page_id] => 0 [second] => [minute] => [hour] => [day] => 0 [monthnum] => 0 [year] => 0 [w] => 0 [category_name] => climate-change [tag] => [cat] => 1 [tag_id] => [author] => [author_name] => [feed] => [tb] => [paged] => 1 [meta_key] => [meta_value] => [preview] => [s] => [sentence] => [title] => [fields] => all [menu_order] => [embed] => [category__in] => Array ( [0] => 1 ) [category__not_in] => Array ( ) [category__and] => Array ( ) [post__in] => Array ( ) [post__not_in] => Array ( ) [post_name__in] => Array ( ) [tag__in] => Array ( ) [tag__not_in] => Array ( ) [tag__and] => Array ( ) [tag_slug__in] => Array ( ) [tag_slug__and] => Array ( ) [post_parent__in] => Array ( ) [post_parent__not_in] => Array ( ) [author__in] => Array ( ) [author__not_in] => Array ( ) [search_columns] => Array ( ) [posts_per_page] => 11 [ignore_sticky_posts] => [suppress_filters] => [cache_results] => 1 [update_post_term_cache] => 1 [update_menu_item_cache] => [lazy_load_term_meta] => 1 [update_post_meta_cache] => 1 [post_type] => [nopaging] => [comments_per_page] => 5 [no_found_rows] => [order] => DESC ) [tax_query] => WP_Tax_Query Object ( [queries] => Array ( [0] => Array ( [taxonomy] => category [terms] => Array ( [0] => 1 ) [field] => term_id [operator] => IN [include_children] => ) ) [relation] => AND [table_aliases:protected] => Array ( [0] => ph_term_relationships ) [queried_terms] => Array ( [category] => Array ( [terms] => Array ( [0] => 1 ) [field] => term_id ) ) [primary_table] => ph_posts [primary_id_column] => ID ) [meta_query] => WP_Meta_Query Object ( [queries] => Array ( ) [relation] => [meta_table] => [meta_id_column] => [primary_table] => [primary_id_column] => [table_aliases:protected] => Array ( ) [clauses:protected] => Array ( ) [has_or_relation:protected] => ) [date_query] => [queried_object] => WP_Post Object ( [ID] => 6 [post_author] => 1 [post_date] => 2021-01-18 12:51:43 [post_date_gmt] => 2021-01-18 12:51:43 [post_content] => [post_title] => Blog [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => blog [to_ping] => [pinged] => [post_modified] => 2021-01-18 12:51:43 [post_modified_gmt] => 2021-01-18 12:51:43 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?page_id=6 [menu_order] => 0 [post_type] => page [post_mime_type] => [comment_count] => 0 [filter] => raw ) [queried_object_id] => 6 [request] => SELECT SQL_CALC_FOUND_ROWS ph_posts.ID FROM ph_posts LEFT JOIN ph_term_relationships ON (ph_posts.ID = ph_term_relationships.object_id) WHERE 1=1 AND ( ph_term_relationships.term_taxonomy_id IN (1) ) AND ((ph_posts.post_type = 'post' AND (ph_posts.post_status = 'publish' OR ph_posts.post_status = 'acf-disabled'))) GROUP BY ph_posts.ID ORDER BY ph_posts.menu_order, ph_posts.post_date DESC LIMIT 0, 11 [posts] => Array ( [0] => WP_Post Object ( [ID] => 18888 [post_author] => 1 [post_date] => 2025-12-16 16:04:21 [post_date_gmt] => 2025-12-16 16:04:21 [post_content] => Friends of Hopewell Valley Open Space (FoHVOS), in partnership with Princeton Hydro, has launched a groundbreaking initiative, “Monitoring Harmful Algal Blooms (HABs) in the Delaware River Watershed Using Drones and Spatial Analysis,” to improve understanding and forecasting of HABs throughout the Delaware River Watershed. Funded by the National Fish and Wildlife Foundation (NFWF), in partnership with the U.S. Fish & Wildlife Service, through the Delaware Watershed Conservation Fund (DWCF), 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. For this innovative research project, FoHVOS, a 501(c)3 and accredited Land Trust located in Hopewell Township, NJ, has teamed with Princeton Hydro. Princeton Hydro conceptualized and designed the initiative and is leading the technical implementation, including field survey design, drone operations, data analysis, and volunteer training. “The Delaware River is central to Hopewell Valley’s identity. It shapes our way of life, supplies drinking water to 14.2 million people, shelters wildlife like the endangered Atlantic sturgeon, and offers abundant outdoor recreation,” said Jennifer Rogers, Executive Director of FoHVOS. “HABs were once confined to ponds and lakes, but since 2018, they’ve appeared in colder months and spread to streams and rivers. Though land trusts traditionally focus on land, HABs show how land use directly affects water. These blooms often stem from excess nitrogen and phosphorus washed into waterways during storms. Protecting water means restoring land. Our partnership with Princeton Hydro aligns perfectly with our mission. Together, we’re working to better understand and safeguard the Delaware River and its tributaries in both NJ and PA.” HABs, caused by nuisance growth of cyanobacteria, can have detrimental effects on water quality and are a growing environmental concern nationwide. These blooms deplete oxygen levels, release toxins, and disrupt ecosystems, potentially posing serious risks to drinking water supplies and the health of wildlife, pets, humans, and local economies. Despite advances in environmental monitoring, predicting when and where HABs will occur remains a challenge due to the complex interplay of nutrient loading, temperature, and hydrologic conditions that can lead to rapid bloom proliferation. To address these challenges, this newly launched initiative integrates drone-based remote sensing, field sampling, and spatial data analysis to collect and interpret detailed environmental data over a two-year period. The study spans multiple monitoring sites along a 73-mile stretch of the Delaware River in New Jersey and Pennsylvania, focusing on near-shore sections and 23 associated waterbodies. The first survey event began in August 2025. 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. The following photos depict the RGB (Visual) and corresponding Thermal image from the monitoring flights over Spring Lake in New Jersey: [gallery columns="2" link="none" size="medium" ids="18899,18900"] “This research project represents a major step forward in how we study and manage harmful algal blooms at the watershed scale,” said Dr. Fred Lubnow, Project Lead and Senior Technical Director of Ecological Services at Princeton Hydro. “By integrating satellite data, drone imagery, and on-the-water sampling, we’re developing predictive tools that will enable us take a proactive approach to mitigate HABs, improve response time, and better support our ecosystem health.” Project partners include New York City College of Technology – The City University of New York, which donated the drone and is supporting remote sensing and data integration; Trenton Water Works, Mercer County Park Commission, and The College of New Jersey which are providing monitoring sites and contributing volunteers for water quality data collection in New Jersey; Aqua-PA and the Philadelphia Water Department, which are providing monitoring sites and volunteers to collect watershed data in Pennsylvania; the Bucks County Conservation District, which is coordinating volunteer data collection; and Turner Designs, whose advanced phycocyanin sensors are being used to calibrate and validate drone-based monitoring data. In the photos below, volunteers are being trained by Princeton Hydro staff on how to use phycocyanin fluorometers and Secchi disks to gather water quality data and log their findings. [gallery link="none" size="medium" ids="18896,18895,18894,18897,18891,18892"] This $1M project is funded through a $488,400 NFWF DWCF grant as part of the