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In that spirit, we’re highlighting a transformative project that turned degraded wetlands into a thriving wildlife sanctuary: The Pin Oak Forest Stream, Wetland, and Upland Enhancement Project in Woodbridge, New Jersey, stands as a testament to the power of restoration and the lasting impact of ecological stewardship. Restoring Vital Habitat in a Developed Landscape Located in a highly developed region of Middlesex County, the Pin Oak Forest Conservation Area is a rare ecological gem—a 97-acre open space containing a critical wetland complex at the headwaters of Woodbridge Creek. Before restoration efforts began, the area suffered from habitat fragmentation, wetland degradation, and the encroachment of invasive species, all of which had significantly reduced biodiversity and threatened native wildlife. Recognizing the urgency of intervention, a diverse coalition of government agencies, NGOs, and private industry, including Middlesex County Office of Parks and Recreation, Woodbridge Township, Woodbridge River Watch, New Jersey Freshwater Wetlands Mitigation Council, GreenTrust Alliance, GreenVest, and Princeton Hydro, came together to design and implement a comprehensive restoration plan aimed at revitalizing the area’s natural functions. The project converted nearly 29 acres of degraded wetlands, over 1,000 feet of channelized streams, and disturbed uplands into a vibrant, species-rich ecosystem. By reconnecting the stream to its floodplain and incorporating microtopography techniques, the restoration team created a varied landscape that supports multiple habitat communities and improves groundwater infiltration—essential elements for sustaining wildlife. [gallery link="none" size="medium" ids="7282,7268,7258"] A Haven for Wildlife The transformation of Pin Oak Forest into a high-functioning wetland complex has had profound impacts. The site now provides critical habitat for a range of species, including the state-threatened Black-crowned Night-Heron (Nycticorax nycticorax) and Red-headed Woodpecker (Melanerpes erythrocephalus). The reestablishment of native vegetation, such as pin oak (Quercus palustris), swamp white oak (Quercus bicolor), and swamp rose (Rosa palustris), has further enhanced the ecosystem, creating food sources and nesting areas for birds, amphibians, and pollinators. [gallery link="none" size="medium" ids="17106,17107,17108"] By managing invasive species and allowing native flora to flourish, biodiversity has significantly increased. The restored headwater wetland system supports a delicate balance of aquatic and terrestrial life, creating a vital refuge for countless species amid an otherwise urbanized landscape. This success story highlights how thoughtful ecological restoration can bring degraded environments back to life, providing a lasting benefit for wildlife and the surrounding community alike. Continuing the Commitment to Wildlife Conservation On this World Wildlife Day, the Pin Oak Forest project serves as an inspiring reminder of what’s possible when partnerships, science, and dedication converge to protect and restore critical habitats. The work done here is not just about the past—it’s about shaping a future where wildlife and people can thrive together. At Princeton Hydro, we remain committed to advancing ecological restoration, ensuring that more landscapes like Pin Oak Forest can be revitalized for generations to come. We hope that by reflecting on the success of this project, more communities and organizations will be inspired to take action in preserving and restoring the natural world and pledge to protect the wildlife that makes our planet so extraordinary. To learn more about the award-winning Pin Oak project and see additional restoration photos, click here. [post_title] => Celebrating World Wildlife Day: A Look Back at the Thriving Habitat of Pin Oak Forest [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => celebrating-world-wildlife-day-a-look-back-at-the-thriving-habitat-of-pin-oak-forest [to_ping] => [pinged] => [post_modified] => 2025-03-03 14:24:52 [post_modified_gmt] => 2025-03-03 14:24:52 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=17105 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 16002 [post_author] => 1 [post_date] => 2025-01-30 20:13:21 [post_date_gmt] => 2025-01-30 20:13:21 [post_content] => An ambitious project is underway to eradicate the invasive Silty Pond Mussel (formerly known as the Chinese pond mussel, Sinanodonta woodiana) from the Wickecheoke Creek Preserve in New Jersey. This critical initiative seeks to protect local ecosystems, safeguard native aquatic species, and prevent the spread of these aggressive invaders into the broader Delaware River ecosystem. [caption id="attachment_16006" align="alignright" width="394"] Provided by NJ Conservation Foundation[/caption] The Silty Pond Mussel was first discovered in the United States in 2010 at a former fish farm in Hunterdon County, now part of NJ Conservation Foundation’s Wickecheoke Creek Preserve. It is believed the mussels arrived as glochidia (a microscopic larval stage of some freshwater mussels) attached to the gills of bighead carp, another invasive species imported from China by the farm's previous owners. Initially overlooked and undocumented in North America, the mussels quickly established a foothold in the Preserve's ponds, threatening local ecosystems. These invasive mussels, which can grow to the size of a small football, form high-density colonies that pose a severe threat to native organisms. This aggressive species outcompetes native mussels for nutrients and habitat, altering water chemistry in the process and drastically depleting the local ecosystem of resources essential to native plants and animals. Additionally, once the Silty Pond Mussel glochidia attach to the gills of native fish, a biological reaction occurs that ultimately kills the host fish thus preventing native mussels from completing their own life cycle on these fish hosts. This dual impact — monopolizing food and habitat resources as adults while denying native mussels access to necessary host fish — makes the Silty Pond Mussel especially harmful to local ecosystems. Following the initial discovery, DNA testing conducted by the NJ Invasive Species Strike Team, New Jersey Endangered & Nongame Species Program, and the North Carolina State Museum of Natural Sciences confirmed the presence of this invasive species, marking the first documentation of the Silty Pond Mussel in North America. Early eradication efforts began shortly thereafter. Since 2019, a coalition of partners has expanded these efforts and remained committed to the complete eradication of the Silty Pond Mussel species. Led by NJDEP Fish & Wildlife and including organizations such as tthe U.S. Fish & Wildlife Service, NJ Conservation Foundation, Rutgers University, NJ Water Supply Authority, U.S. Department of the Interior's Office of Restoration and Damage Assessment (ORDA) and Princeton Hydro, the project has focused on surveying waterways using SCUBA, snorkel and physical analysis; utilizing environmental DNA (eDNA) testing to detect the presence of mussels in a waterbody; and applying targeted treatments. Community engagement and education are also central to these efforts, emphasizing the importance of collaboration in tackling this ecological threat. Geoffrey M. Goll, P.E., President of Princeton Hydro, emphasized the collaborative nature of the efforts: "This initiative exemplifies the power of partnership and innovation in tackling environmental challenges. Together, we are making significant strides in preserving our state's rich biodiversity." Protecting Biodiversity and Partnering for Eradication The Wickecheoke Creek Preserve, home to nearly 400 native plant species and a wide variety of wildlife, includes 14 miles of streams and flows directly into the D&R Canal, which supplies clean drinking water to one million New Jersey residents. New Jersey is also home to 12 native freshwater mussel species, nine of which are classified as Endangered, Threatened, or of Special Concern, further underscoring the the urgency of preventing this aggressive invasive species from spreading. Left unchecked, the Silty Pond Mussel could disrupt one of the most biodiverse freshwater regions in the country and cause significant ecological harm. Swift action to address this invasive species is essential to protecting the Wickecheoke Creek Preserve, safeguarding native species, and preserving the health of the Delaware River watershed. Each project partner plays an essential roles in the eradication process. Rutgers University is performing the environmental DNA (eDNA) monitoring and analyzing the results. Princeton Hydro is applying targeted treatments to the ponds where the mussels were initially detected, and, if eDNA or physical sampling reveals signs of the mussels in other water bodies, the team will extend these treatments accordingly. Using a highly specialized approach, Princeton Hydro’s licensed applicators have partnered with SePRO to apply Natrix, an EPA-registered pesticide developed specifically for managing invasive mollusk populations. The 2024 phase of the project has incorporated significant advancements in treatment design. The team’s strategy is both preventative and responsive. The project has garnered financial support from the U.S. Fish and Wildlife Service and the Delaware River Greenway Partnership through the Lower Delaware Wild and Scenic Program. [gallery link="none" ids="16013,16011,16010"] In addition to treatment, Princeton Hydro is focused on rigorous documentation and educational outreach. “It’s important for us to record every aspect of this project, not only from a scientific perspective but also for public education,” said the Princeton Hydro Director of Marketing & Communications Dana Patterson Grear. “We want to ensure this species is contained here and prevented from spreading throughout New Jersey or, worse, across the United States.” As part of these efforts, Princeton Hydro aims to share detailed information on the Silty Pond Mussel’s characteristics and identification markers. “By educating communities and environmental stakeholders on what to look for, we hope to empower rapid responses in other areas, should the species appear elsewhere,” said Patterson Grear. Dive Deeper: Watch the Video on Eradication Efforts As part of the project's commitment to transparency and education, New Jersey DEP Fish & Wildlife created a detailed video to showcase the silty pond mussel eradication and identification efforts. This video delves deeper into the techniques and collaborative approaches being used to address the invasive species. We encourage you to watch the video to gain a comprehensive understanding of the challenges faced and the innovative strategies employed in this groundbreaking effort. [embed]https://www.youtube.com/watch?v=qplXLi5tOPY[/embed] To learn more about invasive species, obtain practical tips for identifying and managing invasives, and take actions to help protect our local ecosystems, click here to check out our recent blog. [post_title] => A Groundbreaking Effort is Underway to Protect New Jersey Waters from Invasive Mussel Species [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => a-groundbreaking-effort-is-underway-to-protect-new-jersey-waters-from-invasive-mussel-species [to_ping] => [pinged] => [post_modified] => 2025-01-31 14:39:37 [post_modified_gmt] => 2025-01-31 14:39:37 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=16002 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 15793 [post_author] => 1 [post_date] => 2024-10-05 16:33:37 [post_date_gmt] => 2024-10-05 16:33:37 [post_content] => Invasive species may be impacting your backyard without you even realizing it. These non-native plants, animals, and organisms can harm ecosystems, the economy, and even human health when they take root in areas where they don’t naturally belong. If you missed our recent Facebook Live presentation on this important topic, don’t worry — the recording is now available for on-demand viewing! In the webinar, experts from the Princeton Hydro team - Michael McGraw, CSE, QAWB, ACE, Senior Project Manager and Senior Wildlife Biologist of Regulatory Compliance & Wildlife Surveys, and Jesse Smith, Aquatic Ecologist - provide practical tips on how to identify and manage invasive species, helping to keep your backyard and local environment thriving. What exactly are invasive species, and why are they so harmful to the ecosystems we rely on? Invasive species are organisms that are not native to an area but thrive and spread aggressively, often causing harm to native ecosystems. They compete for resources, disrupt habitats, and can introduce diseases, leading to the decline of native species. Unlike exotic species, which may be non-native but do not necessarily cause harm, invasive species tend to simplify ecosystems by outcompeting native plants and animals. A well-known example is the Emerald Ash Borer, a beetle responsible for the widespread death of ash trees across North America. Another, Phragmites australis, also known as Common Reed, is a highly invasive grass that dominates wetlands, lowering biodiversity and displacing native species. The spread of these and other invasive species can be exacerbated by human activity and even by climate change. In their natural environment, invasive species have predators and environmental checks that keep their populations under control. However, when introduced to new habitats, they lack these natural controls, allowing them to spread rapidly. Invasive species can alter ecosystems by:
Each year on March 3rd, World Wildlife Day offers an opportunity to celebrate the incredible biodiversity of our planet and raise awareness about the importance of protecting and restoring critical habitats. In that spirit, we’re highlighting a transformative project that turned degraded wetlands into a thriving wildlife sanctuary: The Pin Oak Forest Stream, Wetland, and Upland Enhancement Project in Woodbridge, New Jersey, stands as a testament to the power of restoration and the lasting impact of ecological stewardship.
Located in a highly developed region of Middlesex County, the Pin Oak Forest Conservation Area is a rare ecological gem—a 97-acre open space containing a critical wetland complex at the headwaters of Woodbridge Creek. Before restoration efforts began, the area suffered from habitat fragmentation, wetland degradation, and the encroachment of invasive species, all of which had significantly reduced biodiversity and threatened native wildlife.
Recognizing the urgency of intervention, a diverse coalition of government agencies, NGOs, and private industry, including Middlesex County Office of Parks and Recreation, Woodbridge Township, Woodbridge River Watch, New Jersey Freshwater Wetlands Mitigation Council, GreenTrust Alliance, GreenVest, and Princeton Hydro, came together to design and implement a comprehensive restoration plan aimed at revitalizing the area’s natural functions.
The project converted nearly 29 acres of degraded wetlands, over 1,000 feet of channelized streams, and disturbed uplands into a vibrant, species-rich ecosystem. By reconnecting the stream to its floodplain and incorporating microtopography techniques, the restoration team created a varied landscape that supports multiple habitat communities and improves groundwater infiltration—essential elements for sustaining wildlife.
The transformation of Pin Oak Forest into a high-functioning wetland complex has had profound impacts. The site now provides critical habitat for a range of species, including the state-threatened Black-crowned Night-Heron (Nycticorax nycticorax) and Red-headed Woodpecker (Melanerpes erythrocephalus). The reestablishment of native vegetation, such as pin oak (Quercus palustris), swamp white oak (Quercus bicolor), and swamp rose (Rosa palustris), has further enhanced the ecosystem, creating food sources and nesting areas for birds, amphibians, and pollinators.
By managing invasive species and allowing native flora to flourish, biodiversity has significantly increased. The restored headwater wetland system supports a delicate balance of aquatic and terrestrial life, creating a vital refuge for countless species amid an otherwise urbanized landscape.
This success story highlights how thoughtful ecological restoration can bring degraded environments back to life, providing a lasting benefit for wildlife and the surrounding community alike.
On this World Wildlife Day, the Pin Oak Forest project serves as an inspiring reminder of what’s possible when partnerships, science, and dedication converge to protect and restore critical habitats. The work done here is not just about the past—it’s about shaping a future where wildlife and people can thrive together.
At Princeton Hydro, we remain committed to advancing ecological restoration, ensuring that more landscapes like Pin Oak Forest can be revitalized for generations to come. We hope that by reflecting on the success of this project, more communities and organizations will be inspired to take action in preserving and restoring the natural world and pledge to protect the wildlife that makes our planet so extraordinary.
To learn more about the award-winning Pin Oak project and see additional restoration photos, click here.
