WINNER! #LakesAppreciation Month Contest Results

Princeton Hydro’s #LakesAppreciation Month contest is officially closed, and we’re excited to announce Holden Sparacino as the winner! Holden, a Graduate Research Assistant at University of Vermont, has won a one-year membership to the North American Lake Management Association (NALMS) and a $100 Amazon gift card.

The Lakes Appreciation Month contest encouraged people who enjoy lakes to participate in a “Secchi Dip-In,” which is an annual citizen science event created by NALMS in 1994 in order to involve lake-goers and associations across North America in monitoring water quality by using a Secchi disk to monitor the transparency or turbidity of their local waterway.

Thanks so much to everyone who participated in the contest and showed your appreciation for lakes!

Read more about the Secchi Dip-in Contest here:

CONTEST ALERT: Celebrate #LakesAppreciation Month and Win $100

 

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.

Celebrating the Columbia Dam Removal

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

On a bright, sunny day in Warren County, Princeton Hydro celebrated the Columbia Dam Removal Project with New Jersey Department of Environmental Protection (NJDEP) Commissioner Catherine McCabe, The New Jersey Nature Conservancy (event organizer), American Rivers, U.S. Fish and Wildlife Service (USFWS), NJDEP Division of Fish and Wildlife Service, RiverLogic Solutions, and SumCo Eco-Contracting.

Beth Styler-Barry, River Restoration Manager, New Jersey Nature Conservancy

Overlooking the soon-to-be removed, century-old, hydroelectric Columbia Dam, key stakeholders, including Princeton Hydro’s President Geoffrey Goll, P.E. and New Jersey Nature Conservancy’s Director Barbara Brummer, remarked on the success of the project, collaborative team efforts, and future benefits to the Paulins Kill habitat.

NJ Nature Conservancy’s River Restoration Manager, Beth Styler-Barry thanked project funders including NJDEP’s Office of Natural Resource Restoration, USFWS’s Fish Passage Program, National Fish and Wildlife Foundation’s Bring Back The Natives program, Natural Resources Conservation Service’s Regional Conservation Partnership Program, New Jersey Corporate Wetlands Restoration Partnership, Leavens Foundation, Tom’s of Maine, and Nature Conservancy members and donors.

“We made a commitment early-on to a 10-year monitoring and measurement plan. The removal of Columbia Dam is an opportunity to gain new knowledge and generate data that builds the case for this type of restoration. We’ll be looking at everything from mussels to temperature to geomorphological changes to increasing our targeted efficiencies. We’re also going to use images taken from repeated drone flyovers to look closely at changes in topography,” said Styler-Barry.

NJDEP Commissioner Catherine McCabe with NJ Division of Fish & Wildlife and NJDEP officials.

NJDEP Commissioner Catherine McCabe added, “The Columbia Dam is ranked in the top 5% of the nearly 14,000 dams that were assessed for priority. It will give us one of the most bangs for our buck in terms of fish and native species that we’ll be able to bring back up here.” She added, “This is exactly what Natural Resources Damages funds should be used for, and we are thrilled to see it come to fruition.”

Geoffrey Goll, P.E., President, Princeton Hydro

Back in the day, this dam structure was a marvel of engineering. Because concrete was very expensive during the time of construction, a patented, innovative “ransom hollow” design was used, which means it has a hollow center with series of doorways underneath the dam, explained Geoffrey Goll, P.E., President of Princeton Hydro. However, sustainability and climate change are very important issues today and must be taken into consideration for the life-cycle of a dam.

“Removal is a logical step in the history of this dam. Dam removals are the most impactful restorations. They provide the most ecological uplift and improvement for rivers,” Goll stated.

For Princeton Hydro, this project involved every discipline we have in the firm: civil engineering, fishery biology, wetland science, hydraulics, geotechnical engineering, and regulatory work. We were contracted by American Rivers to investigate, design, and permit for the removal of this dam for the New Jersey Nature Conservancy. Our team of engineers and ecologists studied the feasibility of removal by collecting sediment samples, performed bioassay tests, and conducted a hydraulic analysis of upstream and downstream conditions. Currently, we are providing construction administration services during the removal process. This project is a great example of our ability to complete multi-disciplinary projects in-house.

Project partners ready for the first hammer with the celebratory dynamite and sledge hammers.

