The Ecogeomorphic Evolution of Louisiana’s Wax Lake Delta

By Brittany Smith, Environmental Scientist at Princeton Hydro 

As a graduate student in the geology program at the University of Texas at Austin, I worked on a study that used remote sensing to explore links between coastal geomorphology and ecology at the Wax Lake Delta in Louisiana. In this blog, I provide a snapshot of my research, which was recently published in the journal Remote Sensing.

 

What is the Wax Lake Delta?

The Wax Lake Delta is a small, young river delta in Louisiana that began growing in the 1940s after the construction of the Wax Lake Outlet. In 1941 the U.S. Army Corps of Engineers dug the Wax Lake Outlet from the Atchafalaya River – it extended out to the coastline and was designed to reduce the severity of floods in nearby Morgan City.

Image by NASA/Jesse Allen: While the Mississippi River Delta has been washing into the Gulf of Mexico and receding just to the west the Wax Lake and Atchafalaya River deltas (pictured above) are growing. Satellite imagery shows how the deltas have grown between 1984 (left) and 2014 (right).

This outlet provided a constant flow of water to be diverted from the river before reaching the banks of Morgan City, which had experienced several devastating floods. Approximately 40 percent of the Atchafalaya’s discharge gets channeled through the Wax Lake Outlet, which has the capacity to carry a maximum of 440,000 cubic feet per second.

Following the creation of the Wax Lake Outlet, the turbulent flow of water began to carry sediment down the outlet, which deposited at the mouth of the outlet and, over time, caused an underwater delta to grow. In just over 40 years, the Wax Lake Delta grew from nothing to an area twice the size of Manhattan. Research shows that it receives 34 million tons of sediment per year. Today, it spans roughly 7 miles out into the Gulf of Mexico and provides valuable habitat for a variety of animals.

 

The Why Behind the Research

Many coastal areas have been retreating or drowning as a result of subsidence and decreased sediment availability due to upstream dams and levees. According to the Population Reference Bureau, “Today, approximately 3 billion people — about half of the world’s population — live within 200 kilometers of a coastline. By 2025, that figure is likely to double.”

This population is increasingly vulnerable to flooding and erosion due to sea level rise and storms, especially in coastal Louisiana, where land loss is prevalent due to subsidence and decreased sediment supply.

The Wax Lake Delta is one of the few places in coastal Louisiana that is building rather than losing land, so is seen as an example of processes that could be applied elsewhere on the Gulf Coast to mitigate subsidence and restore coastal wetlands. Additionally, it is an ideal study site because it is relatively small, young enough that it has a good historic record, and has been largely unaltered by human activities.

This image depicts the study area: (a) The Wax Lake Delta (WLD, red square) is located at the terminus of the Wax Lake Outlet (blue line), which diverts water from the Atchafalaya River (purple line) in the U.S. state of Louisiana. The Atchafalaya is a distributary channel for the Mississippi (green line) and Red (red line) Rivers. (b) Image of WLD from 28-Sep-2010 by Landsat [88], for water level y = 0.35 m (NAVD88) at Camp Island gage (yellow dot) [93]. (c) Image of WLD from 24-Apr-2011 by Landsat [88], for water level y = 0.67 m (NAVD88) at Camp Island gage. WLD Pintail Island test case area outlined in white.

 

The Research in a Nutshell

Elevation is a very important variable in coastal ecosystems, as it controls how frequently a site is flooded. This in turn controls how frequently sediment can be delivered or removed from the site, and also what type of vegetation will grow there.

To understand how the Wax Lake Delta is growing, it would be ideal to have an understanding of how the topography has changed over time. Unfortunately, very little elevation data was available for the Wax Lake Delta, so I had to develop an indirect way of getting this information.

Photo Credit: Field and StreamWhat I did have available was a significant amount of Landsat satellite imagery. This was useful to me for two reasons: the delta is extremely flat and low-lying (less than 3 feet above sea level), and the tidal cycle typically fluctuates between 0-3 feet above mean sea level. This means that since each satellite image is taken at a different water level, different parts of the delta are exposed above the water in each picture. Taken together as a group over time, we can start to get a sense of which areas are higher and more likely to be exposed, and which areas are more likely to be flooded, and therefore at a lower elevation.

To do this in a quantitative way, I took all the images taken over a three year period and converted them to binary images, where land was classified as 1, and water classified as 0. I then added the images together, to create a composite image where pixels with higher values corresponded to areas that were exposed more frequently, and pixels with lower values were more frequently flooded.

Using water level data from a USGS gauge station that was installed at the delta in late 2008, I was able to develop a probability distribution of water levels. Taking these together – a probability map of flooding frequency and a probability distribution of water level elevations – I was able to create topographic maps based on the Landsat satellite imagery.

By performing this method over a number of years, patterns emerge about how the delta is evolving over time. The island changes from a relatively amorphous, unorganized shape to a defined outer levee and inner island platform.

Photo Credit: The National Wildlife FederationA deeper knowledge of the delta topography, allows us to look at connections to the delta ecology. We know that elevation controls hydrology and therefore plant growth, but we have also seen situations where plants can in-turn affect elevation by contributing organic matter to the soil, preventing erosion due to the root mat, or trapping sediment with their stems when sediment-laden water flows through.

In the case of salt marshes, previous studies have shown that if there is a feedback between the two, it occurs because a) plants tend to be most productive at a specific elevation and b) plants are in some way contributing to sediment accumulation relative to their productivity.

