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Soil analysis is an essential part of environmental science, providing key insights into land composition, hydrology, and ecological health. In this installment of our "Field Notes" blog series, where we explore essential tools used by Princeton Hydro’s team, we take a deep dive into the Munsell Soil Color Chart—a standardized system that allows professionals to classify and communicate soil characteristics with accuracy. This tool is particularly useful in wetland delineations, where soil color helps determine whether an area meets the criteria for wetland classification.
What if the ground beneath your feet could tell a story? Soil isn’t just dirt; it’s a dynamic, living record of the landscape’s history, composition, and ability to sustain life. One of the most revealing clues in soil analysis is color, which reflects key properties such as drainage, organic matter content, and oxidation levels.
One key application of the Munsell Soil Color Chart is in wetland delineation, a process that determines whether a particular area meets the hydrologic, vegetative, and soil criteria for wetland classification. Soil scientists use an auger to extract a sample from the ground, where the first 6 to 12 inches, also known as the upper part, of the soil profile is the most important for determining whether the soils are hydric.
Hydric soils are defined as those that form under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part of the soil. The landscape of the site also plays a crucial role in hydric soil development. Factors such as hydrology, slope, landform, soil materials, and vegetation influence how these conditions emerge. These environmental factors trigger biogeochemical processes that lead to the development of distinct hydric soil indicators, including:
Once a scientist identifies a hydric soil, they refer to the Munsell Soil Color Chart to classify its matrix color and any hydric soil indicators present. This classification helps determine whether the area qualifies as a wetland under regulatory guidelines.
Before conducting a wetland delineation, Princeton Hydro Environmental Scientist Ivy Babson, PWS, first determines which United States Army Corps of Engineers (USACE) Wetland Delineation Region her site is located in—an essential step for ensuring proper classification. For a recent wetland delineation, Ivy identified her site as being within the Northcentral and Northeast Region and conducted pre-delineation research, which revealed that the area was characterized by shallow bedrock and exposed boulders.
Upon arriving at the site, Ivy observed that the wetland had formed within an old basin. The sloped basin floor supported hydrophytic vegetation, including cattails, sedges, and rushes, with visible drainage patterns and hummock-hollow microtopography indicating prolonged wet conditions.
Once Ivy selected a suitable location for a soil boring, she used a Dutch auger to extract a soil sample. The first 6 inches of the profile revealed very dark mineral soils with a high amount of decomposed organic material. Using the Munsell Soil Color Chart, she classified the sample as 10YR 2/1—a black, saturated mucky loam.
She also identified strong brown (7.5YR 4/6) redoximorphic features along plant root pore linings, indicating iron reduction due to prolonged saturation:
The next six inches of soil maintained a similar composition before transitioning at nine inches to a gray clay layer (10YR 5/1) with many yellowish-brown (10YR 5/6) redoximorphic features occurring as reduced iron soft masses, another clear indicator of prolonged saturation:
By 15 inches, Ivy hit bedrock, confirming that groundwater was perched above the rock layer, creating the saturated conditions necessary for hydric soil development.
To determine whether the site met wetland criteria, Ivy referred to the USACE’s Regional Supplement to the Wetland Delineation Manual, which provides region-specific hydric soil indicators. She identified several key indicators in her soil profile:
The combination of these four hydric soil indicators proves that the area is a wetland and is subject to conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part of the soil—a conclusion supported by the area's shallow bedrock, high water table, and saturated soil conditions.
Ivy draws a unique parallel between soil analysis and Vincent van Gogh’s Starry Night, transforming scientific observation into an artistic analogy:
"Looking at the Starry Night painting, my eyes are immediately drawn to the bright yellow stars and white moon against the dark blue night sky. In soil analysis, the dark blue sky represents the matrix of the soil, while the bright stars and moon resemble hydric soil indicators that ‘pop’ out. The streaking cypress tree in the painting? That’s like a redoximorphic concentration of manganese forming around a plant root. Just as these elements make Van Gogh’s painting unique, hydric soil indicators reveal the unique story of the land beneath our feet."
Beyond wetland delineation, soil classification is a key component of environmental restoration, conservation planning, and land management. The ability to analyze and interpret soil properties helps scientists understand long-term landscape changes, assess soil health, and develop strategies for sustainable land use.
The Munsell Soil Color Chart is particularly valuable in tracking environmental shifts. Subtle variations in soil color can indicate changes in moisture levels, organic content, or chemical composition—factors that influence everything from erosion control to habitat restoration. Soil analysis can reveal how a site has responded to past land use or whether a conservation area is recovering as expected.
