Engineering Assessment of West Point’s Lower Cragston Dam

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:

  • Document Review: In order to understand the site and to develop a proper drilling scope and methodology, our team conducted a thorough review of existing documentation, including historic engineering plans, dam inspection reports, and an Emergency Action Plan.
  • Geotechnical and Geophysical Investigation and Reporting: This is one of the most significant aspects of a dam safety evaluation and is often the most efficient means of obtaining critical subsurface information. The information obtained from these field studies is used to devise safety improvements if determined to be necessary.
  • Bathymetric and Topographic Survey: The bathymetric survey entails the accurate mapping of water depths and the quantification of the amount of accumulated, unconsolidated sediment. The topographic survey looks at the height, depth, size, and location of the dam and surrounding area.
  • Hydrologic & Hydraulic Analysis: This analysis looks at the watershed and spillway structure related to the extent of potential flooding from storm recurrence intervals within the study area. The data helps to evaluate measures that can reduce and mitigate existing and anticipated flood risk.
  • Structural Analysis: Our team utilized various methods, to assess the structural integrity of the dam and to evaluate the internal stresses and stability under usual, unusual, and extreme loading combinations.
  • Seepage & Stability Analysis: Seepage through an earthen dam generally correlates with the reservoir water level of the dam. A careful analysis helps to detect any abnormal seepage issues and associated consequences.
  • Dam Break Analysis: This type of analysis is used to estimate the potential hazards associated with a failure of the dam structure and features.

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, visit: bit.ly/PHEngineering.

After 100 Years, Fish Passage is Restored at Critical Migratory Fish Spawning Grounds in NJ

Photo by the American Littoral SocietyFor over 100 years, the Old Mill Pond Dam in Spring Lake Heights, New Jersey has blocked critical anadromous fish species from reaching optimal spawning habitat. Today, we are thrilled to announce that, thanks to a fish ladder installed by the American Littoral Society (ALS), migratory fish can now scale the dam and access upstream spawning grounds.

The 60-foot-long fish ladder is a device that allows a channel of water to flow through it and is engineered to create both the proper water depth and velocity for fish to navigate through. In this case, it will enable fish to scale the 10-foot-high dam and go deeper into Wreck Pond Brook.

This video from ALS provides an up-close look at the Alaska-Steeppass Fish Ladder and more details about the project:

Re-opening river passage for migratory species improves not only the health of Wreck Pond Brook and its watershed, but it also benefits the overall ecosystem of the Atlantic shoreline and its coastal rivers. It also supports important recreational and commercial species, such as cod, haddock, and striped bass, which leads to a healthier economy.

For over a century, the dam blocked anadromous fish like Alewife and Blueback river herring, from entering the Wreck Pond Brook Watershed. These fish spend most of their lives in the ocean but need freshwater in order to spawn. The Old Mill Pond Dam, an impassable obstruction for these migrating fish, was identified as a key contributor to the decline of Atlantic coast river herring populations. Subsequently, river herring were classified as National Oceanic and Atmospheric Administration (NOAA) Species of Special Concern and identified as requiring Concentrated Conservation Actions.

Design rendering provided by the American Littoral SocietyThe fish ladder, which was funded through the US Fish and Wildlife Service and implemented by ALS along with a variety of project partners, including Princeton Hydro, is one more major step in the ongoing effort to restore critical migratory fish spawning grounds, support a vibrant food web to the area, and rehabilitate Wreck Pond and its watershed.

According to the ALS, “Now, instead of Old Mill Dam acting as the furthest migration destination for Alewife and Blueback river herring, these fish have the ability to navigate up the dam through the fish ladder and utilize roughly an additional mile of optimal spawning habitat. The ALS will add the Old Mill Dam fish ladder and newly accessible spawning habitat into its ongoing river herring monitoring surveys.”

American Littoral Society promotes the study and conservation of marine life and habitat, protects the coast from harm, and empowers others to do the same. Learn more and get involved: littoralsociety.org.

Princeton Hydro has designed, permitted, and overseen solutions for fish passage including the installation of technical and nature-like fishways and the removal of dozens of small and large dams throughout the Northeast. To learn more about our fish passage and dam removal engineering services, visit: bit.ly/DamBarrier.

Images provided by the American Littoral Society. 