Photo Credit: USGSFor example, if a plant grows best at an elevation of two feet, it grows really densely at two feet, contributes more organic matter to the soil, bigger roots grow that help increase cohesion and reduce erosion, and the stems are denser and trap more sediment when the area is flooded. These all help increase the elevation of the marsh over time. However, if the elevation starts to get too high, the plant grows less densely, contributes less to the marsh surface, and the elevation will drop back down until the plant is happy again. Over time, the surface of the marsh will start to organize around these ideal elevations, creating a terraced effect with platforms corresponding to different plant types that do particularly well at that elevation.

When we look at how a transect down the center of the delta island has changed over time, we see that it goes from a relatively smooth, straight line, to a stepped system comparable to the models from other studies. When we compare the elevations of these platforms to the vegetation communities at the delta, we find that they correspond positively to high-marsh and low-marsh plants. This suggests that there is feedback occurring between plants and sediment accumulation at the delta.

 

In Conclusion

This research a) developed a new approach for investigating changes in coastal topography using satellite imagery, and b) confirmed that there is likely to be feedbacks between sediment deposition, marsh elevation, and vegetation growth. These feedbacks should be considered in any coastal wetland restoration and land building efforts.

 

Brittany Smith is an Environmental Scientist with an extensive background in hydrology and ecology. At Princeton Hydro, she has been involved in a wide variety of projects including stream assessments, wetland water budget modeling, soil field assessments, GIS analysis, permitting, and aquatic ecology. She holds a Master of Science in Geology with an emphasis in hydrology and geomorphology from the University of Texas at Austin, and a Bachelor of Science in Plant Biology from the University of California at Davis. Brittany has strong skills in data analysis and management, as well as experience in a broad range of field and laboratory techniques.

 

Community Science on the Schuylkill River

The nonprofit Schuylkill River Greenways, in partnership with Berks Nature, Bartram’s Garden, The Schuylkill Center for Environmental Education, Stroud Water Research Center, and Princeton Hydro, is kicking off a Water Quality Monitoring Project for the Schuylkill River on World Habitat Day, Monday, October 5, 2020. This project, focused on the main stem of the river from Berks Nature in Reading to Bartram’s Garden in southwest Philadelphia, is aimed to document the current ecological status and health of the river and seeks to engage and educate a diverse set of river users and residents.

“An important aspect of our mission is to connect communities to the Schuylkill River through recreational and educational activities,” said Tim Fenchel, Deputy Director of Schuylkill River Greenways. “To fully achieve the river’s potential, we must help the public understand the current health status and what they can do to continue to improve its quality for this generation and generations to come.”

In order to monitor the presence and/or distribution of litter along the Schuylkill River, the team is launching a campaign to recruit “Community Scientists” to conduct 5-minute Visual Monitoring Assessments. Using their mobile device, these volunteers can simply record the trash accumulation or dumping points along a 100-foot section of the Schuylkill River via a user-friendly form accessed via a cell phone: bit.ly/litterform.

“Trash is important to address when talking about the health of a waterway because it’s often the most visually obvious form of pollution. Bacterial and chemical pollution are generally less directly observable, but when we see trash, it instantly informs our impression of a body of water,” said Chloe Wang, River Programs Coordinator at Bartram’s Garden. “And, it can point to larger problems. For example, near Bartram’s Garden, a lot of trash washes into the river from combined sewer overflows, which also introduce harmful bacteria into the water. It will be interesting to see how the presence of trash differs along various stretches of the Schuylkill.”

The Community Scientist visual assessments require no formal training and are meant to be a simple effort that any resident can complete. We’ve developed an assessment survey, which can be accessed and submitted via a smartphone or tablet by opening the link in the phone/tablet’s browser.

“This is an opportunity for anyone with an interest in the Schuylkill River to spend time on the river and provide valuable feedback on the conditions of the river,” said David Bressler, Project Facilitator at Stroud Water Research Center. “Schuylkill River Greenways and its partners in this project are looking for motivated and dependable individuals to help them learn about the Schuylkill River and move in positive directions toward making the river more accessible to the community. Support from volunteers is very important and is greatly appreciated.”

The goal is to document critical areas of trash accumulation or dumping points in order to guide management efforts to better deal with this pollution. In addition to the multiple-choice questions to rank trash levels and quantities, this platform asks volunteers to submit a photo of the area and collects the GPS location. By utilizing this user-friendly platform, the data collected under this effort will be summarized and visualized by the project team.

“This project is an important study that we can use to connect people back to the river and show that the Schuylkill River is a place to be enjoyed by the entire community surrounding it and beyond,” said Michael Griffith, Education & Watershed Specialist at Berks Nature.

In 1985 the United Nations designated the first Monday of October every year as World Habitat Day. The idea is to reflect on the state of our towns and cities and the basic right of all to adequate shelter and to remind the world of its collective responsibility for the future of the human habitat. By understanding and improving water quality in the Schuylkill River, we are creating a place that enables community members to access public green and open spaces. This effort also supports UN Sustainable Development Goal 11, which aims for resilient, inclusive, safe, diverse cities by 2030.

In addition to the Community Scientist visual assessments, the stakeholder team is conducting water quality sampling and monitoring over the next year at four locations along the main stem of the Schuylkill River. This scientific documentation of critical water quality parameters will be performed by the stakeholder group’s employees and long term volunteers, who are trained in data collection and scientific methods. We will collect data on bacterial concentrations in the river using a combination of 3-M Petrifilm kits and laboratory-based analytical measures. In addition, in-situ temperature, oxygen, pH, and turbidity data will be collected utilizing Mayfly dataloggers.