By decoding soil characteristics with precision, environmental professionals can make informed decisions that support healthy ecosystems, improve water management, and guide responsible development. The Munsell Soil Color Chart remains a trusted resource in this process, providing a universal language for soil classification and environmental assessment.
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.
The New Jersey Department of Environmental Protection (NJDEP), U.S. Army Corps of Engineers (USACE), project partners, and elected officials broke ground on the interior cleanup of Liberty State Park in Jersey City (Phase 1A), marking a significant milestone in the history of New Jersey’s most visited state park.
During the groundbreaking ceremony, participants heard presentations from Commissioner of Environmental Protection Shawn M. LaTourette, USACE New York District Commander Colonel Alex Young, Assemblywoman Angela McKnight, and Assemblyman William B. Sampson IV.
As quoted in the press release distributed by the Murphy Administration, Commissioner LaTourette said, “Today’s groundbreaking is a critical step toward building a future at Liberty State Park that brings people and communities together to enjoy the environment we all share. Through the cleanup and restoration of nearly 235 acres, we will reckon with the industrial pollution of our past and from it, create a world-class outdoor urban environment that will be enjoyed by many future generations.” Click here to read the full press release.
A long history of industrial contamination (also called legacy pollution) has left 235 acres of Liberty State Park fenced-off and inaccessible to the public for decades. The groundbreaking ceremony marks the official start of Phase 1A of the clean up and restoration project.
Princeton Hydro was contracted by USACE New York District in partnership with the NJDEP Office of Natural Resource Restoration to design a resilient coastal ecosystem within 235 acres of this highly urbanized setting that provides both ecological and social benefits. This includes the restoration of over 80 acres of tidal and non-tidal wetlands and creation of several thousands of feet of intertidal shoreline and shallow water habitat hydrologically connected to the Upper New York Bay. When constructed, this will be one of the largest ecosystem habitat restoration projects in New Jersey.
A wetland is a unique ecosystem that is permanently or seasonally saturated by water, including swamps, marshes, bogs, vernal pools, and similar areas. They provide water quality improvement, flood protection, shoreline erosion control, food for humans and animals, and critical habitat for thousands of species of aquatic and terrestrial plants, aquatic organisms, and wildlife.
Princeton Hydro is regionally recognized for its capabilities in the restoration of freshwater and saltwater wetland ecosystems. Our ecologists also regularly conduct wetland delineations. A wetland delineation, a requirement of most permitting efforts, is the field work conducted to determine the boundary between the upper limit of a wetland and the lower limit of an upland thus identifying the approximate extent and location of wetlands on a requested site.
For this edition of our “A Day in the Life” blog series, we join Environmental Scientist Ivy Babson and Regulatory Compliance & Wildlife Surveys Project Manager Emily Bjorhus, PWS out in the field for a wetland delineation.
Most commonly, wetlands are delineated based on the Routine Onsite Determination Method set forth in the Federal Manual Identifying and Delineating Jurisdictional Wetlands (FICWD 1989) with supplemental information provided by the applicable United States Army Corps of Engineers’ (USACE) regional supplement manual.
USACE’s “three-parameter” approach defines an area as a wetland if it exhibits, under normal circumstances, all the following characteristics:
Ivy and Emily begin by coordinating with the client to ensure they’ve been granted site access approval.
They then perform a comprehensive desktop analysis of the project site, identifying existing features like wetlands, open waters (streams, lakes), and potential hydric soils. This involves utilizing resources like USFWS's National Wetland Inventory Mapper, the U.S. Geological Survey's SSURGO Soils Survey, and, for New Jersey-based delineations, NJDEP's GeoWeb. The desktop review also allows Ivy and Emily to assemble the proper safety gear and create a Model Health & Safety Plan (HASP). A HASP must always be prepared before the field work begins.
It's always important to make a plan for the project. If we are delineating a large property, it might take several days to traverse, and each day, the weather might be different. So planning ahead, but also being prepared for unexpected changes, will make the day go that much smoother. And, as part of the HASP, we must identify important points of contact and know where the closest hospital is in case of a serious emergency. So, reviewing this information and planning ahead prior to heading into the field is a very important step in the process.
While wetland delineations can be conducted any time of the year, they are best conducted during the “growing season” when soil temperatures are above the biologic zero and vegetation is easily identifiable by leaves, inflorescence, or other unique identifying characteristics that would otherwise be difficult to identify during the winter months.
