Dam Removal Underway in Watertown, Connecticut

Photo courtesy of the Town of Watertown

As dams age and decay, they can become public safety hazards, presenting a failure risk and flooding danger. According to American Rivers, “more than 90,000 dams in the country are no longer serving the purpose that they were built to provide decades or centuries ago.” Dam removal has increasingly become the best option for property owners who can no longer afford the rising cost of maintenance and repair work required to maintain these complex structures.

Dams can also cause environmental issues such as blocking the movement of fish and other aquatic species, inundating river habitat, impairing water quality, and altering the flow necessary to sustain river life. Removing nonfunctional, outdated dams can bring a river back to its natural state and significantly increase biodiversity for the surrounding watershed.

Currently, work is underway in Watertown, Connecticut to remove the Heminway Pond Dam, which restricts fish passage in Steele Brook, creates a pond with increased water temperatures and high bacterial levels due to high geese populations, and encourages deposition of iron precipitate in the stream channel just downstream of the dam.

Princeton Hydro designed the engineering plans, managed permitting and is now overseeing construction for the removal project. The removal of the Heminway Pond Dam is identified as an integral component in addressing water quality impairment between the dam and Echo Lake Road.

CT DEEP recently published this piece encapsulating the Heminway Pond Dam removal project:

REMOVAL OF HEMINWAY POND DAM ON STEELE BROOK IN WATERTOWN UNDERWAY

Upstream at rock-filled breach in Heminway Pond Dam and shallow, dewatered impoundment on Steele Brook in Watertown (7-18-18)

After almost 15 years of discussion and planning with the Town of Watertown and other partners, removal of Heminway Pond Dam on Steele Brook in Watertown finally got underway in early July.  Though no longer functional, the dam and pond were originally constructed to supply water for a former thread/string mill.  The Town acquired the dam and pond from the Siemon Company, the most recent owner, in 2007 with an eye towards removing the dam, restoring the river and converting the dewatered impoundment area into a passive recreation area, including an extension of the Steele Brook Greenway.  With these goals in mind, the Town approached CT DEEP for help with removal of the dam.

As it turns out, CT DEEP, has also had a strong interest in seeing this dam removed.  It is anticipated that dam removal will improve the hydrology in this section of Steele Brook and eliminate a water quality impairment which manifests itself during hot weather and low flow conditions, as an orange-colored plume of water (due to iron precipitate) immediately downstream of the dam that impacts aquatic life.  Dam removal would also benefit fisheries by restoring stream connectivity and habitat.

Working towards these mutual goals, CT DEEP was able to provide federal CWA 319 nonpoint source grant funding to USDA NRCS to develop a watershed-based plan for Steele Brook to address nonpoint source impairments that includes a dam removal feasibility analysis for Heminway Pond Dam.  Based on the recommendations in this plan, CT DEEP subsequently provided additional 319 grant funds to the Town of Watertown to hire a consultant to develop a dam removal design package, and assist with permitting and preparation.

With the Town of Watertown as a strong and vested partner, CT DEEP is now helping this project over the finish line by providing a combination of 319 and SEP funds to accomplish the actual dam removal and restoration of Steele Brook.  Dayton Construction Company is performing the construction and Princeton Hydro is the consultant overseeing the project on behalf of the Town.  The Northwest Conservation District is also assisting with the project.  It is anticipated that the majority of the work will be completed by this Fall.  U.S. EPA, ACOE and CT DEEP have all played active roles with regard to permitting the project.

 

 

Princeton Hydro has designed, permitted, and overseen the reconstruction, repair, and removal of dozens of small and large dams in the Northeast. Click here to read about a recent dam removal project the firm completed on the Moosup River. And, to learn more about our dam and barrier engineering services, visit: bit.ly/DamBarrier.