NFWF’s Research, Monitoring, & Evaluation Grant category and $513,700 in matching funds from project partners. This grant category aims to support high-performing science that is inclusive, adaptive, and innovative, with the potential to transform the Delaware River Watershed’s future through improved conservation, restoration, and public engagement. Once complete, the project will produce a comprehensive report summarizing methods, analyses, and data-driven recommendations for practical, low-cost HAB monitoring and mitigation strategies that can be replicated across the Delaware River Watershed and beyond. Crucially, the report will identify tributaries and sources contributing to riverine HABs, enabling targeted restoration of the most affected lands and waters. Data collection will continue through Fall 2025, resume in Spring/Summer 2026, and culminate in a final report expected in 2027. [gallery link="file" columns="2" ids="18781,18902"] FoHVOS is a 501(c)3 nonprofit land trust dedicated to conserving the natural resources of the Hopewell Valley region and beyond. Through land preservation, ecological restoration, community engagement, and science-driven initiatives, FoHVOS works to protect and enhance open spaces for future generations. Learn more at www.fohvos.org. Princeton Hydro is committed to improving our ecosystems, quality of life, and communities for the better. The firm was formed in 1998 with the specific mission of providing integrated ecological and engineering consulting services. Offering expertise in natural resource management, water resources engineering, geotechnical design and investigation, and regulatory compliance, their staff provide a full suite of environmental services throughout the Northeast for the public and private sectors. Project Lead, Dr. Fred Lubnow, is an expert in HAB management and has worked with dozens of lake associations and government agencies to restore lakes, manage watersheds, reduce pollutant loading, address invasive aquatic plants, and mitigate nuisance HABs. To learn more about Princeton Hydro's work to mitigate harmful algal blooms, go here. [post_title] => Innovative Drone-Based Research Study to Predict HABs in the Delaware River Watershed [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => innovative-drone-based-research-study-to-predict-habs-in-the-delaware-river-watershed [to_ping] => [pinged] => [post_modified] => 2025-12-16 16:12:45 [post_modified_gmt] => 2025-12-16 16:12:45 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=18888 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 18641 [post_author] => 1 [post_date] => 2025-12-08 13:22:27 [post_date_gmt] => 2025-12-08 13:22:27 [post_content] => The Lower Darby Creek Area encompasses a unique blend of residential neighborhoods, commercial zones, and critical regional infrastructure, including the Philadelphia International Airport, Interstate 95, and portions of the John Heinz National Wildlife Refuge. Despite its urban setting, the area supports diverse wetlands, waterways, and wildlife habitats that play an essential role in regional flood protection, resiliency, and ecological connectivity. Flooding and habitat loss have long challenged the Lower Darby Creek Area, particularly in the communities of Eastwick in southwest Philadelphia and Tinicum Township of Delaware County, PA. Residents in these neighborhoods experience extreme flooding during storm and high tide events, and community groups have been leading local efforts to enhance resilience and reduce flood risk. The increasing effects of climate change, such as more intense storms, sea level rise, and frequent tidal flooding, are compounding challenges. To help address these challenges, The Nature Conservancy in Pennsylvania (TNC) and the John Heinz National Wildlife Refuge have commissioned Princeton Hydro to lead a two-year Urban Flood and Habitat Resilience Feasibility Study for the Lower Darby Creek Area. The study aims to identify and evaluate nature-based solutions that would help to convey, store, and infiltrate water to alleviate flooding, improve habitat for local wildlife species, and enhance community resilience. For this feasibility study, Princeton Hydro is combining field data collection, hydrologic and hydraulic modeling, and alternatives analysis to determine the most effective nature-based solutions that benefit both nature and people. These may include wetland creation or enhancement, stream and floodplain reconnection, and stormwater management retrofits designed to restore natural hydrologic function. Community engagement is a cornerstone of the Feasibility Study, ensuring that local voices help shape the region’s path toward long-term resilience. The project work began with a series of community meetings to learn from residents about the impacts of flooding and the changes they want to see in their neighborhoods. The outcome of this project will be a list of 6-10 nature-based solutions that have been prioritized by community members and that have been analyzed for feasibility and potential for flood reduction and ecological benefit. This information will be presented in a Project Roadmap for the co-developed pathway to achieve community and ecological resilience through project implementation. This guidance will empower partners and communities to secure funding, implement pilot projects, and advance long-term resilience goals. Once the study is complete, Princeton Hydro will create an interactive ArcGIS StoryMap webpage that will allow users to take a deeper dive into the study's findings and interact with the data. Users will be able to visualize flood scenarios and potential restoration opportunities and learn more about specific project activities and the proposed solutions. Community Engagement in Action: Eastwick Community Day Earlier this year, project partners joined residents for Eastwick Community Day, a vibrant event celebrating neighborhood connections, local leadership, and climate resilience. Hosted by the City of Philadelphia’s Office of Sustainability, the event was supported by representatives from The Nature Conservancy in Pennsylvania, John Heinz National Wildlife Refuge, and Princeton Hydro, including Director of Restoration & Resilience Christiana Pollack, CERP, CFM, GISP and Director of Aquatics Mike Hartshorne. The gathering offered residents an opportunity to meet the organizations involved in the flood study, learn about available climate resilience resources, and share their own experiences and priorities. Alongside informational displays and project updates, attendees enjoyed a picnic lunch, family activities, and hands-on learning about nature-based solutions. It was a day that captured the spirit of collaboration driving this initiative. Check out some highlights from the day, captured by Kim Hachadoorian, Stream Stewards Project Manager for The Nature Conservancy: [gallery columns="2" link="none" ids="17637,17638,17631,17635"] Building on the Eastwick Flood Resilience Study The Lower Darby Creek initiative builds on Princeton Hydro’s earlier Eastwick Flood Resilience Study, expanding from a neighborhood-focused analysis to a watershed-scale approach. In 2016, in partnership with the University of Pennsylvania, the John Heinz National Wildlife Refuge, Keystone Conservation Trust, Audubon Pennsylvania, and the William Penn Foundation, Princeton Hydro conducted an analysis of Eastwick, the flood impacts created by