Rangers patrolling Abiquiú Lake on Thursday were mystified when they came across suspicious-looking coloring in certain parts of the water, making it appear like thick pea soup.
They had reason for concern. On Tuesday, the U.S. Army Corps of Engineers announced it had closed the recreation area of the lake — including the swimming beach and boat ramp — after tests revealed the presence of a blue-green algae bloom.
“It looks like it is increasing because visually it’s more prevalent [Tuesday] than it was [Monday],” said John Mueller, operations project manager for the Corps of Engineers.
He said biologists are working on testing toxicity levels and the results should be available Wednesday. Until then, he said, “I don’t want to reopen the lake until I know that someone won’t get sick swimming in it.”
Blue-green algae blooms, which can carry cyanobacteria, can cause health problems for humans and animals if ingested, inhaled or touched. Skin exposure can lead to rashes, hives or blisters. Swallowing the water can lead to stomach pains, diarrhea and vomiting.
Other symptoms can include numb lips and dizziness. CNN and other media outlets reported this week that some dogs swimming in water contaminated with toxic blue-green algae in a North Carolina lake died after coming into contact with the bacteria.
The blooms can grow in fresh and marine waters and are the result of a number of factors — including the amount of sunlight available, high temperatures, low water levels and the impact of pollutants that may be in runoff water. Mueller said a lot of runoff water has been coming into the lake lately with the monsoon rainstorms.
New Mexico Environmental Department spokeswoman Maddy Hayden said in an email Tuesday, “Algal blooms are typical in the current conditions at Abiquiú Lake, which include high temperatures and low water levels. We often receive calls on algae around this time of year and the closure of the water body until conditions improve is typically the best response.”
The closure of the lake comes less than a week after the Environmental Working Group, a nonprofit environmental activism outfit headquartered in Washington, D.C., released a study saying tests show that blue-green algae is found “in hundreds of lakes, rivers and other bodies of water nationwide.”
That report says authorities do little to notify the public about such toxins. But it also says not all algae blooms are toxic.
Mueller said Abiquiú Lake has been used for recreation since at least the early 1980s. He said to the best of his knowledge, this is the first time that blue-green algae blooms have been found there.
The 4,000-acre lake, about 55 miles northwest of Santa Fe, is a popular spot for boating and swimming and is usually open from mid-April to mid-October. The peak season, Mueller said, is between Memorial Day and Labor Day weekend.
“It might get better, it might get worse,” he said of the algae situation. “We’re trying to monitor it. We would like to open as soon as possible, but if it gets worse, I’m not comfortable opening the lake until we know for sure it’s safe.”