Photo by the American Littoral Society

FREE DOWNLOADS: Mid-Atlantic Stream Restoration Conference Presentations

The Resource Institute hosted its 9th Annual Mid-Atlantic Stream Restoration Conference in Baltimore, Maryland, where water resource professionals, researchers, and practitioners come together for three days to share ideas and learn about stream restoration planning, assessment, design, construction, evaluation, and other topical stream issues. The conference, which was themed Building Resilient Streams in the Mid-Atlantic and Northeast regions, included presentations, discussions, exhibits, and pre-conference workshops. Princeton Hydro participated in three presentations on a variety of topics. Below, we provide a synopsis and free download of each presentation:

Innovative Design and Funding Approaches for Dam Removal Projects Where an Unfunded Mandate Exists

Lead Presenter: Kirk Mantay, PWS, GreenTrust Alliance, Inc.
Co-Authors: Geoffrey Goll, P.E.; Princeton Hydro President; John Roche, Maryland Department of Environment; and Brett Berkley, GreenVest.

The presentation provides a detailed look at the removal of the Martin Dam in Fallston, Maryland, and how project partners were able to drastically expand the footprint of this emergency dam removal to generate enough ecological restoration benefits to adequately fund the dam removal itself.

The Martin Dam was constructed in 1965 as part of USDA’s sustainable farms pond construction initiative, which promoted aquaculture and subsistence fish production on small farms across the region as an income source for agricultural producers. Dam-related impacts included the permanent loss of spring-fed sedge wetlands, ditching of forested floodplain wetlands, pollution from stream bank entrenchment, and thermal impacts to a wild brook trout population downstream.

Overtime, the dam structure began to degrade. With each state and local agency inspection that was conducted, the dam increased in hazard category. In 2016, the Maryland Department of the Environment (MDE) was forced to list the dam as a, “public safety hazard at risk of immanent failure.” The landowner, unable to fund the dam removal, contacted GreenTrust Alliance (GTA), a regional green infrastructure nonprofit organization, for help.

By emphasizing the ecological benefits of restored wetlands and streams above and below the dam as well as the critical public safety hazard faced by residents and motorists downstream, GTA, in partnership with Princeton Hydro and GreenVest, was able to secure restoration funding for the site. The design and permitting was lead by Princeton Hydro, and the dam was safely breached as part of restoration construction in January 2019.

Learn more and download the full presentation.

 

Columbia Lake Dam Removal; Using Drones for Quantitative Evaluation of River Restoration

Lead Presenter: Beth Styler-Barry of The Nature Conservancy
Co-Authors from Princeton Hydro: Geoffrey Goll, P.E., President; Casey Schrading, EIT, Staff Engineer; Kelly Klein, Senior Project Manager, Natural Resources; and Christiana Pollack, CFM, GISP, Senior Project Manager, Environmental Scientist.

In order to explore the use of drone or UAV technology to evaluate the effects of dam removals, the presentation showcases the Columbia Lake Dam removal, the largest dam removal in New Jersey to date.

The Columbia Lake Dam, built in 1909, was 18 feet high, 330 feet long dam, and stretched more than 1.5 miles on the Paulins Kill less than 0.25 miles upstream from its confluence with the Delaware River. As part of The Nature Conservancy’s (TNC) mission to improve the quality of the Paulins Kill, removing this “first blockage” was the cornerstone of the larger mission. Princeton Hydro served as the engineer-of-record, designing and permitting this project. Dam removal activities commenced in 2018 and were finalized in 2019. Its removal opens 10 miles of river for fish migration and improves recreation access, floodplain reconnection, habitat enhancement and higher water quality.

TNC will conduct five years of monitoring, a vitally important component of this project, to determine long-term ecological uplift, short-term positive and negative effects, and to develop data to provide information for future dam removals. And, as a result of the programmable and repeatable nature of drone flight paths, such monitoring will be able to be conducted for years and decades, producing invaluable data for research and future project design.

The presentation reviews the various parameters investigated, the results and significance of the data retrieved, and recommendations for the use of drone technology for future ecosystem restoration projects.

Learn more and download the full presentation.

Modeling 3D Rivers in AutoCAD to Enhance Design and Deliverables

Lead Presenter: Daniel Ketzer, PE, Princeton Hydro Senior Project Manager, River Restoration
Co-Authors from Princeton Hydro: Eric Daley, Water Resources Engineer; Cory Speroff, MLA, ASLA, CBLP, Landscape Designer; and Sumantha Prasad, PE, ENV SP, Water Resource Engineer

This presentation provides an overview on how to create 3D river models based on geomorphic input to enhance the overall accuracy and quality of a river restoration project.