the Lower Darby Creek, and the viability of several potential flood mitigation strategies. The study sought to answer questions commonly asked by community members related to flooding conditions, with the main question being: What impact does the landfill have on area flooding? Princeton Hydro developed a 2-D hydrologic and hydraulic model to understand how varying restoration techniques, including removal of the Clearview Landfill, expansion of the existing tidal freshwater wetland, removal of bridge infrastructure, and rerouting storm flows, would alter flooding in the Eastwick neighborhood. Findings from that study provided key data and analytical frameworks that now inform the Lower Darby Creek Area Feasibility Study. Expanding beyond the boundaries of Eastwick, the comprehensive Lower Darby Creek Area study takes a watershed-scale view, exploring how interconnected systems, including upstream hydrology, tidal influences, and habitat networks, can be managed holistically. [caption id="attachment_7896" align="aligncenter" width="751"] Princeton Hydro developed a 2-dimensional hydrologic and hydraulic model to understand how varying restoration techniques would alter flooding in the Eastwick neighborhood.[/caption] Partnerships for a Resilient Future Resilience is not achieved in isolation; it thrives through collaboration. The success of the Lower Darby Creek Area Feasibility Study and related restoration projects depends on a network of partners committed to shared goals. By aligning expertise, resources, and local knowledge, these partnerships create a foundation for long-term climate adaptation and ecological health. To learn more about the Nature Conservancy in Pennsylvania, click here. To learn more about the City of Philadelphia Office of Sustainability Flood Resilience Strategy for Eastwick, go here. And, click here to learn more about the John Heinz National Wildlife Refuge in Tinicum. Princeton Hydro is also collaborating with the Refuge to restore the Refuge’s Turkey Foot area. Working with Enviroscapes and Merestone Consultants, our team designed and implemented habitat enhancement and hydrologic restoration projects to improve water quality, restore native wetland vegetation, and expand habitat for fish and wildlife. If you’re interested in learning more about this project, check out our blog: Ecological Restoration in John Heinz National Wildlife Refuge. [post_title] => Building Resilience: Exploring Nature-Based Solutions in Lower Darby Creek [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => building-resilience-exploring-nature-based-solutions-in-lower-darby-creek [to_ping] => [pinged] => [post_modified] => 2025-12-10 15:03:38 [post_modified_gmt] => 2025-12-10 15:03:38 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=18641 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 18278 [post_author] => 1 [post_date] => 2025-10-15 11:12:53 [post_date_gmt] => 2025-10-15 11:12:53 [post_content] => 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. [caption id="attachment_18273" align="aligncenter" width="1227"] Jackson and Jesse preparing to deploy sampling collection gear in Brooklyn Bridge Park.[/caption] [gallery columns="2" link="none" size="medium" ids="18274,18267"] 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. More Scenes from the Field 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: [gallery link="none" size="medium" ids="18276,18271,18277,18272,18269,18284"] *The Asian Shore Crab pictured above is an invasive species encountered fairly often during the Summer sampling events. [caption id="attachment_18266" align="aligncenter" width="1227"] Dogfish (Squalus acanthias)[/caption] 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. [post_title] => Partnering with Billion Oyster Project to Study Urban Reef Ecosystems [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => partnering-with-billion-oyster-project-to-study-urban-reef-ecosystems [to_ping] => [pinged] => [post_modified] => 2025-10-15 14:45:17 [post_modified_gmt] => 2025-10-15 14:45:17 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=18278 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [3] => WP_Post Object ( [ID] => 18294 [post_author] => 1 [post_date] => 2025-10-13 18:11:03 [post_date_gmt] => 2025-10-13 18:11:03 [post_content] => 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. Inside the Workshop 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. [gallery link="none" columns="2" size="medium" ids="18298,18297" orderby="rand"] 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. More About Coastal Restoration 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. Key restoration activities include:
Friends of Hopewell Valley Open Space (FoHVOS), in partnership with Princeton Hydro, has launched a groundbreaking initiative, “Monitoring Harmful Algal Blooms (HABs) in the Delaware River Watershed Using Drones and Spatial Analysis,” to improve understanding and forecasting of HABs throughout the Delaware River Watershed. Funded by the National Fish and Wildlife Foundation (NFWF), in partnership with the U.S. Fish & Wildlife Service, through the Delaware Watershed Conservation Fund (DWCF), 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.
For this innovative research project, FoHVOS, a 501(c)3 and accredited Land Trust located in Hopewell Township, NJ, has teamed with Princeton Hydro. Princeton Hydro conceptualized and designed the initiative and is leading the technical implementation, including field survey design, drone operations, data analysis, and volunteer training.
“The Delaware River is central to Hopewell Valley’s identity. It shapes our way of life, supplies drinking water to 14.2 million people, shelters wildlife like the endangered Atlantic sturgeon, and offers abundant outdoor recreation,” said Jennifer Rogers, Executive Director of FoHVOS. “HABs were once confined to ponds and lakes, but since 2018, they’ve appeared in colder months and spread to streams and rivers. Though land trusts traditionally focus on land, HABs show how land use directly affects water. These blooms often stem from excess nitrogen and phosphorus washed into waterways during storms. Protecting water means restoring land. Our partnership with Princeton Hydro aligns perfectly with our mission. Together, we’re working to better understand and safeguard the Delaware River and its tributaries in both NJ and PA.”
HABs, caused by nuisance growth of cyanobacteria, can have detrimental effects on water quality and are a growing environmental concern nationwide. These blooms deplete oxygen levels, release toxins, and disrupt ecosystems, potentially posing serious risks to drinking water supplies and the health of wildlife, pets, humans, and local economies. Despite advances in environmental monitoring, predicting when and where HABs will occur remains a challenge due to the complex interplay of nutrient loading, temperature, and hydrologic conditions that can lead to rapid bloom proliferation.
To address these challenges, this newly launched initiative integrates drone-based remote sensing, field sampling, and spatial data analysis to collect and interpret detailed environmental data over a two-year period. The study spans multiple monitoring sites along a 73-mile stretch of the Delaware River in New Jersey and Pennsylvania, focusing on near-shore sections and 23 associated waterbodies. The first survey event began in August 2025.
