The Olympics swimming pools turned green after hydrogen peroxide was dumped in the water, organisers revealed on Aug 12.

8月12日组织者表示：奥运泳池的水变绿是因为投入了过氧化氢。

A contractor¹ poured 80 litres of the chemical into both the diving and water polo pools on August 5, the day of the opening ceremony, but the mistake only emerged when the water started to change colour on Tuesday.

8月5日，有承包商在潜水池和游泳池倒入了80公升的化学药品，就在开幕式的那一天——但是周二的时候水开始变色了，问题才暴露出来。

The hydrogen peroxide, more commonly known as bleach², neutralised the chlorine in the water, allowing algae³ to bloom and turning the water green.

过氧化氢——更为人熟知的名字是“漂白剂”可中和水中的氯，会促进藻类富营养化并让水变绿。

之前奥运池水变绿这事儿可谓是掀起轩然大波：

There were farcical scenes at the Olympic synchronized⁴ diving final tonight after the pool turned a murky⁵ shade of green.

在水池变成墨绿色之后，奥运双人跳水决赛上出现了滑稽的画面。

The five-metre deep diving pool - which was a normal blue colour during the men's event last night - appeared to slowly turn greener as the competition went on.

昨晚进行男子跳水项目的时候，这5米深的跳水池还是正常的蓝色，然而，随着比赛的进行，池水似乎逐渐变绿了。

British Bronze medal winner Tom Daley noticed the change, tweeting: 'Ermm... what happened?!'

获得铜牌的英国选手汤姆·戴利注意到了这种变化，于是发推文，写道：“额……，发生了什么？！”

Rio officials at the Maria Lenk Aquatics⁶ Center have so far been unable to provide an explanation.

到目前为止，里约奥运会玛利亚·伦克水上运动中心的官员们还无法给出一个（合理的）解释。

Left, how the water appeared on Tuesday morning, and right, how it looked on Tuesday afternoon.

左边是星期二早上池水的颜色；右边是星期二下午池水的颜色。

Need goggles⁷? It was almost impossible to spot the divers⁸ as they swam back to the surface of the murky water after diving in.

需要护目镜？选手跳入水中之后，在他们游向浑浊的水面的时候，几乎都要找不到他们了。

There's much speculation⁹ as to what's going on but so far, no definitive¹⁰ answer.

关于这（池碧水）到底是怎么一回事，大家已作出众多猜测。然而，到目前为止，还没有定论。

Several people have speculated that the change is due to algae in the water, perhaps because the pool is lacking in chlorine.

一些人推断，这种变化是由于水中的藻类，也许是因为池水中缺氯。

Other theories suggest because pool is outdoors, it can accelerate algae growth if the water is exposed to the sun.

其他人指出，因为水池在户外，如果池水暴晒于阳光下，则会加速藻类生长。