At the end of the press conference, project partners celebrated the anticipation of the “first hammer” in the near future with an imitation dynamite siren and plastic sledge hammers. It was truly a keystone moment for everyone involved in this project.

The remnant dam downstream has already been removed and the main dam is due to be removed very soon. Check out our previous story with a series of photos documenting this first-step in the overall dam removal process: bit.ly/ColumbiaDamRemoval. Stay tuned for photos during the main dam removal process too.

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.

Conservation Spotlight: Dunes at Shoal Harbor Shoreline Protection

Hurricane Sandy was the largest storm to ever originate in the Atlantic ocean. It badly damaged several countries in the Caribbean, caused over $50 billion in damages along the Eastern Seaboard, and left dozens dead. While hurricanes are a natural part of our climate system, research shows that intense hurricane activity has been on the rise in the North Atlantic since the 1970s. This trend is likely to be exacerbated by sea level rise and growing populations along coastlines. Natural coastal habitats — like wetlands and dunes — have proven to shield people from storms and sea-level rise, and have protected coastal communities from hundreds of millions of dollars in damage.

The Dunes at Shoal Harbor, a residential community in Monmouth County, New Jersey, is situated adjacent to both the Raritan Bay and the New York City Ferry channel. The site, previously utilized for industrial purposes, consisted of a partially demolished docking/berthing facility. A significantly undersized 6” diameter, 8-foot long stone revetment was also constructed on the property.

During Hurricane Sandy, the revetment failed and the community was subjected to direct wave attack and flooding. Homes were damaged, beach access was impaired, and the existing site-wide stormwater management basin and outfall was completely destroyed.

Princeton Hydro performed a wave attack analysis commensurate with a category three hurricane event, and used that data to complete a site design for shoreline protection. Consistent with the analysis, the site design includes the installation of a 15-foot rock revetment (one foot above the 100-year floodplain elevation) constructed with four-foot diameter boulders. The project also consists of replacing a failed elevated timber walkway with a concrete slab-on-grade walkway, restoring portions of the existing bulkhead, clearing invasive plants, and the complete restoration of the failed stormwater basin and outlet.

A rendering of the “Dunes at Shoal Harbor” shoreline protection design by Princeton Hydro.

The plan incorporates natural barriers to reduce the impacts of storm surges and protect the coastal community, including planting stabilizing coastal vegetation to prevent erosion and installing fencing along the dune to facilitate natural dune growth.

These measures will discourage future erosion of the shoreline, protect the residential community from future wave attacks and flooding, and create a stable habitat for native and migratory species.  The project is currently in the permitting phase, and will move to construction when all permits are obtained from local, state, and federal agencies.

This project is an great example of Princeton Hydro’s ability to coordinate multi-disciplinary projects in-house. Our Water Resources Engineering, Geosciences Engineering, and Natural Resources teams have collaborated efficiently to analyze, design, and permit this shoreline protection project. For more information on our engineering services, go here.

How’s the Fishing? Tips for Managing Your Lake’s Fishery

The fishery of a lake is an intrinsic, incredibly dynamic element of a lake system, and managing a lake’s fishery can be a very complex endeavor. There is actually a lot more to it than simply stocking game fish. Although there is no “one way” in fisheries management, there are key guidelines that can be followed to maximize the recreational potential of your lake’s fishery and increase the success of your fishery management and stocking efforts. Over the past two decades, Princeton Hydro has been working with lake, pond, and reservoir managers to help them to align water quality, fishery, and ecological goals.

Princeton Hydro’s Founder, Dr. Steve Souza, recently gave a presentation on fisheries management at the Spring Meeting of the New Jersey Coalition of Lake Associations (NJCOLA). We’ve compiled a few essential elements from his presentation and have made the complete presentation available for free download.

Let’s dive in!

Benefits of a Healthy Fishery

Recreational fishing is an outdoor activity that can be enjoyed by people of all ages. When children are introduced to fishing, it helps cultivate a connection to the environment, thereby promoting outdoor activity and environmental stewardship among today’s youth.

Anglers have always served as important advocates for the conservation of natural resources. The sale of fishing licenses financially supports wildlife habitat conservation and enhancement as well as the protection and improvement of water quality. This increases the ecological services and functions of lakes and adds to their societal and recreational benefits.