“Our research shows that residents care about the river, but are not confident whether it is clean or safe to use for recreational activity. So we’ve designed a volunteer survey and scientific water quality assessment to document the ecological health of the Schuylkill River,” said Michael Hartshorne, Aquatic Resources Project Manager at Princeton Hydro. “By studying bacterial inputs and identifying hotspots for trash, we can communicate the status of the river, provide recommendations on areas of improvement, and ultimately, change the current public perception of the river.”

For the water quality monitoring, Princeton Hydro scientists will provide training to the partner nonprofit organizations’ staff and review the methods and protocols to assure the highest level of quality. This long-term data collection effort is slated to begin this month and continue for approximately one year. The results of this assessment will allow us to determine potential hotspots related to nutrient and bacteria inputs and to understand the overall ecological health of the Schuylkill River.

Overall, through this effort, the stakeholder team hopes to connect residents and communities with the Schuylkill River and to encourage engagement with this special resource.

Our 2020 Earth Day Photo Contest Winner!

In honor of Earth Day, Princeton Hydro held its annual Photo Contest with the theme “Human Impact” for its employees. We’d like to thank everyone who submitted photos this year. Overall, we received 27 gorgeous submissions from our staff.

All photos were rated on the following criteria by three volunteer judges: Danielle Odom, Lucy Aquilino, and Amanda Brooks (see bios below).

  • Technical Quality (30%)
  • Originality (30%)
  • Artistic Merit (40%)
THE WINNER OF THE PRINCETON HYDRO 2020 EARTH DAY PHOTO CONTEST IS…

“Welcome Home” – Although its a local and small impact, I intentionally leave dead wood in sunny places on my property. This ensures that I always have an Eastern Fence Lizard like this big female to greet me when I come home. Southern New Jersey. By Clay Emerson.

Scroll to the bottom to see a gallery of runner-up photos.

ABOUT THE JUDGES:
DANIELLE ODOM

Danielle is a Staff Scientist II at the Academy of Natural Sciences of Drexel University. Her career is dedicated to watershed monitoring research and her responsibilities include both field and laboratory work. She has specialized in studying biological indicators as a parameter to track stream health via macroinvertebrate taxonomy; in particular identifying members of the non-biting midge family Chironomidae. Once an experiential outdoor educator, she taught nature photography to middle school students as a pathway to understanding different perspectives and the impact of humans on the environment, a la Ansel Adams.

Lucy Aquilino

Lucy is a retired Parole officer and amateur photographer. A mom of 2, she loves taking nature photos and going on adventures with her kids.

Amanda Brooks

Amanda is a nature enthusiast who loves taking long walks in the woods with her camera and notepad. With her degree in Environmental Studies and English and her background in the arts, she is always looking for creative ways to capture the beauty of nature to inspire its protection. She currently resides in Burlington, Vermont and works as a tree-monger at Gardener’s Supply Company. You can check out more of her work on her Facebook page. 

Check out the photos from last year’s Earth Day photo contest here:

Our 2019 Earth Day Photo Contest Winner!

Volunteer Spotlight: Monitoring Baby Bird Boxes & Counting Shorebirds

We’re excited to put the spotlight on Princeton Hydro Environmental Scientist Emily Bjorhus and her admirable volunteer work.

As an Environmental Scientist, Emily Bjorhus works on a wide range of projects from flood risk management to wetland mitigation to stream restoration. She specializes in wetland and stream ecology and environmental permitting and compliance. Outside of the office, Emily is an active volunteer with Natural Lands and the Delaware Shorebird Project, working to protect natural resources, promote biodiversity, and protect important species. Emily also volunteers at Franklin Delano Roosevelt High School in Brooklyn, NY teaching Environmental Science students about wetlands. We’ve put together a snapshot of Emily’s volunteer activities:

Natural Lands – Force of Nature Volunteer

Natural Lands is a nonprofit organization that saves open space, cares for nature, and connects people to the outdoors in eastern Pennsylvania and southern New Jersey. Founded in the early 1950s, today nearly five million people live within five miles of lands under Natural Lands’ permanent protection.

As a Force of Nature volunteer with Natural Lands, Emily has been monitoring ~20 nest boxes located in meadow and forest edge habitat at Gwynedd Preserve since 2018. From April through mid-August, Emily and another volunteer visit the sites every 5-7 days to monitor the nest boxes for the types of species using the boxes, nest condition, nest materials, number of eggs laid, number of eggs that hatch, and number of chicks that fledge. Chickadees, wrens, blue birds, and tree swallows are the primary species that nest in the boxes Emily monitors.

When asked what she loves most about this volunteer work, Emily said, “I love watching how the birds build their nest week after week, seeing the eggs multiply and tracking the chicks’ growth. I even enjoy dodging dive-bombing tree swallows.”

Delaware Shorebird Project – Data Collection Volunteer

Delaware Shorebird Project is led by DNREC’s Division of Fish & Wildlife in partnership with the U.S. Fish and Wildlife Service, Delaware Museum of Natural History, British Trust for Ornithology and Wash Wader Ringing Group, with the help of experienced and dedicated volunteers like Emily.

The project monitors the health and status of migratory shorebird populations to collect data that can be applied to the conservation of these birds. The research has resulted in better understanding of the ecology of shorebirds migrating through Delaware Bay, management of the horseshoe crab harvest to sustain the shorebirds’ population, and protection of key shorebird habitat.

