Brazil: Disruptions ongoing as flooding continues to impact parts of southern regions as of May 6 /update 4

As of May 6, the death toll continues to rise as flooding brought on by severe weather continues to impact southern Brazil. Heavy rainfall since April 29 has resulted in widespread flooding, telecommunication disruptions, and landslides in Parana, Rio Grande do Sul, and Santa Catarina states; Rio Grande do Sul is the worst affected, especially Porto Alegre. Rescue efforts are continuing across the city. Officials have confirmed that the severe weather has killed at least 76 people and injured 74 others, with at least 103 people missing across the Rio Grande do Sul. Additionally, over 800,000 people have been affected, with almost 115,000 displaced, and the governor of Rio Grande do Sul, Eduardo Leite, has declared a state of calamity for 180 days.

A dam of the 14 de Julho hydroelectric power plant in Cotipora Municipality, between Cotipora and Bento Goncalves cities, has partially collapsed and will likely suffer further damage. The Blang, Dal Bo, and Santa Lucia dams also risk rupturing. The Taquari and Cai rivers are also in danger of flooding, and authorities have advised residents in the vicinity and downstream of the rivers and dams to evacuate the area. Almost 140 sections across 60 highways are totally or partially closed. Damaged or flooded roads or bridges have isolated several towns. Extensive power outages and water are affecting several hundred thousand people across the region. Around 48 cities also do not have telecommunications or internet services. Authorities have suspended classes statewide through May 7. As of May 4, officials have suspended operations at Salgado Filho International Airport (POA) in Porto Alegre until further notice.

As of May 6, Brazil's National Institute of Meteorology (INMET) has issued red heavy rainfall storm warning (the highest on the three-tier scale) for far southeast Rio Grand do Sul, orange heavy rainfall and storm warnings (the second highest level on a three-tier scale) across parts of southern Rio Grande do Sul, including Southwest Rio-grandense, Southeast Rio-grandense, and yellow storm warnings are in place across parts of Southwest Rio-grandense, Southeast Rio-grandense, Western Center Rio-grandense. Officials could update and extend the coverage of the relevant weather alerts over the coming days.

Sustained heavy rainfall could trigger further flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides remain possible in hilly or mountainous areas, especially where heavy rain has saturated the soil. Power outages and disruptions to telecommunications services will likely occur where significant flooding, landslides, or strong winds impact utility networks.

Floodwaters and debris flows could render some bridges, rail networks, or roadways impassable, impacting overland travel in affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.

Severe weather could further trigger intermittent flight delays and cancellations at regional airports. Authorities will likely temporarily suspend port operations or close beach fronts along the Atlantic coast if strong winds trigger hazardous sea conditions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are probable in areas with heavy rainfall and track inundation. Localized business disruptions will likely occur in low-lying areas.