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.
The following photos depict the RGB (Visual) and corresponding Thermal image from the monitoring flights over Spring Lake in New Jersey:
“This research project represents a major step forward in how we study and manage harmful algal blooms at the watershed scale,” said Dr. Fred Lubnow, Project Lead and Senior Technical Director of Ecological Services at Princeton Hydro. “By integrating satellite data, drone imagery, and on-the-water sampling, we’re developing predictive tools that will enable us take a proactive approach to mitigate HABs, improve response time, and better support our ecosystem health.”
Project partners include New York City College of Technology – The City University of New York, which donated the drone and is supporting remote sensing and data integration; Trenton Water Works, Mercer County Park Commission, and The College of New Jersey which are providing monitoring sites and contributing volunteers for water quality data collection in New Jersey; Aqua-PA and the Philadelphia Water Department, which are providing monitoring sites and volunteers to collect watershed data in Pennsylvania; the Bucks County Conservation District, which is coordinating volunteer data collection; and Turner Designs, whose advanced phycocyanin sensors are being used to calibrate and validate drone-based monitoring data.
In the photos below, volunteers are being trained by Princeton Hydro staff on how to use phycocyanin fluorometers and Secchi disks to gather water quality data and log their findings.
This $1M project is funded through a $488,400 NFWF DWCF grant as part of the NFWF’s Research, Monitoring, & Evaluation Grant category and $513,700 in matching funds from project partners. This grant category aims to support high-performing science that is inclusive, adaptive, and innovative, with the potential to transform the Delaware River Watershed’s future through improved conservation, restoration, and public engagement.
Once complete, the project will produce a comprehensive report summarizing methods, analyses, and data-driven recommendations for practical, low-cost HAB monitoring and mitigation strategies that can be replicated across the Delaware River Watershed and beyond. Crucially, the report will identify tributaries and sources contributing to riverine HABs, enabling targeted restoration of the most affected lands and waters. Data collection will continue through Fall 2025, resume in Spring/Summer 2026, and culminate in a final report expected in 2027.
FoHVOS is a 501(c)3 nonprofit land trust dedicated to conserving the natural resources of the Hopewell Valley region and beyond. Through land preservation, ecological restoration, community engagement, and science-driven initiatives, FoHVOS works to protect and enhance open spaces for future generations. Learn more at www.fohvos.org.
Princeton Hydro is committed to improving our ecosystems, quality of life, and communities for the better. The firm was formed in 1998 with the specific mission of providing integrated ecological and engineering consulting services. Offering expertise in natural resource management, water resources engineering, geotechnical design and investigation, and regulatory compliance, their staff provide a full suite of environmental services throughout the Northeast for the public and private sectors. Project Lead, Dr. Fred Lubnow, is an expert in HAB management and has worked with dozens of lake associations and government agencies to restore lakes, manage watersheds, reduce pollutant loading, address invasive aquatic plants, and mitigate nuisance HABs. To learn more about Princeton Hydro's work to mitigate harmful algal blooms, go here.
The Lower Darby Creek Area encompasses a unique blend of residential neighborhoods, commercial zones, and critical regional infrastructure, including the Philadelphia International Airport, Interstate 95, and portions of the John Heinz National Wildlife Refuge. Despite its urban setting, the area supports diverse wetlands, waterways, and wildlife habitats that play an essential role in regional flood protection, resiliency, and ecological connectivity.
Flooding and habitat loss have long challenged the Lower Darby Creek Area, particularly in the communities of Eastwick in southwest Philadelphia and Tinicum Township of Delaware County, PA. Residents in these neighborhoods experience extreme flooding during storm and high tide events, and community groups have been leading local efforts to enhance resilience and reduce flood risk. The increasing effects of climate change, such as more intense storms, sea level rise, and frequent tidal flooding, are compounding challenges.
To help address these challenges, The Nature Conservancy in Pennsylvania (TNC) and the John Heinz National Wildlife Refuge have commissioned Princeton Hydro to lead a two-year Urban Flood and Habitat Resilience Feasibility Study for the Lower Darby Creek Area. The study aims to identify and evaluate nature-based solutions that would help to convey, store, and infiltrate water to alleviate flooding, improve habitat for local wildlife species, and enhance community resilience.
Community engagement is a cornerstone of the Feasibility Study, ensuring that local voices help shape the region’s path toward long-term resilience. The project work began with a series of community meetings to learn from residents about the impacts of flooding and the changes they want to see in their neighborhoods. The outcome of this project will be a list of 6-10 nature-based solutions that have been prioritized by community members and that have been analyzed for feasibility and potential for flood reduction and ecological benefit. This information will be presented in a Project Roadmap for the co-developed pathway to achieve community and ecological resilience through project implementation. This guidance will empower partners and communities to secure funding, implement pilot projects, and advance long-term resilience goals.
Once the study is complete, Princeton Hydro will create an interactive ArcGIS StoryMap webpage that will allow users to take a deeper dive into the study's findings and interact with the data. Users will be able to visualize flood scenarios and potential restoration opportunities and learn more about specific project activities and the proposed solutions.
Earlier this year, project partners joined residents for Eastwick Community Day, a vibrant event celebrating neighborhood connections, local leadership, and climate resilience. Hosted by the City of Philadelphia’s Office of Sustainability, the event was supported by representatives from The Nature Conservancy in Pennsylvania, John Heinz National Wildlife Refuge, and Princeton Hydro, including Director of Restoration & Resilience Christiana Pollack, CERP, CFM, GISP and Director of Aquatics Mike Hartshorne.
The gathering offered residents an opportunity to meet the organizations involved in the flood study, learn about available climate resilience resources, and share their own experiences and priorities. Alongside informational displays and project updates, attendees enjoyed a picnic lunch, family activities, and hands-on learning about nature-based solutions. It was a day that captured the spirit of collaboration driving this initiative.
The Lower Darby Creek initiative builds on Princeton Hydro’s earlier Eastwick Flood Resilience Study, expanding from a neighborhood-focused analysis to a watershed-scale approach. In 2016, in partnership with the University of Pennsylvania, the John Heinz National Wildlife Refuge, Keystone Conservation Trust, Audubon Pennsylvania, and the William Penn Foundation, Princeton Hydro conducted an analysis of Eastwick, the flood impacts created by the Lower Darby Creek, and the viability of several potential flood mitigation strategies. The study sought to answer questions commonly asked by community members related to flooding conditions, with the main question being: What impact does the landfill have on area flooding? Princeton Hydro developed a 2-D hydrologic and hydraulic model to understand how varying restoration techniques, including removal of the Clearview Landfill, expansion of the existing tidal freshwater wetland, removal of bridge infrastructure, and rerouting storm flows, would alter flooding in the Eastwick neighborhood.