An ambitious project is underway to eradicate the invasive Silty Pond Mussel (formerly known as the Chinese pond mussel, Sinanodonta woodiana) from the Wickecheoke Creek Preserve in New Jersey. This critical initiative seeks to protect local ecosystems, safeguard native aquatic species, and prevent the spread of these aggressive invaders into the broader Delaware River ecosystem.
The Silty Pond Mussel was first discovered in the United States in 2010 at a former fish farm in Hunterdon County, now part of NJ Conservation Foundation’s Wickecheoke Creek Preserve. It is believed the mussels arrived as glochidia (a microscopic larval stage of some freshwater mussels) attached to the gills of bighead carp, another invasive species imported from China by the farm's previous owners. Initially overlooked and undocumented in North America, the mussels quickly established a foothold in the Preserve's ponds, threatening local ecosystems.
These invasive mussels, which can grow to the size of a small football, form high-density colonies that pose a severe threat to native organisms. This aggressive species outcompetes native mussels for nutrients and habitat, altering water chemistry in the process and drastically depleting the local ecosystem of resources essential to native plants and animals. Additionally, once the Silty Pond Mussel glochidia attach to the gills of native fish, a biological reaction occurs that ultimately kills the host fish thus preventing native mussels from completing their own life cycle on these fish hosts. This dual impact — monopolizing food and habitat resources as adults while denying native mussels access to necessary host fish — makes the Silty Pond Mussel especially harmful to local ecosystems.
Following the initial discovery, DNA testing conducted by the NJ Invasive Species Strike Team, New Jersey Endangered & Nongame Species Program, and the North Carolina State Museum of Natural Sciences confirmed the presence of this invasive species, marking the first documentation of the Silty Pond Mussel in North America. Early eradication efforts began shortly thereafter.
Since 2019, a coalition of partners has expanded these efforts and remained committed to the complete eradication of the Silty Pond Mussel species. Led by NJDEP Fish & Wildlife and including organizations such as tthe U.S. Fish & Wildlife Service, NJ Conservation Foundation, Rutgers University, NJ Water Supply Authority, U.S. Department of the Interior's Office of Restoration and Damage Assessment (ORDA) and Princeton Hydro, the project has focused on surveying waterways using SCUBA, snorkel and physical analysis; utilizing environmental DNA (eDNA) testing to detect the presence of mussels in a waterbody; and applying targeted treatments. Community engagement and education are also central to these efforts, emphasizing the importance of collaboration in tackling this ecological threat.
Geoffrey M. Goll, P.E., President of Princeton Hydro, emphasized the collaborative nature of the efforts: "This initiative exemplifies the power of partnership and innovation in tackling environmental challenges. Together, we are making significant strides in preserving our state's rich biodiversity."
The Wickecheoke Creek Preserve, home to nearly 400 native plant species and a wide variety of wildlife, includes 14 miles of streams and flows directly into the D&R Canal, which supplies clean drinking water to one million New Jersey residents. New Jersey is also home to 12 native freshwater mussel species, nine of which are classified as Endangered, Threatened, or of Special Concern, further underscoring the the urgency of preventing this aggressive invasive species from spreading. Left unchecked, the Silty Pond Mussel could disrupt one of the most biodiverse freshwater regions in the country and cause significant ecological harm. Swift action to address this invasive species is essential to protecting the Wickecheoke Creek Preserve, safeguarding native species, and preserving the health of the Delaware River watershed.
Each project partner plays an essential roles in the eradication process. Rutgers University is performing the environmental DNA (eDNA) monitoring and analyzing the results. Princeton Hydro is applying targeted treatments to the ponds where the mussels were initially detected, and, if eDNA or physical sampling reveals signs of the mussels in other water bodies, the team will extend these treatments accordingly. Using a highly specialized approach, Princeton Hydro’s licensed applicators have partnered with SePRO to apply Natrix, an EPA-registered pesticide developed specifically for managing invasive mollusk populations. The 2024 phase of the project has incorporated significant advancements in treatment design. The team’s strategy is both preventative and responsive. The project has garnered financial support from the U.S. Fish and Wildlife Service and the Delaware River Greenway Partnership through the Lower Delaware Wild and Scenic Program.
In addition to treatment, Princeton Hydro is focused on rigorous documentation and educational outreach. “It’s important for us to record every aspect of this project, not only from a scientific perspective but also for public education,” said the Princeton Hydro Director of Marketing & Communications Dana Patterson Grear. “We want to ensure this species is contained here and prevented from spreading throughout New Jersey or, worse, across the United States.” As part of these efforts, Princeton Hydro aims to share detailed information on the Silty Pond Mussel’s characteristics and identification markers. “By educating communities and environmental stakeholders on what to look for, we hope to empower rapid responses in other areas, should the species appear elsewhere,” said Patterson Grear.
As part of the project's commitment to transparency and education, New Jersey DEP Fish & Wildlife created a detailed video to showcase the silty pond mussel eradication and identification efforts. This video delves deeper into the techniques and collaborative approaches being used to address the invasive species. We encourage you to watch the video to gain a comprehensive understanding of the challenges faced and the innovative strategies employed in this groundbreaking effort.
To learn more about invasive species, obtain practical tips for identifying and managing invasives, and take actions to help protect our local ecosystems, click here to check out our recent blog.
Invasive species may be impacting your backyard without you even realizing it. These non-native plants, animals, and organisms can harm ecosystems, the economy, and even human health when they take root in areas where they don’t naturally belong.
If you missed our recent Facebook Live presentation on this important topic, don’t worry — the recording is now available for on-demand viewing! In the webinar, experts from the Princeton Hydro team - Michael McGraw, CSE, QAWB, ACE, Senior Project Manager and Senior Wildlife Biologist of Regulatory Compliance & Wildlife Surveys, and Jesse Smith, Aquatic Ecologist - provide practical tips on how to identify and manage invasive species, helping to keep your backyard and local environment thriving.
Invasive species are organisms that are not native to an area but thrive and spread aggressively, often causing harm to native ecosystems. They compete for resources, disrupt habitats, and can introduce diseases, leading to the decline of native species. Unlike exotic species, which may be non-native but do not necessarily cause harm, invasive species tend to simplify ecosystems by outcompeting native plants and animals.
A well-known example is the Emerald Ash Borer, a beetle responsible for the widespread death of ash trees across North America. Another, Phragmites australis, also known as Common Reed, is a highly invasive grass that dominates wetlands, lowering biodiversity and displacing native species. The spread of these and other invasive species can be exacerbated by human activity and even by climate change.
In their natural environment, invasive species have predators and environmental checks that keep their populations under control. However, when introduced to new habitats, they lack these natural controls, allowing them to spread rapidly. Invasive species can alter ecosystems by:
Freshwater ecosystems and wetlands are particularly vulnerable because it’s hard to contain the spread of invasives in these environments. Once established, invasive species are difficult to remove and can cause long-term damage.
The good news is that there are steps we can take to help prevent and manage invasive species in our communities. Here’s what you can do:
Educate and Share: Education is one of the most powerful tools in fighting invasives. Learn about which plants are native and beneficial to your specific region. Talk with your neighbors, community organizations, and local land managers about the importance of managing invasive species. And consider sharing educational resources like this blog and our on-demand webinar.