September Events Spotlight: Webinars, Conferences & Film Festival

Princeton Hydro is proud to participate in a number of conferences, events, and webinars throughout September:

 

September 6 at 12 pm: “Social Media Hacks” Webinar for the Society for American Military Engineers (SAME) Young Member Council 

SAME Young Member Council is hosting a webinar that will offer solutions for boosting social media presence and increasing engagement. Designed for social media beginners and experts alike, the webinar titled, “Social Media Hacks,” will be presented by Dana Patterson, Communications Strategist for Princeton Hydro. Participants will learn about creating successful social media strategy, utilizing free social media management tools, tracking social media analytics, and executing high-quality posts on various social media platforms. The webinar is free for SAME Members and $25 for all non-members.

Learn more and register.

 

September 9: Wild & Scenic Film Festival On Tour

Hosted by Musconetcong Watershed Association, the “Wild & Scenic Film Festival On Tour” celebrates the 50th Anniversary of the Wild and Scenic Rivers Act by bringing communities together to screen films that call attention to local and global environmental issues. The Hackettstown, NJ tour event, which Princeton Hydro is a proud sponsor of, will feature 11 short films including River Connections, a film that explores the importance of free-flowing rivers and highlights the recent Hughesville Dam removal project. An interactive panel event will follow the film screening and feature experts including MWA Executive Director Alan Hunt, Ph.D. and Princeton Hydro President Geoffrey Goll, P.E., who were both interviewed in the film. This event is free and open to the public, but registration is required.

Learn more and register.

 

September 12: Schuylkill Action Network’s (SAN) Water Utility Forum

This year’s SAN Forum will cover a variety of water-quality related topics, including perfluorinated compound (PFCs) and upcoming drinking water regulations. The forum will provide a platform to collaborate and share information, expertise, and technology to help achieve a shared vision of clean water and a healthy environment for the Schuylkill River and its tributaries. A variety of presentations will be offered during the forum, including one by Dr. Fred Lubnow, Director of Aquatics Programs for Princeton Hydro, on the topic of Harmful Algal Blooms (HABs).

Learn more and register.

 

September 15: Mercer County Park Commission’s River Days

Join Mercer County Park Commission for “River Days,” a free, family-friendly event at the Tulpehaking Nature Center with trail activities, arts and crafts, a raffle, and a neighborhood cookout on the back lawn of the nature center. Check out the Princeton Hydro air boat and chat with our Aquatics Field Director about the upcoming multi-year restoration of freshwater tidal wetlands in John A. Roebling Memorial Park. The restoration project is a partnership between Mercer County, New Jersey, Mercer County Park Commission, and Princeton Hydro.

Learn more.

 

September 23-26: 91st Annual Water Works Operators’ Association of Pennsylvania (WWOAP) Conference

WWOAP is hosting its 91st annual conference, which offers a diverse collection of professional presentations, workshops, networking events and an exhibit hall. Princeton Hydro’s Director of Aquatics Programs  Dr. Fred Lubnow is presenting on “Managing HABs and Their Associated Cyanotoxins in Raw Water.” Other presentation topics include “What Might Climate Change Look Like in Pennsylvania,” “A Multi-Lateral Approach to Water Loss Reduction,” and “Achieving Water Quality Optimization.”

View the full conference program.

 

September 25: New England Interstate Water Pollution Control Commission (NEIWPCC) Research Webinar

NEIWPCC is offering a free research webinar on modeling and flood-mitigation recommendations for a forested and urban Hudson River tributary watershed. The webinar takes a look at the Moodna Creek Watershed and Flood Mitigation Assessment and describes how flood models were used to inform recommendations for reducing and mitigating existing and anticipated flood risk. The assessment was conducted by environmental consultants at Princeton Hydro and GreenVest, and funded by NEIWPCC through the New York Department of Environmental Conservation’s Hudson River Estuary Program. This free webinar will be presented by Christiana Pollack, GISP, CFM, Environmental Scientist & GIS Manager for Princeton Hydro, and Jessica Jahre, CFM, AICP.

Learn more and register.

