American Shad Discovered Just Miles Upstream of Former Columbia Dam

Struggling fish species returns to spawning grounds for the first time in over a century, just months after dam removal completed

For the first time in over a century, American Shad (Alosa sapidissima) have been discovered upstream from the former Columbia Dam site on the 42-mile long Paulins Kill river, an important tributary to the Delaware River in northwestern New Jersey. Princeton Hydro’s Senior Water Resources Engineer and avid fisherman, Dr. Clay Emerson, PE, CFM, caught an American Shad in the Paulins Kill miles above the previous dam site this past weekend.

A successful collaboration between The Nature Conservancy, American Rivers, Princeton Hydro, U.S. Fish and Wildlife Service, and NJDEP Division of Fish and Wildlife Service, resulted in the removal of the out-of-commission hydroelectric Columbia Dam just months ago. Prior to this removal, American Shad and other migratory fish could not make it past the large dam structure to swim upstream to their important breeding grounds.

“I was thrilled to feel the familiar hit and see the flash of an American Shad as I reeled the fish to shore. Being an avid shad fisherman and enthusiast, I knew the significance of seeing this beautiful fish back in a place where it’s always belonged,” said Clay. “We are thrilled to witness the American Shad return upstream so quickly after the century-old Columbia dam was removed. It’s a testament to the nearly instant benefits that dam removal has on the riverine ecosystem.”

The American shad’s return is an excellent sign of the overall ecological health and diversity of the river. Historically, dams, overfishing, and pollution have caused population decline in many of the major eastern U.S. rivers. American Shad, deemed the “Mid-Atlantic salmon,” are anadromous, which means they spend much of their lives in the ocean but return to rivers and their tributaries to spawn. This long distance swimmer makes it one of the Earth’s great travelers. After spawning upstream in rivers of the East Coast, American Shad migrate to their primary habitat in the Atlantic Ocean up in the Gulf of Maine. Unlike the salmon of the Pacific Ocean, American Shad may return to their spawning grounds multiple times over their lifetime. The species is a key prey species for many large fish and cetaceans like dolphins and whales in the Atlantic Ocean.

“The best indicator of river water quality improving in the Paulins Kill is the appearance of shad miles upstream from the Columbia Dam,” said Dr. Barbara Brummer, New Jersey State Director of The Nature Conservancy. “Today, we celebrate proof that with the 100-year dam impediment removed, they are once again successfully swimming up the river. I could not be happier! This is what teamwork and passion for nature can achieve. It is a great day for conservation in New Jersey, with many more great days for shad in the Paulins Kill to come.”

Princeton Hydro was contracted to investigate, design, and apply for permits for the removal of this dam as requested by American Rivers in partnership with the New Jersey chapter of The Nature Conservancy. The firm investigated, designed, and prepared the necessary permits for the dam removal. The team of engineers and ecologists studied the feasibility of removal by collecting sediment samples, performing bioassay tests, and conducting a hydraulic analysis of upstream and downstream conditions.

A view of the Columbia Dam at the beginning of the removal process.

“We are proud to be a part of this collaborative project, which has had an immediate and positive impact to the ecosystem of the Delaware River Watershed and its fishery resources,” said Princeton Hydro’s President Geoffrey Goll, PE. “Re-discovering this Delaware River diadromous icon upstream of the former dam is a very promising sign that the river will once again return to a major migration route and nursery for American Shad. This is why we do what we do!”

A view of the former Columbia Dam towards the end of the dam removal process.

This Columbia Dam Removal project could not have been possible without the hard work and dedication of the following partner organizations: The Nature Conservancy of New Jersey, American Rivers, Princeton Hydro, U.S. Fish and Wildlife Service, RiverLogic Solutions, NJDEP Division of Fish and Wildlife Service, and SumCo EcoContracting.

Anglers are reminded, according to New Jersey fishing regulations, except for the Delaware River mainstem it is illegal to fish for shad in any fresh waters of New Jersey.

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.

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.

PHOTOS: Columbia Dam Removal

VIDEO: “Columbia Lake Dam when the water level was 18 inches to 2 feet lower”
Video courtesy of Matt Hencheck

In Northwest New Jersey on the Paulins Kill, an important tributary to the Delaware River, the century-old hydroelectric Columbia Dam is actively being removed. Princeton Hydro was contracted by American Rivers to investigate, design, and apply for permits for the removal of this dam for the New Jersey chapter of The Nature Conservancy. Our team of engineers and ecologists studied the feasibility of removal by collecting sediment samples, performing bioassay tests, and conducting a hydraulic analysis of upstream and downstream conditions. We’re excited to report that the Columbia Dam removal has officially commenced!

The New Jersey Department of Environmental Protection started draining water from Columbia Lake a few weeks ago, which was the first step in removing the dam. Princeton Hydro has subsequently been contracted by The Nature Conservancy to provide construction administration services.  Photos below show the water at lowered levels at the impoundments.

“Dewatering Impoundment” Photo by Princeton Hydro

“An aerial drone snapshot when water levels were down about 5 feet at the upper impoundment” Photo courtesy of the New Jersey Chapter of The Nature Conservancy

Last week, the first hammer hit the wall of a downstream dam remnant, officially starting the removal process.

“The first hammer”  Photo courtesy of Dale Bentz, RiverLogic Solutions

The dam removal process will last a few weeks, as the contractor actively knocks down the thick concrete wall.

“Pressure and time”  Photo courtesy of Dale Bentz, RiverLogic Solutions

“Halfway there”  Photo courtesy of Dale Bentz, RiverLogic Solutions

Once the dam is removed, there is a high probability that populations of American Shad and River Herring will be restored. It may also enhance American Eel migration. As a coldwater fishery, this reach also has significant potential for trout species, as well as Smallmouth Bass.

(Top) Before: Photo of the Columbia Dam before construction. (Bottom) After: Princeton Hydro’s rendering of what the river will look like once the dam is removed.

“It is very exciting to be a part of such a monumental effort for the restoration of the Paulins Kill. This river, once a major migration route for diadromous fish like American Shad, will once again be a nursery for this Delaware River icon,” said Geoffrey Goll, PE, President and co-founder of Princeton Hydro. “The removal of these dams will also restore the functions and values of a riparian corridor and floodplain, eliminate costs to the taxpayer for the maintenance of a dam and lake, and provide additional riverine recreational opportunities. I expect to see the same resilience and positive impact to the Delaware River as the recent barrier removals on another major NJ tributary, the Musconetcong River. It is a win-win for NJ, and with The Nature Conservancy at the helm and expert guidance from American Rivers, it has been an experience of a career.”

This project could not have been possible without the hard work and dedication of the following partner organizations: The Nature Conservancy of New Jersey, American Rivers, U.S. Fish and Wildlife Service, RiverLogic Solutions, NJDEP Division of Fish and Wildlife Service, and SumCo EcoContracting.

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.


This video from 2016 features the Nature Conservancy’s New Jersey State Director Barbara Brummer, Ph.D. speaking on the Columbia Dam removal. Video credit: NJ Herald.

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.