Yes, there is a good chance that this is the explanation for why the Olympic pool turned green. There is a good chance that a chemical added to the water could react to pee. Furthermore, divers have said that they often pee when they hit the water when diving. Thus, this is a good explanation.
People can be unclean and do unsanitary things. I wouldn't put it past any Olympian that they would urinate in the pool at the competition. It would be good to have this chemical in more pools in case this actually works. This would put more shame in people so that they do not use pools as bathrooms.
Old pipes used copper, brazil has old pipes that is contaminating the water. Thus RIO should fix their pipes, preferably before a huge festival.
Either that its algea in the water. I would imagine the water being too toxic to form green tides, but eh maybe. The color is too clear for it to be algea though.
It would take a comically high amount of pee to color such a large volume of water, even if the chemical reacted in such a manner. However, pools worldwide are not turning green, which suggests that Rio is the only place this mystery chemical is used, which seems highly unlikely.
The entire pool would not turn green if somebody peed in it. The urine would be quickly diluted, only the surrounding water next to the offending swimmer would change colors. Do people not use their head to think with anymore? My five-year old son could have figured that one out.