Emily participated in a 3-day shorebird monitoring initiative, which included counting the number of shorebirds on the beach, re-sighting birds previously marked with leg flags, participating in bird catches, and weighing and measuring birds from the catches. The data collected helps monitor trends in shorebird abundance, migratory routes, condition and other important biological data.

“It’s such a pleasure working with the amazing people that come from all over the world to run and participate in this ambitious study,” said Emily. “The data collected from this program will hopefully aid researchers and policy makers to develop strategies to better protect shorebird habitat in the future.”

Franklin Delano Roosevelt High School Environmental Studies – Guest Speaker

Ms. Hannah Goldstein and her Environmental Science students at Franklin Delano Roosevelt High School in Brooklyn, NY welcome Emily as a volunteer guest speaker to teach all about wetlands. The instruction also includes a hands-on session where students collect soil samples to determine if hydric soils are present and identify surrounding trees using a dichotomous key.

“Science is such an important subject matter for kids to be learning for a variety of reasons. Environmental science education in particular encourages thought patterns, which get kids engaged in real-world environmental protection activities,” said Emily. “I really enjoy working with Ms. Goldstein and her students. I hope my presentation inspires the students to learn more about wetlands and become ambassadors of wetland conservation.”

 

Emily earned her M.S. in Sustainable Engineering at Villanova University and holds a B.S. in Environmental Science from University of Colorado at Boulder. As an Environmental Scientist for Princeton Hydro, she coordinates, leads and assists with state environmental permitting programs and NEPA compliance and documentation, including preparation of Federal and state permit applications, Endangered Species Act 7 consultations, and Federal Energy Regulatory Commission (FERC) environmental review processes. In addition, she conducts a variety of environmental field investigations such as wetland and waterbody delineations.

We’re so proud to have Emily on our team and truly value the work she does inside and outside the office.

Tips to Celebrate Earth Day 2020 While Social Distancing

Earth Day gatherings around the world have been cancelled due to COVID-19, but we can still do our part to honor this important occasion. We’ve put together a list of fun ideas and helpful tips to celebrate Earth Day 2020 safely and responsibly:


Get Outside, Safely

Illustration by New York State Department of Environmental Conservation

Getting outdoors is a great way to celebrate Earth Day, and it can boost your mental and physical health. While remaining mindful about maintaining safe social distancing practices, we can still get outside to take advantage of the spring weather and enjoy the outdoor adventures in our own backyards.

Earth Month Scavenger Hunt from Eco Promotional Products

For more tips on social distancing while visiting parks and natural areas, check out this helpful info from NJ Department of Environmental Protection.


Clean-up Your Neighborhood

Photo: Santiago Mejia, The Chronicle

Although large volunteer clean-up events are postponed due to social distancing guidelines, we can still do our part to pick-up trash and protect our local waterways. Here are a few ideas:

  • When you go outside for an afternoon walk, bring gloves and a garbage bag so you can pick up any trash you see along the way.

  • Check the storm drains in your neighborhood and remove and discard any debris that you find. Get started by reading these DIY tips!


Get Crafting & Birdwatching

Here are some simple DIY crafting ideas to help you pass the time and improve your backyard birdwatching.

  • Orange Feeder: Oranges are a tasty, energizing snack loved by several bird species, especially the Baltimore Oriole. Follow a few simple steps for building an orange feeder, and then sit back and enjoy your backyard bird watching experience!

  • Hummingbird Nectar: Bring more hummingbirds to your backyard this season in a few easy steps! By filling your feeder with this DIY delight, you can watch these beautiful little birds feed and flitter all day.

  • Heart-Shaped Feeder: Show your local songbirds some love with this DIY heart-shaped bird feeder. It makes a charming decoration for your backyard trees.

If you’re interested in taking your birdwatching adventures beyond your backyard, the New York State Department of Environmental Conservation offers a variety of information and online resources to help you do so.


Get your Yard Spring-Ready

Residential homes and neighborhoods can benefit from the implementation of green infrastructure in more ways than many people realize. Planting native flower beds reduces runoff and attracts important pollinators.

  • Reduce Invasives, Plant Natives: Tulips will soon be emerging from the ground, buds blossoming on trees and, unfortunately, invasive plant species will too begin their annual growing cycle. Invasive species create major impacts on ecosystems near and far, but we can all do our part to reduce the spread. To learn more about aquatic invasive species and how to address them, check out our blog.

  • Prepare your Pond for Spring: If you have a pond on your property, check out these six steps for taking your pond out of hibernation mode, sprucing it up for Spring, and ensuring it remains healthy all year long.


Be Water-Wise

Now that we’re all spending more time at home, this is a great opportunity to incorporate better water-conservation practices into our daily lives.

  • Reduce water waste by checking for leaks that have been caused by winter freeze. Check garden hose spigots and sprinklers, and replace valves, washers and other components as necessary.

  • Install a rain barrel and use the captured rainfall to irrigate flower beds. This is another fun and inexpensive way to reduce runoff and save water. You can order a rain barrel online or search online for DIY rain barrel ideas. Remember to cover your barrels to keep mosquitoes at bay.

  • Go here for more water conservation tips.


Let’s Talk Toilets

According to the USEPA, toilets account for more water use than any other water-consuming product in your home. Toilets are estimated to be responsible for upwards of 30% of household water consumption. Additionally, flushing anything besides toilet paper has major negative impacts on the environment.

