Cyanobacteria Importance to Drinking Water Facilities
Lake Champlain is the drinking water source for about 150,000 Vermonters. Cyanobacteria can potentially produce cyanotoxins that can cause illness to exposed human and animal populations. In addition to producing toxins, cyanobacteria can pose treatment challenges for surface water public water systems: pH increases, shortened filter run times, increased chlorine demand, increased turbidity, increased disinfection byproduct (DBP) formation, or altered taste and odor. Currently, the U.S. Environmental Protection Agency (USEPA) does not require testing for cyanotoxins; however, Vermont has a strong network of voluntary sampling and recommends water supplier initiated targeted monitoring.
Lake Champlain-sourced, as well as, other surface water public drinking systems are potentially vulnerable to cyanotoxins. In 2015, VDH issued health advisory levels for public drinking water systems for three cyanotoxins: Anatoxin, Cylindrospermopsin, and Microcystin. DWGWPD has established a practice which specifies protocols to be used when responding to a cyanobacterial bloom and cyanotoxin detection at or above the health advisory levels.
For more information, contact Sille Larsen, Engineering and Water Resources Section Supervisor.