Reduce the Spread: Prevention is the best strategy. By planting native species, removing invasives, and avoiding the release of invasive species into the environment, you can help stop the spread.
Monitor Your Property: Routinely checking your property for invasive species is key to early detection. Reach out to local watershed organizations to get involved in monitoring efforts. Get involved with organizations focused on monitoring and protecting local lakes and waterways. In Virginia, the Smith Mountain Lake Association has launched “Dock Watch,” a community science program where volunteers collect water samples from select docks to monitor harmful algal blooms, track cyanobacteria levels, and report invasive aquatic species.
Document and Report: Learn to identify common invasive species in your area and report them to local authorities, such as your county extension office or an invasive species management team. In New Jersey, the Invasive Species Strike Team works to control the spread of these harmful organisms.
Here are some methods to consider when removing Invasive Species:
To learn more about how invasive species may be impacting your backyard and what you can do to address them, we invite you to watch our webinar. Learn practical tips for identifying and managing invasives to help protect your property and local ecosystems. Click below to watch the webinar now:
We encourage you to share this blog and the webinar with your community. Together, we can help stop the spread of invasive species and protect our natural environments for future generations.
Nestled at the foot of the Blue Ridge Mountains, Smith Mountain Lake is the largest lake entirely within the Commonwealth of Virginia. Spanning over 20,000 acres with 500 miles of shoreline, the lake's northern and eastern boundary is marked by Bedford County, while Franklin and Pittsylvania counties define its southern and western edges. Created in 1963 by impounding the Roanoke River with the Smith Mountain Dam, the lake serves multiple purposes, including hydroelectric power, public water supply, and recreation.
Throughout the 1960s and 1970s, the area surrounding Smith Mountain Lake was predominantly rural farmland. In the 1980s, however, the lake's natural beauty, recreational appeal, and proximity to Roanoke and Lynchburg began to draw increased attention. This surge in interest sparked a boom in residential and commercial development, transforming Smith Mountain Lake into a vibrant and bustling community.
Today, Smith Mountain Lake not only provides electricity and drinking water, it is also home to 21,000 residents and stands as a premier recreational resource. Thousands flock to Smith Mountain Lake each year to enjoy boating, swimming, fishing, and other water activities. The lake's shores are now dotted with resorts, condominiums, year-round residences, and outdoor industry businesses. The lake's waters and shoreline also provide vital habitats for aquatic plants, animals, birds, and other terrestrial wildlife.
The rapid growth of this pristine lake community underscores the importance of effective environmental management to preserve water quality, strengthen the shoreline, manage stormwater runoff, and protect the local native biodiversity of the lake and its watershed.
The lake is fed by two main tributaries—the Blackwater River and the Roanoke River. The Roanoke River, the larger of the two, drains a watershed that includes the Roanoke Metropolitan area, while the Blackwater River flows through mostly rural and agricultural land.
In 2023, a significant outbreak of harmful algal blooms (HABs) in the Blackwater River subwatershed raised concerns for the Smith Mountain Lake Association (SMLA). These blooms, primarily driven by agricultural runoff, led to swimming advisories and highlighted the need for a comprehensive approach to managing and mitigating these environmental threats.
Recognizing the urgency of the situation, SMLA sought the expertise of Princeton Hydro. The mission: to investigate conditions that cause HABs, protect the lake from future outbreaks, and ensure the long-term health of this vital freshwater resource.
The project team’s approach began with a thorough review of historical water quality data. Collaborating with SMLA and regulatory bodies including the Virginia Department of Environmental Quality (VDEQ), U.S. Geological Survey (USGS), and U.S. Army Corps of Engineers (USACE), Princeton Hydro compiled a comprehensive dataset. This historical context was crucial for understanding past trends and informing the 2024 Watershed Assessment. SMLA and Ferrum College contributed over 38 years of data through their Volunteer Water Quality Monitoring Program, documenting crucial indicators such as nutrient levels, bacterial counts, and algal blooms. This extensive dataset has been essential in informing effective lake management practices and shaping strategies to address current environmental challenges.
Employing the MapShed model, the team carried out a comprehensive hydrologic and nutrient loading analysis of the Blackwater River subwatershed. They evaluated critical factors, including phosphorus, nitrogen, and sediment levels, to identify and prioritize areas requiring targeted nutrient and sediment management strategies.
To describe its basic function, the MapShed model applies pollutant loading rates to different land cover types, like low-density development or forested wetlands, based on their area. It then uses weather data, soil characteristics, and slopes to adjust these results. The model simulates daily pollutant loads over 30 years using actual climate records, providing monthly and annual outputs. Users can adjust various inputs, like septic system efficiency and population density, to see how the changes affect pollutant loads and water flow.
This analysis laid the foundation for determining effective, focused interventions to curb nutrient runoff and mitigate future HABs.
In March 2024, an Overwintering Incubation Study was conducted to understand cyanobacteria behavior. Sediment and water samples were taken from six nearshore locations known for high cyanobacteria counts in Summer 2023. At each site, the team also documented temperature, dissolved oxygen, specific conductivity, pH, chlorophyll-a, phycocyanin (PC), and phycoerythrin (PE).
The map below identifies the locations of each of the six sampling sites:
For each sample, the lake water was filtered and then incubated with respective sediments to determine the presence and what types of algae may be overwintering. The water and sediment samples were incubated over a period of 15 days at a temperature of approximately 77 degrees Fahrenheit and a light intensity of 2800 lux.
After eight days, the water and sediment samples were removed from the incubator, slightly stirred and then in-situ measurements for PC and PE were collected. These two supplemental pigments are almost exclusively produced by cyanobacteria. While PC is associated with primarily planktonic genera, PE is more associated with benthic genera. Thus, measuring the concentration of these pigments can be used to estimate cyanobacteria biomass as well as provide guidance on the monitoring and management of HABs (planktonic vs. benthic).
After 15 days, the samples were again removed from the incubator, slightly stirred, and then measured for PC and PE to identify and count any overwintering cyanobacteria and determine all the types of algae present.
This study offered critical insights into the conditions that enable cyanobacteria to endure winter and proliferate during warmer months. By understanding the connection between overwintering cyanobacteria and HABs in the lake, we can enhance predictive capabilities and develop more effective management strategies. Two particularly notable findings from the study include:
Beyond the initial assessment on the Blackwater River, ongoing monitoring of Smith Mountain Lake’s water quality is crucial for understanding and managing the conditions that trigger HABs. SMLA’s Water Quality Monitoring Program developed and managed by Ferrum College continues the work of tracking the trophic state of the lake. Algal community composition, tributary sampling, and bacterial monitoring are part of this comprehensive 38-year effort. Consistent sampling and water quality monitoring can help identify cyanobacteria and akinetes, the dormant spores that lead to bloom formation.
Because the VDEQ budget historically contains no funding for inland waterway HAB research and response, SMLA actively lobbied the Virginia General Assembly for the allocation of $150,000 for the creation of a watershed study. This request was included in the State budget signed in March of 2024 and the work to develop the objectives and scope of the study is underway now.
