Warning Advisory for HABs Issued for Jordan River and Canals

The Salt Lake County Health Department (SLCoHD) issued a Warning Advisory for the Jordan River and its canals after samples showed levels of anatoxin-a that exceeded the recreation health-based threshold.

Jordan River

Warning Advisory sign for harmful algal blooms. Click for larger view.

Health officials advise people to stay out of the water and keep dogs from entering or drinking river water. Toxins present at this level have not been shown to present a health threat to people kayaking or boating on the surface of the river, but recreationists are advised to avoid areas of scum. SLCoHD also advises caution for the entire river, as cyanobacteria and toxins can spread and conditions change quickly.

The Utah Department of Agriculture and Food (UDAF) reports that toxin levels are far below the point where they would issue an advisory for livestock water or have cause for concern for agricultural irrigation.

Samples collected at the Jordan Narrows where the Jordan River enters Salt Lake County, Blackridge Reservoir in Herriman, and at the Wheeler Farm East Canal detected very low levels of anatoxin-a, a potent neurotoxin.  SLCoHD posted warning signs at Wheeler Farm in Murray and Blackridge Reservoir in Herriman, as much of this water comes from the Jordan River and both are popular recreational points. No potentially affected water bodies in Salt Lake County will be closed to access at this time.

SLCoHD will continue to monitor and sample the Jordan River at its entry point into Salt Lake County, Blackridge Reservoir, and Wheeler Farm and will update advisories as necessary.

Toxin Test Results

Lab results from the Utah Department of Agriculture and Food (UDAF) lab:

  • Jordan River at the Jordan Narrows: 0.45 micrograms per liter (µg/L) of anatoxin-a; 0.55 µg/L of microcystins
  • Blackridge Reservoir-Herriman: 0.47 µg/L of anatoxin-a; 0.19 µg/L of microcystins
  • Wheeler Farm East Canal: 0.53 µg/L of anatoxin-a; 0.56 µg/L of microcystins

Warning Advisory for Jordan River and Canals

A Warning Advisory indicates a moderate relative probability of acute health risk, cell-count density of 20,000 – 10 million cells per milliliter (cells/ml), microcystin levels of 4-2,000 micrograms per liter (µg/L), or anatoxin-a levels above non-detect. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

See the full press release.