HAB’s (Dr. Souza article)

Open Letter to the Editor:

More nutrients are not always a good thing: The case for a Harmful Algal Bacteria Standard in NJ

Why are some of New Jersey’s most popular public lakes suddenly off limits at the peak of our summer swimming season? More often than not the reason for the closing is a harmful algae bloom (HAB).  These blooms, often, but not always, characterized by surface scums that are bright green to fuchsia in color, are the result of the accumulation of cyanobacteria commonly referred to as blue-green algae.  Intense blooms can release elevated concentrations of cyanotoxins into the water, which can cause mild to serious health issues for humans, pets, or livestock drinking or coming in contact with the water. Under extreme conditions, the results can be fatal, but luckily those instances are rare.

HABs are not a new phenomenon in New Jersey; drinking water reservoirs and recreational lake managers have been battling HABs for decades.  However, the science behind what causes these blooms and how to detect and implement proper actions to lessen the severity of a bloom have advanced over the past decade.  Bottom line is that HABs are largely the result of too many nutrients (phosphorus and nitrogen).  Although both phosphorus and nitrogen are needed to support a healthy lake ecosystem, too much nutrients are not always a good thing.

Here’s a quick science lesson:  In freshwater aquatic environments phosphorus is the “limiting nutrient,” meaning it is in short supply and high demand.  The more phosphorus entering the environment equals more productivity which results in more algae.  It doesn’t take much phosphorus to stimulate a bloom, as little as 0.03 mg/L can be enough. And, when the conditions are just right (e.g., high summer water temperatures and still water conditions), the algal community often becomes dominated by cyanobacteria.

So, where does this phosphorus come from?  The vast majority is transported by stormwater runoff that mobilizes and transports the nutrients originating from pet waste, fertilizers, goose droppings, septic systems, every paved surface.  Long-term, successful HAB control therefore has to focus on phosphorus management, with prioritization given to controlling the amount and quality of stormwater entering our lakes, ponds and reservoirs.

While the NJ Department of Environmental Protection (NJDEP) has become increasingly attune to HABs, and has taken steps to protect the public from the potential health issues associated with these blooms, they must go one step further.  To protect the health of recreational lake users, we must put into action a definitive protocol for sampling HABs and an actual water quality standard that can be used to define a HAB and let the public know it’s not safe to drink or recreate in the affected lake.  We do the same thing now for the testing of E. coli and/or fecal coliform to determine if pathogen levels are too high for safe swimming. A definitive sampling protocol and legislation supported water quality standard takes the uncertainty out of identifying a HAB and communicating risks to the public.  This would also allow for ongoing monitoring and a unified method for issuing warnings and closures in a timely manner.  Conversely it would also provide an objective basis for establishing when a HAB has diminished and when it’s safe to re-open a lake to contact recreation.    

In 2015 and 2016, the U.S. Environmental Protection Agency published user guidelines for cyanotoxins measured in both drinking water and recreational water. Similar to NJDEP, the New York State Department of Environmental Conservation (NYSDEC) tracks HABs and issues warnings and closures.  However, NYSDEC follows a well-defined protocol and has promulgated actual cyanotoxin criteria that are used to determine when the public is at risk.  It’s time for New Jersey to follow suit.  New York’s protocol utilizes a combination of visual and analytical data to define the occurrence of a HAB. A visual assessment of a possible bloom (e.g., a dense surface scum) triggers a bloom warning.  Sampling is then conducted to support a three-tier bloom status notification; Suspicious Bloom (visual evidence of a possible HAB), Confirmed Bloom (data supports the bloom is due to cyanobacteria present at elevated densities/cell counts, microcystin exceeds4 µg/L), and Confirmed with High Toxins Bloom (microcystin exceeds 20 µg/L).

In 2018, recognizing the severity of HABs and its impacts to New York’s drinking water and recreational waterbodies, New York’s Governor Cuomo appropriated $65 million for HAB management. This funding increased statewide monitoring of HABs as well as the implementation of measures to control the causes of HABs and reduce the severity of reported HABs. Why hasn’t the New Jersey legislature taken this public health risk as seriously as New York?

In the short-term, NJDEP must work towards putting into place a definitive HABs sampling protocol and uniform reporting procedure, and ultimately adopt a numeric based water quality standard.  This will better help NJDEP identify and define a HAB and communicate the risks to the public health. Equally important, over the long-term, we need to be doing a better job managing the primary case of HABs by decreasing stormwater driven phosphorus and nitrogen loading and decreasing the volume of stormwater runoff entering our lakes.  This means better compliance from government agencies with existing municipal separate storm sewer (MS4) regulations, implementation of more green infrastructure stormwater management techniques, and more from individuals to pick up after their dog, forego feeding the geese, and reduce the amount of fertilizer applied to lawns.  Furthermore, these short-term and long-term strategies must be backed by dedicated funding to protect and manage of our treasured lakes, ponds and reservoirs. These waterbodies provide valuable year-round recreation for boaters, kayakers, and swimmers as well as clean drinking water for millions of New Jerseyans.   It is ultimately up to us to lessen the occurrence of HABs, increase our understanding of the problem, and lessen health risks to the public.  This is practical and achievable.  So what are we waiting for?

Dr. Stephen J. Souza

Owner, Clean Waters Consulting, LLC

Ringoes, New Jersey

Dr. Stephen Souza is the owner of Clean Waters Consulting.  Dr. Souza is also the Founder of Princeton Hydro, LLC and served up until his retirement as President.  The focus of this career has been the protection and enhancement of aquatic ecosystems, in particular the management and restoration of lakes, ponds and reservoirs.  Dr. Souza is a past president of the Pennsylvania Lake Management Society and the North American Lake Management Society.  He was the 2012 recipient of the NJ-AWRA Peter J. Homack Award, the 2017 NALMS Lake Management Success Story award recipient and the 2018 New York State Federation of Lakes Lake Tear of the Clouds Life Time Achievement Award.  He is actively involved in the New Jersey Coalition of Lakes Association and teaches continuing education courses for Rutgers in lake and pond management and restoration.