 

September 28: Alliance for NJ Environmental Education (ANJEE) Autumn Conference

Duke Farms will host ANJEE’s Autumn Conference, titled “Imagine a World Outdoors.” The conference, which takes place completely outdoors and does not include a single PowerPoint presentation, invites environmental education professionals throughout New Jersey to come together to collaborate around innovative ideas, learn and disseminate best practices, and network. Participants will explore natural history with local experts in birding, animal tracking, and plant identifying and learn trade secrets from experienced outdoor teachers who will share their methods and techniques. Princeton Hydro’s Dana Patterson and Pinelands Adventures’ Danielle Odom are teaching a workshop on “How to Bring Out the Inner Bird Nerd in your Students. ANJEE hopes the event will inspire participants to become more informed and dedicated stewards of the land.

Learn more and register.

 

Stay tuned for more event updates!

Creative, Timely Solutions Lead to Successful Dam Repair in Medford Lakes

By Kevin Yezdimer, P.E. and Jim Hunt, P.E.

Just 25 miles east of Philadelphia, on the edge of the New Jersey Pinelands region, sits a network of 22 lakes that serve a multitude of recreation purposes for the residents of Medford Lakes. Serving as the guardian to these natural beauties is the Medford Lakes Colony (MLC), a private homeowner association. Homeowners in this community contribute to a “Lake Restoration Fund,” managed by MLC, which is used to maintain the water control structures and monitor the water quality for the bodies of water within the community. This dedicated fund is often used for dredging of the lake beds; repairs and replacement of dams, spillways, and culverts; installation of aerators or fountains to promote long-term benefits to water quality; treatments for weeds and algae; and the maintenance of the coves and beaches.

In mid-April, a concerning blockage developed in Lake Wauwauskashe Dam’s spillway and water was backing up at the upstream outlet structure. The 30-inch wide corrugated metal pipe serves as the dam’s primary (and only) outlet under Wagush Trail, a neighborhood road connecting Lake Wauwauskashe and Lake Mushkodasa. During the attempt to clear the mass of accumulated woody-debris via vacuum truck extraction, a previous repair consisting of a 5’ segment of corrugated plastic pipe had been dislodged and expelled from the downstream end of the spillway. With a compromised dam and flooding in the forecast, MLC acted immediately to handle this emergency dam repair.

Primary Spillway Inlet
Before – Upper portion of the existing corrugated metal pipe was collapsed. After – Pipe was slip-lined and the annulary space was grouted.

 

Given Princeton Hydro’s long-term history of inspecting and maintaining dams and levees in Medford Lakes, MLC contracted our experts to assist. The next day, our team of geotechnical engineers were on-site to investigate the situation. To facilitate the inspection and minimize the stress/pressure on the dam, the upstream and downstream lakes were lowered via an NJDEP Fish and Wildlife Lake Lowering Permit. Additionally, a video inspection of the compromised culvert pipe was conducted. Our geotechnical team observed that the upstream portion of the pipe had collapsed and the structure was experiencing significant seepage (i.e. water flowing through undesirable paths through the dam with the potential for soil piping and stability failure).

Primary Spillway outlet
Before – The existing corrugated metal pipe had corroded and erosion had taken place around the outlet. After – Pipe has been slip-lined and outlet protection (riprap) was installed to stabilize the surrounding soil.

 

With the risk of potential dam failure, Princeton Hydro immediately kicked-off coordination with the NJDEP Bureau of Dam Safety, NJDEP Division of Land Use Regulation, the Pinelands Commission, and the Borough of Medford Lakes. Our licensed engineers promptly developed the repair concept and associated scope of work, detailing our proposed means and methods for the emergency repair.

“We take the potential risk of dam failure very seriously, as safety is one of our core values,” said Kevin Yezdimer, P.E. Director of Geosciences Engineering at Princeton Hydro. “Our geotechnical team prioritized the design, permitting, and implementation of this emergency repair to assure the safety of our client and the community.”

