Paul Sancya / AP, file
Algae floats on the surface of Lake Erie’s Maumee Bay in Oregon, Ohio, Sept. 15, 2017. Algae blooms can crop up in Nevada lakes this time of year, but reporting tools give environmental officials the ability to respond before it becomes a problem.
Thursday, July 4, 2024 | 10:50 a.m.
Blue-green algae are a normal part of Nevada's aquatic ecosystems. However, when algae encounters nutrient pollution or warming water temperatures, it can reproduce at a rapid rate and lead to an algae bloom.
Some blooms, known as "harmful algal blooms," can produce toxins. Nevada's prime time for these is between June and October.
"Cyanobacteria are a photosynthesizing bacteria that live in every water body in the country and in the world," said Weston Fettgather, a supervisor with the state Bureau of Water Quality Planning. The agency's job is to determine if the algae "produce compounds that are toxic to humans and animals," he said. "And so when these blooms get really big and they're producing these toxins, they can be dangerous to people and pets and livestock."
His agency is part of the Nevada Division of Environmental Protection.
"What we're seeing in the past few years in Nevada is an increase in the magnitude and frequency of these nuisance blooms," he said. While "it's difficult to pinpoint the exact reasons why a specific bloom is occurring," he said some contributing factors are "rising air and water temperatures, and also nutrient concentrations in water bodies."
"The main reason why water bodies are impaired in Nevada is due to nutrient bloating," Fettgather said. "When there's excessive nitrogen and phosphorus in warm water, those conditions promote these blooms getting really large. So because we expect to see these blooms continuing to happen and potentially even happening more often and for them to be bigger, it became really apparent that we needed to kind of assemble a group of state experts who can address the problem and put together a plan for monitoring and responding to these events with the express purpose of protecting public health."
He described doing that as "really challenging" because the blooms move around in the water.
Because of this, his agency works closely with others with staff near the water, such as the Division of State Parks and the Department of Wildlife. "They have staff on a lot of the lakes every day," Fettgather.
"Another important element to our program is educating the public. Because, like I said, these blooms can be difficult to pinpoint. If there are no state staff on the ground, it could be that a member of the public will be the first to actually see a bloom occurring. And so if people know what they're looking at, then they can keep both themselves and their family safe, but in addition, they can report those incidents to those so that we can further investigate," he explained.
He suggested people planning to be on the water check the Nevada HAB Dashboard at https://nvose.org/programs/environmental-health/harmful-algal-blooms-eh/.
Fettgather said the public should learn what cyanobacteria blooms look like, since there are others that don't produce toxins, but still can be a nuisance, such as green algae.
"There's green algae in just about every water body, especially in the middle of the state. So, I think it would behoove people to learn how to differentiate between green algae and cyanobacteria," Fettgather said.
Harmful blooms "can be easily identifiable, forming an apparent 'scum' or discoloration on the water surface," the Nevada Department of Environmental Protection website says. They "can appear green, blue-green, green-brown or red and can take on a handful of forms." Further, they could "cause water to look like paint or pea-soup, form scum, bubbling or spitlike foam or resemble lettuce or chopped grass." The website says the harmful blooms also can have a distinctive smell "that can be fishy, rotten or gasolinelike."
"If people do spot something, then, to protect themselves and everybody else, I think it's really important that they say something," Fettgather said. He said people should report blooms, with a photo, directly to him at [email protected].
He shared some tips for safety around the harmful blooms, such as when catching fish, rinse the fish and only eat filets. In addition, he said, dogs "are very susceptible" to the toxins produced by cyanobacteria, which could be fatal to them. So dogs shouldn't swim in or drink water with the bad algae. "In fact, there have been reports of dogs dying just from licking their fur after swimming in a lake that had an active bloom happening," Fettgather said.
A task force to fight these dangerous blooms was formalized this year and includes several Nevada state organizations as well as "local stakeholders, water body managers, researchers and people who work in and around water bodies that could potentially have harmful algal bloom incidents," Fettgather said.
He said the department is going high-tech with tools to monitor for blooms. "One of them is a satellite-based remote sensing tool. So we're actually using sensors on the Sentinel-2 satellite that record color data on water bodies all over the world," he said. "This is information that's updated daily. The satellite passes over daily, and we plug that into an algorithm that was developed by NASA and the EPA and NOAA. Those color values, once they go through this algorithm, it spits out information that gives us an idea of cyanobacteria cell concentrations in the water."
The idea is to help officials understand "what's happening in all the water bodies across the state, without having to have people on the ground."
"Another cool thing that we're using is a somewhat portable cyanotoxin-detection device, and this allows us to collect water samples and get toxin concentration results, typically within about 48 hours, sometimes within 24 hours," Fettgather said. "That's a really great advantage, because before we had that, we had to send samples out to a laboratory to be analyzed, and it could be about two weeks before we would know what the actual toxin concentrations were in the water on the day that we had collected the samples."
He said both tools will help keep the public informed and maybe keep a person or pet from swimming in the hazardous water and becoming ill.
