If you hoard summer memories for winter’s dark days, you’ll doubtless want to quickly skip over the marked occurrence in 2019 of harmful algal blooms in the state’s waters; algal toxins fouled at least a dozen lakes, including Lake Hopatcong, the state’s largest and most important recreational lake — which the state Department of Environmental Protection closed to swimmers, boaters and others on June 27 because of a massive bloom.
The DEP points out that harmful algal blooms, also known as HABs, are not true algal blooms. Rather, they are caused by naturally occurring cyanobacteria that can reproduce to unhealthful levels under certain conditions, including sunlight, nutrients from sources such as fertilizers and improperly operating septic systems, warm weather and stagnant water. They frequently form dense mats, resembling pea soup or spilled paint. Exposure to them can result in rashes, allergy-like reactions, flu-like symptoms, gastroenteritis, respiratory irritation and eye irritation. Exposure to a bloom that is actively producing cyanotoxins may result in more serious health effects, including liver toxicity and neurological effects.
Out of a suspected 70 blooms reported in 2019, 39 were confirmed. These resulted in health and water-contact advisories, closures of bathing beaches and, in some cases, impacts on tourism-related businesses.