The North Carolina Department of Environmental Quality Division of Water Resources (DWR) advises the public to avoid contact with green or blue water in a canal near Bay Tree Lake in Bladen County due to an algal bloom that has lingered in the area since Oct. 27.
The bloom has been observed within the eastern end of the canal between Bay Tree Lake and Horsepen Bay in Bladen County. Since algal blooms tend to move due to wind and wave action, an investigation by DWR staff determined the bloom was concentrated at the end of the canal by the wind.
Based on testing of samples collected from this concentrated area, DWR determined the bloom is dominated by Microcystis, a single-celled organism that belongs to the algal group cyanobacteria, also known as blue-green algae. Cyanobacteria blooms usually appear bright green, but when a bloom starts to decay, the color can change to a milky blue. Decaying algae may produce a strong, foul odor that can impact a large area.
Microcystis can produce microcystin, an algal toxin that may cause adverse health effects in humans and pets. An analytical test detected microcystin in this bloom at 1,700 parts per billion, exceeding public health advisory levels. Results have been reported on DWR’s Algal Bloom Dashboard.
North Carolina has had no reports of adverse health effects in people associated with this algal bloom.
The N.C. Department of Health and Human Services Division of Public Health (DPH) routinely encourages the public to avoid contact with large accumulations of algae and to prevent children and pets from swimming or ingesting water in an algal bloom.
DPH suggests the following steps to safeguard against algal blooms: