Tokyo Governor Yuriko Koike has pledged to clean up the waters at the city's beaches following the cancelation of a triathlon test event for the 2020 Olympics and Paralympics last week.
The swimming portion of the event, scheduled for August 17 at Odaiba Marine Park, was canceled due to poor water quality.
The park is the intended venue for the swimming leg of the triathlon for the Tokyo Games. But a test of the water there turned up over twice the level of E. coli bacteria allowed by the International Triathlon Union.
Organizers blamed weather conditions in the area just before the event. They said heavy rains made it impossible to treat all the wastewater and runoff that poured into the venue.
Koike told reporters on Friday that the Metropolitan Government plans to replace the single-layer underwater screen with a triple-layer one for next year's Games.
She said her government will work with the Tokyo Games organizing committee to improve water quality so that the athletes can perform at the highest level at the Olympics and Paralympics.