Dam Removal on the Moosup River

Moosup River

The Moosup River is a beautiful 30-mile-long, trout river flowing through Connecticut and Rhode Island, eventually emptying into the Quinebaug River.

Several dams, most originally built in the 1800s or early 1900s, impeded the river’s natural flow, impaired habitat, fragmented the river system, and prevented fish from swimming upstream to their native spawning grounds.

In 2013, American Rivers, CTDEEP Fisheries, and Natural Resources Conservation Service began collaborating on the removal of multiple dams and remnant dams as part of a larger project to restore connectivity to the Moosup River in the Town of Plainfield. Princeton Hydro and RiverLogic Solutions were contracted to provide design-build and permitting services.

As part of this larger multi-year effort, five dams are planned for removal from the Moosup River. The most downstream barrier, the Hale Factory Dam was removed in 2014. The remnants of the toppled Griswold Rubber Dam were removed in 2015. In 2017, the removal of Brunswick Mill Dam #1 was completed. And, two more dams, downstream of New Brunswick Mill Dam #1, are currently under consideration for removal. When fully completed, the Moosup River Dam Removal Project will reconnect fish habitats along 6.9 miles of the Moosup River.

 

Hale Factory Dam

The Hale Factory Dam was constructed of a boulder core capped in a one-foot-thick concrete layer. The dam was partially breached as the concrete cap had deteriorated severely over the years, allowing flow to pass between boulders and allowing the normal pool elevation to drop substantially from its former design height.

The resource delineation conducted on site identified a vernal pool with an 18 inch culvert outlet that discharged 90 feet upstream of the dam. To preserve this ecological resource on the site, the vernal pool was not disturbed during the dam removal.

Princeton Hydro provided a field assessment, sediment characterization and analysis, final design and permit application package for the full removal of the Hale Factory Dam. Full removal of the dam entailed demolition and removal of the concrete, and re-use of the natural cobbles and boulders from the dam to create in-stream habitat features. Once completed, the river and its boulders appeared as if placed by nature itself, with the former dam’s presence indicated only by the age-old lichen covered field stone walls leading up to the banks.

 

Griswold Rubber Dam

The Griswold Rubber Dam was in a gravel-cobble reach of the river approximately 80 feet wide in the Village of Moosup and was adjacent to the 1992 expansion of the Griswold Rubber factory.  At one time, the dam stood approximately 10 feet high and 150 feet long. The dam was constructed of a large segmented concrete slab that had since toppled over and was lying nearly flat on the river bed in multiple sections. The dam structure, having failed, served no useful purpose. Despite being toppled, the dam still presented a deterrent to the effective movement of aquatic organisms at normal to low flows and was therefore worthy of complete removal to restore river connectivity.

Princeton Hydro conducted an initial field investigation with RiverLogic Solutions to gain insights regarding the construction approach. Princeton Hydro then followed-up with a more detailed assessment of river bed sediment, geomorphic conditions, the likely riverine response, construction access, and other design related issues that were incorporated into design plans and permit applications. The restoration design Princeton Hydro developed aimed to remove the partial barrier to fish passage with as little disturbance to surrounding infrastructure and resources as possible.

 

Brunswick Mill Dam #1

This dilapidated timber crib dam stood approximately 4-feet high and spanned the channel at approximately 130 feet. The timbers ranged from 1.5 to 2.5 feet in diameter and over 20 feet in length; 50 were integrated into the dam. The timber crib was filled with gravel and other debris, and the gravel substrate extended 50 feet upstream. The original dam was significantly higher, but the timber crib spillway deteriorated and gradually collapsed over time and only a portion of the structure remained.

For this project, Princeton Hydro completed sediment investigation, sampling and analysis; hydrologic and hydraulic analysis; and provided design and engineering for full removal of the dam. Princeton Hydro contracted with an archeologist / industrial historian, and together closely observed the dam deconstruction to observe and record how the timber crib had been assembled. Multiple types of iron pins and wooden pegs revealed how the dam had been repaired over the years – findings, old maps, and photos were incorporated into a historical report filed with the state historic preservation office. Princeton Hydro coordinated to have the old timbers salvaged for eventual re-use. Removing the Brunswick Mill Dam #1 was a continuation of the large scale Moosup River restoration effort and paved the way for the potential removal of two more dams downstream in the coming years.

