Going to the lake in Kansas this weekend? First, make sure the water’s safe

Sonny Crawford fishes off a pier at Lake Afton on Friday. The lake is closed to skiing and swimming due to an algae bloom.
Sonny Crawford fishes off a pier at Lake Afton on Friday. The lake is closed to skiing and swimming due to an algae bloom. The Wichita Eagle

If you’re going to a lake in Kansas anytime soon, you may want to check to see if the water is safe first.

In Kansas, 17 bodies of water, including Lake Afton, are under a blue-green algae warnings or watches, according to the Kansas Department of Health and Environment.

Lakes under a warning are closed for water contact activities, including swimming and water skiing for people and their pets, but they remain open for other activities. People and pets should avoid water contact at lakes on the watch list, as the water may be unsafe and blooms can be unpredictable and happen between when water is tested and when a warning is issued.

The department maintains a list of lakes under warnings that’s updated weekly.

“People should take warnings very seriously,” said Mark Schneegurt, a biology professor at Wichita State with a deep background in the study of cyanobacteria, like blue-green algae.

“Intoxication with these poisons can kill you and your pets,” Schneegurt said. “Some folks will be more sensitive than others, but these are such powerful toxins, that people should stay away from waters with an active cyanobacterial bloom. Over time, as the bloom dies out, the toxins are naturally degraded, and the water will become safe again.”

Thirteen bodies of water in Kansas were under blue-green-algae warnings, as of Friday. Besides Afton, Atchison County Park Lake, Carbondale West Lake, Central Park Lake (Pond) in Shawnee County, Frazier Lake in Grant County, Hodgeman County State Fishing Lake, Lake Wabaunsee, Marais Des Cygnes Wildlife Area, Melvern Outlet Pond, Melvern Swimming Pond, Perry Lake, Rooks County State Fishing Lake, South Park Lake in Johnson County and Webster Lake were all under warnings.

Four bodies of water have been added to the watch list: Central Park Lake in Shawnee County, Mary’s Lake in Douglas County, Overbrook City Lake and Rock Garden Pond in Gage Park.

Contact with blue-green algae can be harmful, causing skin irritation, stomach cramps, vomiting, nausea, diarrhea, fever, sore throat, headache, muscle and joint pain, blisters of the mouth and liver damage. Swimmers in water containing toxins from blue-green algae may suffer allergic reactions, such as asthma, eye irritation, rashes, and blisters around the mouth and nose, according to the World Health Organization.

Fishing is still allowed in legal areas, but anglers wishing to eat their catch should follow Kansas Department of Health and Environment guidelines, the statement said. The guidelines include washing hands and arms and catch with clean, potable water after fishing. Only skinless fillets of fish caught in a lake with blue-green algae should be eaten.

“If there is scum, a paint-like surface or the water is bright green, avoid contact and keep pets away,” said Theresa Freed, a spokeswoman for department of health and the environment in a news release. “These are indications that a harmful bloom may be present. Pet owners should be aware that animals that swim in or drink water affected by a harmful algal bloom or eat dried algae along the shore may become seriously ill or die.”

What is commonly called blue-green algae is not algae at all — it’s actually a bacteria that can produce fatal toxins.

Here’s how blue-green algae blooms work, according to Schneegurt.

A population of blue-green algae live in a lake. The bacteria growth is limited by the availability of an energy source — either a limited amount of nitrogen or other nutrients, like soluble iron or phosphorus — in the water.

During the growing season, farmers and homeowners fertilize their crops and lawns, which often place a lot of nitrogen and other energy sources for blue-green algae close to the lake. All it takes is a good rain for these nutrients to flow into the lake, or they can show up through groundwater and runoff.

Once the bacteria have an available energy source, they bloom wildly.

Blue-green algae blooms often look like spilled green paint floating on the surface.

Eventually, the bacteria use up all of the nutrient and start to die, called bloom and bust. Their corpses are eaten by other bacteria, which can grow rapidly and remove oxygen in the water, causing fish to die and the lake to stink.

“There will be signage at all of the entrances and the bait shop and the swimming area and boating docks with warnings, so people will know not to go in the water,” Flavin said.

Flavin said there is staff assigned to the lake, but did not say whether they would be patrolling the area on the weekend.

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