  • Eliminate toilet leaks: 79% of water lost in the home is through toilet leaks. Often silent, these leaks can waste up to 300 gallons of water per day. Check for leaks using food coloring. Replace the refill valve or flush valve when necessary.

  • Flush Responsibly: NY State Department of Environmental Conservation recently issued an email requesting more responsible flushing habits. As a reminder, disinfectant wipes, diapers, baby wipes, personal hygiene products, and any paper products other than toilet paper should never be flushed! These materials create significant damage to sewer systems, water treatment plants, and septic systems. Learn more.


Go Digital

Earth Day 2020, which also happens to be the 50th anniversary, will now be the first-ever Digital Earth Day. Here are a few ways to celebrate from the safety of your home:

  • Participate in a global Citizen Science effort! Download the Earth Challenge 2020 smart phone app to submit observations of the environment around your home. The data you submit will be validated, and the resulting database—of over one billion data points—will be displayed on a public map for researchers to use.

  • Participate in the Rutger’s Cooperative Extension “Earth Day at Home” free webinar series! Every Monday at 6:30pm EST, starting April 20 through June 29, the live and interactive 1-hour sessions will focus on steps everyone can take to protect the environment. Topics include environmentally friendly lawn care, backyard composting, reducing plastic and food waste, and so much more.

  • Sign-up to be a part of the largest environment mobilization in history: EarthDay.org’s EARTHRISE initiative, which includes social media campaigns, online teach-ins, performances, and more. Find a digital Earth Day Event!

Inspire others to celebrate Earth Day 2020 responsibly by documenting your activities and sharing on social media with hashtags: #EarthDay, #EarthDay2020, #EARTHRISE, and #RecreateLocal. To read about Princeton Hydro’s past Earth Day celebrations, go here.

Free Webinar: Engaging the Media on Clean Water Issues

The American Sustainable Business Council (ASBC) launched the “Clean Water is Good for Business” campaign that gives businesses a strong voice to advocate for water quality protection, reduced nutrient pollution, improved water infrastructure, and policies that make businesses more resilient to floods and droughts. Ultimately, ASBC is hopeful that the campaign helps to shift the dialogue on water issues so that there is a greater balance of business perspectives, including the economic reasons for sensible clean water regulations.

As part of ASBC’s campaign, the organization hosted a series of online training sessions for businesses to help elevate their voice on clean water issues. The most recent webinar, titled “Making the Business Case on Clean Water Issues to the Media,” focused on helping businesses find and approach the right journalists, make the most compelling arguments for policy agenda, enhance credibility and confidence, and much more!

The webinar was lead by Bob Keener, Deputy Director of Public Relations at American Sustainable Business Council; Dana Patterson, Marketing & Communications Manager at Princeton Hydro; Rita Yelda, Outreach & Communications Manager at Coalition for the Delaware River Watershed; and Colton Fagundes, Policy Associate at American Sustainable Business Council.

Dana’s presentation focused on how to build substantive values-based narratives; how to develop engaging media content and effective headlines; how to build relationships with key members of the media; and best practices for media outreach.

If you missed the webinar and are still interested in learning how to build relationships with elected officials and members of the media so you can make your business’ voice heard on the issues and policies that matter, it’s not too late! You can watch the complete webinar on YouTube. And, you can view all of the presentation slides, by clicking here.

For more information about upcoming ASBC events, visit their website. To learn more about Princeton Hydro, go here.

Identifying, Understanding and Addressing Harmful Algae Blooms

Harmful Algae Bloom Visible in Owasco Lake. Photo by: Tim Schneider

Harmful Algae Blooms (HABs) were in the spotlight this summer due to the severe impacts they had on lakes throughout the country. The nation-wide HABs outbreak caused beach closures, restricted access to lake usage, and wide-ranging health advisories.

What exactly are HABs? Why were they so severe this summer? Will this trend continue? Can anything be done to prevent the occurrence or mitigate the impacts?

In this blog, we provide answers to all of those questions, exploring what HABs are, why they occur, why they were particularly prevalent this summer, and what we can do to combat them.

What are HABs?

Simply put, HABs are rapid, large overgrowths of cyanobacteria. Cyanobacteria, also known as blue-green algae, aren’t actually algae, they are prokaryotes, single-celled aquatic organisms that are closely related to bacteria and can photosynthesize like algae. These microorganisms are a natural part of aquatic ecosystems, but, under the right conditions (primarily heavy rains, followed by hot, sunny days), these organisms can rapidly increase to form cyanobacteria blooms, also known as HABs.

HABs can cause significant water quality issues in lakes and ponds, often forming a visible and sometimes odorous scum on the surface of the water. They can produce toxins that are incredibly harmful (even deadly) to humans, animals, and aquatic organisms. HABs also negatively impact economic health, especially for communities dependent on the income of jobs and tourism generated through their local lakes and waterways.

What causes HABs?

HABs are caused by a complex set of conditions, and many questions remain about exactly why they occur and how to predict their timing, duration, and toxicity. Primarily, HABs are caused by warmer temperatures and stormwater run-off pollutants, including fertilizers with phosphates.

NY Times article, featuring Princeton Hydro, looks at how climate change affects lakes nationwide, using NJ as an example. Photo by: Rick Loomis, NY Times.HABs are induced by an overabundance of nutrients in the water. The two most common nutrients are fixed nitrogen (nitrates and ammonia) and phosphorus. Discharges from wastewater treatment plants, runoff from agricultural operations, excessive fertilizer use in urban/suburban areas, and stormwater runoff can carry nitrogen and phosphorus into waterways and promote the growth of cyanobacteria.