“When a dam is breached and taken out, the tangible results are very quickly noticeable,” said Paul Woodworth, Princeton Hydro Fluvial Geomorphologist. “The return of migratory fish is a very strong indicator of the ecological benefits of dam removal – sometimes after a removal you can see fish immediately swimming upstream. Removing dams also improves safety in nearby communities, reestablishes the natural flow of sediment, improves water quality, provides new recreation opportunities, and restores habitats for fish and wildlife.”

Click here to read more about Princeton Hydro’s engineering services for the restoration and removal of dams.

New Book Aims to Protect and Restore Fish Migrations

Rivers are a critical natural resource and an essential element for the health and survival of billions of people and countless species. Flourishing populations of migratory fish are an important indicator of a healthy, coastally connected river and a robust aquatic ecosystem as a whole. Migratory fish help to maintain a balanced food web, support productive river systems, and provide income for people around the world.

Yet many migratory fish species are severely threatened primarily due to man-made obstacles like dams and weirs, which disrupt the natural flow of rivers and prevent fish migration. When fish can’t reach their habitat, they can’t reproduce and maintain their populations.

Photo Credit: “From Sea to Source 2.0”

A new book, titled From Sea to Source 2.0, explores the challenges that lie behind restoration of fish migration in rivers around the world and provides a practical guide to promoting the protection and restoration of fish migration. The book is a unique collaboration of over 100 international fisheries professionals and supported by river managers, governments, research institutes and NGOs including World Wildlife Fund and The Nature Conservancy. Geared toward practitioners, but also a wonderful resource for the general public, the book is comprised of inspiring stories from nearly every continent on the planet. Click here to download it for free.

“Ultimately our ambition is to contribute in a positive way to making a better world and a positive difference for migratory fish, nature and humans on local and global levels by inspiring new initiatives for and with people all around the world,” as stated on www.fromseatosource.com. “Whether the challenge is simply to increase access to spawning habitats through connectivity improvements for salmon, or to maintain the livelihoods for hundreds of millions of people dependent upon fish and fisheries in the great rivers of Asia, Africa and South America, we hoped our book would help to achieve these goals.”

Princeton Hydro’s Dam Removal Expert Laura Wildman, P.E. and Fluvial Geomorphologist Paul Woodworth are proud contributors to the book, helping to write the dam removal chapter, creating a dam removal flow chart for the book, and providing multiple photos utilized in the book. Princeton Hydro is also listed as a contributing sponsor.

“We’re so proud to be part of this incredible project with so many partners globally,” said Wildman. “We envision that this book will provide a valuable resource and inspiration for those in countries and regions where the importance of restoring riverine connectivity is newly gaining momentum. We hope it will help emphasize the importance of finding balanced and environmentally informed solutions when proposing additional utilization of public trust resources such as rivers.”

Approximately 40% of all fish species in the world reside in freshwater ecosystems, contributing economic and ecological benefits and value. It’s critical that we support efforts that aim to protect migratory fish species, reconnect rivers, sustain fish passage, and preserve free-flowing rivers through removing unnecessary dams, reconnecting floodplains, managing our water use, and managing hydropower for sustainable rivers.

Education and awareness building are key first steps in protecting rivers. From Sea to Source 2.0 seeks to inform, educate and inspire those who want to know more about how to meet the challenges of restoring fish migration in rivers around the world.  The book is regarded as a crucial resource in the ongoing fight to protect and preserve the enormous value of our waterways.

Get your free copy here.

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, visit: bit.ly/DamBarrier.

Conservation Spotlight: Restoring Fish Passage on the Noroton River

For thousands of years, river herring swam from the Atlantic Ocean through the Long Island Sound and up the Noroton River to spawn each spring. Then, they returned to the ocean until the next spawning season.

Back in the 1920s, President Dwight D. Eisenhower’s administration began connecting the country through a massive interstate highway system. As part of the infrastructure plan, hundreds of thousands of culverts were built across the U.S. with the intention of moving water quickly and efficiently. While that goal was met, many migratory fish and other aquatic organisms could not overcome the culverts’ high-velocity flows, shallow water depths, and perched outlets. This infrastructure prevented them from reaching their native migratory destinations.

