The color of the two pools at the Maria Lenk Aquatics Center has been a surprising storyline at the 2016 Rio Olympics. Take a look at how the diving well and the synchronized swimming/water polo pool have changed with each day of competition, going first from blue to an inexplicable green. Now, after being drained and refilled, the water polo/synchronized swimming pool is back to blue again. But the diving well remains green. Officials have said that there was no health risk associated with the green water.