Community involvement is also vital for maintaining Smith Mountain Lake as a cherished resource. To this end, SMLA has launched "Dock Watch," a new community science volunteer program designed to monitor HAB activity. Beginning in May of 2024, volunteers have been collecting water samples at select docks around the lake and are examining them to better understand cyanobacteria activity levels and trends. All of the water quality data collected at the lake is from main channel locations. The primary recreational contact with the lake water by residents is at their docks. This data is uploaded to NOAA's Phytoplankton Monitoring Network, contributing to a national database used for HAB research. This collective effort ensures rapid identification and tracking of HAB activity, benefiting both the local community and environmental research on a national level.
“This project exemplifies a holistic approach to lake management and environmental stewardship, integrating historical data, advanced modeling, and community engagement to prioritize and implement innovative strategies that effectively mitigate HABs and protect water quality,” said Chris L. Mikolajczyk, Princeton Hydro’s Senior Manager of Aquatics and Client Manager for Smith Mountain Lake. “This ongoing work highlights the importance of science-based interventions in preserving our precious natural resources.”
The Smith Mountain Lake Association is a 501(c)3 nonprofit with the mission to keep Smith Mountain Lake clean and safe. Founded in 1969, SMLA is the longest serving advocate for the Smith Mountain Lake community, and its focused efforts help to retain the pristine beauty of the lake and the vibrant local economy. Click here to learn more and get involved.
Over the last two decades, the Princeton Hydro team has improved water quality in hundreds of ponds and lakes, restored many miles of rivers, and enhanced thousands of acres of ecosystems in the Northeast. From species surveys to water quality monitoring, our professionals perform comprehensive assessments in order to understand the landscape. Using tools like ArcGIS, we can map and model the watershed and arrive at holistic solutions for resource management. Our natural resources and lake management experts are complemented by our field team who utilize amphibious vehicles for mechanical invasive species removal, install aeration systems to improve water quality, and conduct natural lake treatments to manage algal blooms. We have secured millions of dollars in grant funding for watershed and ecological restoration projects on behalf of our clients.
Click here to learn about the Watershed Management Program in Somerset County, for which we recently helped secure grant funding from the New Jersey Highlands Water Protection and Planning Council.
In recognition of World Water Day on March 22, it's important to acknowledge and explore the challenges affecting our freshwater ecosystems. In this blog post, we explore one of those said challenges: Harmful Algal Blooms (HABs).
HABs, characterized by rapid overgrowths of cyanobacteria, have increasingly drawn attention due to their detrimental effects on water quality and aquatic ecosystems. With the onset of spring, rising temperatures create favorable conditions for cyanobacteria growth, setting the stage for potential bloom occurrences in the months ahead. Over recent summers, lakes and freshwater bodies across the nation have faced closures and health advisories due to HAB outbreaks, underscoring the urgent need to address this issue.
Cyanobacteria, often referred to as blue-green algae, are naturally occurring microorganisms in aquatic environments. However, under specific conditions—such as warm temperatures and nutrient-rich waters—these organisms can proliferate rapidly, forming blooms that pose risks to the health of humans, wildlife and aquatic species, local economies and overall ecological balance.
The interplay between climate change and HABs is undeniable: Rising temperatures and altered precipitation patterns create favorable conditions for cyanobacteria growth, exacerbating bloom occurrences. The absence of snow cover and early ice melt further accelerates this process, allowing cyanobacteria to flourish earlier in the year. Over the past few summers, lakes and fresh-waterbodies across the nation experienced closures and health advisories as a result of HAB outbreaks, emphasizing the urgency of addressing this issue.
In light of these challenges, proactive measures are crucial for mitigating the impacts of HABs. Early sampling efforts, initiated as early as March or April, enable the detection of cyanobacteria and akinetes, dormant spores that contribute to bloom formation. Additionally, reducing nutrient inputs, particularly phosphorus, into waterways is essential for preventing HABs.
As we reflect on the significance of water resources on World Water Day, it’s imperative to recognize the importance of addressing threats such as HABs. By raising awareness, fostering collaboration, and implementing effective strategies, we can work towards safeguarding the health and sustainability of our freshwater ecosystems.
In this spirit, we invite you to join the conversation at the Harmful Algal Bloom Summit 2024, hosted by the New Jersey Department of Environmental Protection. This virtual seminar, taking place on March 27, is free to attend and offers a platform for stakeholders to exchange insights, discuss best practices, and explore innovative solutions for managing HABs.
This year's Summit, which is titled “Unlocking the Puzzle of Harmful Algal Blooms," includes a keynote address and three educational sessions - "Growth Through Reflection: Lessons Learned," "Innovative Tools and Applications," and "Beyond the Numbers" - each featuring a variety of expert presentations. Princeton Hydro Senior Technical Director of Ecological Services Dr. Fred Lubnow is presenting on "Quantifying Overwintering Cyanobacteria and How They May Impact the Monitoring and Management of HABs."
Get more information and register here.
As we commemorate World Water Day 2024, let us reflect on the interconnectedness of water and life. Small actions taken today can have a profound impact on preserving water quality for future generations. Join us in making a commitment to promote and do our part to support a sustainable future for our freshwater ecosystems.
We are thrilled to announce the newest addition to our fleet: The Marsh Master® 2MX-KC-FH! This multi-functional, eco-friendly, and fully amphibious machine is specifically designed to work in wetland environments with minimal disruption to the delicate ecosystem.
One of the Marsh Master®'s primary roles is combating invasive and nuisance plant species, including the notorious non-native Phragmites australis, also known as Common Reed. Utilizing its innovative leveling and cutting mechanisms, this powerhouse of a machine efficiently knocks down and chops up sprayed or winter-weakened vegetation. Equipped with two powerful rotary blades, it effortlessly cuts through dense underbrush and tall marsh grasses, effectively controlling invasive weeds and problematic plant growth.
"We are committed to offering more non-chemical alternatives for aquatic invasive species control. The Marsh Master® 2MX-KC-FH is the second marsh buggy in our fleet," said Geoffrey M. Goll, President of Princeton Hydro. "This model is larger and more powerful, allowing us to cover more ground in a shorter period of time. Adding this machine to our fleet is an important investment in achieving our firm's environmental stewardship goals."
What sets the Marsh Master® apart is its versatility and low environmental impact. With its lightweight construction and advanced weight distribution system, it exerts low ground pressure and boasts high floating capacity. This allows the Marsh Master® to operate seamlessly on water, in deep or shallow depths, and on dry land without disturbing sensitive environments like nature preserves, wetlands, and canal banks. Its highly maneuverable design ensures easy passage through narrow channels and around hazards, making it the ideal choice for a wide range of applications.
But the Marsh Master® is not just a one-trick pony. With a wide array of tools and accessories, it can perform a variety of functions, from weed cutting and harvesting to debris removal to excavation to soil sampling.
During a recent project in Middlesex County, we put the Marsh Master® to the test to clear an area overrun with Phragmites australis. These invasive weeds not only create dense thickets unsuitable for native fauna but also outcompete local vegetation, leading to a decrease in plant diversity. Thanks to the Marsh Master®'s efficient cutting and rolling capabilities, we were able to expose the marsh plain and get it ready for planting of native vegetation in the Spring. This is just one example of how the Marsh Master is making a tangible difference in restoring delicate ecosystems.
Through a combination of prevention, early detection, eradication, restoration, research and outreach, we can protect our native landscapes and reduce the spread of invasive species. Learn more about our invasive species removal and restoration services.