In river restoration, the proposed geometry of the river channel is the key part of the design. It impacts earthwork, utility conflicts, plan set layout, and many other aspects of the project. In larger projects with reaches measuring thousands of feet and greater, manual grading is extremely time consuming and tedious; and determining the entire implication of the proposed design is difficult to achieve when simply analyzing proposed cross-sections and profiles. To increase efficiency and maintain uniformity throughout the subject reach developing a 3D-surface model of the proposed restoration reduces design time and increases quality. AutoCAD Civil 3D can be used to convert the proposed profiles and cross-sections from a geomorphic design into a 3D surface of the river corridor.

The presentation goes through the key steps that need to be taken and strategic questions that need to be asked when modeling 3D rivers in AutoCAD along with important tips and reminders.

Learn more and download the full presentation.

Stay tuned for our Spring Events Spotlight to learn how you can participate in upcoming environmental events! Click here to read more about Princeton Hydro’s river restoration services.

Fish Passage Restored on the Paulins Kill

A view of where the Columbia Lake Dam used to reside. February 19, 2019. Photo courtesy of Casey Schrading, Staff Engineer, Princeton Hydro

On the Paulins Kill, the 100-year old Columbia Lake Dam has almost been completely removed, and fish passage has been restored!  Since the first cut was executed on the main dam in August, many exciting advances have been made towards restoring the Paulins Kill back to its natural state. Check out the video below, courtesy of the New Jersey Nature Conservancy Volunteer Drone Team. 

Piece by piece, the dam was notched out throughout the fall season and is now completely removed with the exception of the dam apron, the horizontal concrete structure that sits downstream of the dam, and the section of the dam that sits below the riverbed. The part of the dam in the riverbed is now being removed all the way down  to three feet under the ground. The full removal is estimated to be complete by mid-March. In mid-August, the first cut was widened to 80 feet, allowing for better management of high flows during storm events, which had been posing a challenge immediately following the first cut.

In late August, the installation of rock vanes at the Brugler Road Bridge began. Rock vanes are engineered, in-stream structures that help to stabilize a channel while enhancing aquatic habitat and movement.

A generic schematic example of cross vanes, this is not the exact engineering plan for this specific project. Photo courtesy of North Carolina Cooperative Extension.

The rock vanes installed at the Brugler Road Bridge site are cross vanes. Cross vanes consist of a set of boulders angled upstream on a river, with another section of smaller rocks placed upstream. The taller sections of the cross vanes deflect the streamflow away from the banks, decreasing scouring effects. Instead, the flow travels over the rock walls and concentrates down the center of the channel, creating a deep and elongated pool in the middle of the stream.  

Velocities between the notches in the rock vanes were evaluated using a velocity meter in accordance with the design specifications originally proposed. Based on the U.S. Fish and Wildlife Service fish passage design criteria, velocities in the notches could not be greater than 8.25 feet per second. All of the velocity measurements in this rock vane were below the maximum thresholds, ensuring no blockage of fish passage is made through the vanes.

Since the removal of the dam began, vegetative growth from the natural seedbed of the upper impoundment has been observed (see photo below).

In October, scour protection installation commenced at the Warrington Road Bridge site. After the team conducted geotechnical test pits, they discovered that a concrete scour wall that slopes out to the Paulins Kill was present and deep enough to be able to install rock at the necessary depth. They also found that the existing gabions, caged baskets filled with rock or concrete often used to protect against erosion, were intact and could be left in place. The team installed four (4) feet of riprap under and around the bridge in the riverbed and tied it into the existing grade of the banks.

The original notch in the dam was lowered one foot per day starting in mid-December, reducing water surface elevations down to the apron elevation during the month of January.

To accommodate NJ Fish and Wildlife’s request for animal passage under the I-80 bridges, an area of the previously installed riprap on the northwest abutment wall was flattened out and filled in with river cobble. This path will promote wildlife movement under the bridge as opposed to through the existing tunnel.

Currently, rock vanes are being installed under the I-80 bridges specifically to enhance fish passage. These structures vary slightly from the rock vanes at the Brugler Road Bridge site, as they are designed to slow river flow, helping migrating fish travel upstream and traverse a 5-foot elevation difference in the streambed, much like a fish ladder

These rock vanes are more than halfway completed and are on track to be finished in time for fish populations to make full use of them.  The next steps are to finish the demolition of the dam and the construction of the fish passage rock vanes under the I-80 bridges, plant vegetation throughout the upper impoundment, create a recreational trail through the upper impoundment, and plan for fishing and boating access! Stay tuned for more exciting developments on this incredible project.

Thank you to our project partners: The Nature Conservancy, American Rivers, U.S. Fish and Wildlife Service, and NJDEP Division of Fish and Wildlife Service.