Ivy and Emily begin by locating known (mapped) wetland or waterbody features and writing a list of all plants observed on-site. They maintain the plant list throughout the day.
If, during the desktop review, they find a mapped wetland or stream, they walk there first to determine if wetlands are actually present. Even if a wetland is mapped on a database, it may not actually exist for various reasons. On the flip side, even if a site is not mapped as containing wetlands, the site could very well contain them. As such, the wetland delineation determines exactly what is on-site and supplements the desktop review.
As mentioned above, a wetland delineation considers three determining factors: 1) vegetation, 2) soils, and 3) hydrology. While on site, Ivy and Emily must identify hydrophytic vegetation, take soil borings, and look for wetland hydrology to identify whether a wetland is present or not.
Wetlands are dominated by hydrophytes which are plants that can grow in water or on a substrate that is at least periodically deficient in oxygen because of excessive water content and depleted soil oxygen levels.
The USACE and NJDEP definition of hydrophytes is based on the USFWS classification system. In general, any plant species that is found growing in wetlands more than 50% of the time is considered a hydrophyte. These plants include those classified by the USFWS as “facultative," “facultative wetland," or “obligate."
As a wetland delineator, it is important to possess strong plant identification skills and an eye for recognizing various ecological plant communities, which are groups of plants that share a common environment and environmental requirements. They are often defined by dominant plant species.
Once Ivy and Emily identify the hydrophytic plant community, they determine what type of ecological community they are in (e.g., freshwater forested wetland, estuarine scrub-shrub wetland, or freshwater tidal emergent marsh). Today, they are in a freshwater forested wetland, which means Ivy and Emily must now assess each stratum of the forested wetland by writing down the species and associated percent species cover.
To accurately describe the vegetation at each sampling point, we collect data on each horizontal strata or layer. Vegetative strata for which dominants are determined include (1) tree (> 5.0 inches diameter at breast height (DBH) and 20 feet or taller); (2) sapling (0.4 to <5.0 inches DBH and <20 feet tall); (3) shrub (usually 3 to 20 feet tall including multi-stemmed, bushy shrubs); (4) woody vine; and (5) herb (herbaceous plants including graminoids, forbs, ferns, fern allies, herbaceous vines, and tree seedlings). They repeat this process for each representative wetland.
Next, Ivy and Emily look for the upland plant community that is directly upslope of the wetland and make note of the proximity to the wetland, repeating the same vegetation documentation process.
Ivy and Emily must determine whether the soils within the hydrophytic plant community are hydric. Hydric soils are defined as soils that are saturated, flooded, or ponded long enough during the growing season to develop anaerobic conditions in the upper part. Hydric soil indicators are features in the soil that predominantly form by biogeochemical processes in a saturated and anaerobic environment and result in the accumulation of loss of iron, manganese, sulfur, or carbon compounds.
Emily uses a soil auger to collect a sample of the first 6 - 12 inches of soil where the most significant parts of a hydric soil would be occurring.
Once Ivy and Emily identify that the soil is indeed hydric, Ivy uses her Munsell soil color book to determine the value of the soil and each hydric soil indicator.
They also document additional characteristics of each soil layer: Is it loam, silty loam, sand, sandy loam, silt, muck, clay, clayey loam, etc.? What is the percentage of rocks, plant roots, or other organic matter in each layer? What is the percentage of redoximorphic features of each layer and are they faint or prominent?
Each layer of the soil profile, which is typically documented to a depth of at least 18 inches, is sectioned out and thoroughly described.
The identification of positive indicators of wetland hydrology includes direct observation of indicator groups, such as the observation of surface water or saturated soils, evidence of recent inundation, evidence of current or recent soil saturation, and evidence from other site conditions or data. Each group contains several indicators, which are classified into categories known as “primary” or “secondary” indicators.
To positively identify the area as being a wetland, at least one primary wetland indicator (from any group) or at least two secondary wetland indicators (from any group) must be present.
Additionally, for an area to be designated as a wetland, the area must have the presence of water for a week or more during the growing season. Areas with wetland hydrology characteristics are those where the presence of water has an overriding influence on characteristics of vegetation and soils due to anaerobic and reducing conditions, respectively.
Today, Emily and Ivy observe a depression (secondary) along with a few inches of standing water (primary), water-stained leaves (primary), frogs hopping around (primary), and moss trim lines on the tree trunks (secondary). All signs point to a forested wetland; however, there is more to consider.