A healthy fishery can have significant positive impacts on water quality. In a balanced, healthy fishery the ratio of forage and game fish affects the entire food web, helping to maintain the proper balance of zooplankton and phytoplankton. The “top down” ecological control associated with a balanced fishery minimizes algae blooms, sustains good water clarity and stable water quality. However, when the fishery is out of balance, the water quality and overall ecological health of the lake often suffers.

Before You Stock, Know Your Lake and Start with a Baseline

Before you do any fish stocking, it’s best to conduct a fishery survey. A fishery survey provides the vital data needed to design a stocking and management plan.

A balanced lake fishery is dependent on good water quality, ample habitat, and the correct ratio of predator and prey fish species. A properly designed and implemented fishery survey generates the data needed to quantify the overall composition of the existing fish community (predator vs. prey), the make-up of the forage (food) base, and the density and robustness of the lake’s top piscivores (prized game fish).

The resulting data helps identify if your fishery is balanced, which fish to stock, and how many of each species to introduce. It will also provide the benchmarks needed to solidify your management goals and, later on, help determine if the goals are being met. To stay on track, we recommend that a comprehensive fishery survey be conducted once every three years. Be sure to use the correct types and combination of “active” and “passive” sampling gear and thoroughly sample both the open water and nearshore areas of the lake.

The survey should include the collection and analysis of water quality data, and the mapping of available habitat. Water column water quality “profiles” provide vital information pertaining to the lake’s thermal and dissolved oxygen properties; key factors for a healthy, vibrant fishery. Here are some basic water quality guidelines:

  • Dissolved oxygen: ≥ 4 mg/L with 6-7 mg/L being ideal
  • For warm water fishery: Uniform temperatures at all depth (minimal or no thermal stratification)
  • For cold water fishery: Deep water temperature of 15 C, and dissolved oxygen ≥ 5 mg/L
  • pH: 6 to 8
  • Clarity: ≥ 3 feet (1 meter) Secchi disc transparency
  • Total Phosphorus: < 0.05 mg/L
  • Chlorophyll a: < 20 µg/L

Water quality sampling should also include an assessment of the lake’s zooplankton and phytoplankton communities, the base of your lake’s food web.

Floating Wetland Island

During the survey, take the time to quantify and map the distribution of existing forage, spawning, and refuge habitat. Lack of adequate habitat can significantly impede the fishery’s sustainability. This begins with the bathymetric mapping of the lake, which is basically an underwater survey of the bottom of the lake. This mapping shows where and how much shallow water versus open water habitat exists.  It can also help identify the location and distribution of important habitat types, such as shoals, rock piles, sandy open areas and natural structures (tree falls and snags). The data also helps determine where to create and introduce habitat, which can be in the form of brush piles, floating wetland islands, and other types of features that increase the spawning, recruitment, and foraging success of the fishery.

Stocking Your Lake

Once the fishery survey is completed, habitat is mapped and water quality analyzed, stocking can begin. In order to determine the specific stocking levels and rates that are right for your waterbody, here are some factors to consider:

  • Ensure your stocking efforts create or augment the correct ratio of predator (game) and prey (forage) fish.

  • Stock cautiously, focusing on a simple composition of predator and prey species. For most warm water lakes, largemouth bass should serve as the top predator and fathead minnow should be the primary prey.

  • Avoid problem fish, such as golden shiner, alewife and brown/black bullhead. Although these fish are often promoted as suitable forage species, they can be easily get overstocked and cause major disruptions of the fishery and to the degradation of water quality.

Go here for a more in-depth look at how to properly stock your fishery.

In Summary

A healthy sustainable fishery isn’t only a function of the types and amounts of fish stocked in a lake; it is directly a function of water quality, the availability and quality of spawning, foraging and refuge habitat, the ratio of forage to predator fish, and the overall composition and balance of the food web.

Begin with a fishery survey; the resulting data enables a correctly planned and implemented stocking program. Conduct routine surveys to assess the status of the fishery and the success of the program. Also, annual water quality testing provides the information needed to make wise pro-active fishery management decisions. It will also provide insights into the lake’s environmental conditions to ensure they are supportive of a healthy, productive and sustainable recreational fishery.

Learn More

If you’re interested in learning more about Princeton Hydro’s fisheries management or lake management services, please contact us.

