Heavy seasonal rains have once again pounded much of Thailand, causing continued widespread flooding, particularly in the northeast and central regions.

Sunday's rains hit the northeastern province of Ubon Ratchathani, where almost 20,000 people have been moved into 85 temporary shelters as floodwaters overwhelmed more than 1,000 villages, the Department of Disaster Prevention and Mitigation reported.

The provincial Chamber of Commerce estimated 5 billion baht ($133 million) of economic damage from the flooding, as residents complained that they received little assistance for their plight, which saw floodwaters penetrate central urban areas.

More than 200,000 households in total in 54 provinces have been hit by floods over 10 days until Saturday, according to the disaster agency.

Dams reaching capacities 

Flooding is a seasonal problem in Thailand but this year it has been exacerbated by the remnants of Tropical Storm Noru, which swept through in the last week of September, and the southwest monsoon in the Andaman Sea and the Gulf of Thailand.

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Authorities recently warned that the capital, Bangkok, and other provinces along the Chao Phraya River could face severe threats as the volume of water flowing from upstream is more than can be contained in the river and dams.

As the major dams reach their capacities, the authorities are forced to release water, which in turn raises levels in rivers downstream.