Ivy and Emily’s soil boring assessment showed that the soils within the top 12 inches of the soil surface were saturated (primary) and bright orange streaks were visible along the plant roots, which they documented as oxidized rhizospheres along living roots (primary). Because they identified more than one primary and two secondary wetland indicators, they can confidently delineate the wetland.
Now that Ivy and Emily established that a wetland is present, they must find the boundary of the upland. They are now looking for the absence of hydrophytic vegetation, hydric soils, and positive indicators of wetland hydrology as well as the dominance of upland ecological plant communities. The same analysis and documentation process they completed for the wetland area is also required for the upland area.
Once they locate the boundary, they flag the wetland line, labeling the flagging with the wetland nomenclature and either hanging it or pinning it into the ground.
While the description sounds relatively simple, finding the boundary between a wetland and upland can be tricky and time consuming. For example, there may be some hydrophytic vegetation growing within an upland and there may be one secondary positive indicator of wetland hydrology, but hydric soils are missing. To positively classify an area as a wetland, a slam dunk on all three parameters is required.
Ivy and Emily must also delineate waterbodies concurrent with wetlands. Waterbodies may include, but are not limited to, streams, rivers, lakes, and ponds. To delineate a waterbody, they hang labeled flagging along the waterbody’s top of bank or its ordinary high water mark. Throughout this process, they take pictures to document the existing waterbody conditions.
Once the wetland delineation is complete, Ivy and Emily draw out a field sketch that depicts the approximate extent and location of the wetland and waterbody boundaries with their respective nomenclature.
Depending on the project scope, the field sketch is either submitted to a Professional Licensed Surveyor who will then visit the site to survey each wetland and waterbody flag, or Ivy and Emily will return to the site to survey each flag with a survey-grade GPS. Once the survey is complete, Ivy and Emily will conduct a final review of the plans to ensure accuracy.
If requested, they will also prepare a wetland delineation report, which outlines the delineation method, findings, results, and thorough description of each wetland and its soils, hydrology, and vegetation.
“Wetland delineations aren’t for the faint of heart,” said Ivy. “At the end of the day, you might emerge from a dense stand of Phragmites garnering strange looks from passersby with muck smeared on your face, sticks and leaves poking out of your hair, a belly full of mosquitos that you might have accidentally swallowed, and fingernails stuffed with dirt. However, there isn’t any other type of field that I would rather be in. As a wetland delineator, I can access environments that most people would steer clear of and, as a result, I get to see things that I wouldn’t get to see anywhere else. I get to improve my plant identification skills and expand my knowledge of how wetlands function as an ecosystem.”
Emily Bjorhus 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. Mrs. Bjorhus is a certified Professional Wetland Scientist.
As an Environmental Scientist, Ivy Babson regularly conducts wetland delineations and monitoring, flora/fauna surveys, water quality sampling, fishery surveys, permitting, and regulatory compliance for a series of projects. She earned her Wetland Delineation Certification from Rutgers University. Ivy graduated from the University of Vermont in 2019 with a B.S. in Environmental Science with a concentration in Ecological Design, and minor in Geospatial Technologies.
Liberty State Park is located on the west bank of Upper New York Bay and is one of the most visited state parks in the nation with over 5.1 million visitors. Princeton Hydro was contracted by U.S. Army Corps of Engineers (USACE) in partnership with the New Jersey Department of Environmental Protection (NJDEP) Office of Natural Resource Restoration (ONRR) to design a resilient coastal ecosystem within 235 acres of this highly urbanized setting that provides both ecological and social benefits. This includes the restoration of over 80 acres of tidal and non-tidal wetlands and creation of several thousands of feet of intertidal shoreline and shallow water habitat hydrologically connected to the Upper New York Bay. When constructed, this will be one of the largest ecosystem habitat restoration projects in New Jersey.
NJDEP held an open house on May 24, 2023 at Liberty State Park announcing the next steps for the Revitalization Program. During the open house, Environmental Protection Commissioner Shawn M. LaTourette and USACE Colonel Matthew W. Luzzatto shared details of the multi-phase revitalization program for the park.
The public was presented with a video that showcases detailed engineering design renderings and simulates the expected visitor experience. The video was created using renderings by Princeton Hydro's Landscape Architect Cory Speroff PLA, ASLA, CBLP and produced in-house by our Marketing & Communications Department in collaboration with NJDEP ONRR. Watch it now:
Once constructed, this project will expand public access, improve water quality, restore native plant communities, and improve coastal resilience for urban communities who are vulnerable to storm events. The site design includes a trail network for the park interior that will provide access to the newly established habitat zones and views of the Statue of Liberty and New York City skyline. This trail network will enhance pedestrian connectivity between the existing portion of Liberty State Park, Liberty Science Center, Jersey City, and local public transit hubs.
