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The Environmental Impacts of an Algae Bloom on Lake Hopatcong, New Jersey

As told by Veronica Carrion, Kailey Pasquariello, Matthew Sinchi
Lake Hopatcong, New Jersey

Story Narrative:

A man with white hair, glasses, and a blue winter jacket stands outside in a parking lot and chats with an interviewer.

Students at the Environmental Science Academy at Jefferson Township High School in New Jersey worked with the Lake Hopatcong Foundation to produce this story about a historic 2019 algae bloom in the state's largest lake. This project is part of the Stories: Yes student storytelling initiative with Museum on Main Street. This episode is PART 1 of 3.

Speaker 1 (00:00): Many communities have a main street, the center of town that marks what might be the busiest, oldest or most important part of that town. But what if that main street wasn't a street at all, but a lake? Welcome to Lake Hopatcong, New Jersey, the state's largest lake. For the four towns around the lake, Jefferson, Mount Arlington, Roxbury and Hopatcong, this lake is the hub for business, tourism and ecology. But in the summer of 2019, the lake was struck with a harmful algae bloom known as a HAB. This is a story best told while looking from three different perspectives. This is part one of three where we'll examine the environmental aspect of the algae bloom.

Fred Lubnow (00:38): In a freshwater system most of your HABs, most of your harmful algal blooms are cyanobacteria, which are technically bacteria that pretend to be plants. They're bacteria that photosynthesize. We call them algae, but technically they're cyanobacteria.

Speaker 1 (00:55): HABs grew across the entirety of Lake Hopatcong, making the water in some coves look like a goopy pea soup.

Robert DeFillippo (01:01): What happened this time was sort of a, no pun intended, but sort of the perfect storm. We had a lot of rain. Phosphates from lawns and fertilizers washed into the lake as it always does, and then it was very warm. All of those contributed to the algae bloom.

Fred Lubnow (01:25): Now, typically to get a really nasty HAB bloom, there are three things that the cyanobacteria like. First, they like warmer temperatures. We've seen that like on Lake Hopatcong we have a statistically significant increase in the surface water temperatures in the summer months. Now, the thing about cyanobacteria is they can fix their own nitrogen from the atmosphere. So unlike other algae that need a lot of nitrogen, they don't need a lot. They can pull it from the atmosphere, but to do that, they need a lot of phosphorus, and that's why when you see more phosphorus, you'll see more of the cyanobacteria.

Speaker 1 (02:00): Phosphorus can be found mostly in fertilizer or in fecal waste.

Ron Smith (02:06): It starts out when they fertilize their lawns, especially the people on the lakefront. There's phosphate in the fertilizer. Then it rains and that washes into the lake. Also, even back from the lake across when people fertilize their lawns, it gets into the storm sewers. All those storm sewers enter into the lake.

Speaker 1 (02:25): Once the algae is given the proper conditions to grow, it can get out of control, causing a myriad of issues.

Katrina Angarone (02:31): As I said before, a cell will produce toxins at any time, and the toxins are associated with even more serious health effects. They're not just an inconvenience. They can be quite dangerous, particularly for children who are more prone to accidentally ingesting water when swimming and playing.

Fred Lubnow (02:52): Some people have allergic reactions. You can feel nauseous, dizzy. This is if you have really high concentrations.

Speaker 1 (03:00): Health concerns also shift to the animals and pets around the lake.

Fred Lubnow (03:04): So if a dog is playing on a beach and they're hot, they're just going to jump into the water to cool down. Even if they don't drink that water, when they come out a lot of times they're licking their fur, and dogs are more susceptible to these cyanotoxins than people.

Speaker 1 (03:18): As the algae bloom grew, experts turned their attention to figuring out the best way to deal with the HAB.

Katrina Angarone (03:23): We put together an expert harmful algal bloom panel, which is filled with state and local experts as well as some out-of-state folks who will help us try to craft some guidance. We are meeting regularly with local officials and generally just trying to partner with them and make sure that they're educated about the threats and the underlying causes.

Speaker 1 (03:48): The DEP was working hard with local governments to find solutions and preventative measures.

Fred Lubnow (03:54): We've been working with the commission since their inception. We helped them develop, number one, a management plan for the watershed. We had one, but it was 12 years old and needed to be updated. After 2019, the commission was awarded a $500,000 to implement a wide variety of projects throughout the lake and watershed to evaluate how we can deal with these HABs.

Katrina Angarone (04:17): So we spent millions of dollars giving grants to locals who are plagued with this issue. We continue to promulgate rules that are aimed at reducing nutrients through our stormwater regulations, Phoslock, which is a substance that sort of locks out that excess nutrient of phosphorus and some aeration among some other projects, longer term ones that we are funding as well.

Michael Stanzilis (04:44): The results are spectacular with aeration so we're going to do an aeration system here as well. That really helps to circulate the water and keeps that algae from growing and getting out of control.

Speaker 1 (04:55): Even though the 2019 HAB was the worst that Lake Hopatcong has faced, experts don't think that it'll be the last.

Katrina Angarone (05:02): With a warming climate, we are really expecting to see more of these and see them persist. In fact, we've been seeing them persist over the winter, which is concerning to be sure.

Speaker 1 (05:12): In order to keep another HAB from shutting the lake down, residents are encouraged to play their part too.

Katrina Angarone (05:18): There's no one-size-fits-all approach, but putting your own rain garden in to slow the water down and give the nutrients some time to settle, fertilizing your lawn responsibly only after having it tested and making sure that you need to do that. Maintaining your septic system is a really important management technique to make sure that it gets pumped out regularly. Something as small as picking up after your pets is important.

Fred Lubnow (05:47): So if you live in the watershed, anything you can do on your property to minimize your particular load goes a long way. That doesn't sound like a lot, but one pound of phosphorus can generate up to 1100 pounds of that green cotton candy you see in a lake or pond.

Ron Smith (06:01): What they want to do is get people to build a little garden, a buffer just before their property enters the water back about four foot to make plants. That'll take the water and filter it before it gets into the lake.

Fred Lubnow (06:14): Some of the homes are on septic. So if they pump out their septic system once every three to five years, that alone will reduce their septic load of phosphorus by 20 to 30%.

Speaker 1 (06:26): With the proper treatments and attention, the HAB can be kept under control to ensure that the events of 2019 don't repeat themselves.

Marty Kane (06:34): The Department of Environmental Protection has moved out with a very broad-based program to try to confront algal blooms. A lot of it has been funding to do demonstration projects and demonstration projects not just to fix the problem if it happens, but try to prevent it from ever happening.

Speaker 1 (06:54): To learn more, visit the New Jersey Department of Environmental Protect website at

Asset ID: 2022.11.01
Themes: Algae bloom, pollution, nitrates, phosphorus, pesticides, tourism, boating, family, working together, community action, recreation, hiking, fishing, fear, education, rain gardens, native plants
Date recorded: 2021
Length of recording: 07:02 m
File Type: Video
Related traveling exhibition: Water/Ways
Sponsor or affiliated organization: Lake Hopatcong Foundation and the Academy for Environmental Science at Jefferson Township High School, New Jersey
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