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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. [gallery link="none" ids="13801,13803,13812"] 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. [embed]https://youtu.be/XbzQ08o7b5Y[/embed] Following the groundbreaking, the public was invited to see and comment on renderings of Phase 1B, which includes active recreation components such as athletic fields, an amphitheater, a skate park, and a community center. [gallery link="none" columns="2" ids="13805,13806,13798,13804,13813,13802,13810,13809"] To learn more about this project, click here to read our recent blog post, titled "Restoring 235 Acres in NJ's Iconic Liberty State Park." [post_title] => Reclaiming Liberty State Park: A Historic Groundbreaking Event [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => reclaiming-liberty-state-park-a-historic-groundbreaking-event [to_ping] => [pinged] => [post_modified] => 2023-10-24 01:39:46 [post_modified_gmt] => 2023-10-24 01:39:46 [post_content_filtered] => [post_parent] => 0 [guid] => https://princetonhydro.com/?p=13796 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 5787 [post_author] => 3 [post_date] => 2023-07-10 05:16:11 [post_date_gmt] => 2023-07-10 05:16:11 [post_content] => 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: [embed]https://youtu.be/XbzQ08o7b5Y[/embed] 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. [post_title] => Restoring 235 Acres in NJ's Iconic Liberty State Park [post_excerpt] => [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => liberty-state-park-2023 [to_ping] => [pinged] => [post_modified] => 2025-07-22 12:19:48 [post_modified_gmt] => 2025-07-22 12:19:48 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.princetonhydro.com/blog/?p=883 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 1 [filter] => raw ) [2] => WP_Post Object ( [ID] => 9512 [post_author] => 1 [post_date] => 2021-09-25 04:11:00 [post_date_gmt] => 2021-09-25 04:11:00 [post_content] => 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:
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.
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:
Highland Falls, New York, which is 40 miles north of Manhattan, stretches along the Hudson River and is populated by many lakes and ponds, including the Cragston Lakes (a.k.a. Lower Cragston). For the community’s 4,000 residents, living in an area where water is abundant has many benefits, but the benefits are not without flood risk.
The 9-acre Lower Cragston Lake, the second largest lake in the Highland Falls area, contains the Lower Cragston Dam, which is owned by the United States Military Academy at West Point and managed through the U.S. Army Corps of Engineers New York District (USACE NYD). According to the Office of the New York State Comptroller, Lower Cragston Dam is classified as a “High Hazard” dam. The dam is approximately 10 feet high and 210 feet long, and consists of an earthen embankment with a concrete core wall, a concrete ogee spillway, and a low level outlet.
In order to ensure safety to the surrounding community and mitigate any potential flood risk associated with the dam's operations, Princeton Hydro was contracted by the USACE NYD to perform an Engineering Assessment for Lower Cragston Dam. Engineering Assessments and periodic safety inspections are intended to provide an independent review of an existing dam structure to ensure that all components are functioning properly and in compliance with current dam safety regulations.
Princeton Hydro utilized a multidisciplinary approach to perform the Lower Cragston Dam Engineering Assessment, which consisted of:
The geotechnical investigation for the Lower Cragston Dam Engineering Assessment involved performing soil borings and rock coring within the dam embankment, for which Princeton Hydro developed a Drilling Program Plan (DPP) to ensure the activities were performed successfully and safely. The DPP, which also required our team to have a comprehensive understanding of bedrock and surficial geologic formations in the area, was ultimately approved by the USACE Dam Safety Officer and successfully executed in the field. The collected samples were tested at Princeton Hydro’s AASHTO-accredited and USACE-validated soil laboratory.
Ultimately, the geotechnical investigation and subsequent soil analysis were used to inform the slope stability and seepage analysis. The geotechnical analyses, hydrologic & hydraulic study, structural inspection, bathymetry, and dam break analysis were used to provide USACE and West Point with recommendations for repair options, replacement options, and decommissioning options for the dam.
Engineering Assessments are vital to the longevity of dams and the safety of the communities they protect. By providing detailed analysis, effective repair, and management programs can be designed and implemented efficiently. This helps to ensure dam systems are providing the level of protection they were designed to deliver.
Princeton Hydro has designed, permitted, and overseen the reconstruction, repair, and removal of dozens of small and large dams. Our Geoscience and Water Resources Engineering teams perform dam inspections and conduct dam feasibility studies throughout the Northeast. For more info, click here.
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Hydrology is the study of the properties, distribution, and effects of water on the Earth’s surface, in the soil and underlying rocks, and in the atmosphere. The hydrologic cycle includes all of the ways in which water cycles from land to the atmosphere and back. Hydrologists study natural water-related events such as drought, rainfall, stormwater runoff, and floods, as well as how to predict and manage such events. On the application side, hydrology provides basic laws, equations, algorithms, procedures, and modeling of these events.
