The City of Moore has instructed residents to be cautious of ponds and standing water in city parks over concerns of blue-green algae.
A bloom at a dog park in Edmond prompted organizers to close off the pond to visitors earlier this week. City Manager Brooks Mitchell said samples have been taken and sent off for tests to see if blue-green algae, which can be toxic to humans and animals and reportedly has killed dogs in other states, is present.
“We don’t know for sure. We took samples this morning and sent them off to the lab,” Mitchell said on Friday. “We’re erring on the side of caution. We don’t want someone to be walking beside the pond and fall in, or for kids to fall in or a dog to go in.”
Samples were taken from ponds at Little River and Buck Thomas parks, Mitchell said. Results could be in sometime next week.
The City of Norman is not aware of any blue-green algae blooms in its park ponds, and the Water Treatment Plant has not noticed an increase in Lake Thunderbird, according to a statement. Both the City of Norman and Mitchell asked residents to exercise caution, as this is the time of year algae blooms can occur.
“In light of recent high temperatures, residents are reminded of the potential for algae blooms to occur in stagnant water and are asked to use caution when allowing pets and children to enter stagnant water,” the statement read.
Earlier this week, a blue-green algae bloom was confirmed through tests at the Edmond Dog Park located Bickham-Rudkin Park, prompting officials to close off the park. This followed the story of a North Carolina woman whose three dogs died after they played in a pond that contained a blue-green algae bloom.
In Austin, officials are monitoring a bloom of toxic algae in Lady Bird Lake that has resulted in numerous dog deaths. It is common at this time of the summer to see algae blooms, said Dave Hambright, University of Oklahoma professor of biology and an expert in freshwater algae blooms.
Many types of algae are harmless, but simply use the warm water to rise to the surface and the warmth of the sun to grow, just like plants. Blue-green algae are actually cyanobacteria, Hambright said, and this is what makes them problematic.
“Blue-green algae are actually bacteria that have photosynthetic capability,” he said. “So they’re quite different from algae. What they’re really good at is growing in really harsh conditions. They’re really hearty creatures. They like the conditions of summer here.”
Blue-green algae feed off of the nutrients that enter lakes and smaller retention ponds from both natural and urban runoff. The spring rains wash these nutrients — such as yard fertilizer — into standing bodies of water.
Algae then uses the warming water to rise to the surface, where they bloom. Sometimes, blue-green algae beats other types of algae to the surface, Hambright said.
“They have mechanisms that let them float to the surface to take advantage of high temperatures,” he said. “They also do very well in super-high nutrients conditions. With the agricultural and urban runoff, we’ve finally gotten urban wastewater pretty much under control, but it’s the non-point sources of runoff ... they’re not very controllable.”
That alone is not enough to cause risk to the public or their pets. The issue comes with swimming in or drinking untreated water from bodies of water containing large volumes of cyanobacteria.
Dogs are at a particular disadvantage for a few reasons, Hambright said. For one thing, they tend to clean themselves after swimming.
“We don’t lick ourselves clean. Dogs do,” Hambright said. “A lot of these cyanobacteria, they have these gelatinous sheaths, and they’re sticky to dogs. They’re basically ingesting lots and lots of algae, and that’s incredibly high doses.”
Cyanobacteria also release toxins into the water when they die, making untreated water dangerous for consumption. It also makes killing off the blooms more difficult, since causing a large mass of cyanobacteria to die doesn’t really fix the toxicity problem.
Instead, blue-green algae blooms take care of themselves as the seasons change. Hambright said once temperatures cool down, the lake starts to “turn over,” taking cooler water up to the surface and taking the cyanobacteria down deeper where they struggle without sunlight.
So eventually, the issue will take care of itself. But, Hambright said with climate change bringing more rain in the spring and hotter, longer summers, the issue of algae blooms isn’t going away.
“You start getting these climate patterns of summer being longer and warmer, more rain in the springtime and more drought in the summer,” he said. “All of that adds up to making good conditions for blue-green algae.”
It’s best to take care when swimming in stagnant water this time of year, Hambright said. If the water looks green and feels hot, it’s best to stay away and keep pets out of it, too.
“If it’s a body of water of concern, call the DEQ (Department of Environmental Quality) or the [Oklahoma Water Resources Board,]” he said.
If a dog does make its way into a pond where a blue-green algae bloom is possible, it’s best to take them out as soon as possible, bathe them immediately and not let them lick themselves. Monitor the dog and if symptoms of ingestion occur — tiredness, vomiting or seizures — take it to the vet immediately, Hambright said.
Blue-green algae blooms are not a problem for most lake goers, Hambright said. Boaters at Lake Thunderbird won’t come across the blooms, since they stay close to shore.
And the blooms are not an issue with drinking water, Hambright said.
“Right now, if you walk up to a lake and there’s no sign it’s bad, that doesn’t mean anything,” Hambright said. “It just means no one has checked yet.”