Visitors to Curecanti National Recreation Area are being asked to avoid contact with water in the Iola Basin/NPS

A strain of algae that can kill dogs has been detected in a section of Blue Mesa Reservoir at Curecanti National Recreation Area in Colorado. For now the Iola Basin area of the reservoir has been closed to swimming.

Testing has found the presence of cyanotoxins in the Iola Basin in concentrations that exceed safe exposure levels, a National Park Service release said.

Along with closing the water to swimming -- "full body contact" --, the park is urging caution and saying visitors should avoid unnecessary exposure to reservoir water if fishing, boating, or recreating as other areas of Blue Mesa Reservoir may contain these toxins, the park's release said.

Boating and fishing remain open throughout Blue Mesa. Clean harvested fish in treated water. As always, remember to clean, drain, and dry all boats and fishing gear.

Do not let dogs or other animals drink water from any portion of the Iola Basin. Until further notice, the park recommends that dogs not swim in or drink reservoir waters.

Contact medical care (doctor or veterinarian) if, after exposure to the water, individuals or pets exhibit nausea, vomiting, digestive distress, breathing problems, seizure, or unexplained illness.

Harmful algae, also known as blue-green algae, is common and natural to the park's waters and found throughout Colorado. The algae can multiply rapidly to form blooms and scums, particularly in areas of shallow, warm water. 

Water quality staff are sampling and monitoring the situation. Watch the park's website for updates and advisories.