Indonesia: Disruptions due to flooding ongoing in parts of West Sumatra Province as of March 11

Flood-related disruptions are ongoing across West Sumatra Province as of March 11. Heavy rainfall has been ongoing in the region since March 7 and has caused rivers in the area to overflow. Authorities have confirmed 16 fatalities and seven missing in Pesisir Selatan Regency and three deaths in Padang Pariaman Regency. The floods have affected tens of thousands of people across the province.

Padang City is the worst impacted, with 35,299 people affected and 3,734 residents displaced. Floodwaters have begun to recede, and residents have since returned home. Around 37,265 houses across West Sumatra Province were affected, including 666 damaged houses.

Floodwaters are beginning to recede in some parts of the affected region as of March 11; however, the Indonesian Agency for Meteorology, Climatology, and Geophysics (BMKG) has forecast further periods of moderate-to-heavy rainfall accompanied by thunderstorms and strong winds across West Sumatra Province through at least March 12.

Further sustained heavy rainfall could trigger additional 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 located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rain has saturated the soil. Power outages could occur throughout the affected area.

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

The disruptive weather may cause delays and cancellations at regional airports. Flooding could block regional rail lines; freight and passenger train delays and cancellations are possible in areas with heavy rainfall and track blockages.

Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after conditions have improved - it could take days before any floodwaters recede and/or officials clear debris. Repair or reconstruction efforts may result in residual disruptions if there is severe damage to infrastructure.

Flooding could heighten the threat of disease outbreaks. Backflow from drains mixed with floodwaters can become trapped in open areas when inundations recede. These stagnant pools often become a breeding ground for mosquitoes and bacteria, increasing the incidence of insect- and water-borne diseases. Exposure to contaminated water from inundated industrial sites, sewer systems, and septic tanks also poses a significant health threat.