The Army Corps of Engineers says to be aware of the water changing colors this summer and to be mindful of the effects. Turquoise discoloration is a growth of the bacteria commonly known as “blue-green algae” or cyanobacteria. Assistant Operations Manager at Lake Red Rock Perry Thostenson says that this algae is typically seen this time of year in Iowa lakes, rivers, and ponds because nutrient rich waters mix with summer heat. He says if you notice the turquoise discoloration, avoid being in contact or ingesting the water in that particular area. He says the toxins from the bacteria can cause skin irritation, burning eyes, and flu-like symptoms. He adds that they haven’t seen any of the blooms growing near any of the beaches at Lake Red Rock, and says most water in the lake is safe to swim in.