Climate change is also a factor in HAB outbreaks, which typically occur when there are heavy rains followed by high temperatures and sunshine. Climate change is leading to more frequent, more intense rainstorms that drive run-off pollutants into waterways, coupled with more hot days to warm the water. These are the ideal conditions for HABs, which in recent years have appeared in more places, earlier in the summer.

With climate change and increasing nutrient pollution causing HABs to occur more often and in locations not previously affected, it’s important for us to learn as much as we can about HABs so that we can reduce their harmful effects.

What Can I Do to Prevent HABs?

Signs on the closed beach at Hopatcong State Park warn residents of the Harmful Algae Bloom at Lake Hopatcong on July 2019, in Landing, NJ. (Photo by: Danielle Parhizkaran of NorthJersey.comThe number one thing individuals can do to protect their waterbodies and prevent HABs is to reduce phosphorous use and reduce nutrient loads to waters.

According to Dr. Fred Lubnow, Director of Aquatic Programs for Princeton Hydro, “Managing loads of phosphorous in watersheds is even more important as the East Coast becomes increasingly warmer and wetter thanks to climate change. Climate change will likely need to be dealt with on a national and international scale. But local communities, groups, and individuals can have a real impact in reducing phosphorous levels in local waters.”

Here are a few steps you can take to improve water quality in your community lakes:

Controlling stormwater runoff is another critical factor in improving water quality and reducing HABs. There are a number of low-cost green infrastructure techniques that can be implemented on an individual and community-wide scale. You can read more about green infrastructure stormwater management techniques in our recent blog.

In a recent Op/Ed published on NJ.com, Princeton Hydro President Geoff Goll lists four things that residents, businesses, and local governments should do to prevent another HABs outbreak next summer:

  1. Improve aging “gray” infrastructure
  2. Invest in “green” stormwater infrastructure
  3. Implement regional/watershed-based planning
  4. Pass the Water Quality Protection and Jobs Creation Act

“By making the necessary investments, we can simultaneously create jobs, reduce flood impacts, improve fisheries, maintain or increase lakefront property values, improve water quality and preserve our water-based tourism. The time to act is literally now,” said Geoff. Go here, to read the full article.

HABs Management in Action through Floating Wetland Islands:

Nitrogen and phosphorus are utilized by plants, which means they uptake these nutrients to sustain growth. We see this naturally occurring in wetland ecosystems where wetlands act as a natural water filtration system and can actually thrive from nutrients flowing in from external sources.

This process is replicated in floating wetland islands (FWIs), where you typically have a constructed floating mat with vegetation planted directly into the material. The plants then grow on the island, rooting through the floating mat.

This illustration, created by Staff Scientist Ivy Babson, conveys the functionality of a Floating Wetland Island

This illustration, created by Staff Scientist Ivy Babson, conveys the functionality of a Floating Wetland Island

Not only do FWIs assimilate and remove excess nitrogen and phosphorus out of the water, they also provide habitat for fish and other aquatic organisms; help mitigate wave and wind erosion impacts; provide an aesthetic element; and can be part of a holistic lake/pond management strategy. Because of this, FWIs are being utilized to improve water quality and control HABs in lakes and ponds throughout the country. Princeton Hydro has designed and implemented numerous FWIs in waterbodies large and small. Go here to learn how they’re being used in Harveys Lake.

 

Recognizing and monitoring the changes that are taking place in our local waterways brings the problems of climate change, stormwater pollution and the resulting water quality issues closer to home, which can help raise awareness, inspire environmentally-minded action and promote positive, noticeable change.

If you spot what you believe to be a harmful algae bloom in your community lake, contact your local lake association right away. They, along with their lake management team, can assess the situation and determine what further actions need to be taken.

For more information about harmful algae blooms and water quality management, go here: http://bit.ly/pondlake.

Special thanks to Princeton Hydro Staff Scientist Ivy Babson for her contributions to this blog.

REGISTER: Green Infrastructure Stormwater Management One-Day Course

REGISTRATION IS STILL OPEN FOR MONTCLAIR STATE UNIVERSITY’S GREEN INFRASTRUCTURE STORMWATER MANAGEMENT ONE-DAY CONTINUING EDUCATION COURSE BEING HELD ON SEPTEMBER 20, 2019 FROM 8 AM – 4 PM

Are you a consultant, planner, municipal representative, community leader, or project manager seeking to learn more about Green Stormwater Infrastructure & Management Techniques? This one-day course is for YOU!

Green infrastructure techniques have increasingly become the “go to” strategy to address flooding, water quality, and environmental impacts caused by stormwater runoff. Whether it be rain gardens or regional bioretention basins, infiltration basins or other large-scale bio engineered BMPs, green infrastructure is being implemented everywhere from suburban subdivisions to urban redevelopment sites. Unfortunately, while growing popular, these techniques are often misapplied, improperly constructed, or inadequately maintained.

This innovative one-day class focuses on the proper design and implementation of green infrastructure BMPs, as well as their special maintenance requirements. The course curriculum includes interactive presentations, case studies and project examples.

This year’s course will cover the following topics and more:

  • The Application and Advantages of Green Infrastructure Stormwater Management Techniques
  • Design and Construction of Infiltration Basins
  • Data Collection Needs: Soil, Geotechnical, and Groundwater Hydrology Data
    Design and Construction of Gravel Wetland Systems
  • Rain Garden Design and Application
  • Green Infrastructure Stormwater Options and Alternative Capping Techniques for Remediation Sites

Dr. Stephen Souza, Princeton Hydro Co-Founder and President of Clean Waters Consulting, LLC, is the faculty coordinator for the course, which also features a lecture by Princeton Hydro’s Green Infrastructure Practice Area Leader Dr. Clay Emerson, PE, CFM.

