Virginia Regulatory Town Hall
Agency
Virginia Department of Health
 
Board
State Board of Health
 
Guidance Document Change: The Guidance for Cyanobacteria Bloom Recreational Advisory Management requires revision for the Harmful Algal Bloom (HAB) response season, beginning in April 2025. The proposed revision includes the DEQ and VDH staff recommendations, which allow for more extensive and targeted monitoring of algal toxins in recreational freshwater areas during a HAB, and for using toxin data alone for recreational advisory determinations. These recommendations are based on a review of current processes for HAB monitoring and managing recreational HAB advisories, final recommendations from the U.S. Environmental Protection Agency (EPA) on protecting human health risks from incidental ingestion while recreating in freshwaters, data collected from Virginia HAB investigations with paired cell counts and toxin assays, and budget and staff efficiencies. This approach is supported by both VDH and DEQ agency secretaries.
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5/21/25  11:20 am
Commenter: Mark Richards

HAB Advisory Protocol Change
 

As a property owner on Smith Mountain Lake, I have concerns about the change to the existing HAB guidance document for Recreational Advisory Management. The policy change is apparently supported by an over simplified analysis of a 406-sample dataset that includes paired cell counts and toxin assays. The analysis concluded that there is no correlation between cell counts and toxin concentrations. To ensure complete transparency, the dataset should be made available to the public, and should include important data elements such as sample date, location, cell counts, when sample collected within the bloom cycle, cyanobacteria species (if available), targeted analyte, analytical method, detection level, reporting level and the result. Despite the general conclusion of no correlation between cell counts and cyanotoxins, knowing there are cyanobacteria species that produce greater (or multiple) toxin concentrations based on cell count is crucial for informed management actions. Given the complexity of this issue, it makes more sense to approach advisory decisions using multiple lines of evidence that also takes cell counts into consideration.

CommentID: 236088