Sapulpa, Okla. - Park rangers are discouraging swimming in the Sheppard's Point area of Heyburn Lake, after tests showed elevated levels of blue-green algae there.
The Army Corps of Engineers say the level is below the toxicity threshold set by the World Health Organization, but because the algae can make people sick or irriate skin, they're advising people to be cautious.
Ross Adkins with the Army Corps of Engineers says they're not sure why the algae is showing up at higher levels at Heyburn Lake.
He said the lake level is slightly below normal, but it's not that low.
"When it's down low, and there's not a lot of movement, that's when it has a chance to proliferate," he said.
So far he says they've not found high levels of blue-green algae in any other area lakes.