Organizers of the ITU World Triathlon promised athletes an update within 48 hours of Wednesday to let them know if the swim portion of the race will go on.

Alberta Health Services found a blue-green algae bloom in the Hawrelak Park lake Tuesday, just 10 days before the international race comes to Edmonton.

It’s unknown why the algae bloom occurred this year, since city staff said they haven’t noticed blooms in the past. During the winter of 2013, the city drained the lake, dug a deeper swimming channel and repaired the liner in advance of last year’s world final event.

A team of experts will look at every option, from draining and refilling the lake to pumping large amounts of oxygen through the water, in an attempt to get rid of the toxin in time for the race.

“It’s all hands on deck for those individuals to determine how to move forward,” said Rob Smyth, community and recreation facilities manager for the city. “This is absolutely critical.”

Dr. Chris Sikora, medical officer of health for the Edmonton Zone, said officials visited the lake in preparation for the triathlon, but even before they took water samples, knew there was a problem.

The lake has taken on a green, pea-soup appearance, he said.

Samples came back with readings from 5,000 to 1.2 million parts per millilitre, far more than the 100,000 parts per millilitre threshold considered safe.

A toxin left in the water by the algae causes an itchy rash if it comes into contact with skin. If swallowed, it can cause nausea, vomiting and diarrhea.

“We do have time to be able to remediate,” said Sikora. “If (the triathlon was) held today, it wouldn’t be a good idea. ... Every swimmer I’ve known ingests water.”

Sheila O’Kelly, general manager for the local organizing committee, said the worst-case scenario would see organizers cancel the swimming portion of the event and just have athletes bike and run, as was done once in New York. But the team will also be looking for alternate venues. The absolute last minute they can make a change is 4 p.m. the Friday before the race, when they update the approximately 1,000 athletes expected to compete here in Edmonton.

The ITU world triathlon is scheduled for Hawrelak Park on Sept. 5 and 6.

“I said, ‘No, no, no!’ ” said athlete Paul Wallace, describing his reaction when he heard of the algae bloom.

Wallace is also the chair of the local triathlon club. The 44-year-old IT network administrator has been training seven months to compete in his age category, hoping to earn a chance to compete at the world championship next year.

There are 10 spots available in each age category for the sprint distance, a tantalizing prize likely attracting athletes for miles around, he said. “If you can come in under one hour, 10 minutes, you have a strong shot at going to Mexico.”

But swimming is his strong sport. If the 750-metre swim is cancelled, “there goes my advantage.”

At noon Wednesday, Don Lowry, chair of the World Triathlon Series for Edmonton, said officials will have another update for athletes and the public in 24 to 48 hours.

Safety for the athletes will be the primary concern, he said. “Even if someone has to scratch their head and say, ‘I’m not sure,’ we’re not going ahead.”

Athletes should still be training hard, he said.

For the general public, AHS issued a health bulletin advising people to avoid contact with any visible blooms, and not to swim, wade or allow pets to enter areas where the blue-green algae can be seen.

Areas of the lake in which algae is not visible can still be used for recreational purposes, the bulletin said.

Blue-green algae, also called cyanobacteria, is naturally occurring when nutrient levels, air temperature and sunlight conditions are appropriate. It appears like scum, grass clippings, fuzz or globs on the surface of water, the advisory said, and can be blue-green, greenish-brown, brown or pinkish-red, and often smells musty or grassy.

With files from Cailynn Klingbeil

estolte@edmontonjournal.com

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