Princeton Hydro has designed, permitted, and overseen the reconstruction, repair, and removal of a dozens of small and large dams in the Northeast. To learn more about our fish passage and dam removal engineering services, visitbit.ly/DamBarrier.

Mitigation Milestone Reached at Mattawoman Creek Mitigation Site

Photo courtesy of GreenVest

Mattawoman Creek Mitigation Project will Restore and Protect 80+ Acres of Mattawoman Creek, Chesapeake Bay’s Most Productive Tributary

As one of the Chesapeake Bay’s most productive tributaries and a vital part of Maryland’s natural resources, Mattawoman Creek supports some of the largest populations of finfish, amphibians, and birds in the state. A collaborative team of private and public sector entities have designed the “Mattawoman Creek Mitigation Site” in Pomfret, Charles County, Maryland, an effort that will enhance or create 64+ acres of wetlands and restore nearly 3,800 linear feet of this perennial stream.  With over 28,500 native trees and shrubs to be planted, this mitigation project will result in 80+ acres of continuous, forested wetland with complex and diverse vegetative communities. It is expected to provide a wide array of habitat to resident and transient wildlife, including birds, reptiles, invertebrates, amphibians and rare, threatened and endangered species.

Unique to this project, Mattawoman Creek Mitigation Site is Maryland’s first-ever Umbrella Mitigation Banking Instrument (UMBI) for federal and other government agency use.   A UMBI is the bundling of multiple mitigation banks into one agreement in order to streamline the regulatory approval process, thereby eliminating steps and involving fewer resources. The Maryland UMBI document helps the USAF and other public agencies secure certainty of cost and schedule, facilitate timely permit issuance, and expedite the satisfaction of their permitted requirements for planned capital improvement projects. This approach also maximizes the scale of restoration and resulting land protection and efforts, creating contiguous blocks of habitat with greatly enhanced benefits compared to single, permittee-responsible projects. This precedent was a result of a partnership between United States Air Force (USAF) and Joint Base Andrews (JBA), U.S. Army Corps of Engineers (USACE), Maryland Department of the Environment (MDE), GreenTrust Alliance, GreenVest, and Princeton Hydro.

Projects completed under the UMBI will reduce federal and state workload expediting the regulatory review and issuance of permits by the MDE and USACE. Additionally, projects completed under this UMBI will aid in compliance with the Federal Paperwork Reduction Act where federal regulatory staff can evaluate success and performance issues for multiple permittees at one single habitat restoration or mitigation site. In addition, federal costs are capped, and liabilities  are transferred through to GreenVest, the private sector operator, and GreenTrust Alliance, the nonprofit bank sponsor, who will also serve as the long-term steward of sites restored under this program.

Pictured is the southern restoration area after
sorghum germination, prior to wetland creation
and reestablishment.
A function-based stream assessment was
performed on the degraded channel.

 

Photo courtesy of GreenVestDesign, engineering/modeling, and permitting of the site was completed by  Princeton Hydro and GreenVest under our currently Ecosystem Restoration contract with the USACE. Princeton Hydro also provided an Environmental Assessment and Environmental Baseline Survey, and conducted a geotechnical investigation, which included the advancement of test pits, visual and manual investigation techniques and logging, infiltration testing, laboratory soils testing, and seasonal high-water table estimations.

A wetland water budget was also developed for the proposed wetland creation and restoration to determine if sufficient water is available to establish or reestablish wetlands on the site. It was also used to inform design development including proposed grading and plant community composition. The establishment and re-establishment of wetlands on the site will be accomplished through directed grading, ditch plugging and stream restoration designed to maximize the retention of surface water, floodplain re-connection, and groundwater inputs.

Highlights from the Mattawoman Creek Wetland and Stream Mitigation project:
  • 80 acres of land were placed into conservation easement and removed from active row crop production and cattle pasture. The easement, which is held by GreenTrust Alliance, provides permanent protection for all 80 acres.
  • Over 64 acres of wetlands will be restored, created, enhanced or preserved, which will sequester approximately 75 tons of carbon per year.
  • 3,798 linear feet of perennial stream will be restored by re-establishing, historic floodplain access during more frequent storm events, stabilizing hydraulics and geomorphology, and adding aquatic habitat value.
  • Full integration of the wetland and stream restoration elements will occur exponentially, increasing anticipated functions and values in the post construction condition. Functions include: storm damage and flood attenuation, groundwater recharge and discharge, nutrient cycling and sequestration, local water quality improvement, and wildlife habitat enhancements.
  • This project will also create and enhance the forested wetland and stream habitat for the State-listed Threatened Selys’ Sundragon (Helocordulia selysii).
  • As part of the site design, over 28,500 native trees and shrubs will be planted.
  • The Mattawoman Creek Mitigation Site is located within a Tier 3 Biodiversity Conservation Network area. These areas are classified by the Department of Natural Resources as “highly significant for biodiversity conservation” and are priority conservation areas that support critical species and habitats.
  • The project will yield advanced mitigation values: 7.913 in wetland credits and 1,595 in stream credits. These credits are durable and will be available for JBA’s use in order to satisfy permitted impacts associated with planned capital improvement projects.

