The diving pool and the neighboring water polo pool at the Rio Olympics turned green. Initially, explanation for the change in color (the water had once been the proper blue) ranged from a sudden change in alkalinity to a shortage of proper chemicals to treat the pool to an algae bloom. Maybe it was just poor circulation in the venue. Now Olympic officials say the green color was caused by the improper use of hydrogen peroxide by the contractor which neutralized the chlorine and allowed organics to grow. And the pools have had to be drained.
But it’s safe. Even though athletes were complaining of eye irritation. And the water smelled. And the condition of the pool was getting progressively worse as organics were allowed to bloom. Experts said they wouldn’t swim in it.
The pools were green for 4 days. With athletes practicing and competing in them. It took 4 days for Olympic organizers to figure out what went wrong. If the green pools are truly the result of the work of an independent contractor this may explain the delay in explanation. But not the delay in fixing the problem. Or the perhaps larger issue of ignorance and incompetence with how Olympic venues are being maintained.