Findings from that study provided key data and analytical frameworks that now inform the Lower Darby Creek Area Feasibility Study. Expanding beyond the boundaries of Eastwick, the comprehensive Lower Darby Creek Area study takes a watershed-scale view, exploring how interconnected systems, including upstream hydrology, tidal influences, and habitat networks, can be managed holistically.
Resilience is not achieved in isolation; it thrives through collaboration. The success of the Lower Darby Creek Area Feasibility Study and related restoration projects depends on a network of partners committed to shared goals. By aligning expertise, resources, and local knowledge, these partnerships create a foundation for long-term climate adaptation and ecological health. To learn more about the Nature Conservancy in Pennsylvania, click here. To learn more about the City of Philadelphia Office of Sustainability Flood Resilience Strategy for Eastwick, go here. And, click here to learn more about the John Heinz National Wildlife Refuge in Tinicum.
Princeton Hydro is also collaborating with the Refuge to restore the Refuge’s Turkey Foot area. Working with Enviroscapes and Merestone Consultants, our team designed and implemented habitat enhancement and hydrologic restoration projects to improve water quality, restore native wetland vegetation, and expand habitat for fish and wildlife. If you’re interested in learning more about this project, check out our blog: Ecological Restoration in John Heinz National Wildlife Refuge.
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.
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.
Nestled in Luzerne County, Pennsylvania, Harveys Lake spans 622 acres and is the largest natural lake by volume in the Commonwealth. Beyond its scenic beauty and popularity as a recreational destination, the lake plays a critical ecological role in the region.
Harveys Lake forms the headwaters of Harveys Creek, which flows into the Susquehanna River and ultimately the Chesapeake Bay. As such, it is part of the greater Susquehanna River Valley and contributes to the health of the Chesapeake Bay watershed. The lake and its outflow are designated High Quality – Cold-Water Fisheries, supporting sensitive aquatic life, providing vital cold-water habitat, and contributing to regional biodiversity.
Given its ecological significance and its connection to regional waterways, efforts to manage stormwater and reduce nutrient pollution in the Harveys Lake watershed are more than just local improvements, they are integral to protecting downstream water quality all the way to the Chesapeake Bay.
In 2022, building on decades of water quality initiatives, the Borough of Harveys Lake launched a forward-thinking pilot project to enhance stormwater treatment using innovative nutrient-filtering technologies. Supported by funding from the National Fish and Wildlife Foundation (NFWF) Chesapeake Bay Small Watershed Grant Program and designed and implemented in partnership with Princeton Hydro, this project explores the use of biochar and EutroSORB® filtration media to capture dissolved nutrients, an important step toward improving water quality and meeting regulatory goals.
This blog explores the local history of water management at Harveys Lake, the science behind this novel pilot approach, and the broader implications for watershed protection across the region.
Once a remote, wooded landscape, the Harveys Lake area was settled in the early 19th century and gradually developed into a hub for timbering and milling. By the late 1800s, the lake was regularly stocked with game fish, and with the arrival of the railroad in 1887, it quickly became a popular summer destination. The shoreline soon featured hotels, restaurants, and even an amusement park.
As the community flourished, the lake's natural systems began to show signs of strain. Like many waterbodies across the country, Harveys Lake faced growing water quality challenges driven by stormwater runoff, nutrient pollution, and a lack of formal environmental protections. By the 1960s, declining water clarity and seasonal algal blooms began to impact recreation, contributing to the lake’s gradual transition from a bustling public getaway to a primarily residential community.
A significant shift occurred following the passage of the U.S. Environmental Protection Agency’s Clean Water Act of 1972. Harveys Lake established a municipal sewer authority, and construction began on a utility line around the lake's perimeter to reduce point-source pollution. Still, algae blooms persisted throughout the 1980s, fueled by nonpoint sources such as stormwater runoff, lawn fertilizers, and waterfowl droppings.
In 1994, a Phase I Diagnostic Feasibility Study was conducted that formally identified Harveys Lake as impaired due to recurring algal blooms linked to elevated nutrient levels. Following this study, a Total Maximum Daily Load (TMDL) was established, and management efforts were initiated to meet long-term water quality goals.
Since 2003, the Harveys Lake watershed has undergone extensive stormwater management efforts, including the installation of numerous manufactured treatment devices (MTDs) to reduce pollutant loading. Most of these MTDs are nutrient separating baffle boxes (NSBBs), chosen due to the watershed’s steep slopes, dense residential development, and shallow bedrock. The first NSBB, pictured below, was installed at Hemlock Gardens:
In 2009, the Borough of Harvey’s Lake worked with Princeton Hydro to develop a Stormwater Implementation Plan that laid the foundation for future restoration efforts. Over the following years, the Borough of Harveys Lake, supported by state and regional grants, implemented 34 stormwater best management practices (BMPs) and installed four floating wetland islands throughout the watershed.
These projects were strategically designed to reduce nutrient loading, enhance water quality, and move the lake closer to achieving its TMDL targets. Click here to read more about these efforts.
While NSBB stormwater BMPs are highly effective at capturing sediments and associated pollutants, they are limited in their ability to remove dissolved nutrients, particularly nitrogen and phosphorus. This is evident in the Harveys Lake Watershed, where NSBBs remove approximately 70% of total suspended solids (such as sediment and plant debris), 35% of total phosphorus, and 0% of total nitrogen. To address this gap and improve overall nutrient removal efficiency, the Borough of Harveys Lake received funding from the NFWF Chesapeake Bay Small Watershed Grant Program to augment existing MTD stormwater BMPs using new filter technologies.
Partnered with Princeton Hydro for design, implementation, and technical support, the Borough launched a unique pilot project involving the installation of biochar and EutroSORB® (manufactured by SePRO Corporation) to evaluate the effectiveness of these two innovative materials in removing dissolved phosphorus and total nitrogen from stormwater runoff before it reaches Harveys Lake.
Biochar, a carbon-rich material derived from plant biomass, is valued for its high surface area and nutrient-adsorption capacity. EutroSORB® is a manufactured media specifically engineered to bind and retain dissolved phosphorus with demonstrated effectiveness in aquatic systems.