Over 6,000 acres (25%) of the Mattawoman Creek watershed has been protected by public ownership and various conservation and agricultural easements, which, in addition to the Mattawoman Creek Mitigation Site, help ensure that Mattawoman Creek forever remains a high-quality destination for outdoor recreation.

Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of tidal and freshwater wetland rehabilitation projects. To learn more about our wetland restoration, creation, and enhancement services, visit: http://bit.ly/PHwetland

Innovative and Effective Approach to Wetland Restoration

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 Middlesex County and is surrounded by industrial, commercial, and residential development. As such, the area suffered from wetland and stream channel degradation, habitat fragmentation, decreased biodiversity due to invasive species, and ecological impairment. 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.

Recognizing the unique qualities and great potential for rehabilitating and enhancing ecological function on this county-owned parkland, 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. The team designed a restoration plan that converted 28.94 acres of degraded freshwater wetlands, 0.33 acres of disturbed uplands dominated by invasive species, and 1,018 linear feet of degraded or channelized streams into a species-rich and highly functional headwater wetland complex.

BEFORE
View of stream restoration area upon commencement of excavation activities. View of containerized plant material staged prior to installation.

 

We used an innovative approach to restore the hydraulic connection of the stream channel with its floodplain in order to support wetland enhancement. Additionally, to further enhance wetlands with hydrologic uplift, the team incorporated microtopography techniques, which creates a variable surface that increases groundwater infiltration and niches that support multiple habitat communities. This resulted in a spectrum of wetland and stream habitats, including the establishment of a functional system of floodplain forest, scrub shrub, emergent wetlands and open water. Biodiversity was also increased through invasive species management, which opened the door for establishing key native flora such as red maple, pin oak, swamp white oak, and swamp rose. The restored headwater wetland system also provides stormwater quality management, floodplain storage, enhanced groundwater recharge onsite, and surface water flows to Woodbridge Creek.

Completed in 2017, the integrated complex of various wetland and upland communities continues to provide high quality habitat for a wide variety of wildlife species including the state-threatened Black-crowned Night heron and Red-headed Woodpecker. The work done at the site significantly enhanced ecological function, providing high-quality habitat on indefinitely-preserved public lands that offer countless benefits to both wildlife and the community.

AFTER
Post-restoration in 2018, looking Northeast. View of wetland enhancement approximately 2 months after completion of seeding and planting activities.

 

Public and private partnerships were and continue to be critical to the success of this project. The diverse partnership includes Middlesex County Office of Parks and Recreation, Woodbridge Township, Woodbridge River Watch, New Jersey Freshwater Wetlands Mitigation Council, GreenTrust Alliance, GreenVest, and Princeton Hydro. The partners joined together as stakeholders to identify long term restoration and stewardship goals for Pin Oak Forest Preserve, and nearly four years later, the partners all remain involved in various aspects of managing the property and this project itself, ranging from fiscal oversight by New Jersey Freshwater Wetland Mitigation Council and GreenTrust Alliance, to permit and landowner access coordination performed by Woodbridge Township and Middlesex County, or the ongoing stewardship, maintenance, and monitoring of the project and the larger park, being conducted by being conducted by GreenTrust Alliance, GreenVest, and NJ Department of Environmental Protection.

This project was funded through the New Jersey Freshwater Wetland In-Lieu Fee program. In 2014, GreenTrust Alliance, GreenVest, and Princeton Hydro secured $3.8 million dollars of funding on behalf of the Middlesex County Parks Department to restore three wetland sites, which included Pin Oak Forest.

The Pin Oak Forest project is a great model for showcasing a successful approach to the enhancement of public lands through a dynamic multidisciplinary, multi-stakeholder partnership. And, because of proper planning and design, it has become a thriving wildlife oasis tucked in the middle of a densely-populated suburban landscape.