Project partners for the interior restoration design include USACE, NJDEP ONRR, National Oceanic and Atmospheric Administration, U.S. Fish and Wildlife Service, National Fish and Wildlife Foundation, HDR, and Princeton Hydro.
Over the next year, NJDEP will provide the community with updates on revitalization program activities, which will include multiple points of continued public engagement and opportunities for community input to inform further design work. The initial groundbreaking is anticipated to take place in Fall 2023.
Please stay tuned to our blog for more project updates. To read more about Princeton Hydro’s robust natural resource management and restoration services, click here.
Just 50 miles southeast of New York City, tucked between two municipalities, sits a 650+ acre tidal salt marsh which spans the shorelines of the South River in densely populated, highly developed Central New Jersey. The South River is the first major tributary of the Raritan River, located 8.3 miles upstream of the Raritan River’s mouth, which drains into Raritan Bay.
The Lower Raritan River and Raritan Bay make up a large part of the core of the NY-NJ Harbor and Estuary Program. Within the Raritan Estuary, the South River wetland ecosystem is one of the largest remaining wetland complexes. While the South River salt marsh ecosystem has been spared from direct development, it has been degraded in quality, and does not provide optimal habitat for wildlife or maximum flood protection for residents. This area is subject to fairly regular tidal flooding (particularly when it occurs simultaneously with a storm) and periodic—generally more severe—flooding during more significant events such as nor’easters and tropical storms. Hurricanes Irene and Sandy caused damage in the Boroughs of Sayreville and South River too.
In 2018, Princeton Hydro and Rutgers University, along with the Lower Raritan Watershed Partnership, Middlesex County, Borough of Sayreville, Borough of South River, NY/NJ Baykeeper, Raritan Riverkeeper, and the Sustainable Raritan River Initiative, secured funding from NFWF’s National Coastal Resilience Fund for the “South River Ecosystem Restoration & Flood Resiliency Enhancement Project.”
The South River Ecosystem Restoration and Flood Resiliency Enhancement Project aims to:
Reduce socioeconomic damages to the Boroughs of South River and Sayreville caused by storm damage, flooding, and sea level rise;
Transform degraded wetlands to high-quality marsh that can reduce flooding and enhance fish & wildlife habitat; and
Engage stakeholders in activities about coastal resilience and ecological health to maximize public outreach in the Raritan River Watershed.
For this 165-acre tidal marsh and transitional forest “eco-park,” the project team is conducting an ecosystem restoration site assessment and design. This phase of the coastal restoration project will result in a permit-ready engineering design plan that stabilizes approximately 2.5 miles of shoreline, reduces flood risk for smaller coastal storms, and enhances breeding and foraging habitat for 10 state-listed threatened and endangered avian species.
This area has experienced repeated flooding, especially during large storms. For example, coastal areas of Sayreville and South River flooded after Hurricane Floyd (1999), Tropical Storm Ernesto (2006), Hurricane Irene (2011), and Hurricane Sandy (2012). Over the last century, there have been several studies and assessments completed for the South River, many of which identify this project area as a priority location for flooding improvements. The following are key reports and studies published about the project area and surrounding communities:
NJ Legislature’s 71st Congress published a report, “Basinwide Water Resource Development Report on the Raritan River Basin” which focused on navigation and flood control for the entire Raritan River Basin. It discussed recommendations for flood control and local storm drainage, setting the stage for future actions.
NJDEP Division of Water Resources published Flood Hazard Reports for the Matchaponix Brook System and Raritan River Basin, which delineated the floodplains in the South River, and its tributaries, the Manalapan Brook and Matchaponix Brook.
USACE New York District released a “Survey Report for Flood Control, Raritan River Basin,” which served as a comprehensive study of the Raritan River Basin and recommended several additional studies. Although the South River was studied, none of the proposed improvements were determined to be economically feasible at that time.
Project area was listed as one of the Nation’s Estuaries of National Significance.
USACE conducted a multi-purpose study of this area. This preliminary investigation identified Federal interest in Hurricane and Storm Damage Reduction and ecosystem restoration along the South River and concluded that a 100-year level of structural protection would be technically and economically feasible.
USACE NYD and NJDEP released a joint draft, “Integrated Feasibility Report and Environmental Impact Statement” for the South River, Raritan River Basin, which focused on “Hurricane & Storm Damage Reduction and Ecosystem Restoration.” Because it was previously determined that there were no widespread flooding problems upstream, the study area was modified to focus on the flood-prone areas within the Boroughs of Sayreville and South River, as well as Old Bridge Township.