Course participants will also receive professional credits, including:

  • New Jersey LSRP CECs: 7 Technical CECs (NJ SRPLB Course # 2015-065);
  • New Jersey Professional Engineers: 7 CPCs;
  • New Jersey Board of Architects: 7 hours of CECs;
  • Certified Floodplain Managers: 6.5 CECs; and
  • NJ Public Health Continuing Education Contact Hours: 7 CEs.

Princeton Hydro is proud to partner with Montclair State University and take part in this valuable continuing professional education course. We hope to see you there!

Learn More & Register Today

Washington Post’s Climate Story Features Princeton Hydro

Photo credit: The Washington Post

Did you know that New Jersey is one of the fastest-warming states in the nation? Not only that, did you know the average temperature increase in the state is double the average of the rest of the Lower 48 states?

In a recent article, the Washington Post uncovers quite startling findings from analysis of more than a century of National Oceanic and Atmospheric Administration temperature data across the Lower 48 states and 3,107 counties. The article takes a specific look at the impacts climate change has had on Lake Hopatcong.

Princeton Hydro has been working with Lake Hopatcong for 30+ years, restoring the lake, managing the watershed, reducing pollutant loading, and addressing invasive aquatic plants and nuisance algae bloomsLake Hopatcong has one of the longest, continuous, long-term ecological databases in New Jersey; 30+ years of consistently collected water quality data.

Dr. Fred Lubnow, Director of Aquatic Programs, and Katie Walston, Senior Scientist, are featured in the Washington Post article. Here’s an excerpt:

On a cool but sunny day in May, Fred Lubnow, director of aquatic programs at Princeton Hydro, and Katie Walston, a senior scientist there, pulled up their anchor in Lake Hopatcong to find it covered with aquatic weeds. The culprit? Fertilizer runoff combined with winters too warm to kill them off.

“The plants start growing earlier and linger around longer, as well,” Lubnow said. The thick ice blocked sunlight from nurturing the weeds. But “in some of these shallow areas, as early as February, we’re looking through the ice seeing the plants growing.”

By summer, the weeds become a nuisance, forcing the state government to “harvest” them with large paddles and toss them onto a conveyor belt, then onto barges. Some years, funding has been hard to get, delaying harvesting and angering homeowners.

“If this area is not harvested, you can’t get a boat through it,” Lubnow says. Swimming isn’t possible, either. Fishing becomes difficult.

Get the full Washington Post story here!

If you’d like to read more about climate change, check out our recent blog:

Four Ways Climate Change Can Affect Your Lake

 

 

 

Four Ways Climate Change Can Affect Your Lake

The Local Effects of Climate Change Observed Through our Community Lakes

Climate change is an enormous concept that can be hard to wrap your head around. It comes in the form of melting ice caps, stronger storms, and more extreme seasonal temperatures (IPCC, 2018). If you’re an avid angler, photographer, swimmer, boater, or nature enthusiast, it’s likely that because of climate change you’ll bear witness to astonishing shifts in nature throughout the greater portion of your lifetime. This is especially true with respect to lakes.

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Lakes are living laboratories through which we can observe the local effects of climate change in our own communities. Lake ecosystems are defined by a combination of various abiotic and biotic factors. Changes in hydrology, water chemistry, biology, or physical properties of a lake can have cascading consequences that may rapidly alter the overall properties of a lake and surrounding ecosystem. Most of the time the results are negative and the impacts severe.

“Managing loads of phosphorous in watersheds is even more important as the East Coast becomes increasingly warmer and wetter thanks to climate change,” said Dr. Fred Lubnow, Director of Aquatics in a recent NJ.com interview. “Climate change will likely need to be dealt with on a national and international scale. But local communities, groups, and individuals can have a real impact in reducing phosphorous levels in local waters.”

Recognizing and monitoring the changes that are taking place locally brings the problems of climate change closer to home, which can help raise awareness and inspire environmentally-minded action.

We put together a list of four inter-related, climate change induced environmental impacts that can affect lakes and lake communities:

1. Higher Temperatures = Shifts in Flora and Fauna Populations

The survival of many lake organisms is dependent on the existence of set temperature ranges and ample oxygen levels. The amount of dissolved oxygen (DO) present in a lake is a result of oxygen diffusion from the atmosphere and its production by algae and aquatic plants via photosynthesis. An inverse relationship exists between water temperature and DO concentrations. Due to the physical properties of water, warmer water holds less DO than cooler water.

This is not good news for many flora and fauna, such as fish that can only survive and reproduce in waters of specific temperatures and DO levels. Lower oxygen levels can reduce their ability to feed, spawn and survive. Populations of cold water fish, such as brown trout and salmon, will be jeopardized by climate change (Kernan, 2015).

358-001-carp-from-churchvilleAlso, consider the effects of changing DO levels on fish that can tolerate these challenging conditions. They will thrive where others struggle, taking advantage of their superior fitness by expanding their area of colonization, increasing population size, and/or becoming a more dominant species in the ecosystem. A big fish in a little pond, you might say. Carp is a common example of a thermo-tolerant fish that can quickly colonize and dominate a lake’s fishery, in the process causing tremendous ecological impact (Kernan, 2010).