Filter socks filled with either biochar or EutroSORB® were installed at key stormwater outfalls and stream inlets that drain directly to the lake. At four NSBB sites, the socks were secured beneath manhole covers using a rope-and-carabiner system designed for easy, seasonal replacement. Each sock weighs approximately 50–60 pounds when saturated and was carefully positioned to avoid dislodgement or blockage of outlet pipes during high-flow events.
At the Hemlock Gardens site, which features a larger, multi-tray baffle box, twelve filter socks were installed across two horizontal trays to maximize contact time between stormwater and the filter media.
By integrating these innovative filter techniques into the existing BMP infrastructure, the Borough of Harveys Lake is taking a proactive, science-based approach to nutrient reduction and long-term water quality improvement.
Princeton Hydro implemented a comprehensive water quality monitoring program in the Harveys Lake watershed to assess the real-world performance of the biochar and EutroSORB® filtration systems under varying hydrologic conditions, with a particular focus on dissolved nutrients that contribute to eutrophication.
Six stormwater monitoring stations were established at locations where biochar or EutroSORB® were deployed within NSBBs or stream inlets. Each site included paired upstream (pre-treatment) and downstream (post-treatment) sampling points to capture the nutrient concentrations entering and exiting the filtration media.
Stormwater sampling was conducted during six separate rainfall events between March and April 2025. At each location, during storm flow conditions, discrete grab samples were collected via a portable polyethylene sampling pole and analyzed for key water quality parameters.
Beyond concentration-based comparisons, Princeton Hydro used empirical monitoring data to model pollutant loads upgradient and downgradient of the filtration media. These load estimates provide insights into pollutant removal effectiveness on a mass basis, with a focus on:
Emphasis was placed on SRP—the biologically available form of phosphorus most readily assimilated by algae and a key driver of harmful algal blooms and eutrophication. Because phosphorus is the target pollutant in Harveys Lake’s TMDL, SRP reduction serves as a critical indicator of the filtration media’s performance and its potential role in long-term water quality management strategies.
Overall, the study revealed variable but promising results across media types and installation locations:
These early findings suggest that both EutroSORB® and biochar hold promise as cost-effective tools for reducing soluble phosphorus in stormwater runoff. Additionally, observed differences in removal efficiency, based on installation context (NSBB vs. stream), filter media volume, and site-specific hydrologic conditions, underscore the importance of continued monitoring and system refinement.
As part of the project’s commitment to long-term sustainability and public education, a native pollinator garden was established near the Harveys Lake Department of Public Works garage, adjacent to the Little League fields.
After the final sampling in April 2025, the nutrient-saturated biochar and EutroSORB® socks were removed from the stormwater treatment systems. The spent biochar, having captured phosphorus and nitrogen from runoff, was repurposed as a soil amendment to enrich a 500-square-foot planting area. 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.
The Harveys Lake Environmental Advisory Council volunteered to help plant the garden, installing 450 native plant plugs across nine species including Foxglove Beardtongue, Clustered Mountain Mint, Blue Wild Indigo, and Common Yarrow to attract pollinators such as butterflies, bees, and songbirds.
Designed by Princeton Hydro, the pollinator garden serves as both an ecological asset and an educational tool. Its prominent location next to the ballfields encourages community engagement, and an interpretive sign on-site helps visitors understand the garden’s purpose and its connection to local water quality initiatives. The sign features a QR code linking to an interactive ArcGIS StoryMap, developed by Princeton Hydro, which explores the broader context of the project. It draws connections between nutrient management efforts in Harveys Lake and similar challenges facing the entire Chesapeake Bay watershed, emphasizing how local actions contribute to regional water quality improvements. To support public outreach, the StoryMap was also shared on the Borough’s website, making this educational resource widely accessible to the community.
It is important to note that while this project illustrates a successful example of biochar reuse, all reuse applications must be assessed on a case-by-case basis. For example, biochar exposed to hazardous pollutants is not suitable for soil use. In this case, the biochar had only been used to absorb excess nutrients, making it appropriate for the garden setting.
Supported by the U.S. Environmental Protection Agency and the NFWF’s Chesapeake Bay Stewardship Fund, which promotes community-based conservation strategies to protect and restore Chesapeake Bay’s natural resources, this project was designed with scalability in mind. A core objective was to evaluate whether these filtration media could be more broadly implemented throughout the Chesapeake Bay watershed as a low-cost, community-integrated strategy for achieving water quality goals.
Through continued innovation and shared learning, small-scale efforts like this can drive large-scale impact, proving that effective water quality solutions don’t have to be costly or complex. The Harveys Lake model offers a replicable framework that communities across the region can adopt and adapt, empowering local action that contributes meaningfully to the restoration and resilience of Chesapeake Bay.
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, 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.
“It was a fun chance to unplug, get our hands in the dirt, and connect with coworkers in a different kind of ‘team meeting,’” said Mikhail Velez, Communications Coordinator. “It’ll be exciting to see how the space fills in over the season, and we’re looking forward to doing small things throughout the year to keep it healthy and thriving.”
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.
On April 12, 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.
When we made the decision to move Princeton Hydro’s headquarters to Trenton in April of 2022, we knew we were becoming part of something special. It wasn’t just about finding a new office—it was about joining a community with a rich history, vibrant culture, and a shared dedication to environmental and social progress. From the very beginning, we felt a sense of belonging and purpose here. Trenton isn’t just where we work; it’s where we’ve had the chance to grow, learn, and give back to a place that inspires us every day.
From its founding by Dr. Fred Lubnow, original and former President, Dr. Stephen J. Souza (retired), and us, our firm has always been guided by a philosophy of stewardship, sustainability, and community partnership. While our core work focuses on ecological and engineering consulting, we firmly believe that our responsibility extends beyond the projects we undertake, focusing on fostering genuine partnerships and creating lasting impacts in the communities we serve. In Trenton, we've been especially fortunate to experience the powerful connection that comes from working alongside local organizations and residents.
Since relocating our headquarters to Trenton, we’ve been honored to open our doors and our hearts to a wide range of local organizations and causes. By hosting events for nonprofit groups like Greater Trenton, Outdoor Equity Alliance, NJ Society of Women Environmental Professionals, Boys and Girls Club of Mercer County, Revolutionary Trenton, Princeton-Mercer Regional Chamber, and many others, we’ve had the privilege of supporting efforts that protect both the environment and the cultural heritage of Trenton. These events are more than gatherings; they are moments that strengthen community bonds and foster a sense of connection that is vital to the city’s growth and vibrancy.