By the late 1950s, Interstate 95 cut through Connecticut’s coastal rivers, and culverts were installed to convey river flows. Alewives, American Shad, Blueback Herring, and other native fish species were unable to navigate the culverts. Their populations dwindled to the point where Connecticut, along with Rhode Island, Massachusetts, and North Carolina, instituted moratoriums on catching and keeping the valued forage fish.

Along the Noroton River, three parallel concrete culverts, each 300-feet long, 13-feet wide and 7-feet in height were installed, completely blocking upstream fish passage.  In order to restore important fish populations and revitalize the Noroton River, Save the Sound launched a project that reopened approximately seven miles of the river, allowing migratory fish populations to safely and easily travel through the culverts to reach their original spawning habitat upstream.

The project is a collaboration among Save the Sound, Darien Land Trust, Connecticut Department of Energy and Environmental Protection (CTDEEP), Connecticut Department of Transportation, Princeton Hydro, and other partners. For the project, Princeton Hydro lead design engineering and guided the construction of the following elements to restore upstream fish passage:

  • The installation of a concrete weir at the upstream end of the culvert to increase water depths in one culvert during low-flow periods;
  • The installation of concrete baffles to reduce flow velocities and create resting places for fish, and;
  • The installation of a naturalized, step-pool, rock ramp at the downstream end of the project to allow fish to ascend into the culvert gradually, overcoming the two-foot vertical drop present under existing conditions. The rock ramp consists of a grouted riverstone base with large grouted boulders arranged to make steps, with low-flow passage channels, between a series of pools approximately 1-foot deep that create resting places for upstream migrating fish.

Reopening river passage for migratory species will improve not only the health of the Noroton River itself, but will also benefit the overall ecosystem of Long Island Sound. Over the last decade, fish passage projects around the sound’s Connecticut and New York shores have dramatically increased freshwater spawning habitat for the foundational species whose return is restoring a more vibrant food web to the Long Island Sound.

Construction of the baffles and rock ramp were completed in time for the 2018 migratory season. Construction of the concrete weir is on temporary hold for low-flow conditions. On April 26, 2018, project partners gathered for a project celebration and the release of migratory fish by CTDEEP at an upstream location.

“It’s fascinating to feel the change in the flow patterns against your legs as you walk through the baffled culvert knowing that it will now facilitate fish passage through this restored reach,” said Princeton Hydro’s New England Regional Office Director and Water Resources and Fisheries Engineer Laura Wildman, P.E. “It is a very attractive and natural-looking fishway, and we’re proud to have created a design that fits so well into the surrounding landscape.”

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, visit: bit.ly/DamBarrier.

UPCOMING EVENTS: SPRING UPDATE FROM PRINCETON HYDRO

Throughout April and May, Princeton Hydro is participating in a variety of events focused on conserving, restoring, and protecting our precious water resources.

April 11: New Jersey Invasive Species Strike Team 10th Annual Conference

Presented by the Friends of Hopewell Valley Open Space, the 10th Annual New Jersey Invasive Species Strike Team Conference is considered the most comprehensive state-wide forum on invasive species. The conference brings participants together to collaborate and address new and emerging invasive species issues from a state-wide perspective, and includes an exhibitor hall, networking opportunities and a variety of presentations and panel discussions on topics ranging from “Rare Bird Conservation” to “Foraging for Invasive Species” to “Herbicide Application Techniques.”

Princeton Hydro, a proud sponsor of the conference, will be exhibiting. We hope to see you there!

View the full conference schedule.

 

April 14: Musconetcong River Watershed Cleanup

As part of the 26th Annual Musconetcong River Cleanup on April 14th from 9 AM – 12 PM, Princeton Hydro will be leading a volunteer team at the Warren Glen Dam site. Friends and family welcome to join us!

For details, visit the Musconetcong Watershed Association’s event page.

 

April 18: The New England Chapter of the American Public Works Association Spring Conference

The New England Chapter of the American Public Works Association (NEAPWA) serves professionals in all aspects of public works and supports the people, agencies, and organizations that plan, build, maintain, and improve communities.

