In a recent blog post, Dr. Fred Lubnow, Princeton Hydro’s Senior Technical Director of Ecological Services, urged community members to closely monitor their lakes for harmful algal blooms (HABs). He highlighted that an unusually mild winter, increased precipitation, and anticipated high summer temperatures could create conditions similar to those in 2019, a year noted for widespread harmful algal blooms on Lake Hopatcong and numerous other lakes.

You can read the full blog post: Preparing for Potential Harmful Algal Blooms: An Urgent Call to Action for NJ’s Lakes and Reservoirs.

HABs are caused by an overgrowth of naturally occurring cyanobacteria. High temperatures and excess nutrient levels can lead to a proliferation or bloom, which poses risks to human health, wildlife, aquatic organisms, ecological stability, and even local economies. These blooms are often characterized by dense green mats that resemble pea soup or spilled paint on the water's surface.

Avoid It and Report It

If you observe a suspected HAB, avoid touching the water and protect your pets. You can report it using this form or call the NJDEP Hotline at 1-877-WARNDEP (927-6337).

Testing Results

You can also view NJDEP algal bloom testing results by location here. Please note that all results remain on the map for the year, so check the date of the sample for current information.

Alert Index

A color-coded health alert index is used to guide the public on suitable recreational activities in water bodies affected by harmful algal blooms.

For additional information on HABs, visit the NJDEP HAB resource page.

Community awareness and proactive monitoring are essential. By staying informed and vigilant, we can help protect our lake and community from the harmful effects of algal blooms.