Hydraulics is the study of the mechanical behavior of water in physical systems. In engineering terms, hydraulics is the analysis of how surface and subsurface waters move from one point to the next, such as calculating the depth of flow in a pipe or open channel. Hydraulic analysis is used to evaluate flow in rivers, streams, stormwater management networks, sewers, and much more.
Combined hydrologic and hydraulic data, tools, and models are used for analyzing the impacts that waterflow - precipitation, stormwater, floods, and severe storms - will have on the existing infrastructure. This information is also used to make future land-use decisions and improvements that will work within the constraints of the hydrologic cycle and won’t exacerbate flooding or cause water quality impairment.
Simply put, hydrologic and hydraulic modeling is an essential component of any effective flood risk management plan.
Eastwick, a low-lying urbanized neighborhood in Southwest Philadelphia, is located in the Schuylkill River Watershed and is almost completely surrounded by water: The Cobbs and Darby creeks to the west, the Delaware River and wetlands to the south, and the Schuylkill River and Mingo Creek to the east. The community is at continual risk of both riverine and coastal flooding, and faces an uncertain future due to sea level rise and riverine flooding exacerbated by climate change.
Princeton Hydro, along with project partners KeystoneConservation and University of Pennsylvania, conducted an analysis of Eastwick, the flood impacts created by the Lower Darby Creek, and the viability of several potential flood mitigation strategies.
Flood mitigation approaches can be structural and nonstructural. Structural mitigation techniques focus on reconstructing landscapes, including building floodwalls/seawalls and installing floodgates/levees. Nonstructural measures work to reduce damage by removing people and property out of risk areas, including zoning, elevating structures, and conducting property buyouts.
For Eastwick, studying stream dynamics is a key component to determining what type of flood mitigation strategies will yield the most success, as well as identifying the approaches that don’t work for this unique area.
Princeton Hydro’s study focused on the key problem areas in Eastwick: the confluence of Darby Creek and Cobbs Creek; a constriction at Hook Road and 84th Street; and the Clearview Landfill, which is part of the Lower Darby Creek Superfund site. Additionally, the study sought to answer questions commonly asked by community members related to flooding conditions, with the main question being: What impact does the landfill have on area flooding?
The built-up landfill is actually much higher than the stream bed, which creates a major disconnection between the floodplain and the stream channel. If the landfill didn’t exist, would the community still be at risk? If we increased the floodplain into the landfill, would that reduce neighborhood flooding?
Princeton Hydro set out to answer these questions by developing riverine flooding models primarily using data from US Army Corps of Engineers (USACE), Federal Emergency Management Agency (FEMA), The National Oceanic and Atmospheric Administration (NOAA), and NOAA's National Weather Service (NWS). FEMA looks at the impacts of 1% storms that are primarily caused by precipitation events as well as coastal storms and storm surge. NOAA looks at the impacts of hurricanes. And, NOAA's NWS estimates sea, lake and overland storm surge heights from hurricanes.
The models used 2D animation to show how the water flows in various scenarios, putting long-held assumptions to the test.
The models looked at several different strategies, including the complete removal of the Clearview Landfill, which many people anticipated would be the silver bullet to the area’s flooding. The modeling revealed, however, that those long-held assumptions were invalid. Although the landfill removal completely alters the flood dynamics, the neighborhood would still flood even if the landfill weren’t there. Additionally, the modeling showed that the landfill is actually acting as a levee for a large portion of the Eastwick community.
Ultimately, the research and modeling helped conclude that for the specific scenarios we studied, altering stream dynamics – a non-structural measure – is not a viable flood mitigation strategy.
The USACE is currently undergoing a study in collaboration with the Philadelphia Water Department to test the feasibility of a levee system (a structural control measure), which would protect the Eastwick community by diverting the flood water. Funding for the study is expected to be approved in the coming year.
There are many studies highlighting flood mitigation strategies, environmental justice, and climate change vulnerability in Eastwick. Princeton Hydro Senior Project Manager and Senior Ecologist, Christiana Pollack CFM, GISP, presented on the flooding in Eastwick at the Consortium for Climate Risk in the Urban Northeast Seminar held at Drexel University. The seminar also featured presentations from Michael Nairn of the University of Pennsylvania Urban Studies Department, Ashley DiCaro of Interface Studios, and Dr. Philip Orton of Stevens Institute of Technology.
For more information about Princeton Hydro’s flood management services, go here: http://bit.ly/PHfloodplain.
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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