This year’s NEAPWA Spring Conference is being held at the Pratt & Whitney Stadium in East Hartford, CT. The conference includes a tour of the stadium, an exhibitor hall, educational session, and technical workshops on topics, like “Water System Infrastructure Planning in Response to Drought Conditions,” “Leveraging GIS Technology with Municipal LED Street Lights,” and “Using Infiltration and Inflow to Work Smarter not Harder.”

View the full conference agenda.

 

April 26: Arbor Day Planting and Bird Walk at Exton Park

We’re celebrating Arbor Day on April 26th (one day early) with Friends of Exton Park. First, we’ll be on the lookout for spring migrants during a morning bird walk (8:30 AM – 10:30 AM). Then, we’ll show our Arbor Day spirit by planting a variety of native plants at Exton Park (11:00 AM). We hope you’ll join us!

Click here to RSVP.

 

 

May 4: New York State Federation of Lake Associations Annual Conference

The New York State Federation of Lake Associations will host its 35th Annual Conference at the Fort William Henry Conference Center in Lake George, NY.  This year’s conference, which is titled, “Protecting Our Lakes for 35 Years – Our Past, Present and Future,” will feature a diverse exhibitor hall, networking opportunities, a silent auction and a variety of educational sessions. Princeton Hydro is exhibiting and giving five presentations:

  • Nutrient Inactivation: A Pennsylvania Case Study
  • You Have Your Lake Data, Now What? Creating a Watershed Plan
  • One Watershed, Many Lakes: A Strategic Plan for the Kettle Lakes of Southern Onondaga and Northern Cortland Counties
  • Proactive Management of Harmful Algal Blooms
  • Hydrilla Control in Harveys Lake, PA

Read more.

New Video Celebrates 50th Anniversary of Wild & Scenic Rivers Act

Credit: NPS.gov

Communities across the nation are preparing to celebrate the 50th anniversary of the Wild and Scenic Rivers Act. This landmark legislation passed by Congress in October 1968 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.

As part of the celebration, the National Park Service released a new video highlighting a handful of ‘Wild and Scenic’ designated rivers in the Northeast – the Farmington, Sudbury, Assabet, Concord, and Musconetcong Rivers – along with the organizations and community volunteers who work together to protect and care for these rivers.

Princeton Hydro is proud to work with two of the river stewards featured in the video: Musconetcong Watershed Association (MWA) and Farmington River Watershed Association (FRWA).

The Musconetcong River:

Designated ‘Wild and Scenic’ in 2006, the Musconetcong River is a 45.7-mile-long tributary of the Delaware River in northwestern New Jersey.

Princeton Hydro has been working with MWA in the areas of river restoration, dam removal, and engineering consulting since 2003 when the efforts to remove the Gruendyke Mill Dam in Hackettstown, NJ began. To date, Princeton Hydro has worked with MWA to remove five dams on the Musconetcong River, the most recent being the Hughesville Dam.

As noted in the video, the removal of these dams, especially 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 returned to the “Musky” for the first time in 250 years.

“The direction the river is moving bodes well for its recovery,” said Princeton Hydro President Geoff Goll, P.E., who was interviewed in the 50th anniversary video. “This multidisciplinary approach using ecology and engineering, paired with a dynamic stakeholder partnership, lead to a successful river restoration, where native fish populations returned within a year. ”

The Farmington River:

The Upper Farmington River, designated as ‘Wild and Scenic’ in 1994, stretches 14-miles through Connecticut starting above Riverton through the New Hardford/Canton town line. The river is important for outdoor recreation and provides critical habitat for countless wildlife.

Credit: FWRA.orgBack in 2012, Princeton Hydro worked with the FRWA and its project partners to remove the Spoonville Dam. Built in 1899 on the site of a natural 25-foot drop in the riverbed, the dam was originally a hydropower facility. The hurricanes and flood of 1955 breached the dam, opening a 45-foot gap and scattering massive dam fragments in the riverbed downstream. The remnant of the main dam persisted for decades as a 128-foot long, 25-foot high obstacle in the channel. The river poured through the breach in a steep chute that stopped American shad from proceeding further upstream to spawn.

The project was completed, from initial site investigation through engineering assessment and final design, in just six months. The dam removal helped to restore historic fish migrations in the Farmington River (including the American shad) and increase recreation opportunities.