Click here to download a full copy of Dr. Souza’s presentation, titled “How’s the Fishing? Maximizing the Recreational Potential of Your Lake’s Fishery,” which he recently presented at the NJCOLA Spring Meeting. The presentation provides an in-depth set of guidelines for fishery management, covering topics like data collection methods, habitat creation and enhancement, maximizing habitat quality, and details on various stocking species to consider for your lake.

NJCOLA unites lake communities throughout New Jersey through education and by formulating legislation favorable to the protection and enhancement of the State’s lake resources. NJCOLA meetings, held on a regular basis in the spring and fall, educate members on various topics and issues affecting lake communities ranging from legal to environmental.

The Spring NJCOLA meeting was well attended with over 60 participants representing lakes throughout New Jersey, including a number of lakes that are managed by Princeton Hydro – Lake Mohawk, Lake Hopatcong, White Meadow Lake, Lake Swanannona, Kehmah Lake, Culver Lake and Swartswood Lake.

To learn more about Princeton Hydro’s Pond and Lake services, including water quality sampling, bathymetric surveying, floating wetland islands, and fisheries, visit: http://bit.ly/pondlake 

 

CONTEST ALERT: Celebrate #LakesAppreciation Month and Win $100

How healthy is your lake? July is Lakes Appreciation Month and we’re celebrating with a contest! To raise awareness about water quality, we’re encouraging people who enjoy lakes to participate in a “Secchi Dip-In” for a chance to win a $100 Amazon gift card and a one-year membership to the North American Lake Management Association (NALMS).

What is the “Secchi Dip-In”?

The “Secchi Dip-In” is an annual citizen science event created by NALMS in 1994. It was developed in order to involve lake-goers and associations across North America in using a simple Secchi disk to monitor the transparency or turbidity of their local waterway.

This data collected is evaluated on a regional scale by NALMS and helps lake managers further understand the water quality of lakes in their region. Since 1994, more than 10,000 trained volunteers have generated 42,000 transparency records, giving a glimpse of lake water transparency at sites across North America and the world, according to NALMS.

How do I collect a Secchi sample?
  1. What is a Secchi disk and what data is collected with it?
    The typical Secchi disk used in lakes is an 8-inch disk with alternating black and white quadrants. It’s lowered into the water until the observer can no longer see it. The depth of disappearance, called the Secchi depth, is a measure of the transparency of the water. The disk is named in honor of Father Pietro Angelo Secchi, astronomer and scientific advisor to the Pope, who tested this new instrument in the Mediterranean Sea on April 20, 1865.
  2. Where can I get a Secchi disk?
    Secchi disks are a low-cost investment and a great tool to have for measuring water quality. You can purchase a Secchi disk on Amazon or other online marketplaces for $20-$30. Alternatively, you can always ask a friend or your local lake manager to borrow one. Some people even make their own!
  3. How do I take a measurement? How many times do I do it?
    A measurement is taken by lowering the disk on the sunny side of the boat. To eliminate sun glare, an underwater viewer (viewscope) can also be used if so desired. Allow sufficient time (preferably 2 minutes) when looking at the disk near its vanishing point for the eyes to adapt completely to the prevailing luminance level. Record the depth at which the disk disappears. Slowly raise the disk and record the depth of reappearance. The “Secchi depth” is the average depth of disappearance and reappearance. For further accuracy, several people can each record several Secchi depths. Then, all of the depths can be averaged into one single reading. Please note: the water depth should be at least 50% greater than the Secchi depth so that the disk is viewed against the water background, not bottom-reflected light.
  4. What’s the best time of day to collect a sample?  
    The best time of day to collect a sample is when the sun is at its highest point in the sky, generally around midday. Most volunteers generally collect data between the hours of 10:00 AM and 2:00 PM.
  5. What do the results mean?
    The Secchi disk measures transparency, which serves as an indicator of changing water quality. Transparency decreases as the amount of particles in the water— such as algae and sediment—increases.

Check out this “How to Secchi Dip” video created by Princeton Hydro Senior Limnologist Michael Hartshorne:

How to Enter the Contest:

One lucky winner will be randomly selected on August 1, 2018.  The selected winner will receive a $100 gift card to Amazon and a one-year membership to NALMS. We’ll reach out to you via social media to collect your email and address for prize distribution. If the winner does not respond within 5 working days with the appropriate information, we will select another winner at random. Good luck, everyone!

