Good as gold - China's Shi Tingmao (left) and Wu Minxia show off their gold medals during the awards ceremony of the women's 3m Springboard Syncronized final diving event at the FINA World. Photos provided to China Daily

FINA, the Federation Internationale de Natation, used to ask organizers to put a roof on the outdoor venue and complained openly about it to Rio's Mayor Eduardo Paes. The city declined to spend the money, and said the federation was too demanding.

In a letter to the mayor from FINA, the swimming body said conditions like those at the diving venue "will negatively affect the safety conditions and the level of performances of our athletes".

Cornel Marculescu, the executive director of FINA, acknowledged the letter but said that FINA had to be satisfied with what the organizers provided.

"It's not a matter anymore to complain, it a matter now to do the best event possible,"Marculescu said. "Evidently, it's much better if you have it indoors, but we have to run the best possible event in these conditions."

The power supply is also affected. The first two days' competitions sustained temporary power failures with the broadcast's large screen interrupted and reporters from around the world had to work in a dark media center at times.

The outages had an impact on four-time Olympic gold medalist Wu Minxia of China, who won the women's synchronized 3m springboard with her partner Shi Tingmao on Feb 20.

"In the first round of our final, we even don't know the result because the screen didn't show it," Wu said.

Brazil's Zika virus outbreak also had made some athletes and tourists fearful of being in the country. The Olympic host country has had 1.5 million people infected by Zika since early 2015.

While it causes only mild flulike symptoms in most people, scientists suspect when it strikes a pregnant woman, it can cause her baby to be born with microcephaly, or an abnormally small head.

According to Chinese diving team manager Zhou Jihong, the organizing committee has provided repellent to teams and also raised awareness about Zika prevention. A daily sweep of the venue will be conducted to remove mosquitoes.