In Warrington Township, Pennsylvania, an innovative ecological uplift initiative is underway at Lion's Pride Park. This project aims to transform a stagnant pond, overrun with invasive species and plagued by water quality issues, into a thriving wetland mosaic. This endeavor, a collaborative effort between Warrington Township, Princeton Hydro, and other stakeholders, promises to not only revitalize the natural environment but also enhance community access and education within the park.
Spanning 47 acres, Lion's Pride Park serves as a green oasis within the Township, offering a range of recreational and educational opportunities for visitors of all ages and abilities.
The pond within the park was in urgent need of restoration - heavy storm events caused the pond to overflow, which created flooding conditions in the park. The local native biodiversity was being threatened by nusiance and invasive species like water chestnut (Trapa natans). The photos below were taken in April 2020.
Princeton Hydro began in 2020 with site investigation and field surveys, including:
The most substantial component for the restoration project was the conversion of the existing pond to an emergent wetland complex to provide habitat for a wide variety of native species. Using the completed existing conditions reports and surveys, Princeton Hydro prepared the conceptual design plan that informed the entire restoration process.
Princeton Hydro Regulatory Compliance & Wildlife Surveys Project Manager Emily Bjorhus, PWS spearheaded the regulatory program for the project, navigating approvals from the Pennsylvania Department of Environmental Protection (PADEP), the U.S. Army Corps of Engineers (USACE), and the Bucks County Conservation District. The permitting process laid the groundwork for the smooth implementation of this design-build restoration project.
The restoration work encompassed various stages, from earthwork and vegetation planting to the installation of ADA-compliant pathways and informational signage. Some of the key project elements, include:
Channel stabilization: Stabilizing the channels within the park, addressing erosion issues, enhancing water flow dynamics, and promoting the establishment of diverse aquatic habitats.
Berm construction: Installing berms to enhance wetland habitat and promote natural floodplain connectivity, contributing to the resilience of the ecosystem to flooding events.
Native vegetation planting: Reintroducing native wetland and riparian plant species to enhance biodiversity and create habitat corridors for wildlife within the park. Planting is expected to take place in the Spring.
Boardwalk installation: Constructing a 6-foot-wide ADA-compliant boardwalk that spanned approximately 230 linear feet, providing visitors with accessible pathways to explore the restored wetland areas.
Through these strategic interventions, the Lion's Pride Park Ecological Restoration Project aims to not only rejuvenate the ecological integrity of landscape but also enrich the recreational and educational experiences of the community. The project, which is slated for 100% completion this Spring, will totally transform the landscape into a diverse wetland complex that fosters native wildlife habitat, mitigates water quality concerns, reduces nonpoint source pollutants discharged to downstream waters, and provides accessible pathways and observation platforms so all community members may enjoy and learn from this restored aquatic setting.
The reclaimed wetland provides additional bird and pollinator habitat and offer visitors a diverse ecosystem to learn from within the park. By fostering a deeper connection to nature and promoting environmental stewardship, this project exemplifies the transformative power of ecological restoration in creating vibrant, sustainable communities.
On March 23, at the 2024 Watershed Congress hosted by the Delaware Riverkeeper Network, Emily will be presenting about the Lion's Pride Park Ecological Restoration Project. Her presentation will offer insights into the regulatory approval and permitting process, takes a deeper dive into the restoration strategies, and showcases the ecological significance of the project. Click here to learn more about the 2024 Watershed Congress.
Emily, a certified Professional Wetland Scientist, is a Project Manager that specializes in environmental regulatory compliance, ecological services and wildlife surveys. She leads federal, state and local environmental permitting processes, NEPA compliance and documentation, Endangered Species Act Section 7 consultations, and Clean Water Act Section 404(b)1 analyses.
The Lion's Pride Park Ecological Restoration Project exemplifies a holistic approach to environmental conservation, community engagement, and public recreation. By repurposing a neglected pond into a vibrant wetland mosaic, this initiative embodies the principles of ecological resilience and inclusive urban planning, and celebrates the transformative potential of ecological uplift projects in fostering healthier, more vibrant communities.
Please stay tuned to our blog for more project updates once planting is completed this Spring. Click here to read more about Princeton Hydro’s robust natural resource management and restoration services.
Mark Gallagher, Vice President of Princeton Hydro, has been appointed to the Friends of Abbott Marshland Advisory Board.
The Abbott Marshlands is composed of 3,000 acres of wetlands and uplands located on the western edge of central New Jersey in Mercer County. It is the northernmost freshwater tidal marsh on the Delaware River and contains valuable habitat for many rare species like River Otter, American Eel, Bald Eagle, and various species of wading birds.
Unfortunately, this ecosystem has faced challenges partially due to the invasion of the aggressive Common Reed (Phragmites australis), causing substantial habitat loss and degradation. In response to these challenges, the Friends for the Abbott Marshlands have dedicated themselves to enhancing appreciation and protection of this precious ecosystem. Their mission focuses on engaging and inspiring a diverse community to experience the unique nature and history of the Abbott Marshlands. Their priorities involve expanding community involvement, advancing educational programs through the Tulpehaking Nature Center, enhancing organizational capacity, and working in cooperative stewardship efforts.
Since its inception, the Friends for the Abbott Marshlands have played a pivotal role in advocating for the preservation and stewardship of the marshlands. They've organized various educational programs, symposia, nature walks, and juried photography shows to raise awareness and encourage stewardship of this unique ecosystem. The Friends for the Abbott Marshlands Advisory Board meets periodically to advise on program design and execution, fundraising, and engagement in any and all activities related to the preservation of the Abbott Marshlands.
The area is named "Abbott Marshlands" in recognition of the important archaeological legacy of the marsh and of Charles Conrad Abbott, a 19th and early 20th century archaeologist and naturalist, who lived on the bluffs near the marsh and who wrote extensively about it.
Recognizing the urgent need to restore the Abbott Marshlands, Mercer County contracted Princeton Hydro to spearhead a multi-year, multi-phased restoration initiative. The project aimed at reducing and controlling the invasive Phragmites australis while increasing the presence of native marsh vegetation.
Princeton Hydro conducted a Floristic Quality Assessment to identify invasive areas and to establish a baseline for the restoration efforts. The team also performed hydrologic monitoring to understand tidal stage elevations. From 2018-2019, herbicide treatments were consistently conducted to combat the invasive phragmites. In the winter of 2019-2020, 46 acres of phragmites was cut and rolled with our Marsh Master using a modified steel roller attachment. The phragmites was then removed by raking, which in turn exposed the marsh plain’s substrate and seedbank to promote germination of the native marsh vegetation. Extensive areas of wild rice, mud plantain, broad leaved cattail, water purslane, pickerelweed, and arrow arum colonized the areas formerly overtaken by phragmites within the first growing season after the marsh plain was exposed. The project also includes the creation of 500 linear feet of living shoreline, a freshwater mussel bed, and a sustainable boat launch.
This comprehensive and collaborative restoration effort not only targets invasive species but also focused on enhancing biodiversity; improving recreational opportunities such as kayaking and bird watching; enhancing the overall visitor experience at John A. Roebling Memorial Park, which is part of Abbott Marshlands; and creating opportunities for community engagement and appreciation of this natural treasure.