Wild & Scenic Rivers Act:

Credit: NPS.govAs of December 2014 (the last designation), the National ‘Wild and Scenic’ System protects 12,734 miles of 208 rivers in 40 states and the Commonwealth of Puerto Rico; this is a little more than one-quarter of 1% of the nation’s rivers. By comparison, more than 75,000 large dams across the country have modified at least 600,000 miles, or about 17%, of American rivers.

In honor of the 50th anniversary of the Act and in an effort to designate many more miles of river as ‘Wild and Scenic,’ four federal agencies and four nonprofit groups are coordinating nationwide events and outreach. Managing agencies are the Bureau of Land ManagementFish and Wildlife ServiceForest Service, and National Park Service, along with American RiversAmerican WhitewaterRiver Network and River Management Society. Go here for more info: www.wildandscenicrivers50.us.

Musconetcong Watershed Association Presents Princeton Hydro President with Prestigious “Friend of the River” Award

 

Musconetcong Watershed Association (MWA) held a dinner to celebrate its 25th anniversary as well as the 150th anniversary of the Asbury Grist Mill, which the MWA is working to restore. The evening included a cocktail hour, a buffet dinner, silent auction, remarks by the MWA President Tish Lascelle and Executive Director Alan Hunt, and a presentation of awards.

The MWA presented Princeton Hydro PresiPhoto by Tish Lascelle, President, Musconetcong Watershed Associationdent Geoff Goll, PE with the “Friend of the River” Award. This award, which has only been given seven times in MWA’s 25 years of service, recognizes individuals who have made a significant and sustainable difference in the Watershed and helped to advance its mission. Recipients of the Award have also demonstrated outstanding leadership through their volunteer efforts or partnerships with MWA.

Geoff was honored to receive the award alongside Paul Kenney of the National Park Service and Richard C. Cotton, a Managing Partner of the Hawk Pointe Golf Club and Asbury Farms Real Estate. Paul was assigned the Musconetcong River in late 2003 and was instrumental in obtaining the Musconetcong River’s Wild and Scenic Designation in 2006. He has continued to be an excellent resource of the National Park Service.  Richard is a founding member of the MWA’s Board of Trustee’s and continues to serve on the Board. He has dedicated his professional life to striking a balance between economic growth with environmental protection.

Geoff has been working with MWA in the areas of river restoration, dam removal, and engineering consulting since 2003, when the efforts to remove the Gruendyke Mill Dam in Hackettstown, NJ began. He has since worked with the Princeton Hydro team to remove five dams on the Musconetcong River, the most recent being the Hughesville Dam

MWA is an independent, non-profit organization dedicated to protecting and improving the quality of the Musconetcong River and its Watershed, including its natural and cultural resources. Members of the organization are part of a network of individuals, families and companies that care about the Musconetcong River and its watershed, and are dedicated to improving the watershed resources through public education and awareness programs, river water quality monitoring, promotion of sustainable land management practices and community involvement.

During the anniversary dinner, participants also got a sneak peek of a new video from the National Park Service that is set for public release in 2018. The video celebrates the upcoming 50th anniversary of the Federal Wild and Scenic Rivers Act, under which the Musconetcong River is protected, and explores the importance of free-flowing rivers and why Americans treasure them. Representing Princeton Hydro at the awards dinner were Vice President Mark Gallagher, his wife Jennifer, Geoff and his wife Amy, and Director of Engineering Services Mary Paist-Goldman, PE.

 

 

 

 

 

 

 

 

 

 

 

Princeton Hydro Dam Removal Work Featured at Brazilian Workshop

As Brazil is in the midst of a dam-building boom, scientists and engineers gathered at a workshop in Brazil to discuss, “Dam Removal & Optimizing Hydro Locations to Benefit Species Diversity in Brazil.”

Laura Wildman, P.E., Water Resources and Fisheries Engineer and Director of Princeton Hydro’s New England Regional Office, was invited to speak at the workshop. Her presentation focused on why we remove dams in the U.S. (the key drivers), how we analyze them for removal, and what we are learning through a wide diversity of completed case studies.

“It was fascinating to discuss a topic, such as the removal of dams, right as Brazil is focusing on building more hydro capacity,” said Laura. “Hopefully it is a sign that the hydro industry in Brazil, along with all the great Brazilian fisheries researchers, are quite forward thinking and are determined to maintain their country’s rich species diversity while also enhancing their energy options.”