Through collaboration with our project partners and following input provided from a virtual stakeholder meeting held in December 2020, Princeton Hydro developed a conceptual design for an eco-park that incorporates habitat enhancement and restoration, and protective measures to reduce impacts from flooding while maximizing public access and utility. Public access includes trails for walking and designated areas for fishing. The eco-park can also be used for additional recreation activities such as bird watching and kayaking.
Highlights of the conceptual design include the following features:
Approximately two miles of trails with overlook areas, connection to fishing access, and a kayak launch.
~3,000 linear feet of living shoreline, located along portions of the Washington Canal and the South River, to provide protection from erosion, reduce the wake and wave action, and provide habitat for aquatic and terrestrial organisms.
~60 acres of enhanced upland forest to provide contiguous habitat areas for resident and migratory fauna.
A tidal channel that will connect to the existing mud flat on the southeastern part of the site and provide tidal flushing to proposed low and high marsh habitats along its banks.
A vegetated berm with a trail atop will extend the length of the site to help mitigate flood risk.
Two nesting platforms for Osprey, a species listed as “Threatened” in NJ
Designated nesting habitat for the Diamondback Terrapin, a species listed as “Special Concern” in NJ
Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of ecological rehabilitation and floodplain management projects. Click here to read about a coastal rehabilitation and resiliency project we completed in New Jersey.
As part of the multi-faceted effort to restore the vital Hudson River ecosystem, the USACE New York District launched the Hudson River Habitat Restoration. Princeton Hydro led the Hudson River Habitat Restoration Integrated Feasibility Study and Environmental Assessment for USACE. For this project, we established and evaluated baseline conditions through data collection and analysis; developed restoration objectives and opportunities; prepared an Environmental Assessment; and designed conceptual restoration plans for eight sites.
This week, Lt. Gen. Scott A. Spellmon, USACE Commanding General and 55th U.S. Army Chief of Engineers, signed the Hudson River Habitat Restoration Ecosystem Restoration Chief’s Report, which represents the completion of the study and makes it eligible for congressional authorization.
As stated in the USACE-issued news release, “The Chief’s Report recommends three individual ecosystem restoration projects including Henry Hudson Park, Schodack Island Park, and Moodna Creek within the 125-mile study area from the Federal Lock and Dam at Troy, NY to the Governor Mario M. Cuomo Bridge. These projects would restore a total of approximately 22.8 acres of tidal wetlands, 8.5 acres of side-channel and wetland complex, and 1,760 linear feet of living shoreline with 0.6 acres of tidal wetlands. The plan would also reconnect 7.8 miles of tributary habitat to the Hudson River through the removal of 3 barriers along Moodna Creek.”
“The signing of this Chief’s Report is a significant milestone for the HRHR Project,” said Col. Matthew Luzzatto, USACE New York District Commander. “This has truly been a team effort and I want to thank our non-federal sponsors, New York State Department of Environmental Conservation and New York State Department of State, and all of our engineers, scientists, and partners at the local, state and federal level for their unwavering support.”
Read the full press release here. And, for more background information on the Feasibility Study and proposed restoration work, check out our original blog post:
Non-native Phragmites australis, also known as Common Reed, is a species of perennial grass found across North America, especially along the Atlantic coast, in wetlands, riparian areas, shorelines, and other wet areas like roadside ditches and drainage basins. This aggressively invasive grass can grow up to 20 feet tall, in dense groupings, and tends to spread rapidly, quickly colonizing disturbed wetlands.
Once established, the invasive plant forms a monoculture with a dense mat, outcompeting native vegetation, lowering the local plant biodiversity, and displacing native animals. These landscape changes impair the natural function of the marsh ecosystem by altering its elevations and tidal reach. A higher, drier marsh leads to less vigorous growth of native salt marsh vegetation, allowing Phragmites australis to gain a stronger foothold and continue to take over.
Phragmites australis can also eliminate small, intertidal channels and obliterate pool habitat that offers natural refuge and feeding grounds for invertebrates, fish, and birds. The spread of invasive Phragmites australis also has negative impacts on land aesthetics and outdoor recreation by obscuring views and restricting access. And, each Fall, when Phragmites australis die off, the large concentrations of dry vegetation increase the risk of fast-spreading fires near highly populated residential and commercial areas.