Princeton Hydro specializes in the planning, design, permitting, implementing, and maintenance of wetland rehabilitation projects. To learn more about our wetland restoration, creation, and enhancement services, visit: bit.ly/PHwetland

Wild & Scenic Film Festival is Coming to Hackettstown

To celebrate the 50th Anniversary of the Wild and Scenic Rivers Act, the Musconetcong Watershed Association (MWA) is hosting the “Wild & Scenic Film Festival On Tour”. The festival is free and open to the public, but seating is limited so, registration is required. The festival will be held on Sunday, September 9th from 10 am to 2 pm at Centenary University in Hackettstown, NJ.

To bring communities together around local and global environmental issues, The “Wild & Scenic Film Festival” goes “on-tour” partnering with nonprofit organizations and local groups to screen films year-round with hopes of inspiring individuals to take environmental action. The tour stops in 170 communities around the globe, features over 150 award-winning films, and welcomes over 100 guest speakers, celebrities, and activists who bring a human face to the environmental movement.

Credit: NPS.gov

The Hackettstown, NJ tour event will feature 11 short films including River Connections, which celebrates the 50th anniversary of the Federal Wild and Scenic Rivers Act, under which the Musconetcong River is protected. The film explores the importance of free-flowing rivers and highlights the recent Hughesville Dam removal project. An interactive panel event will follow the film screening and feature experts including MWA Executive Director Alan Hunt, Ph.D. and Princeton Hydro President Geoffrey Goll, P.E., who were both interviewed in the film.

“Our multidisciplinary approach to dam removal using ecology and engineering, paired with a dynamic stakeholder partnership, led to a successful river restoration, where native fish populations returned within a year,” said Princeton Hydro’s President Geoffrey Goll, P.E. “We are grateful for MWA’s hard work in organizing this film festival so we can continue to share our dam removal success stories and the importance of the Wild and Scenic Rivers Act.”

Princeton Hydro, a proud sponsor of the “Wild & Scenic Film Festival On Tour,” has worked with MWA to design five dam removals on the Musconetcong River, including the Hughesville Dam. As noted in the River Connections film, the Hughesville Dam was a major milestone in restoring migratory fish passage along the Musconetcong. Only a year after the completion of the dam removal, American shad were documented as having returned to the “Musky” for the first time in 250 years.

The tour leads up to the annual 5-day film festival, which will be held January 17-21, 2019 in Nevada City and Grass Valley, California. Sponsored by National Park Service, the Wild & Scenic Film Festival honors the Wild and Scenic Rivers Act, landmark legislation passed by Congress in October 1968 that safeguards the free-flowing character of rivers by precluding them from being dammed, while allowing the public to enjoy them. It encourages river management and promotes public participation in protecting streams.

EVENT DETAILS:

Date:         Sunday, September 9th

Time:         Doors open at 10 am and shows start at 11 am

Location:  Centenary University, Sitnik Theatre,
                  400 Jefferson St, Hackettstown, NJ 07840

Tickets:     FREE! Please register in advance:
                   https://goo.gl/NrwcgE

 

Interested to learn more about River Connections?
Check out our blog celebrating the release of the film: 

Restoring and Revitalizing Freshwater Mussels

Freshwater mussels are among the oldest living and second most diverse organisms on Earth with over 1,000 recognized species. Here in the eastern part of the U.S., we have more species of freshwater mussels than anywhere in the world. Unfortunately, freshwater mussels are one of the most rapidly declining animal groups in North America. Out of the 300 species and subspecies found on the continent, 70 (23%) have been federally listed as “Threatened” or “Endangered” under the Endangered Species Act. And, in the last century, over 30 species have become permanently extinct. So, why are populations declining so fast?

Freshwater mussels are filter feeders and process large volumes of the water they live in to obtain food. This means of survival also makes them highly susceptible to industrial and agricultural water pollution.  Because they are constantly filtering water, the contaminants and pathogens that are present are absorbed into the mussel’s tissues. As such, mussels are good indicators of water quality and can greatly contribute to improving water quality by filtering algae, bacteria and organic matter from the water column.

Not only do freshwater mussels rely on water quality, they are dependent on fish and other aquatic organisms for reproductive success. In order for a freshwater mussel to complete the reproduction process, it must “infect” a host fish with its larvae. The method depends on the specie of mussel. Some species lure fish using highly modified and evolved appendages that mimic prey. When a fish goes into investigate the lures, the female mussel releases fertilized eggs that attach to the fish, becoming temporarily parasitic. Once the host fish is infected, it can transfer the mussel larvae upstream and into new areas of the river.