In that spirit, we are proud to contribute to local causes that directly uplift Trenton’s residents. Whether organizing coat drives for the Children’s Home Society of NJ, running food drives for Arm & Arm, or sponsoring local events like Juneteenth, the Black Farmers Market, Jersey Fresh Jam, and the Summer Splash Bash, we are constantly inspired by the resilience and commitment of the people in this city. These initiatives allow us to give back to a community that has given us so much, while also fostering environmental awareness and celebrating the rich cultural and communal life that makes Trenton so special.
Our focus on STEAM (Science, Technology, Engineering, Arts, and Math) education is another way we aim to make a lasting impact. We are honored to support programs like the Hold High the Torch’s Eco Innovators for Youth STEAM Leaders, the Outdoor Equity Alliance’s Careers in Conservation, and the NJ Department of Environmental Protection’s Youth Inclusion Initiative, which are essential for nurturing the next generation of environmental leaders. By helping students engage with real-world environmental challenges, we hope to inspire future conservationists and scientists who will carry forward the work we’ve begun.
In addition to our community outreach, we have been directly involved in significant environmental projects throughout Trenton. Our partnership with Trenton Water Works on the water quality sampling at Pennington Reservoir has been crucial in ensuring safe and reliable water for the city. We collaborated with the Trenton South Ward Neighborhood Association on a Community Garden and Park Visioning project, assisting them in securing a grant that resulted in the planting of 500 native plants, enhancing public spaces and creating a habitat for monarch butterflies. One of our most impactful efforts has been the Abbott Marshlands wetland restoration project at John A. Roebling Park, in collaboration with the Mercer County Park Commission, to eradicate invasive species and bring back the native landscape for park goers to enjoy. These projects demonstrate our commitment to restoring greater Trenton’s natural habitats, creating a sustainable future for its ecosystems, and leaving a positive, tangible mark on the city’s landscape.
As we reflect on our work in the Trenton region, we are truly humbled by the recognition we’ve received. In 2023, Princeton Hydro was honored with the New Good Neighbor Award by the NJBIA, a testament to our commitment to being more than just a business operating in Trenton, but a dedicated partner in its success. Additionally, our office itself was recognized with a Historic Preservation Award from Preservation New Jersey, underscoring the importance we place on respecting and preserving the rich history of the City while looking toward the future.
At Princeton Hydro, we are committed to being not just a business in Trenton, but a dedicated partner in its success. We take pride in the contributions we’ve made thus far, yet we recognize that our journey is far from complete. With the community's support and collaboration, we believe we can continue to make a meaningful, lasting impact as we work together toward a sustainable future – one that enriches our environment and enhances the quality of life for everyone.
New Jersey Department of Environmental Protection (NJDEP) 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 Firehouse, celebrated the Lambertville's commitment to improving stormwater management, addressing flooding, protecting local waterbodies, increasing storm resilience, and mitigating the impacts of climate change.
In a press release announcing the award, Commissioner LaTourette said, “Modernization of stormwater management strategies and infrastructure is critical to mitigating flooding that is severely impacting communities across New Jersey. My DEP colleagues and I applaud Lambertville for paving the way for others to follow in managing stormwater more effectively.”
The "Our Water’s Worth It" campaign, launched by NJDEP earlier this year, aims to raise awareness about the importance of protecting New Jersey’s water resources. The campaign highlights municipalities, water systems, and others who go above and beyond in water resource management and infrastructure improvements. Lambertville’s forward-thinking approach to stormwater management, particularly in meeting permitting requirements ahead of schedule, earned the city this well-deserved recognition.
At Princeton Hydro, we are proud to support the City of Lambertville in its stormwater management initiatives. Our team has been working closely with Lambertville to design projects that not only mitigate flooding but also enhance the surrounding natural environment.
During the award ceremony, Senior Project Manager and Professional Engineer, Sean Walsh, PE, said: “We are honored to be here today alongside NJDEP and the City of Lambertville celebrating Lambertville's remarkable achievement in receiving the 'Our Water's Worth It' trophy. It's particularly meaningful that this recognition comes during Climate Week, underscoring the importance of local action in addressing global environmental challenges.”
Earlier this year, the Princeton Hydro team completed a comprehensive Stormwater Utility Feasibility Study, which provided critical insights into Lambertville’s current stormwater management capacity and forecasted future needs.
Among the ongoing projects, Princeton Hydro is evaluating solutions for capturing runoff and reducing flooding in Lambertville's Music Mountain area, a critical greenspace in the heart of the city. This steep, wooded hillside, home to popular nature trails, serves as a cherished spot for after-school exploration, dog walking, and outdoor recreation. Music Mountain also plays a critical role in the city’s stormwater management system, acting as a natural buffer to protect lower-lying areas from flash flooding caused by runoff from the residential neighborhoods above. However, storm sewer outfalls discharging into the hillside have created deep erosion gullies, and during heavy rain events, the runoff has flooded the Fire Department. In collaboration with the City and the Fire Department, Princeton Hydro is designing a comprehensive solution that includes both the installation of a piped stormwater system and enlarging the inlet at the base of the mountain to better capture surface water runoff.
Additionally, on the Closson Farm property, Princeton Hydro is designing a riparian restoration project to manage the effects of increasing storm intensity. Funded by the National Fish and Wildlife Foundation, this project will result in 4.6 acres of restored floodplain, 300 trees planted, creation of wildlife habitat, measurable sediment and nutrient reduction, reduced stormwater runoff, community engagement, and new walking paths for recreation.
“Together with Lambertville, we are taking essential steps to enhance the city’s infrastructure and safeguard the community against future flooding. Our partnership reflects a shared commitment to protecting the environment and promoting resilience,” said Princeton Hydro’s Director of Restoration & Resilience, Christiana Pollack, CFM, GISP.
By embracing innovative stormwater solutions, Lambertville is not only enhancing its infrastructure but also setting a benchmark for resilience and environmental stewardship across New Jersey. This recognition reflects the city’s commitment to proactive flood management and sustainability, serving as an inspiration for other communities.
Princeton Hydro is honored to partner with the City of Lambertville on these important efforts. We extend our heartfelt congratulations on this well-deserved recognition and are excited to continue our collaboration on future projects that will further strengthen the city's resilience and protect its vibrant neighborhoods.