Over the last century, there has been a dramatic increase in the spread of Phragmites australis, partly due to an increase in residential and commercial development that resulted in disturbances to wetlands. According to the U.S. Fish and Wildlife Service, the rapid spread of Phragmites australis in the 20th century can also be attributed to the construction of railroads and major roadways, habitat disturbance, shoreline development, pollution, and eutrophication.
Princeton Hydro has worked in areas throughout the East Coast to address and properly manage Phragmites australis in order to restore natural habitats and enhance plant diversity, wildlife habitat, and water quality. Two recent projects include the restoration of John A. Roebling Memorial Park in Hamilton and Pin Oak Forest Conservation Area in Woodbridge, New Jersey.
Mercer County’s John A. Roebling Memorial Park is home to the northernmost freshwater tidal marsh on the Delaware River, the Abbott Marshlands, an area containing valuable habitat for many rare species. Unfortunately, the area experienced a significant amount of loss and degradation, partially due to the introduction of the invasive Phragmites australis.
For Mercer County Park Commission, Princeton Hydro put together a plan to reduce and control the Phragmites australis, in order to increase biodiversity, improve recreational opportunities, and enhance visitor experience at the park. This stewardship project replaced the Phragmites australis with native species in order to reduce its ability to recolonize the marsh.
By Spring of this year, the team expects to see native species dominating the landscape from the newly exposed native seed bank with minimal Phragmites australis growth.
The Pin Oak Forest Conservation Area is a 97-acre tract of open space that contains an extremely valuable wetland complex at the headwaters of Woodbridge Creek. The site is located in a heavily developed landscape of northern New Jersey. As such, the area suffered from wetland and stream channel degradation, habitat fragmentation, ecological impairment, and decreased biodiversity due to invasive species, including Phragmites australis.
The site was viewed as one of only a few large-scale freshwater wetland restoration opportunities remaining in this highly developed region of New Jersey. A dynamic partnership between government agencies, NGOs, and private industry, was formed to restore the natural function of the wetlands complex, transform the Pin Oak Forest site into thriving habitat teeming with wildlife, and steward this property back to life.
This award-winning restoration project converted over 30 acres of degraded freshwater wetlands, streams and disturbed uplands dominated by invasive species into a species-rich and highly functional headwater wetland complex. The resulting ecosystem provides valuable habitat for wildlife including the state-threatened Black-crowned Night-heron and Red-headed Woodpecker. Biodiversity was also increased through invasive species management, which allowed establishment of native plants such as pin oak, swamp white oak, marsh hibiscus, and swamp rose. The restored headwater wetland system provides stormwater management, floodplain storage, enhanced groundwater recharge onsite, and surface water flows to Woodbridge Creek, as well as public hiking trails, all benefiting the town of Woodbridge.
Scientific field research continues to be conducted in order to identify the best way(s) to manage and control the spread of Phragmites australis. Depending on the landscape and how established the Phragmites australis population is, there are several different methods that can be effective in reducing Phragmites australis infestations in order to allow for the regeneration of native wetland plant communities and protect fish and wildlife habitat.
Recently, a group of more than 280 scientists, resource managers and policy professionals gathered together at the Hudson River Estuary Program’s (HEP) annual conference to explore how natural and nature-based solutions (i.e. building living shorelines, enhancing tidal wetlands and stream corridors, and conserving vulnerable floodplains) can be used as critical tools for addressing the impacts of climate change while also protecting and enhancing critical habitat.
The conference included six interactive workshops and dynamic panel discussions. Christiana Pollack, CERP, GISP, CFM of Princeton Hydro, Terry Doss of New Jersey Sports and Exposition Authority, Kip Stein from New York City Parks, and Judith Weis of Rutgers lead a panel discussion, moderated by Lisa Baron from U.S. Army Corps Engineers, on "The Yin and Yang of Estuarine Phragmites Management" to share lessons learned over many years of combating invasive species, including how sea level rise is changing minds and techniques.
Together, representing decades of experience in Phragmites australis management and research, these experts presented the evolving nature of restoration for this habitat type, common control/management methodologies, and long-term management and monitoring strategies for this reed and other invasive species. During the panel discussion, Christiana made specific mention of the Roebling Park project as one example of successful strategies in action.
If you’re interested in learning more and seeing photos from a few recent Phragmites australis management projects, click below for a free download of Christiana’s full presentation.
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. Click here to learn more about how invasive species disrupt our ecosystems, why managing them is so important, and the cutting-edge tools and innovative techniques helping to eradicate invasives and restore balance to delicate ecosystems.