Both habitat loss from dam construction and the introduction of pesticides into the water supply has contributed to the decline of freshwater mussels. With approximately 300 mussel species in the U.S. alone, a critical component of restoring and revitalizing mussel populations is truly understanding their biology, which begins with the ability to properly differentiate each species and properly identify and catalog them. Princeton Hydro’s Senior Scientist Evan Kwityn, CLP and Aquatic Ecologist Jesse Smith recently completed the U.S. Fish and Wildlife Service‘s Fresh Water Mussel Identification Training at the National Conservation Training Center in West Virginia.

Through hands-on laboratory training, Evan and Jesse developed their freshwater mussel identification skills and their knowledge of freshwater mussel species biology. Course participants were tasked with mastering approximately 100 of the most common freshwater mussel species in the United States. They also learned about proper freshwater mussel collection labeling, the internal and external anatomy and meristics of a freshwater mussel, and distributional maps as an aid to freshwater mussel identification.

In a recently published press release, Tierra Curry, a senior scientist with the Center for Biological Diversity was quoted as saying, “The health of freshwater mussels directly reflects river health, so protecting the places where these mussels live will help all of us who rely on clean water. This is especially important now, when we see growing threats to clean water from climate change, agriculture and other sources.”

Princeton Hydro is committed to protecting water quality, restoring habitats, and managing natural resources. Read about some of our recent projects and contact us to discuss how we can help you.

To learn more about freshwater mussels, check out this video from U.S. Fish and Wildlife Service:

UPDATE: The Columbia Dam Is Coming Down

It’s happening! The Columbia Dam on the Paulins Kill in Northern New Jersey is finally coming down thanks to a successful collaboration between The Nature Conservancy, American Rivers, U.S. Fish and Wildlife Service, NJDEP Division of Fish and Wildlife Service, and Princeton Hydro. The first cut on the main dam wall was made just two weeks ago, and the water has started flowing downstream as the concrete is slowly being removed by the contractors RiverLogic Solutions and SumCo Eco-Contracting.

“In New Jersey, successful dam removal projects are often the result of partnerships between nonprofit organizations, federal and state agencies, consultants, and others working together toward the common goal of river restoration,” exclaimed Dr. Laura Craig, Director of River Restoration, American Rivers. “The first day of dam demolition is always a joyous occasion for project partners, but I was especially happy to see the river flowing through the breached Columbia Dam for the first time after working so intensely on this project for the last few years.”

Princeton Hydro has been involved with the engineering and restoration design from the beginning, so we’re very excited to report on this major update.  Our team of engineers and ecologists studied the feasibility of removal as requested by American Rivers in partnership with the New Jersey chapter of The Nature Conservancy.  We investigated, designed, and prepared the necessary permits for the removal of this dam. And, now we’ve been subsequently been hired to provide construction administration services during the removal process, which means we get to see the dam come down firsthand, piece by piece!

“It is truly amazing and exciting to finally see the main and remnant dams come down, as I have been involved in this restoration effort since the feasibility stage,” said Kelly Klein, Senior Project Manager, Princeton Hydro. “I am so honored to be part of this dynamic team and to collaborate with our project partners during every stage of this dam removal.”

Geoff Goll, Princeton Hydro and Beth Styler Barry, The Nature Conservancy on site August 3, 2018. Photo credit: Laura Craig, American Rivers

“On Friday, August 3rd 2018, we began demolition of the 300 foot-long, 18 foot-high Columbia Dam. The Paulins Kill will run freely to meet the Delaware River for the first time in 109 years,” said New Jersey Nature Conservancy’s Beth Styler Barry. “The benefits of reconnecting these two freshwater ecosystems will be immediate and impact creatures that live in and near the stream, as well as people who come out to paddle, fish or enjoy the wildlife. Dam Removal projects are exciting, ecologically important and also a challenge, this project is a good example of partners coming together to get a great restoration project done.”

Because this is a big deal, we want to keep *YOU* updated on what’s happening from the field. Moving forward, we’ll post weekly blogs with scenes from the site.  Here’s a snapshot of what’s been happening over the last last two weeks:

August 1, 2018. Photo credit: Casey Schrading, Princeton Hydro

In order to make the first saw cut into the dam, Princeton Hydro and RiverLogic Solutions first identified the locations of the drill holes. These drill holes are used to feed the diamond wire through the dam for saw cutting.

August 1, 2018. Photo credit: Casey Schrading, Princeton Hydro

The crew placed the saw cutter machine on the staging area on top of the apron and prepared for the cut.

August 3, 2018. Photo credit: Princeton Hydro

In order to create a notch in the dam, the crew supplemented the saw cutting with hammering.