The workshop, hosted by CEMIG and held at UFMG, involved many universities, including our workshop host Paulo Pompeu from UFLA, Dr. Paul Kemp from University of Southhampton, Dr. Jesse O’Hanley of Kent Business School, and many others.

The gathering inspired a lot of interesting dialogue around dam removal, optimizing locations for new hydro facilities, and how to best sustain connectivity and species diversity. Laura’s presentation entitled “Dam removal in the United States” along with the other conference presentations will be available on the CEMIG website soon or check back here on the Princeton Hydro blog for presentation links.

The Restoration of Bound Brook

To the delight of fish and environmentalists alike, an important step has been made in the removal of the aging spillway of Hunters Pond Dam in Scituate and Cohasset, Massachusetts. The spillway was notched to ensure a gradual release of water from the impoundment, letting Bound Brook flow free again after being dammed for centuries.

As the first barrier upstream from the Atlantic Ocean, the dam’s removal restores 5-miles of river spawning ground and habitat for alewife, blueback herring, American eel, rainbow smelt, sea lamprey and other important species. The removal of Hunters Pond Dam also reduces the threat of dam failure.

Princeton Hydro is proud to be working on this project with T Ford Company, U.S. Fish and Wildlife Service, and many other great partners. The project is funded by grants from the Massachusetts Department of Ecological Restoration and the NOAA.

The project also includes rebuilding a culvert, removing a concrete spillway, and replacing a water main. Stay tuned for more!

The Return of the American Shad to the Musconetcong River

PHOTO/New Jersey Division of Fish and Wildlife biologist Pat Hamilton holds a shad near the Warren Glen Dam

After a 250+ year absence, American shad have returned to the Musconetcong River in Hunterdon and Warren counties. This milestone in the ecological recovery of the river is the result of the removal of dams on the lower Musconetcong several years ago, followed by the removal of the Hughesville Dam in Warren County last year.

Removing the dams opened nearly six miles of the Musconetcong to migratory fish, such as American shad, that spend much of their lives in the ocean but return to rivers and their tributaries to spawn. The shad’s return is a good sign of the overall ecological health and diversity of the river.

Princeton Hydro was proud to partner with the Musconetcong Watershed Association and so many other incredible organizations who came together on the Hughesville Dam Removal project. To date, Princeton Hydro has investigated, designed and permitted five dam removals on the Musconetcong.

The next Musconetcong dam targeted for removal is the 32-foot high Warren Glen Dam, less than a mile farther upstream. It is the largest dam in the river; by comparison, the Hughesville Dam was 15-feet tall.

Princeton Hydro President Geoff Goll, P.E. published this commentary piece titled, “The Return of the American Shad to the Musconetcong River:”

Update (June 15, 2017)NJDEP issued press release on the finding of American shad on the Musky. Bob Shin, NJDEP Commissioner, stated, “[t]he return of shad, a benchmark species indicative of the overall ecological health and diversity of a waterway, is an exciting milestone…. This achievement is the direct result of an ongoing partnership among state and federal agencies, nonprofit groups, and dam owners – all committed to making this beautiful waterway free-flowing again.

On June 7, 2017, Princeton Hydro celebrated along with the Musconetcong Watershed Association (and an excellent story of the MWA, human history of the river, and the efforts to preserve the history and ecology can be found here) and other project partners, the discovery of American shad on the Musconetcong River in NJ, over 250 years after they were blocked from this major tributary of the Delaware River – On September 8, 2016, then Secretary of the Interior, Sally Jewell, held a press conference to celebrate the initial breach of the Hughesville Dam on the Musconetcong River (time lapse of removal is here). The press conference was held as the Department of the Interior via of the US Fish and Wildlife Service provided the funding to remove this obsolete structure through their Hurricane Sandy Recovery funding and the Natural Resource Damage Assessment and Restoration program. In addition to the Honorable Sally Jewell, NJDEP Commissioner Bob Martin, and US Army Corp of Engineers, Philadelphia District Commander Lt. Colonel Michael Bliss, were also on hand to speak about the importance of the Hughesville Dam removal and dam removal in general. To have such dignitaries at the highest levels of our Federal and State government speak at a project our firm designed was truly an honor and privilege. It was a great day to celebrate the next obsolete dam on the Musconetcong River to fall to the progress of river restoration. However, this would pale in comparison to the news we received on Wednesday, June 7, 2017, when the NJ Division of Fish and Wildlife confirmed the presence of the American shad (Alosa sapidissima) above the Hughesville Dam!