Click here to learn how you can get involved with supporting and participating in initiatives aimed at protecting and cherishing the Marshlands for generations to come. To take a deeper dive into Princeton Hydro's work at Abbott Marshlands, click here.
A founding partner of Princeton Hydro, Mark is a pioneer in the field of restoration ecology, and helped get the conservation science movement off the ground in the 1980s. He holds a Bachelor of Science in Biology from Moravian College and Master of Science in Plant Ecology from Rutgers University. For more than two decades, Mark has overseen wetland and terrestrial ecology projects at Princeton Hydro, including many complex restoration projects that require unique solutions.
Mark, along with Princeton Hydro team members Dana Patterson and Michael Rehman, CERP, PWS and representatives from Mercer County and Friends of the Abbott Marshlands, led a educational course and field exploration of the Abbott Marshlands as part of the New Jersey Department of Environmental Protection (NJDEP) annual Youth Inclusion Initiative. Learn more here.
The New Jersey Department of Environmental Protection (NJDEP) has launched its third annual Youth Inclusion Initiative. The program hopes to enrich young participants, who may not have the opportunity to explore open spaces in their community, with hands-on environmental field experience under the tutelage of NJDEP professionals and mentors.
This year’s youth consists of 47 participants from ages 16-20 that hail from five different community-based organizations. These partners include Neighborhood Improvement Association (Trenton), Rutgers-Camden, Groundwork Elizabeth, Ironbound Community Corporation (Newark), and The Work Group (Camden).
Over the course of this six week program, the youth participated in a curriculum that showcased career pathways in the water resources and natural resources management fields. Participants learned through classroom instruction and by receiving some in-field experience across sectors regulated by NJDEP such as touring an air monitoring station, visiting a trout hatchery, conducting stream assessments, and practicing proper tool and equipment recognition at a state park. After their time with the initiative is through, they will have nurtured the skills to pursue these job opportunities and develop a deeper appreciation for our environment.
Princeton Hydro representatives Mark Gallagher, Dana Patterson, and Michael Rehman, CERP, PWS led one of the mentorships. This is the second year NJDEP’s Division of Land Resource Protection Mitigation Unit invited Princeton Hydro to teach a portion of the program. The goal in participating was to educate the youth about the importance of restoring native landscapes and explore the job responsibilities of environmental scientists, water resource engineers, geologists, ecologists, pesticide applicators, and regulatory compliance specialists, while building upon and cultivating fascination with nature.
The program kicked off with a presentation in Mercer County Park Commission’s Tulpehaking Nature Center located in John A. Roebling Park. After learning about the history of the site from representatives from Mercer County and Friends of the Abbott Marshlands, Princeton Hydro discussed opportunities for careers in conservation and gave a brief overview of the restoration efforts in the park to eradicate the invasive Common Reed (Phragmites australis). Prior to heading out to explore the Abbott Marshlands, the northernmost freshwater tidal wetlands on the Delaware River, the Princeton Hydro team went through a health and safety briefing, a very important part of our job, to make sure everyone was aware of the potential risks and exposures.
Princeton Hydro team members and NJDEP’s Environmental Specialist Jessica Klein led the participants through the park. Right away, the first group witnessed one of nature’s marvels when they spotted a Northern Red-bellied Cooter (Pseudemys rubriventris) laying her eggs along the side of the main road. Participants learned of the marshland and surrounding upland’s rich cultural significance. On their trek through this natural oasis, they followed in the footsteps of the Lenape, a tribe of Native Americans who regularly visited and eventually settled in the area at least 13,000 years ago. These early nomadic people relied on the land for food, fuel, and other readily available resources until they were displaced due to European settlement along the Delaware River. Learn more about the Abbott Marshland cultural history here.
Eventually, the group made it to the area of the restoration site. Here, the students gained a better understanding of the harsh effects that invasive species have on an ecosystem. The 3000-acre freshwater tidal marsh provides habitat to many rare and endangered species, but it has experienced a significant amount of degradation due to monoculture of the invasive Common Reed. In order to improve the area’s biodiversity and elevate visitors’ recreational experience, Princeton Hydro implemented a restoration plan that aimed to eradicate the aggressive non-native plants within a 40-acre stretch of the marsh and enable native plants like Wild Rice (Zizania aquatica) to flourish. Learn more about this project.
NJDEP Commissioner Shawn LaTourette surprised the Rutgers-Camden group with his joyful presence. After giving a zealous speech to the class, he accompanied them on their journey to the marshland.
Overall, participants had fun learning how to use a field guide to identify invasive species found within the area. They were taught how to differentiate them with native flora like sensitive fern, poison ivy, and wild rice. With a wide survey of the marshland, the youth were taught about wetland delineation and got a peek into the process of using a hand auger and a Munsell Soil Color Book to identify wetland soils. Utilizing binoculars, the last group was lucky to spot a Northern Harrier, an uncommon visitor for the marshland, soaring circles in the sky in search of prey. The rare sighting led to the successful end of the final tour.
Harmful Algal Blooms (HABs) represent the rapid proliferation of cyanobacteria, also known as blue-green algae. While cyanobacteria are not technically algae but rather single-celled aquatic organisms related to bacteria, they possess the ability to photosynthesize like algae. These tiny microorganisms naturally inhabit aquatic ecosystems. However, under specific circumstances, such as heavy rainfall followed by scorching sunshine, they can rapidly multiply, resulting in the formation of cyanobacteria blooms, commonly known as HABs.
HABs can wreak havoc on waterbodies, leading to significant water quality issues and the unsightly appearance of surface scum, sometimes accompanied by unpleasant odors. The consequences extend beyond aesthetics and pose economic challenges for communities reliant on local lakes and waterways for jobs and tourism. Furthermore, HABs can produce highly toxic substances that pose serious risks to humans, aquatic life, and animals, including our beloved pets, wildlife, and livestock.
The effects of HABs on animals vary depending on factors such as the animal's size, exposure to cyanobacteria, duration of exposure, specific toxin types, and concentrations. Animals are often the first victims, drawn to bodies of water containing cyanobacteria due to their natural instincts. Dogs, in particular, are vulnerable as they may unwittingly ingest contaminated water during play. Livestock and wildlife are also at risk when drinking from contaminated water sources.
In 2021, researchers published a groundbreaking study linking cyanobacteria-generated neurotoxins to the deaths of eagles and waterbirds. After extensive research spanning three decades, scientists determined that cyanotoxins are responsible for a fatal neurological disease called vacuolar myelinopathy, commonly affecting waterbirds, raptors, and bald eagles.
Cyanobacterial poisoning symptoms can manifest within minutes to a few hours, depending on the severity of exposure. Dogs, in particular, may exhibit symptoms rapidly. Common signs include an accelerated heart rate, breathing difficulties, excessive salivation, disorientation or depression, vomiting or diarrhea, skin irritations, and neurological symptoms such as muscle weakness, dizziness, seizures, or paralysis.
It is crucial to seek immediate veterinary care or contact the Poison Control Center if you suspect your pet or livestock may be experiencing symptoms caused by harmful algae, cyanobacteria, or their toxins. The following 24-hour pet poison hotlines are available for assistance:
To protect your pets and livestock, avoid letting them come into contact with surface scums or heavily discolored water. In case of exposure, rinse them with clean water as soon as possible, as HABs can cling to their fur and pose health risks when they groom themselves. This is particularly important because certain HABs release fast-acting nerve toxins that can be especially dangerous for dogs swimming in affected areas.
