Algae Bloom in Upper Sarananc Lake A lake-wide algae bloom that began last week on Upper Saranac Lake is varying in degrees of intensity depending on location. Some of the thicker, green colored water has been along the west shore of the North Basin. Likely there were a variety of factors contributing to the bloom; lake turn over, warmer temperature, sunny and calm days. When environmental conditions are just right, algae can grow very quickly in number.

Samples of the Upper Lakes algae bloom were taken and analyzed by The Adirondack Watershed Institute at Paul Smith’s College (AWI). AWI concluded that the bloom, a form of blue–green algae is an Anabaena species. This species is buoyant and will float to the surface, where they form scum layers or floating mats. Although the bloom is thick in some areas, overall it is a light to moderate in most other areas of the lake.

“this bloom is not the direct result of point source nutrients. Rather, it is probably the result of a combination of limnological events that have resulted in an increase buoyancy of these organisms. Anabaena, like many other cyanobacteria, can control their position in the water column to achieve optimal growth conditions (light, nutrients, inorganic carbon etc.). Excessive buoyancy has been shown to result from deficiencies in light and inorganic carbon that occurs in late autumn in stratified waters. When they become excessively buoyant, a surface scum appears”.

Many residents were quick to question the practices of the Fish Hatchery. Although the Hatchery’s past practices from the 1980s may affect the lake for years to come, through collaboration of the DEC and the Upper Saranac Foundation, the Hatchery has less phosphorous discharge than ever before. In fact, the Upper Lake is not alone when it comes to this recent outbreak of algae blooms; the St. Regis Lakes, Barnham Pond, Middle and Lower Saranac Lakes are all experiencing similar blooms.

Unfortunately, there are no quick fixes to algae blooms. All lakes have their own unique chemistries and the Upper Saranac is no exception. One aspect of our lake’s chemistry is a relatively high inherent level of Phosphorus and is a major causal agent in algae blooms. That Phosphorus is part of the nature of our lake and its biological makeup, means we are continually close to pushing the limits of reoccurring blooms. Blooms probably have occurred before there were even inhabitants to the lake. Now humans influence the frequency of these blooms. Our actions have the potential to alter the balance between having a bloom or not. We do know that properly working septic systems and waste water contribute to Phosphorus levels. We also know that minimizing erosion, controlling storm water runoff, not using fertilizers, and maintaining a shoreline vegetative buffer, all help to limit our impact and preventing algae blooms.

Concerns associated with blue-green algae include discolored water, reduced light penetration, taste and odor problems, dissolved oxygen depletions, and toxin production. When a blue-green algae bloom dies off, the blue-green algae cells sink and are broken down by microbes. This breakdown process requires oxygen and can create a biological oxygen demand. Increases in biological oxygen demand result in decreases in oxygen concentration in the water, and this can adversely affect fish and other aquatic life, and can even result in fish kills. Because the lake is often near the threshold of blooms it is important that we as residents do not tip the scales in favor of a bloom. If you have any further questions or concerns regarding this topic or others associated with water quality, please feel free to contact me at

By Guy Middleton, Lake Manager