Ms. Patricia Hamilton, Fisheries Biologist of NJ Fish And Wildlife, reported that they “spotted small schools of American Shad (at most 6 at a time) and captured 4 several hundred yards downstream of the Warren Glen Dam”, five miles from the confluence of the Delaware River. This is the first documentation of American shad on this river in over 250 years! So, what is the big deal you may ask.

The American shad is the Mid-Atlantic and Southeastern United States’ salmon; it is actually a clupeid, a forage type fish closely related to herrings and sardines. Like herrings and sardines, they are a very oily fish, high in omega-3 fats, and low in contamination. It is also a fairly large clupeid, reaching three to eight pounds as adults. Like the salmon, American shad are anadromous, meaning they live the major part of their lives in the ocean and spawn up the coasts’ rivers. The American shad is not a spectacularly looking fish to say the least, and in fact, looks like a “generic” illustration of a fish, unlike the sleek and sexy salmon. It doesn’t even jump. However, this fish is a long distance and endurance swimmer, who’s migration from its hatching in rivers of the East Coast to its primary habitat in the Atlantic Ocean up in the Gulf of Maine, makes it one of the Earth’s great travelers. It can swim nearly 20,000 kilometers in its first five years of life and can dive to depths of up to 375 meters. And like all of its clupeid kindred, it is both a key prey species for many large fish and cetaceans in the Atlantic’s pelagic zone (open ocean) and an important commercial fish. But it is the existence of over-fishing, pollution and dams that had brought this species to its knees in many of the major eastern US rivers.

While the Delaware River shad and herring species have rebounded somewhat from low populations in the mid-1900s with the advent of the US Clean Water Act, they continue to struggle to regain their numbers, and in fact, there is now a moratorium on catching river herring in the Delaware River, and NJ has a moratorium on the harvesting of shad and herring on its tributaries to the Delaware River and Atlantic Ocean. As far as tributary access is concerned, the largest tributaries to the Delaware, the Schuylkill and Lehigh Rivers, are still blocked by dams to their mouths with very little efficiency of fish ladders provided; with their dams having very little success in gaining support for the removal of their blockages. So, any gains in additional spawning habitat for such anadromous species is viewed as a significant victory. The opening of the Musconetcong River to migrating fish will be a large contributor to the rebound of American shad, and other river herring species.

As one of the original 13 colonies, NJ was an integral partner in the start of the United States and early industrial revolution. It has been documented through our research during the dam removal regulatory permit application process on this waterway that the Musconetcong River has been dammed just about all the way to its confluence with the Delaware River since the mid-1700s, and likely much earlier. So, before there was anyone who understood the importance of unimpeded rivers for fish migration, this particular route was cut-off in its entirety, and then remained so for well over 250 years. So, it is understandable that there was no reason to assume that anadromous fish, such as shad, would resume the use of the river in a short period of time; however, there existed the right habitat for them, should they be afforded access…and the hope of the partners working on this river. There were doubters, to be sure, but “lo and behold”, we now know these mighty fish took advantage of an opening almost immediately.

Now, I am not stating that American shad immediately realized that the Hughesville Dam was gone and took a B-line from the Delaware River to the highest unimpeded location. First, other dams downstream of the Hughesville Dam had been removed over the past several years. These dams included the Finesville Dam (for an excellent video of the story of this dam removal, check out this video by the US Fish and Wildlife Service), removed in 2011 and the Reigelsville Dam remnants (there were two additional remnants found when the first foundation was removed) soon after the Finesville Dam was removed. So, it is likely that American Shad had started moving up the river to the base of the Hughesville Dam between 2011 and 2016. Still the response by American shad is nothing short of spectacular. For the over 250 years this species has not been able to use this river, at all, and now, within a span less than six years of dam removal activities, this fish is raring to comeback and, hopefully, spawn and increase their numbers.

