Swimming in poo: Fears of sewage leak in Olympic venue

Forget the heat, it’s Stinky Bay causing the most concern for our Olympic open water swimmers and triathletes, with concerns raised about the water quality in Tokyo Bay.

A foul odour has been reported at the swimming venue for triathletes and open water swimmers, raising concerns about elevated levels of the dangerous E-coli bacteria.

Heavy rain is forecast in Tokyo from July 27, which raises the risk of sewerage leakage into the bay.

Australian Triathlon team leader Justin Drew said Australia would continue to monitor the water quality in the lead-up to the first day of competition on Monday, July 26, with twice-daily tests at different sample points.

“We are confident in the measures put in place by (the Tokyo organising committee) including the installation of a triple filter screening system for this year as opposed to a single filter used last year for the Test Event,” Drew said.

“There are daily checks of water quality and water temperatures and TOCOG has plans in place to address any issues surrounding the water in the build up to competition days.

“We are a week out from the men’s race and those measures have been put in place. We will continue to monitor and be provided with regular daily checks on the water as well.

“These challenges are part of putting on races in a big city - we’re are just going to get on with preparing to compete.

“The Australian triathlon team has also prepared its own strategies.”

This week, local residents complained to Japanese media that the bay smelled like a toilet, fuelling concerns of elevated levels of the dangerous E-coli bacteria which is found in sewerage.

The swim leg of the triathlon and the marathon swim are being held at the Odaiba Marine Park, an urban beach in the heart of Tokyo, which has previously been the subject of complaints about water quality.

In 2019, the swim leg of the Paratriathlon World Cup was abandoned due to elevated levels of E-coli at the Odaiba Marine Park, which had reached twice the limit set by the International Triathlon Union.

Executive director of the American Swimming Coaches Association John Leonard also raised the issue back in 2019 and called for a change in venue due to elevated bacteria levels.

Tokyo organisers have ruled out any change of venue, saying the E-coli levels fall within “agreed limits’’ on most days.

It’s believed there have been private discussions among athletes concerned about the quality of the water in Tokyo Bay, after media reports about the rank smell.

The issue arises semi-regularly after periods of heavy rain, when Tokyo’s century-old sewer system becomes inundated with rainwater and flushes out into the river system which runs into Tokyo Bay.

The Tokyo municipal government had been working to improve the water quality ahead of the Olympic Games, depositing sand into the bay and installing triple-layered polyester screens.

Storage tanks were also built to capture floodwaters before they could be released alongside untreated sewerage into the bay.

The triathlon events are on July 26 and 27 and 31, while the marathon swim – a 10km endurance events – is held on August 4-5.

The problem is not without precedent - athletes in outdoor water events at the 2016 Rio de Janeiro Olympics in Brazil faced severe pollution in venues for rowing, sailing, canoeing, open-water swimming, and triathlon.