bid to host the Summer Olympics played down concerns over heat, with the proposal reading "With many days of mild and sunny weather, this period provides an ideal climate for athletes to perform at their best". However, Tokyo 2020 is expected to be the hottest Olympics ever, due to the urban heat island effect and climate change. In October 2019, the International Olympic Committee announced plans for moving the Olympic marathon and race walking to Sapporo, more than further north from Tokyo, in a bid to avoid heat. The Tokyo Metropolitan Government strongly opposed the IOC's decision, suggesting to move the marathon start time up one hour to 5:00 a.m., while Sapporo welcomed the IOC announcement. In October 2019, Japanese politician Shigefumi Matsuzawa wrote to IOC chief Thomas Bach to move the Olympic golf tournaments, scheduled to take place at Kasumigaseki Golf Club in Saitama Prefecture, about northwest of Tokyo, to a region with fewer heat problems. Concern over indoor temperatures has also been raised, since, for cost reduction, Tokyo's New National Stadium was built without an air conditioner, and the roof was constructed over the spectator seating only. In December 2019, the Asahi Shimbun reported that, due to the dangers of hyperthermia, 206 primary schools in 24 out of 50 wards in Tokyo Prefecture had given up their tickets to the Olympic and Paralympic games, which had been allocated to children by the government. Also, 101 additional schools told Asahi that they were considering giving up their tickets. According to the report, more than 70% of the private primary schools in Tokyo are planning to refrain from taking students to the Olympic and Paralympic games. Water quality and temperatures The sea off the Odaiba Marine Park in Tokyo Bay, the venue for the Olympic and Paralympic triathlons, has been reported to contain high levels of faecally-derived coliform bacteria. On 17 August 2019, the Paratriathlon World Cup scheduled at the venue was cancelled due to a high concentration of E. coli bacteria in the water. In the same year, some triathletes who competed in the world triathlon mixed-relay event at the park complained about the water's foul odor, saying that it "smelt like a lavatory". Scientists also urged the Olympic organizers to abandon the venue. In the same month, Ous Mellouli, Yumi Kida and other athletes who participated an Olympic open water test event in Odaiba Marine Park expressed their concerns over water temperature, odor, and clarity. Water temperature during the event was at , barely inside of acceptable range for official competition by FINA: . In December 2019, the USA Olympic Open Water Team head coach Catherine Kase and the American Swimming Coaches Association (ASCA) requested the open water venue to be moved out of Tokyo to safer waters. Saying that they "are not comfortable with the Odaiba venue", the U.S. swimmers and coaches called for a viable back-up plan for open-water venue, in case swimming in Tokyo Bay is not safe due to environmental factors, such as near danger levels of water temperatures (averaging in summer 2019) and water quality issues including E. coli bacteria and water transparency problems. In February 2020, swimmer Haley Anderson voiced her concerns for the compromised water quality (E. coli), unsafe water temperature (), and lack of plan B venue for the Tokyo Olympics, saying the swimmers "have spoken out and gone unheard so far". She also added that she is "not confident in FINA or the IOC to have the same concern for the athletes". Asbestos in Olympic venues Asbestos, a well-known health hazard that is prohibited from being used as a