August 3, 2018. Photo Credit: The Nature Conservancy, Columbia Dam Volunteer Drone Team

August 3, 2018. Photo credit: Erik Sildorff, Delaware Riverkeeper Network

August 7, 2018. Photo credit: Casey Schrading, Princeton Hydro

Since the high water level was now higher than the bottom of the breach, water is able to flow in and over the notched section.

August 14, 2018. Photo credit: RiverLogic Solutions

Because of high flows of water from recent storm events, the dam breach is being widened to allow for larger flows of water to move downstream during high flow events. 

Additionally, a few weeks ago we reported on the lowering of the water levels and removal of the remnant dam downstream (below).

PHOTOS: Columbia Dam Removal

Since then, the remnant dam has been completed removed and the area has been stabilized.

July 23, 2018. Photo credit: Casey Schrading, Princeton Hydro

Now, the water can freely flow through this section of the Paulins Kill.

And, in case you missed it, we celebrated the commencement of the Columbia Dam removal with NJDEP’s Commissioner Catherine McCabe and our project partners. Full story below:

Celebrating the Columbia Dam Removal

Princeton Hydro has designed, permitted, and overseen the reconstruction, repair, and removal of a dozens of small and large dams in the Northeast. To learn more about our fish passage and dam removal engineering services, visitbit.ly/DamBarrier.

Lithuania Hosts First-ever Dam Removal Workshop Feat. Princeton Hydro Expert

Lithuania Hosts its First-Ever
Dam Removal Workshop

Princeton Hydro’s Laura Wildman Invited to Present

History was recently made in Lithuania with the occurrence of the first-ever dam removal workshop held in the country. Experts throughout the world convened at the Ministry of Environment in Vilnius, the capital of Lithuania, to lead discussions on a variety of topics related to dam removal and river rehabilitation.  They covered the current state of affairs regarding Lithuanian dams and showcased the Dam Removal Europe (DRE) initiative, a new effort aimed at restoring rivers in Europe.

The workshop was the brainchild of Lithuanian environmental activist Karolina Gurjazkaitė. She read about the DRE campaign and was so inspired by the initiative, she contacted DRE representatives about organizing the workshop. Her goals in organizing the first-ever dam removal workshop in Lithuania were to build awareness around the importance of river restoration, call attention to the many outdated, unmaintained, and unnecessary dams throughout Lithuania, and ultimately inspire positive changes in the way of dam removals and river rehabilitation.

“I am very excited, not only about the workshop, but also about the ‘side effects’…already created,” said Karolina. “People are gaining hopes and enthusiasm… This workshop may have really powerful outcomes!”

Karolina gathered a diverse group of workshop attendees, comprised of government officials (including the Vice-Minister of Environment of Lithuania), university professors (primarily specializing in dam safety and hydropower development), local environmental advocates and NGO volunteers, researchers, and students.

Presenters during the workshop included scientists, engineers, communication experts, planners, activists, and Princeton Hydro’s New England Regional Office Director and Fisheries Engineer Laura Wildman, P.E.

Presentations covered a wide variety of topics, including:

  • Policy and current situation in Europe: Pao Fernández Garrido of World Fish Migration Foundation, Spain presented on DRE findings related to policy and the current dam removal situation in Europe.

  • Research: Rachel Bowes from Karlstad University, Sweden spoke about current state of affairs with Swedish dam removal efforts and the research they are currently carrying out.

  • Book presentation: Herman Wanningen of World Fish Migration Foundation, Netherlands presented the new book, From Sea to Source 2.0, which is focused on tackling the challenges of restoring fish migration in rivers around the world and is available for free download.

  • Technical issues: Laura Wildman, PE, who has over 20 years of experience on dam removal, presented on the most important technical aspects when carrying out a barrier demolition.

On day two of the workshop, participants were invited to take part in field visits to five dam sites. Each of the five dams all presented their own unique challenges in terms of the ability to remove them. The site visits provided a deeper look into the challenges that will need to be addressed when forging ahead with a Lithuanian river restoration initiative.

The workshop proved to be instrumental in identifying key challenges and next steps in building a successful country-wide river rehabilitation initiative. One of the key takeaways from the workshop is the need for a more robust understanding of Lithuanian-specific rules and regulations that classify a dam removal project as either viable or not viable.

“Not only has there never been a dam removal workshop held in Lithuania, to date, a dam removal has never been completed in Lithuania, at least none that have been documented and none for environmental restoration reasons,” said Laura. “It’s clear that we still have a lot to explore and discover, but I am so thrilled to have been a part of this workshop. It was a very positive first step in the right direction, and I’m looking forward to watching and helping this initiative flourish.”

To learn more about Princeton Hydro’s dam removal and river restoration initiatives, go here.