Injection grouting underway (Grout pressure is monitored during placement & the ground surface is monitored for signs of heave).

This included addressing the collapsed pipe; utilizing cementitious injection grouting and compaction grouting to eliminate seepage pathways and stabilize the earthen dam in-place; and provide spillway outfall protection. Through private solicitation, Princeton Hydro selected Compaction Grouting Services, Inc. as the specialty contractor to perform the repair.

A considerable volume of water was required to prepare the grout mixes, and no water sources were available adjacent to the project site. Seeking out solutions, MLC proposed the unique idea of using reclaimed wastewater from the local wastewater treatment plant. Our team confirmed that reuse of the reclaimed wastewater was indeed within the guidelines of the “Technical  Manual for Reclaimed Water for Beneficial Reuse,” and we successfully facilitated approval to use it with NJDEP Division of Water Quality.

Placement of cellular fill into the hollow concrete structure is underway. A lightweight foaming agent was added to the grout mix within the concrete truck. The lightweight grout was then pumped into the structure.

As the construction effort ramped-up, some complications arose. By design, this unique structure allows water flow over the dam’s weirs and drops 8 to 10 feet vertically before travelling under the roadway through the primary spillway. Above the primary spillway is a concrete structure that spans from the upstream lake to the downstream lake and immediately beneath the local roadway. It was discovered that this 50’ long, 6’ deep, concrete structure was hollow and served as a potential seepage pathway. Princeton Hydro proposed to fill-in the hollow structure with a lightweight cellular fill material in order to cut-off the potential seepage pathways, eliminate the 6’ deep hollow chamber beneath the roadway, and facilitate a long-term repair solution.

Implementation of this strategy was further complicated when a utility markout and a subsequent video inspection of the hollow structure confirmed that a gas line passed through the structure on the downstream side of the roadway. Princeton Hydro coordinated with South Jersey Gas to disconnect the gas line in order to minimize risk during construction and eliminate future complications. The neighborhoods on either side of the dam were fed redundantly, so their service was not interrupted during this process.

Overall, the emergency dam repair solution involved an in-situ soil stabilization of an earthen embankment dam via compaction/injection grouting, slip-lining the primary spillway, stabilization of the downstream outlet, and utilization of reclaimed wastewater as a water source for on-site grout batching. The following was completed by our team and contractors during the course of the emergency construction:

  • Slip-lining of the failed 30-inch pipe using a smooth, slightly smaller in diameter high density polyethylene pipe (HDPE) pipe inside of the existing pipe, providing an equal or greater hydraulic capacity as that existing;

  • Grouting of the annular space between the new and old pipes;

  • Non-woven geotextile fabric and riprap outfall protection were placed around the downstream outlet of the culvert pipe to provide scour protection;

  • Compaction and injection grouting was performed in multiple locations. The compaction grout utilized a “low-slump” mix while the injection grout utilized a much more mobile or fluid mix allowing for filling of existing seepage pathways or soil voids, and;

  • Approximately 44 cubic yards of lightweight cellular-grout backfill was utilized to fill in the hollow concrete structure beneath the roadway completing the emergency repair without the need for complete outlet structure or earthen dam reconstruction.

Lowering New Pipe Into Place

Creative, innovative solutions paired with timely coordination and expertise drove the success of the Lake Wauwauskashe Dam emergency repair.

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 dam and barrier engineering services, visit: bit.ly/DamBarrier.

Kevin M. Yezdimer, P.E., Princeton Hydro’s Geoscience Engineering Director, is a multidisciplinary professional civil engineer who holds degrees in both Geology and Civil Engineering, and has 11 years of progressive and varied work experience as both a design consultant and project owner with Geotechnical & Construction Engineering being his core area of expertise. He has significant experience performing soil and rock core sampling programs, infiltration testing, soils laboratory testing, foundation design (shallow and deep), preparation of construction recommendations,  and overseeing construction review activities (e.g., earthwork, foundations, concrete, masonry, structural steel, roadway, and utility construction).

