Updated 10:30 p.m. Aug 3 with new information.
Update 2: According to the Idaho Department of Parks and Recreation, the waterways of the Eagle Island State Park have been cleared of blue-green algae and have been re-opened for public use.
Update 1: Idaho Department of Parks and Recreation began treating the blue-green algae contamination in Eagle Island State Park on July 24. It is estimated that treatment and monitoring will take 10-14 days. Once deemed safe, swimming will once again be available in the park. On July 25, it was confirmed that harmful toxins form cyanobacteria were present.
The Idaho Department of Parks and Recreation restricted water access to the pond at Eagle Island State Park after a blue-green algae bloom was detected on July 17.
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A 1-year-old dog reportedly died July 17 after swimming in algae-contaminated water in the Henry’s Fork of the Snake River, near Rexburg. This prompted the Idaho Conservation League to release a statement calling for statewide action to reduce pollutants that are partially responsible for the algae blooms.
At high levels, potential toxins from the algae can sicken people or animals who ingest contaminated water.
The state parks department is working with the Idaho Department of Environmental Quality to test the water at Eagle Island for potential toxins. The results of these tests are expected in a couple of days, said Jennifer Okerlund, parks department communications manager.
Until then, parks officials restricted access to water at Eagle Island State Park until the water is deemed safe.
“Our primary concern is the safety and well-being of our park visitors,” Okerlund said in a statement Wednesday. “If there’s even a suspicion that water in the park could be harmful, we would rather error on the side of being overly cautious.”
Blue-green algae are actually microscopic bacteria known as cyanobacteria and are a natural part of the ecosystem. They are named for their blue-green color (cyan), but blooms can appear as green, yellow, red and brown as well.
Their populations can explode under the influence of abundant nutrient sources, things rich in phosphorus and nitrogen such as fertilizers that make it into the water supply. Sunny conditions and warm temperatures also can contribute to their growth because cyanobacteria get their energy from photosynthesis, as do plants.
Like plants, many cyanobacteria produce oxygen. In fact, scientists think that most of the oxygen in our atmosphere originally came from these creatures. Other types produce hydrogen sulfide, a harmful gas that has the smell of rotten eggs. Cyanobacteria also can produce nerve and liver toxins that can harm animals and humans if the algae population reaches high enough levels. It is these toxins that Department of Environmental Quality is testing for.
“Toxic algae that kills our pets and our fish is also unhealthy for humans,” said Austin Hopkins, conservation associate with the Idaho Conservation League. “As our summers grow hotter and drier, we are seeing more and more of these outbreaks. Doing nothing is unacceptable.”
As a general rule, people should avoid all contact with water that contains algae. Pets and livestock also should be kept away. When in doubt, stay out of the water.
Symptoms that can develop after swimming in water containing high levels of cyanobacteria include skin rashes and eye/ear irritation. Symptoms of ingesting water with algae toxins can include headaches, nausea, fever, sore throat, dizziness, stomach cramps, diarrhea, abdominal pain, vomiting, muscle aches, mouth ulcers and blistering of the lips.
If you experience any of these symptoms after swimming in or drinking potentially contaminated water, seek medical attention.
For more information about harmful algae blooms and a map of current advisories in Idaho, visit http://www.deq.idaho.gov/water-quality/surface-water/recreation-health-advisories/.