Here are some additional steps you can take to safeguard yourself and your pets from the harmful effects of algae and cyanobacteria:
By staying informed and implementing necessary precautions, we can protect ourselves, our pets, and the environment from the risks associated with HABs. For further HABs related information and guidance, click here to watch a Facebook Live presentation with Princeton Hydro HABs experts. To get involved with monitoring and tracking harmful algal blooms, check out the bloomWatch App, a valuable tool for identifying and reporting potential HAB sightings to local authorities.
In the late 1920s, the U.S. government began allocating funds for road construction in U.S. national forests. This led to hundreds of thousands of culverts being built and installed across the country for the purpose of moving water quickly and efficiently underneath the roadways to prevent flooding, minimize erosion, and provide pathways for stormwater.
However, culverts have had an unintended and significant consequence: they block the migration routes of some fish and aquatic organisms.
Culverts that are undersized, improperly placed, or designed with smooth featureless surfaces can impede or totally block fish and aquatic species from passing. Culverts with extremely high velocity flows make it incredibly difficult for aquatic organisms to navigate upstream, and extremely low velocity flows make it hard for fish to pass in either direction. The high-velocity flows can erode the stream channel immediately downstream of the culvert, which can leave the culvert pipe perched. This elevation above the water channel makes it impossible for organisms to pass through. Debris can also collect in the culvert, not only blocking fish passage, but water as well.
In addition to blocking the upstream passage of fish and other aquatic species, some culverts disrupt the normal stream movements of some macroinvertebrates, which are key components of these stream ecosystems, an important food source to countless species, and play a critical role in the cycling of energy and nutrients throughout stream ecosystems. Disruptions to the movement and dispersal of stream macroinvertebrates can reduce available habitat, lead to genetic isolation of some populations, and cause extirpation of critical species. When populations splinter, it causes a reduction in genetic diversity, which can lead to the spread of more invasive species and many other ecological issues.
While culverts serve an important function in road construction and flood prevention, their impact on aquatic organisms must be taken into consideration. Finding solutions that both allow for efficient water flow and enable safe aquatic migration is crucial in preserving the health of our waterways and their ecosystems.
A shift in the 1980s recognized the importance of redesigning road-stream crossings for several reasons, including restoring aquatic organism passage and maintaining flood resilience. Between 2008 and 2015, U.S. Forest Service (USFS) partnered with more than 200 organizations in the Legacy Roads and Trails Program to replace 1,000+ culverts across the country. The aim of the program was to upgrade culverts to emulate natural streams and to allow fish and wildlife to pass more naturally both upstream and downstream.
Replacing culverts with structures that better facilitate the movement of both water and aquatic organisms has benefits beyond restoring critical ecosystems and improving biodiversity. Ecological restoration creates jobs, stimulates outdoor recreation and local economic activity, and generates long-term economic value.
Princeton Hydro has a strong history in designing connectivity-friendly road-stream crossings and restoring/replacing outdated culverts. Our team of engineers and scientists has been directly involved with hundreds of stream and ecosystem restoration projects throughout the Northeast.
For several years, Princeton Hydro has partnered with NY-NJ Harbor & Estuary Program (HEP) to plan and design for aquatic connectivity through climate-ready infrastructure. Created by the U.S. Environmental Protection Agency (USEPA) at the request of the governors of New York and New Jersey, HEP develops and implements plans that protect, conserve and restore the estuary, and aquatic connectivity is a key focus area for HEP and its partners.
Most recently, HEP partnered with Princeton Hydro to address hydraulic capacity issues at priority road-stream crossings in New Jersey’s South River and Lower Raritan River watersheds. The Princeton Hydro team developed a 30% engineering plan for a priority road-stream crossing – the Birch Street crossing over the Iresick Brook in Old Bridge, NJ.
Iresick Brook is upstream from Duhernal Lake, located at the end of the free-flowing South River, which feeds into the Raritan River, and ultimately flows into Raritan Bay. Duhernal Lake is dammed at the outlet so there is little to no connectivity downstream from the Iresick Brook sub-watershed. The watershed is highly dendritic (meaning the drainage pattern follows a tree-like shape) with many small streams running through it, some of them ephemeral.
The Iresick Brook 5 (IB5) culvert, located in Old Bridge Township, New Jersey, is an undersized double culvert in poor condition with an eroding streambank. This culvert was chosen as a restoration priority primarily due its inadequate sizing (both pipes are only 3-feet in diameter). The outdated infrastructure blocks the passage of fish and other aquatic organisms, and it can only accommodate a 50-year storm event.
Once the IB5 culvert was identified as the priority site, Princeton Hydro completed a site investigation, which included a geomorphic assessment, site observations, and simplified site survey of the channel alignment, profile, and cross sections both upstream and downstream of the culvert.
At the time of the survey, flow was only a couple inches deep in the channel and incredibly slow-moving, especially in the upstream reach. Despite the low flow at the time of the survey, during storm events, the stream experiences extremely high velocities. The undersized culvert creates hydraulic constriction and subsequently a velocity barrier that prevents passage. Additionally, when the high-flow stream water is forced through the small pipes, it creates a firehose effect, which has led to the formation of a 60-foot-long scour hole at the culvert outlet. Substrate from the scour hole has been washed downstream, forming an island of large sand and small gravel.
Approximately 155 feet upstream of the culvert is a channel-spanning v-notch weir comprised of a combination of sheet pile and timber. The weir appears to be a historical stream gauge that is highly degraded and creates an artificially perched channel. The upstream channel also contains woody debris, which gets caught at the culvert, blocking water flow and organism passage.
For the design process, Princeton Hydro used the USFS Stream Simulation Design, an gold-standard ecosystem-based approach for designing and constructing road-stream crossings that provide unimpeded fish and other aquatic organism passage through the structure. The Stream Simulation, a required standard on USFS road projects, integrates fluvial geomorphology concepts and methods with engineering principles to design a road-stream crossing that contains a natural and dynamic channel through the structure so that fish and other aquatic organisms will experience no greater difficulty moving through the structure than if the crossing did not exist.
The design also incorporated utility constraints (gas line, sewer line, drinking water main, and stormwater outlet), a longitudinal profile assessment, channel capacity and slope analysis, and a simplified hydrologic & hydraulic assessment.
Ultimately, Princeton Hydro recommended that HEP replace the existing culvert with a Contech Precast O-321 culvert, or similar alternative. The proposed design increases the culvert opening area and allows for significant increases in flow capacity. This culvert replacement project has the potential to reduce local flood risk and restore aquatic organism passage to the reach of Iresick Brook.
Aquatic connectivity is crucial for improving healthy aquatic ecosystems and managing severe storms and flooding. Increases in rainfall due to climate change makes investing in these improvements even more of a growing priority. With so many culverts in place, it can be difficult to know which culvert restoration projects to prioritize.
We worked with HEP to create a toolkit for addressing problematic road-stream crossings. The easy-to-use matrix helps to prioritize potential projects and identify solutions for problem culverts and relative cost solutions.
The toolkit was just recently released to the public with the hope that it will be used as a template to promote the development of more resilient and environmentally-friendly infrastructure.
Click here to get more info and download.
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