 

Jim Hunt, P.E., joined Princeton Hydro in 2017 as a Geotechnical Engineer and provides a wide range of engineering services for the firm including: subsurface explorations, bearing capacity and settlement analyses, slope stability analysis, stability analysis of existing structures, preparation of technical deliverables, and cost estimating.

 

 

 

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:

Five Ways to Participate in Lakes Appreciation Month

#LakesAppreciation Month is a great time of year to enjoy your community lakes and help protect them. 

Lakes Appreciation Month was started by North American Lake Management Society (NALMS) to help bring attention to the countless benefits that lakes provide, to raise awareness of the many challenges facing our waterways, and encourage people to get involved in protecting these precious resources.  Unfortunately, the natural beauties that provide clean drinking water and wildlife habitat are at risk. Chemical pollutants, hydrocarbons, stormwater runoff, invasive aquatic species, and climate change are just a few of the the serious threats facing freshwater habitats.  So what can you do to to help?

We’ve put together five tips to help you celebrate Lakes Appreciation Month and get involved in protecting your favorite lakes:

1. Join the “Secchi Dip-In” contest: The “Secchi Dip-In” is an annual citizen science event where lake-goers and associations across North America use a simple Secchi disk to monitor the transparency or turbidity of their local waterway.  This year, Princeton Hydro is offering “Secchi Dip-In” participants a chance to win a $100 Amazon gift card and a one-year membership to NALMSEntry details here.

2. Organize a cleanup event: You can easily organize a lake clean-up in your community! Volunteer cleanups are a great way to get neighbors together around a good cause, raise awareness about the importance of protecting water quality, and make a positive impact on your community waterways. Organizing a volunteer event is a lot easier than you may think. Check out these tips for how to get started.

3. Get involved with your local lake: You can help support your favorite lake by joining a lake or watershed association. As an organized, collective group, lake associations work toward identifying and implementing strategies to protect water quality and ecological integrity. Lake associations monitor the condition of the lake, develop lake management plans, provide education about how to protect the lake, work with the government entities to improve fish habitat, and much more.

4. Monitor and report algae blooms: With the BloomWatch App, you can help the U.S. Environmental Protection Agency understand where and when potential harmful algae blooms (HABs) occur. HABs have the potential to produce toxins that can have serious negative impacts on the health of humans, pets, and our ecosystems. Learn more and download the app.

5. Get outside and enjoy: Whether you enjoy swimming, relaxing on the shoreline, canoeing, or fishing, there are countless ways you can get outside and enjoy your community lakes. Encourage others to appreciate their local waterbodies by taking photos of your lake adventures and sharing them on social media using the hashtag: #LakesAppreciation.

 

Go here to learn more about NALMS and get more ideas on how to celebrate your local lakes. If you’re interested in learning more about Princeton Hydro’s broad range of award-winning lake and pond management services, please contact us. 

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.

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.

A Scientist’s Journey to the Antarctic: A Princeton Hydro Blog Series

This two-part blog series takes us on an adventure to the southernmost continent and explores how changes to Antarctica’s ecosystem have worldwide impacts.

Welcome to Part Two: The Continent of Science

Antarctica, the most remote and inaccessible continent in the world, is also, on average, the coldest, windiest and driest continent. Quick Fact: Antarctica is actually a desert! Additionally, with an average elevation of about 7,200 feet above sea level, it is also the world’s highest continent.

There are no native people in Antarctica, but scientists from all over the world visit the continent to conduct research. During the summer, approximately 4,000 scientists visit “the continent of science” to carry out research in a wide range of physical and biological sciences – from the vastness of space to the minutest scale of microorganisms. The research conducted here has helped to highlight global problems, including climate change.

Tourists also visit Antarctica during the summer to enjoy the spectacular scenery and abundant wildlife. In Part One of our two-part blog series, we take you on an Antarctic journey through Sophie Breitbart’s experience aboard the National Geographic Explorer ship. Sophie saw a variety of wildlife during her 10-day educational excursion, including Crabeater and Leopard seals, gentoo and Chinstrap Penguins, Humpback and Killer whales, migrating Red Knots, and more.

