The isolated sub-districts were Helumo, Tomini, and Posigadan, Raditya Jati, spokesman of the National Disaster Mitigation Agency (BNPB), noted in a statement on Monday.
At least 7,046 families, comprising 22,655 people, were affected by the flash floods in seven sub-districts in South Bolaang Mongondow.
The flooding also caused severe damage to 64 homes, five bridges, and roads.
In the sub-districts of Bolaang Uki District, 2,978 households or 9,715 residents were affected, while 225 households or 861 residents in Helumo, 62 households or 250 residents in Tomini, 154 families or 636 residents in Posigadan, 1749 families or 5980 residents in Pinolosian, 925 families or 1,729 residents in Central Pinolosian, and 953 households comprising 3,494 people in East Pinolosian.
Incessant downpours triggered major flooding on Friday, causing several rivers -- Bolangaso River, Toluaya River, Salongo River, Nunuka River, Mongolidia River, and Milangodaa River -- to overflow their banks and submerged residential areas in South Bolaang Mongondow.
The floodwaters subsided on Monday, but rains were forecast to continue to fall in the district in the coming days.
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