Send us a suggestion!

Virgin River Cyanobacteria

Discussion in 'General Discussion' started by NM Ben, Jul 14, 2020.

  1. NM Ben

    NM Ben

    Think this could have any implications on wet canyons in Zion once things open back up?

    "SPRINGDALE, Utah — Zion National Park is warning visitors not to swim or wade in the Virgin River after the water tested positive for a toxin caused by cyanobacteria.

    The Southwest Utah Public Health Department issued a public health warning about cyanobacteria in the Virgin River.

    According to the Environmental Protection Agency, cyanobacteria or blue-green algae often occurs in calm and nutrient-rich water. Some species of cyanobacteria produce toxins that can make people and animals sick. Algal blooms in Utah lakes forced health officials to issue several warnings to state residents in the past few years.

    Signs at Zion National Park warn visitors not to swim, submerge themselves, or allow pets to get in the water or drink it.

    In a news release, the National Park Service said it first learned about the cyanotoxin in the Virgin River because a dog died July 4, 2020, about an hour after swimming in the river’s North Fork.

    “Prior to its death, the dog exhibited symptoms consistent with possible exposure to cyanobacteria toxins — those produced by harmful algal blooms. The dog could not walk, was in pain, and was having seizures,” the statement said.

    Water samples taken from the river showed concentrations of anatoxin-a, the specific cyanotoxin involved, tested higher than 55 micrograms per liter in at least some of the samples.

    “The health threshold for primary recreation from the Utah Department of Health and DWQ [Division of Water Quality] is 15 micrograms per liter,” the statement continued. “Additionally, harmful cyanobacteria that produce anatoxin-a were identified in multiple areas of the North Fork of the Virgin River.”

    Health officials urge all visitors to the area to follow these guidelines:

    • Do not swim in the North Fork of the Virgin River, and do not put your head underwater
    • Do not drink the water from the river, even if using a filter or purifier
    • Avoid any areas with visible algal scum
    • Keep pets away from the water
    The Narrows hike, popular with many Zion visitors, requires hikers to wade through the water. The hike is still open, but park officials urge caution while following those guidelines."
  2. ratagonia


    Mount Carmel, Utah
    No. not really.

    The North Fork of the Virgin River flows from Navajo Lake (kinda sorta) through The Narrows, then through the Park, Springdale, Rockville and Virgin etc. eventually ending up in Lake Mead. The poisoning event took place in the Park near Canyon Junction, 8 miles below The Narrows. Evidence suggests that the algae bloom in question exists somewhere near(ish) to Canyon Junction. Further water tests are underway.

    As the bloom is generally caused by warm water that is fairly still, it seems unlikely that the infection is as far north as The Narrows. Also, hiking in the Narrows rarely involves swallowing significant quantities of river water, and humans rarely snap at algae in the water.

    In any case, it is rather unlikely that any technical canyons would have the algal bloom in them, or above them. Perhaps the exception is Kolob/Narrows, however, there are plenty of people monitoring Kolob Reservoir, and it's high altitude probably precludes algal growth.

    Dave Melton and Yellow Dart like this.
  3. hank moon

    hank moon kinetically bulbous

    Kind of a snap

Similar Threads: Virgin River
Forum Title Date
General Discussion Virgin River Comprehensive Management Plan Aug 22, 2013
Archives - Yahoo Canyons Group Virgin River Gorge Canyons, bolting/ trail building Jan 8, 2012
Archives - Yahoo Canyons Group Virgin River Gorge Dec 13, 2011
Archives - Yahoo Canyons Group Virgin River Flow and Echo Permits Jun 15, 2011
Archives - Yahoo Canyons Group Zion - open for comment - Virgin River Comprehensive River Management - ORV Nov 10, 2010
Archives - Yahoo Canyons Group Planning for Virgin River Management Oct 13, 2010