Monitoring and Evaluation of Cyanobacteria in Burlington Bay, Lake Champlain (2001), LCBP Technical Report #40

Watzin, M., Shambaugh, A., Brines, E.K., & Boyer, G. (2002). Monitoring and Evaluation of Cyanobacteria in Burlington Bay, Lake Champlain (2001) (Technical Report No. 40). Grand Isle, VT: Lake Champlain Basin Program

This report presents a study that analyzed the possibility of human exposure to the toxins produced by cyanobacteria (blue-green algae or BGA) that killed two dogs in 1999 near Juniper Island. This was tested by analyzing lake water samples from around Burlington in conjunction with data acquired by New York and Vermont State field personnel. The study concluded that the environmental conditions around Burlington in the summer and fall of 2001 were not conducive to the growth of large BGA blooms capable of producing dangerous levels of toxins. However, it was found that potentially harmful blooms could occur when the conditions were more favorable to BGA accumulation. The study also found that the likelihood of toxin ingestion through municipal water intakes is low given that they draw water from deep in the lake, whereas BGA blooms typically occur on or near the surface. BGA contamination however, should be a potential concern for water treatment facilities whose intakes are at shallow depths. The study concludes that when the conditions are right, toxin producing BGA blooms can occur in the Burlington area. This means that swimmers and pets should avoid the water when blooms are visible to minimize or prevent exposure. The report advises that it would be beneficial to implement a tiered monitoring and alert system used to inform people about the presence of and risks associated with BGA toxin. This system could be used by the NY and VT Departments of Health, drinking water treatment facilities that draw from the lake, beach managers, recreational users, and home and camp owners who draw water from the lake. Note: Data are available in report.