ST. GEORGE — A toxic algae bloom in the North Fork of the Virgin River continues to be a concern to local, state and federal officials as testing continues to determine how widespread and dangerous the neurotoxin created by the bloom has become.
“We’re continuing to monitor the Virgin River,” Jeff Axel, Zion National Park spokesman, said Wednesday.
One of the latest rounds of testing is related to the level of toxin exposure that could happen during recreational activity in the river, Axel said.
“We’re thinking about what people do in the water at the park,” he said. “It’s typically sitting in the water, kids are splashing around and lifting up rocks. You’ve got people hiking in the Narrows – what if they tripped and fell on their face and get some river water in their mouths? … We’re trying to figure out what the recreational exposure is.”
The National Park Service reported last Saturday that the algae-produced neurotoxin can be ingested though the eyes, mouth and nose and that a very small amount can be harmful.
Results from the latest batch of testing for possible recreational exposure are expected back from the state any day now, Axel said.
Called anatoxin-a, which is created by high levels of cyanobacteria that comes with algae blooms, it impacts the nervous system with accompanying symptoms that include skin rash, salivation, drowsiness, tingling, burning, numbness, pain, incoherent speech, seizures, vomiting and diarrhea.
Cyanobacteria is a naturally occurring substance that comes with algae, yet can become dangerously toxic in high concentrations.
The likely cyanobacteria blooming in the Virgin River is Microcoleus tychonema, according to the National Park Service.
“It forms colonies that can be red, yellow, tan, green, brown or black in color. It produces the cyanotoxin called anatoxin-a, which impacts the nervous system. The toxin was detected at levels in the park far above the recommended health threshold for primary recreation (swimming) at multiple locations.”
Park service and Washington County officials were alerted to the presence of the toxic algae bloom earlier this month following the death of a 5-month-old puppy over the July 4 holiday.
Keanna, a Siberian Husky pup, had been playing in the Virgin River and chewing on some algae on a rock. Within the hour, the dog was dead. Prior to that, the dog was reported to have had trouble walking and was having seizures.
The dog had been a gift from Vanessa Weichberger to her young son, Francis, according to a Go Fund Me page set up by Weichberger to help cover costs incurred by the dog’s final care.
Weichberger’s family was visiting Zion National Park from South Carolina when the incident occurred.
“The toxic algae killed her in about 20 (minutes),” Weichberger wrote on the fundraiser page. “We watched in shock and horror as she left us way (too) soon and so dramatically. My son was bereft and is still grieving.”
Anatoxin-a is particularly deadly to dogs and can kill them within 15 minutes. Because of this, anyone visiting the Virgin River for whatever reason is asked to keep their dog out of the water and on a leash at all times.
“This is scary, and this dog did die, so people should take it seriously,” Axel said, yet added that thus far, there is no record of a human fatality involving the neurotoxin, only incidents of illness.
As for the concentration of toxin in the river, Axel said 15 micrograms per liter is considered a warning sign, with 90 micrograms being a danger level.
According to the National Park Service, some water samples taken from spots along the Virgin River between Zion and Rockville were confirmed to have concentrations greater than 550 micrograms per liter. Parts of the LaVerkin Creek have also tested positive for high levels of anatoxin-a.
Thus far, the National Park Service has posted signs along the river in the park advising people to avoid the water. However, hikes like the Narrows that involve walking through the water remain open for the time being.
Officials in Springdale, which draws its water from the Virgin River, have reported they are testing the water they draw for culinary use daily, and so far no signs of the toxins have been found thanks to the water treatment procedures employed there.
The Washington County Water Conservancy District is also monitoring the situation and currently is not taking water from the Virgin River into its treatment plant of the Sand Hollow or Quail Creek reservoirs.
However, should the toxins be found in the reservoirs the water district is currently drawing water from, General Manager Zachary Renstrom said the district’s water treatment plant will be able to remove the toxin.
“We can handle a situation like that if it came in our treatment plant – the water is completely safe to drink,” Renstrom told St. George News.
For now, park and health officials are hoping a good rainstorm will come through the area and create a flash flood that can run down the river and possibly remove the algae, Axel said.
“So far, the weather’s not cooperating,” he said.
A strange aspect about the algae bloom is that is in a river – a moving body of water, rather than a stationary one like a pond or lake where blooms traditionally appear. Because of this, the case of the Virgin River algae bloom has drawn attention from across the country, Axel said.
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