The Hudson River originates at the Lake Tear of the Clouds in the Adirondack Mountains at an elevation of 4,322 feet above sea level. The river then flows southward 315 miles to New York City and empties into the New York Harbor leading to the Atlantic Ocean. The Hudson River Valley lies almost entirely within the state of New York, except for its last 22 miles, where it serves as the boundary between New York and New Jersey.
Approximately 153 miles of the Hudson River, between the Troy Dam to the Atlantic Ocean, is an estuary. An estuary is defined by the USEPA as “a partially enclosed, coastal water body where freshwater from rivers and streams mixes with salt water from the ocean. Estuaries, and their surrounding lands, are places of transition from land to sea. Although influenced by the tides, they are protected from the full force of ocean waves, winds and storms by landforms such as barrier islands or peninsulas.”
The Hudson River’s estuary encompasses regionally significant habitat for anadromous fish and globally rare tidal freshwater wetland communities and plants, and also supports significant wildlife concentrations. As a whole, the Hudson River provides a unique ecosystem with highly diverse habitats for approximately 85% of New York State’s fish and wildlife species, including over 200 fish species that rely on the Hudson River for spawning, nursery, and forage habitat.
The Hudson is an integral part of New York’s identity and plays a vital role in the lives of the people throughout the area. Long valued as a transportation corridor for the region’s agricultural and industrial goods, and heavily used by the recreation and tourism industries, the Hudson plays a major role in the local economy. It also provides drinking water for more than 100,000 people.
At the end of the American Revolution, the population in the Hudson River Valley began to grow. The introduction of railroad travel in 1851 further accelerated development in the area. Industrial buildings were erected along the river, such as brick and cement manufacturing, which was followed by residential building. Along with the aforementioned development, came the construction of approximately 1,600 dams and thousands of culverts throughout the Hudson River.
According to the U.S. Army Corps of Engineers (USACE), these human activities have significantly degraded the integrity of the Hudson River ecosystem and cumulatively changed the morphology and hydrology of the river. Over time, these changes have resulted in large-scale losses of critical shallow water and intertidal wetland habitats, and fragmented and disconnected habitats for migratory and other species. Most of this loss and impact has occurred in the upper third portion of the estuary.
As part of the effort to restore the vital river ecosystem, the USACE New York District launched a Hudson River Habitat Restoration Feasibility Study, which helps to establish and evaluate baseline conditions, develop restoration goals and objectives, and identify key restoration opportunities. Princeton Hydro participated in data collection and analysis, conceptual restoration designs, and preparation of the USACE Environmental Assessment for the Hudson River Habitat Restoration Ecosystem Restoration Draft Integrated Feasibility Study and Environmental Assessment.
The study area includes the Hudson River Valley from the Governor Mario M. Cuomo Bridge downstream to the Troy Lock and Dam upstream. The primary restoration objectives include restoring a mosaic of interconnected, large river habitats and restoring lost connectivity between the Hudson River and adjacent ecosystems.
A total of six sites were evaluated using topographic surveys, installation and monitoring of tide gauges, evaluation of dam and fish barrier infrastructure, and field data collection and analysis to support Evaluation of Planned Wetlands (EPW) and Habitat Suitability Indices (HSI) functional assessment models. Literature reviews were also completed for geotechnical, hazardous toxicity radioactive waste, and aquatic organism passage measures.
Multiple alternatives for each of the six sites were created in addition to the preparation of conceptual designs, quantity take-offs, and cost estimates for construction, monitoring and adaptive management, and long-term operation and maintenance activities.
Princeton Hydro also prepared an environmental assessment in accordance with NEPA standards, addressing all six sites along the Hudson River and its tributaries. This assessment served to characterize existing conditions, environmental impacts of the preferred Proposed Action and No Action Alternatives, and regional cumulative environmental impacts. Our final report was highlighted by USACE at the 2019 Planning Community of Practice (PCoP) national workshop at the Kansas City District as an example of a successfully implemented Ecosystem Restoration Planning Center of Expertise (ECO-PCX) project.
USACE’s specific interest in Hudson River restoration stems from the aforementioned dramatic losses of regional ecosystems, the national significance of those ecosystems, and the apparent and significant opportunity for measurable improvement to the degraded ecological resources in the river basin.
The feasibility study is among the first of several critical steps in restoring the Hudson River’s ecosystem function and dynamic processes, and reestablishing the attributes of a natural, functioning, and self-regulated river system. Stay tuned for more updates on the Hudson River restoration efforts.
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