A turquoise-colored Siberian lake may be Insta-perfect — but it’s actually an artificial, toxic waste dump, and the company operating the plant is urging visitors not to go into the water.

The lake, dubbed the Novosibirsk Maldives, is used to dump ash from a nearby coal plant, and contains chemicals that can cause allergic reactions, according to a statement posted to Russian social network VKontakte by the Siberian Generating Company.

“In the last week, our ash dump of the Novosibirsk TEZ-5 has become the star of social networks,” the statement said. “But you CANNOT swim in the ash dump. Its water has high alkaline environment. This is due to the fact that calcium salts and other metal oxides are dissolved in it. Skin contact with such water may cause an allergic reaction!”

The bottom of the dump is muddy, the company warned, adding that getting out of the reservoir alone is almost impossible.

“THEREFORE, WE ASK YOU VERY MUCH THAT IN YOUR QUEST FOR A SELFIE YOU DON’T FALL DOWN INTO THE ASH DUMP!” the statement continued. “THIS IS THE BIGGEST RISK.”

Instagrammers have flocked to the deceivingly pristine-looking lake and snapped photos as they posed in bikinis and took wedding photos on its shores — and even paddle-boarded in the middle of the toxic dump.

Perhaps the most outrageous post was a man who rode an inflatable unicorn on the water.

“It’s not dangerous to swim here,” the poster snarkily captioned the image. “The next morning, my legs turned slightly red and itched for about two days.”

Some photo-happy visitors say they have no hesitations about returning to the artificial attraction — but plan to stay at the shore.

“I just enjoy photography,” Leo Alexey, who set up a fan account on Instagram called “Novosibirsk Maldives.” “The place is really interesting although you cannot swim there because of the high content of calcium and metal oxides which may cause allergies.”

“I have been there five times, and I plan on going more,” he added. “I go there every weekend but I don’t touch the water.”