2. Less Water Availability = Increased Salinity

Just as fish and other aquatic organisms require specific ranges of temperature and dissolved oxygen to exist, they must also live in waters of specific salinity. Droughts are occurring worldwide in greater frequency and intensity. The lack of rain reduces inflow and higher temperatures promote increased evaporation. Diminishing inflow and dropping lake levels are affecting some lakes by concentrating dissolved minerals and increasing their salinity.

Studies of zooplankton, crustaceans and benthic insects have provided evidence of the consequences of elevated salinity levels on organismal health, reproduction and mortality (Hall and Burns, 2002; Herbst, 2013; Schallenberg et al., 2003). While salinity is not directly related to the fitness or survival rate of all aquatic organisms, an increase in salinity does tend to be stressful for many.

3. Nutrient Concentrations = Increased Frequency of Harmful Algal Blooms

Phosphorus is a major nutrient in determining lake health. Too little phosphorus can restrict biological growth, whereas an excess can promote unbounded proliferation of algae and aquatic plants.

before_strawbridgelake2If lake or pond water becomes anoxic at the sediment-water interface (meaning the water has very low or completely zero DO), phosphorus will be released from the sediment. Also some invasive plant species can actually “pump” phosphorus from the sediments and release this excess into the water column (termed luxurious uptake). This internally released and recycled sedimentary phosphorus can greatly influence lake productivity and increase the frequency, magnitude and duration of algae blooms. Rising water temperatures, declining DO and the proliferation of invasive plants are all outcomes of climate change and can lead to increases in a lake’s phosphorus concentrations and the subsequent growth and development of algae and aquatic plants.

Rising water temperatures significantly facilitate and support the development of cyanobacteria (bluegreen algae) blooms. These blooms are also fueled by increasing internal and external phosphorus loading. At very high densities, cyanobacteria may attain harmful algae bloom (HAB) proportions. Elevated concentrations of cyanotoxins may then be produced, and these compounds seriously impact the health of humans, pets and livestock.

rain-garden-imagePhosphorus loading in our local waterways also comes from nonpoint sources, especially stormwater runoff. Climate change is recognized to increase the frequency and magnitude of storm events. Larger storms intensify the mobilization and transport of pollutants from the watershed’s surrounding lakes, thus leading to an increase in nonpoint source loading. Additionally, larger storms cause erosion and instability of streams, again adding to the influx of more phosphorus to our lakes. Shifts in our regular behaviors with regards to fertilizer usage, gardening practices and community clean-ups, as well as the implementation of green infrastructure stormwater management measures can help decrease storm-related phosphorus loading and lessen the occurrence of HABs.

4. Cumulative Effects = Invasive Species

A lake ecosystem stressed by agents such as disturbance or eutrophication can be even more susceptible to invasive species colonization, a concept coined “invasibility” (Kernan, 2015).

For example, imagine that cold water fish species A has experienced a 50% population decrease as a result of warming water temperatures over ten years. Consequently, the fish’s main prey, species B, has also undergone rapid changes in its population structure. Inversely, it has boomed without its major predator to keep it in check. Following this pattern, the next species level down – species B’s prey, species C – has decreased in population due to intense predation by species B, and so on. Although the ecosystem can potentially achieve equilibrium, it remains in a very unstable and ecologically stressful state for a prolonged period of time. This leads to major changes in the biotic assemblage of the lake and trickle-down changes that affect its recreational use, water quality and aesthetics.

• • •

Although your favorite lake may not experience all or some of these challenges, it is crucial to be aware of the many ways that climate change impacts the Earth. We can’t foresee exactly how much will change, but we can prepare ourselves to adapt to and aid our planet. How to start? Get directly involved in the management of your lake and pond. Decrease nutrient loading and conserve water. Act locally, but think globally. Get out and spread enthusiasm for appreciating and protecting lake ecosystems. Also, check out these tips for improving your lake’s water quality.


References

  1. IPCC. “Summary for Policymakers. “Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty.” World Meteorological Organization, Geneva, Switzerland, 32 pp. 2018.
  2. Hall, Catherine J., and Carolyn W. Burns. “Mortality and Growth Responses of Daphnia Carinata to Increases in Temperature and Salinity.” Freshwater Biology 47.3 (2002): 451-58. Wiley. Web. 17 Oct. 2016.
  3. Herbst, David B. “Defining Salinity Limits on the Survival and Growth of Benthic Insects for the Conservation Management of Saline Walker Lake, Nevada, USA.” Journal of Insect Conservation 17.5 (2013): 877-83. 23 Apr. 2013. Web. 17 Oct. 2016.
  4. Kernan, M. “Climate Change and the Impact of Invasive Species on Aquatic Ecosystems.” Aquatic Ecosystem Health & Management (2015): 321-33. Taylor & Francis Online. Web. 17 Oct. 2016.
  5. Kernan, M. R., R. W. Battarbee, and Brian Moss. “Interaction of Climate Change and Eutrophication.” Climate Change Impacts on Freshwater Ecosystems. 1st ed. Chichester, West Sussex, UK: Wiley-Blackwell, 2010. 119-51. ResearchGate. Web. 17 Oct. 2016.
  6. Schallenberg, Marc, Catherine J. Hall, and Carolyn W. Burns. “Consequences of Climate-induced Salinity Increases on Zooplankton Abundance and Diversity in Coastal Lakes”Marine Ecology Progress Series 251 (2003): 181-89. Inter-Research Science Center. Inter-Research. Web.