NBC Olympics.com – Much and more has been made about the water color at the Maria Lenk Aquatics Center, which inexplicably turned green overnight on Tuesday. Rio 2016 director of venue management Gustavo Nascimento and Rio 2016 Organizing Committee executive director Mario Andrada addressed the media on Saturday to explain what really happened.
Nascimento cited two main sources for the color change: The mistaken introduction of 80 liters of hydrogen peroxide and the expected introduction of 120 athletes.
"We investigated and found that on the day of the Opening Ceremonies of the Games, 80 liters of hydrogen peroxide was put in the water," Nascimento said. "This creates a reaction to the chlorine which neutralises the ability of the chlorine to kill organics.
"We have an electronics system that measures the amount of chlorine in the water because chlorine is what kills the organics. This electronic management system was betrayed by the chemistry that was inserted manually by one of our contractor's operators. Our contractor's failure is our failure.
"What happened was that the electronics system found that the chlorine amount was OK in the water. The problem was that the chlorine in the water was somewhat neutralised. It was asleep and not killing organics.
"Due to the insertion of 120 athletes in the diving tank and the extended period of time the athletes of water polo stay in the water, the amount of organics in the water grew."
The pool used for synchronized swimming and water polo, which began to turn after the diving pool and not to the same extent, was drained and refilled with 3,725,000 liters of water from an adjacent practice pool, which was unaffected.
However, the diving well was not drained.
"On the diving tank, since there are not huge complaints about the performance of the athletes and the health and safety of the athletes, we are renovating the sand systems of the filters," Nascimento said. "The filters that we have here at Maria Lenk are sand filters which trap the solids which are in the water and make the water transparent. We are finalizing the exchange, we have finalized one and should have the second one done by the end of the day. We truly hope that in the first 12-hour cycle, we are going to see a sensible reaction on the overall aesthetics of the water. The chemicals of the diving tank are in very good condition."
Despite the green color, officials have maintained throughout that the water does not present any health risk to its entrants. And if anyone was concerned about metals in the water, Nacimiento put those to rest.
"There are no metals in the water," he said. "There is a lot of speculation regarding metals in the water, but there is 0.05 milligrams per litre of water of iron. It's almost nothing."
Close to a week after the color changed, Andrada didn't shy away from the problem, owning up to the mistakes he and his team made.
"Of course it is an embarrassment because we are hosting the Olympic Games, the world is here, the best athletes are here, so the water comes to be an issue," he said. "It should be light blue, transparent, and also things could have been done better, quickly. We learned painful lessons the hard way."
"What we failed (to do), or I failed in communication, was promised that the problem would be fixed next morning, so we promised and did not deliver. It should be the opposite."