Conditions:

By submitting an entry (Photograph) via Facebook or Twitter to Princeton Hydro’s 2018 #LakesAppreciation Month Contest, you agree to the following: You represent and warrant that:

  • You are the sole and exclusive author and owner of the Photograph submitted and all rights therein; and
  • You have the full and exclusive right, power, and authority to submit the Photograph; and
  • You irrevocably grant Princeton Hydro a non-exclusive, worldwide, royalty-free, perpetual license to use the Photograph in any manner related to the Contest, including all associated use, reproduction, distribution, sublicense, derivative works, and commercial and non-commercial exploitation rights in any and all media now known or hereafter invented, including, but not limited to public relations purposes, posting on social media accounts, and/or for company marketing materials; and
  • No rights in the Photograph have been previously granted to any person, firm, corporation or other entity, or otherwise encumbered such that the prior grant would limit or interfere with the rights granted to Princeton Hydro herein; and
  • No part of your Photograph defames or invades the privacy or publicity rights of any person, living or decreased, or otherwise infringes upon any third party’s copyright, trademark or other personal or property rights.

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.

EMPLOYEE SPOTLIGHT: Meet the Interns

This summer, Princeton Hydro is hosting five interns, each of whom are passionate about protecting water quality and preserving our natural resources. From June to August, our interns will gain professional work experience in a variety of subject areas, ranging from stormwater management to dam restoration to ecological design to lake management and much more. They are assisting on a variety of projects, getting real-world practice in their areas of study, and working with a Princeton Hydro mentor who is helping them gain a deeper understanding of the business of environmental and engineering consulting and setting them up for career success.

 

Meet Our Interns:

 

Ivy Babson, Environmental Science Intern

Ivy is a rising senior from University of Vermont, majoring in Environmental Science with a concentration in Ecological Design, and minor in Geospatial Technologies. In the future, she hopes to implement ecological design in urban areas and create a sustainable environment that would allow future generations to care for and interact with a healthy earth.

Ivy will work alongside Senior Aquatics Scientist Dr. Jack Szczepanski and the Princeton Hydro Aquatics team on projects related to lake and pond management, including fisheries management, data collection and analysis, and water quality monitoring. Recently, Ivy assisted Aquatic Ecologist Jesse Smith in completing an electrofishing survey in a Northern New Jersey river.

Learn more about Ivy.

 

Marissa Ciocco, Geotechnical Intern

Marissa is entering her fourth year at Rowan University where she is a Civil and Environmental Engineering major with a Bantivoglio Honors Concentration. In the future, Marissa hopes to work towards creating a greener and safer environment.

During her internship, Marissa will be mentored by Jim Hunt P.E., Geotechnical Engineer, who has already engaged Marissa in a few construction oversight projects, including a culvert restoration effort in Medford Lakes, NJ and observing geotechnical borings in Evesham, NJ.

Learn more about Marissa.

 

Will Kelleher, Environmental Science Intern

Will is a rising junior at the University of Vermont, studying Environmental Science with a concentration in Water Resources. His current career interests are focused around wetlands restoration and water chemistry. He recently spent two weeks studying water management and sustainable technology in the Netherlands and in the past has helped with biological and chemical stream monitoring with Raritan Headwaters Association.

Mentored by Senior Aquatics Scientist Dr. Jack Szczepanski, Will’s area of focus will be lake and pond management. He’ll spend most of his time in the field alongside members of the Aquatics Team collecting water quality data and mapping aquatic plants, learning about aquatic habitat creation, and implementing various invasive aquatic weed control efforts.

Learn more about Will.

 

Veronica Moditz, Water Resources Intern

We are thrilled to welcome back Veronica, who interned with us last year, and is in her final year at Stevens Institute of Technology, pursuing a Bachelor Degree in Environmental Engineering and a Master Degree in Sustainability Management. She is currently the secretary for Steven’s Environmental Engineering Professional Society chapter. In the future, she hopes to work on more sustainable approach to engineering problems.

Veronica will work alongside Project Engineer and Construction Specialist Amy McNamara, EIT, and Mary L. Paist-Goldman, P.E., Director of Engineering Services, on a variety of environmental engineering projects. Most recently, she assisted with a construction oversight and stormwater management project in Morris County, NJ.