Polar tours like the National Geographic Lindblad Expedition help to raise climate change awareness and create lifelong wildlife ambassadors, and the profits from responsibly managed tourism help to fund critical scientific expeditions to the Antarctic.

Just last year, a research mission conducted by the National Oceanic and Atmospheric Administration discovered that sea ice cover in the Antarctic is near record lows – 18.2%, or 520,000 square miles, below the 1981-2010 average. That is the second lowest sea ice report since record-keeping began in 1979, with the first being recorded in 2016. Smaller ice shelves in the Antarctic Peninsula are currently retreating, breaking up into vast fields of icebergs, likely due to rising temperature and surface melting.

Snow and ice make up more than 95% of Antarctica’s surface terrain. The continental ice sheet contains approximately seven million cubic miles of ice, representing about 90% of the world’s total ice. The average thickness is about 1.5 miles. To understand its extent, if Antarctica’s ice were to melt today, global sea levels could rise 150 – 200 feet. It’s massive.

Climate change impacts are already being documented in Antarctica. The Antarctic Peninsula’s glaciers have been warming faster than the rest of the continent. As the snow and ice decrease, the land cover increases and absorbs more heat, which in turn increases the rate of warming. In 2017, a study published in Current Biology found that over last 50 years, temperatures have been rising, and therefore have caused a steady growth of moss on the continent.  So, scientists are now predicting that, “terrestrial ecosystems will alter rapidly under future warming, leading to major changes in the biology and landscape of this iconic region—an Antarctic greening to parallel well-established observations in the Arctic.”  And, another study by researcher Bill Fraser has reported that Adélie Penguin populations have decreased from 32,000 breeding pairs to 11,000 in 30 years because of the changes in temperature.

Changes to the global sea ice cover reported by NOAA not only carry major implications for the continent of Antarctica, but for the entire world. 97% of actively publishing climate scientists agree that earth’s climate is warming, and the evidence that the Arctic’s ice caps are melting at an accelerated rate due to climate change is blaring. And, more than 62% of Americans say they are at least “somewhat worried” about global warming. Yet, not many people are taking daily actions to slow global climate change.

We must make every effort we can to limit our own carbon footprint and mitigate climate change. It has been said that there are most likely no greater ambassadors for Antarctica than the tourists who have been there and return home to share information about the need for its protection.

When Sophie returned from her trip, she said “I became an environmental scientist because I have a passion to conserve biodiversity. Being immersed in this wild place and experiencing firsthand the magnificent yet fragile Antarctic landscape acts as a reminder of why it’s so important to do this work. Those memories inspire me to keep at it.”

To learn more about Antarctica and what scientists with World Wildlife Fund are doing to protect it, go here. If you have any questions for Sophie about her journey, please email us or comment below.

 

Sophie Breitbart worked for Princeton Hydro from March 2016 until May 2018, first as an intern and then as a staff scientist. She is now pursuing her PhD in Ecology and Evolutionary Biology at the University of Toronto, where she will study how urban development affects the ecology and evolution of interactions between the plant common milkweed, its herbivores, and pollinators.

 

A Scientist’s Journey to the Antarctic: A Princeton Hydro Blog Series

A trip to Antarctica has long been at the top of the bucket list for Sophie Breitbart, former Staff Scientist at Princeton Hydro, and her father. Ultimately inspired by the extraordinary spirit of adventure in “South: The Endurance Expedition,” the story of British explorer Ernest Shackleton‘s 1914 attempt to reach the South Pole, the two decided that it was time to make the journey to the white continent. What they experienced was far more than a travel dream fulfilled.

This two-part blog series takes us on an adventure to the southernmost continent and explores how changes to Antarctica’s ecosystem have worldwide impacts.

