Cyanobacteria

Cyanobacteria (also known as “blue-green algae”) are a natural part of any aquatic ecosystem and normal amounts are not problematic. However, excessive nutrients combined with warming temperatures create ideal conditions for cyanobacteria to multiply rapidly and create toxic algae blooms. The excessive nutrients, principally phosphates, come from septic systems (urine), lawn fertilizer, household detergents and grass clippings that drain into the pond, herring run and ground water. Algae blooms are increasingly common in ponds across the Cape and can pose a serious environmental and public health concern. When a body of water is experiencing a Cyanobacteria bloom, public health officials post advisories to warn the public of potential health threats to pets and swimmers.

Cyanobacteria blooms in high concentrations can appear as greenish scum on the surface of the pond generally around the edges

Cyanobacteria blooms in high concentrations can appear as greenish scum on the surface of the pond generally around the edges

The Town of Barnstable is monitoring about 20 ponds including Long Pond. Last summer was the eighth consecutive year that a public health warning was issued for Long Pond due to higher than normal cyanobacteria. The amount posed a low to moderate risk to the general public but a higher risk to babies, small children and pets who might ingest the water.

To address the excess phosphates from septic systems (as well as other issues), the Town of Barnstable has developed a Comprehensive Wastewater Management Plan and, fortunately for us, the areas around Long Pond and Lake Wequaquet are included in Phase 1 of the sewer expansion. Phase 1, however, is expected to take up to 10 years to complete so we need to continue to do our part to reduce contamination by properly maintaining our septic systems, using only non-phosphate fertilizers and using eco-friendly detergents and soaps.

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