RIO DE JANEIRO (AP) Police investigators took samples at some of Rio de Janeiro's largest sewage treatment plants on Thursday to determine whether the facilities are actually treating sewage.
Police also collected documents in the surprise sting at least six plants. The material collected will help authorities decide whether to bring charges against Rio's state water and sewage utility, Cedae, for allegedly dumping raw or minimally treated sewage into the city's waterways, police investigator Marcelo Prudente said at a news conference.
The plants are located near polluted lagoons in western Rio that hug the Olympic Park and on the sewage-blighted Guanabara Bay, where Olympic sailing events are to be held. Water pollution has become a hot-button issue ahead of the Aug. 5-21 games in Rio since an Associated Press investigation revealed astronomical viral levels in the waters. Brazilian authorities had pledged to clean them up as part of the city's Olympic bid nearly nine years ago.
In a statement late Thursday, Cedae expressed ''surprise'' over the police operation and insisted its activities ''contribute to the improvement of the quality of life of the population of Rio de Janeiro, not causing pollution.'' It denied charging for services not provided.
Prudente suggested that the investigation into Cedae preceded the AP's July 2015 report. Rio was targeted because of the highly visible and smelly nature of the problem.
The probe grew out of the ''notorious public knowledge'' of sewage pollution problems in the two waterways, Prudente said, adding that testing of the samples collected at the plants would help ''measure the treatment the plants may or may not be doing.''
Prudente didn't provide many technical details about the testing, saying only that the results will likely take weeks. Depending on the results, both Cedae itself and its top executives could be handed pollution and larceny charges for charging consumers for sewage treatment services the utility doesn't actually provide, he said.
The police operation came as Rio Mayor Eduardo Paes inaugurated the revamped Gloria Marina on the Guanabara Bay where the Olympic sailing events will start.
The refurbishment costing the equivalent of $19 million includes new docks, as well as restaurants intended to draw the public to what had long been a private facility. Despite the upgrade, the black waters of the marina were still dotted with floating trash and stank of raw sewage at Thursday's event.
Paes said he has received promises from state authorities that a project aimed at staunching the flow of raw sewage into the marina would be finished by the end of next week.
Paes acknowledged the Guanabara Bay remains ''a challenge for the city.''
In a report released last July, The Associated Press published an independent analysis of water quality that showed high levels of viruses and, in some cases, bacteria from human sewage in all of Rio's Olympic and Paralympic water venues. They include the Guanabara Bay, the Rodrigo de Freitas Lagoon, where the rowing competitions are to be held, as well as Copacabana Beach, where the triathlon and marathon swimming events are to be staged.
A risk assessment based on the AP's study found that athletes who ingest just three teaspoons of water have a 99 percent chance of being infected by a virus, though that does not automatically mean they will fall ill. Whether they get sick depends upon a person's immune system and several other factors.
A major cleanup of the city's blighted waterways was meant to be among the games' most enduring legacies and was a key selling point for the city's victorious 2007 bid. The failure to even come close to fulfilling to those promises has become a major headache for authorities here.
''From a legacy perspective, I think this was a missed opportunity to reach the goal that was supposed to be achieve,'' Paes said, referring to Olympic bid pledges to drastically cut the amount of raw sewage flowing into the bay.
Paes dismissed fears that athletes' health could be compromised by competing in the blighted waters, saying the bay ''is not our worry for the Olympics.''
''With the contingency plan that we have, the bay is going to work well,'' he said.
Associated Press writer Mauricio Savarese in Rio contributed to this report.