A local bathing facility has been set up free of charge for residents in Mabicho, but those without cars can not make the journey there, and many continue to go without being able to bathe.
Asked if he knew he lived in a designated risk area, Kenji Ishii, a 57-year-old resident of Mabi district, said: "I'm afraid I did not know that very well".
More than 20,000 people were killed or went missing during the Fukushima disaster, when a 9.0-magnitude quake hit Japan, triggering a tsunami and nuclear meltdown at the Fukushima nuclear plant. Thousands of homes were without clean water and electricity in the city of Hiroshima and other hard-hit areas.
About two million people have evacuated the region after rivers burst their banks.
A man walks past a devastated street during floods in Saka, Hiroshima prefecture on July 8, 2018.
"We are checking every single house to see if there are people still trapped inside them", said an official with the local Okayama prefecture government, the AFP reported.
Residents sheltering at the Yano school were provided with water, blankets and cellphone chargers.
In the town of Saka, Eiichi Tsuiki opted to stay in his home, and survived only by moving to the top floor as flood waters rose, washing cars away outside.
Although the government has yet to get a firm handle on the extent of the damage, some 347 homes were totally or partially destroyed and 9,868 homes were flooded as of Tuesday morning, according to the Fire and Disaster Management Agency.
According to the West Nippon Expressway Company, at least seven expressway sections including those in Hiroshima and Okayama prefectures remain severely damaged with little chance of fix anytime soon.
Torrential rains unleashed floods and landslides in the west of the country last week, prompting Prime Minister Shinzo Abe to cancel an overseas trip to cope with the disaster, which at one point forced several million from their homes.
Japanese officials said more than 73,000 emergency workers and troops were involved in search and rescue efforts.
Although evacuation orders were scaled back from the weekend, almost 2 million people still face orders or advice to keep away from homes, fire and disaster officials said.
The assessment of casualties has been hard because of the widespread area affected.
Residents look at a flooded road in Hiroshima on July 7, 2018.
Parts of southwestern Japan had up to 10 centimeters of rain per hour, the highest level in decades.
The intensifying heat was also contributing to unsettled weather conditions likely to lead to thunderstorms later on Wednesday, with authorities warning new landslides could easily be set off on mountainsides saturated with water.