To learn more about NJDEP’s "Our Water’s Worth It" campaign, watch the video below:
New Jersey’s water-related infrastructure is a complex system, constantly facing the challenges posed by stormwater runoff and working to properly manage it. Stormwater management isn’t just about handling rainfall; it’s a critical aspect of improving water quality and mitigating flood risks. In New Jersey, where urbanization and rainfall patterns intersect, managing stormwater is more than just a priority; it’s a necessity. To learn more about stormwater management solutions, check out our blog: "In the Eye of the Storm: Exploring A Stormwater Utility in New Jersey."
Could cows be a potential solution to climate change?
Livestock contributes significantly to climate change, with estimates ranging from 11.1% to almost 20% of global greenhouse gas emissions. This is primarily due to their methane-rich belches and flatulence. Given these substantial numbers, it may seem unlikely that cows could be part of the solution. However, Arizona State University Professor Peter Byck argues that cows themselves are not the problem but rather the manner in which they are managed and raised.
Progressive farmers can enhance soil health and increase carbon sequestration through a cattle grazing technique known as Adaptive Multi-Paddock (AMP) grazing. This practice, entailing the periodic movement of cattle between various land plots, facilitates the creation of carbon sinks by ranchers utilizing their herds. It mimics the historical grazing patterns of bison on the expansive U.S. plains, incorporating extended rest periods between grazing events to allow grass to flourish, thereby enriching the soil. Please note however, despite anecdotal evidence from scientists and farmers, comprehensive research to validate these assertions is lacking.
The extent to which traditional grazing farmers will adopt this innovative solution remains an open question. For several years, Peter Byck has dedicated himself to meeting with scientists and farmers. This journey has culminated in the creation of a four-part docuseries titled "Roots So Deep (You Can See the Devil Down There)." This docuseries chronicles Peter Byck's experiences and the knowledge he gained along the way.
The documentary features Princeton Hydro's Senior Wildlife Biologist, Michael McGraw, CSE, QAWB, and ACE. He is part of a multidisciplinary team of scientists whose research forms the basis of the documentary.
Michael's studies have focused on observing the dynamics of breeding bird populations in paddocks grazed by AMP and those continuously grazed. The documentary highlights that when managed effectively, farmland can boost productivity and profitability for farmers while simultaneously contributing positively to the environment and the diverse wildlife that shares the planet with humans.
During a screening of "Roots So Deep (You Can See the Devil Down There)," Michael discusses his deep emotional connection formed through a decade-long collaboration with scientists and farmers. This partnership aimed to explore new opportunities to enhance our soils, wildlife, and communities. He bestows upon the audience a powerful message: “It doesn’t matter if you believe in climate change because, at the end of the day, we’re supporting healthy American families and promoting biodiversity, which benefits us all.”
In this clip, Peter and Michael explore how individuals from diverse backgrounds and beliefs can find common ground in unexpected places. They discuss how environmental stewardship unites people, revealing shared values that transcend differences and inspire collective action towards a sustainable future.
The complete docuseries is now available for rent. Learn more and watch the series at rootssodeep.org. To learn more about Senior Wildlife Biologist, Michael McGraw, a CSE, QAWB, and ACE, click here.
As we reflect on the winter of 2023-2024, it's evident that New Jersey experienced another unusually mild season, mirroring the winter of 2022-2023. Notably, Lake Hopatcong, located in Sussex and Morris Counties, remained virtually ice-free throughout the winter, with only a brief period of minor ice formation in early January. This pattern was not isolated to Lake Hopatcong; many lakes across the state and the broader Mid-Atlantic region exhibited similar ice-free conditions. Such conditions can lead to increased algal and plant growth earlier in the year.
Adding to this, from January to early June 2024, 15 of New Jersey's 21 counties recorded precipitation levels 26% to 50% higher than their long-term averages. The remaining six counties, predominantly in the southern part of the state, had precipitation increases of 11% to 25% above their long-term normals. This heightened precipitation is significant as it can transport nutrients, most notably phosphorus and nitrogen, into water bodies, potentially fueling the growth of algae.
Compounding these factors, long-range climate models and trends suggest that the summer of 2024 could rank among the hottest on record. The combination of a mild winter, increased precipitation, and anticipated high summer temperatures sets the stage for conditions similar to those experienced in 2019, a year marked by widespread harmful algal blooms (HABs) in numerous lakes.
HABs, characterized by rapid overgrowths of cyanobacteria, present serious challenges to water quality and aquatic ecosystems. Cyanobacteria, or blue-green algae, naturally occur in aquatic environments but can proliferate rapidly under warm, nutrient-rich conditions. These blooms pose risks to human health, wildlife, aquatic species, local economies, and the overall ecological balance. The interplay between climate change and HABs is undeniable: rising temperatures and altered precipitation patterns foster conditions that exacerbate bloom occurrences.
Given these circumstances, it is crucial for lake managers and water utilities to adopt proactive measures. Early and consistent sampling efforts can detect cyanobacteria and akinetes, dormant spores that contribute to bloom formation. Additionally, reducing nutrient inputs, particularly phosphorus, into waterways is essential to prevent HABs. Princeton Hydro strongly recommends that lake managers, water utilities, and concerned community members closely monitor their lakes, reservoirs, and riverways to stay as proactive as possible in managing these valuable resources.
By raising awareness, fostering collaboration, and implementing effective strategies, we can work towards safeguarding the health and sustainability of our freshwater ecosystems. Together, we can address the challenges posed by HABs and protect the integrity of our water bodies. For more information about HABs, click here.
Dr. Fred Lubnow, Princeton Hydro’s Senior Technical Director, Ecological Services, is an expert in aquatic and watershed management, restoration ecology, community and ecosystem ecology, and the use of benthic macroinvertebrate and fish in-stream bioassessment protocols. Dr. Lubnow has managed hundreds of lake projects and provides technical expertise for a variety of lake and watershed restoration projects.
His experience in lake and reservoir restoration includes the design and implementation of dredging, aeration, chemical control of nuisance species, nutrient inactivation (i.e. alum) and biomanipulation. His experience in watershed restoration includes the design and implementation of structural Best Management Practices (BMPs), the development of Total Maximum Daily Load (TMDL) pollutant budgets, and the design, implementation and analysis of watershed-based monitoring programs.
Your Full Name * Phone Number * Your Email * Organization Address Message *
By EmailBy Phone
Submit
Δ
Couldn’t find a match? Check back often as we post new positions throughout the year.
PRINCETON HYDRO
PRINCETON HYDRO