And the efforts are not nearly complete for the Musconetcong River. The finding of the American shad five miles upstream from the Delaware River shows that this river can and, now, does support this fish. This generic looking fish, yet awesome product of evolution should only fuel the fire of continued restoration efforts, proof-positive that the labor and funds spent here, in this river, gets results. Such funds and labor (an staggering amount of time, blood, sweat, and tears) are required in order to get the river restoration work done. These projects have received the majority of their backing from the federal government, through grant programs, natural resource damage funds, and direct Congressional authorized funds. Without support from Washington, D.C.,, and Trenton, none of this work would be possible. And to get these funds, required work by the many team partners to prepare applications, meet with federal agencies, and educate the public through open and transparent meetings and communication. This was an impressive effort by the residents of this watershed, professionals who provided their expertise, and the state and federal employees who have dedicated their lives to this kind of work.

The Musconetcong River, with its recovering ecosystem, and its human and non-human inhabitants continue to amaze me in how we should all strive to strike balance between man and nature; and all this is being accomplished in the most densely populated state in the nation.

The finding of American shad gives me reason to cheer, and is why I do what I do. This is it, the return of a species that at one time we had no assurance would return, has returned. This is hope for us, after all.

Read more about Princeton Hydro’s river restoration and dam/barrier services on our website. Please contact us anytime if you have a project you’d like to discuss.

Princeton Hydro Projects Recap

In Case You Missed It:
A Recap of Projects Recently Completed by the
Princeton Hydro Aquatic & Engineering Departments

Members of our New England Regional Office team conducted a detailed survey at a culvert prioritized for replacement in the Town of Stony Point, New York. This structure was one of several identified as important to both habitat and flood risk during the development of Stony Point’s Road-Stream Crossing Management Plan. The Princeton Hydro team will use the collected data to develop a conceptual design and implementation strategy for a replacement structure using the Stream Simulation design method developed by the U.S. Forest Service.

Special thanks to Paul Woodworth, Fluvial Geomorphologist, and Sophie Breitbart, Staff Scientist, for their excellent work on this project!

The Truxor was put to work dredging a pond in Union Gap, New Jersey. The Truxor is an extremely versatile amphibious machine that can perform a variety of functions, including weed cutting and harvesting, mat algae and debris removal, silt pumping, channel excavation, oil spill clean-up, and much more!

We recently designed and installed a solar-powered aeration system in Hillsborough, New Jersey. Solar pond and lake aeration systems are cost-effective, eco-friendly, sustainable, and they eliminate the need to run direct-wired electrical lines to remote locations. Princeton Hydro designs, installs and maintains various aeration and sub-surface destratification systems for public drinking water purveyors, municipal and county parks, private and public golf courses, and large lake communities throughout the East Coast.

Here’s a look at a project in Elizabeth, New Jersey to clear the area of phragmites. Phragmites is an invasive weed that forms dense thickets of vegetation unsuitable for native fauna. It also outcompetes native vegetation and lowers local plant diversity. Previously, the entire site was filled with phragmites. Late last year, we utilized the Marsh Master to remove the invasive weed. Now that its almost Spring, we’re back at the site using the Marsh Master to mill and cultivate the ground in preparation for re-planting native plant species. A big shout out to our Aquatic Specialist John Eberly for his great work on this project!

In this photo, our intern and engineering student currently studying at Stevens Institute of Technology, Veronica Moditz, is gathering data on the Hughesville Dam removal. She’s using GPS to check the elevation of the constructed riffle on the beautiful Musconetcong River.

Members of the Princeton Hydro team worked in South New Jersey doing annual maintenance on nine stormwater infiltration basins that were also designed and constructed by Princeton Hydro. The maintenance work involves clearing vegetation from the basins to ensure the organic matter does not impede infiltration of the water as per the basins’ design. This project also involves the management of invasive plant species within the basins. Stormwater infiltration basins provide numerous benefits including preventing flooding and downstream erosion, improving water quality in adjacent waterbodies, reducing the volume of stormwater runoff, and increasing ground water recharge.

We recently completed a project in New Jersey for which we used our Truxor machine to dredge a stormwater retention basin. The basin had accumulated large amounts of sediment which were impeding the flow of water into the basin. We equipped the Truxor with its standard bucket attachment and a hydraulic dredge pump. The dredging operation was a success and now the basin is clear and functioning properly.

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