Learn more about Veronica.

 

Tucker Simmons, Water Resources Engineer

Tucker is a Civil and Environmental Engineering major at Rowan University focusing on Water Resources Engineering. His Junior Clinic experience includes the study of Bio-Cemented sand and the Remote Sensing of Landfill Fires. In the future, Tucker hopes to work on creating a more sustainable environment.

Throughout his internship, Tucker will be mentored by Dr. Clay Emerson, P.E. CFM, Senior Water Resources Engineer, and will work on projects related to stormwater management, hydrologic and hydraulic analysis, and various aspects of environmental restoration. He recently assisted with a sink hole inspection in Tredyffrin Township, PA and mapped the water depths of a lake in Bucks County, PA.

Learn more about Tucker.

 

Stay tuned for updates on what our interns are working on!

 

 

 

“Floating Classroom” Launches into Lake Hopatcong

The Lake Hopatcong Foundation (LHF) recently launched its newest initiative – a floating classroom. The custom-built 40-foot education vessel, named ‘Study Hull’, gives students an interactive, hands-on education experience to explore Lake Hopatcong, learn about freshwater ecology, and learn how to protect the watershed.

During its maiden voyage field trip, which was held on May 21, fourth-graders from Nixon Elementary and Kennedy Elementary schools utilized the boat’s laboratory instruments to study water hydrology, temperatures, plankton, and dissolved oxygen levels. They performed a series of tests and experiments designed to help them learn about the general health of the lake. They used Secchi Disks to determine the depth to which light is able to penetrate the water’s surface. They also learned about runoff and nonpoint source pollutants, how to protect the lake’s water quality, and how to be good stewards of the water.

Princeton Hydro helped the LHF design a teaching curriculum on water quality.  Dr. Jack Szczepanski, Senior Aquatics Scientist, and Christopher L. Mikolajczyk, CLM, Senior Project Scientist, trained the staff and volunteers on the curriculum and demonstrated various water quality monitoring techniques that can be conducted with the students.

“We’re really proud to be a part of this exciting initiative,” said Mikolajczyk. “It’s really important to get kids interested in science at an early age and teach them about their surrounding environment – where their drinking water comes from, how it gets polluted, the impacts pollution has on the lake’s ecosystem, and what steps can be made to protect the lake’s water quality. We’re hoping the floating classroom field trip program will make a lasting, valuable impression with these kids.”

In the first year of operation it is expected that the Study Hull will host 1,000 fourth grade students. The long-term goal is to develop lesson plans for students in every grade from kindergarten through high school. Starting in July, the LHF is also offering the public tours of the floating classroom on Mondays at Hopatcong State Park.

The purchase of the floating classroom was made possible by financial support from USATODAY Network’s “A Community Thrives” program, which awarded the LHF with a $50,000 grant. The program recognizes three categories: arts and culture, education, and wellness. In each category, the first place winner received a $100,000 grant and the second and third place winners received $50,000 grants. The James P. Verhalen Family Foundation and the Szigethy Family also provided significant donations to help bring the floating classroom to life.

 

The LHF and Princeton Hydro are longtime partners. Starting back in 1983, Princeton Hydro’s Dr. Stephen Souza conducted the USEPA funded Diagnostic Feasibility study of the lake and then authored the Lake Hopatcong Restoration Plan. That document continues to be the backbone of why and how to restore the lake, manage the watershed, reduce pollutant loading, and address invasive aquatic plants and nuisance algae blooms.

Lake Hopatcong has one of the longest, continuous, long-term ecological databases in New Jersey; almost 30 years of consistently collected water quality data. The data is crucial in assessing the overall ecological health of the lake and proactively guiding its management, identifying and addressing emerging threats, documenting project success (a mandatory element of funding initiatives) and confirming compliance with New Jersey State Water Quality standards.

Princeton Hydro’s most recent work for Lake Hopatcong includes the implementation of green infrastructure stormwater management measures, installation of floating wetland islands to improve water quality, and invasive aquatic plant species management programs, community educational training, and surveys.

For more information about the Lake Hopatcong Foundation or the floating classroom, click here. For more information about Princeton Hydro’s lake management services, go here.