Part One: Antarctic Adventure

The National Geographic Lindblad Expedition trip began with a flight to Buenos Aires, Argentina, where Sophie and her father met up with the other travelers and an expedition crew that consisted of an exploration leader, eight veteran naturalists, a National Geographic photographer, a Lindblad-National Geographic certified photo instructor, an undersea specialist, a Global Perspectives guest speaker, and a video chronicler.

Ushuaia, Argentina

In Buenos Aires, the group, totaling approximately 140 people, boarded a private charter flight to Ushuaia, Argentina, the world’s southernmost city. After taking in views of the Martial Mountains and the Beagle Channel, which is commonly referred to as The End of the World, the group climbed aboard the National Geographic Explorer ship and set sail for a 10-day Antarctic adventure.

The National Geographic Explorer is a 367-foot expedition ship that accommodates 148 guests in 81 cabins. The Explorer is uniquely equipped with an ice-strengthened hull, advanced navigation equipment, a variety of exploration tools, and vast expanses of windows that provided the ultimate vantage point for spotting dolphins and sea birds as the ship left the Beagle Channel.

Before reaching the Antarctic, the ship would have to pass through the infamous Drake Passage, the body of water between Cape Horn in South America and the South Shetland Islands in Antarctica, where the Atlantic, Pacific, and Southern seas converge. Because the currents in the Passage meet no resistance from any nearby landmass, they can be some of the choppiest waters in the world. Luckily for Sophie and the other Explorer travelers, the Drake Passage was cooperative for the most part and the journey through it was relatively smooth. (Editor’s Note: The journey back was another story.)

On day five of the journey, the ship arrived in the Antarctic Peninsula.

“The ice was so shocking and jaw-dropping,” said Sophie reflecting on her first impression of Antarctica. “I had never seen anything like it before. There were so many different shades of blues and whites and countless textures. It was truly incredible to see.”

With close to 24 hours of daylight, the exploration opportunities were endless. Sophie and her father participated in kayaking tours, expeditions on an 8-person zodiac boat, around the clock wildlife watching, and even a few hikes on the Antarctic Peninsula. There they saw indigenous rocks and artifacts, remnants of British research stations from the 1950s, and lots of wildlife, including nesting South Polar Skua Birds, penguins swimming and jumping out of the water, and a playful group of Leopard Seals.

Humpback and Killer whales skirted the ship as well. A Killer Whale research team aboard the Explorer took blow samples, which would be genetically sequenced, and shared  with passengers their aerial imagery findings, which they captured in order to record the whales’ dimensions, family structures, and health. Sophie and her father enjoyed a variety of whale sightings. During one of their kayaking expeditions, a large Humpback Whale surfaced just 10 feet away from them, then swam right underneath the kayaks and resurfaced, showing lots of playfulness and curiosity.

Check out this incredible video showing a fascinating strategy that killer whales use to hunt seals:

While Sophie struggled to choose a favorite moment from the trip, she quickly recalled the memory of kayaking along the coast of the Antarctic Peninsula among a field of stunning icebergs. “They each possess a unique mixture of color, density, shape, and size… like pieces of artwork, truly breathtaking in their composition and enormity.” Another easy highlight: “One day, the captain lodged our ship into an ice floe and we had a cookout complete with BBQ and lawn chairs. Definitely a once-in-a-lifetime experience.”

Sophie described this journey as the “most amazing scientific field trip” she’s ever been on. It left her feeling inspired to continue her work as an environmental scientist and acted as a reminder about why it’s so important to continue to be involved with projects that conserve biodiversity and protect water resources.

Check out Part Two of this Princeton Hydro blog series.

 

Sophie Breitbart worked for Princeton Hydro from March 2016 until May 2018, first as an intern and then as a staff scientist. She is now pursuing her PhD in Ecology and Evolutionary Biology at the University of Toronto, where she will study how urban development affects the ecology and evolution of interactions between the plant common milkweed, its herbivores, and pollinators.