West Africa: Widespread disruptions due to flooding ongoing across parts of Mali, Niger, and Nigeria as of Sept. 3

Widespread disruptions due to flooding are ongoing across parts of Mali, Niger, and Nigeria as of Sept. 3. Heavy rainfall has occurred across the region in recent days and weeks amid the ongoing rainy season and has triggered severe flooding in many areas. Authorities in Nigeria have reported at least 170 flood-related fatalities since Aug. 20, with northern regions the worst affected. More than 500,000 people have been affected across 28 of the country's 36 states. More than 200,000 people have been displaced and over 75,000 homes have been damaged.

Authorities in Niger reported 15 fatalities following torrential rainfall in Maradi Aug. 30, bringing the total number of fatalities across the country since the rainy season began in June to 217. More than 350,000 people have been displaced and the floods have impacted numerous roads, destroyed agricultural areas, and killed thousands of livestock. Authorities in Mali declared a nationwide state of emergency Aug. 23 after flooding caused at least 30 fatalities across the country. Nearly 50,000 people have been affected or displaced across the country, with the capital, Bamako, and the northern region of Gao amongst the worst affected areas. The floods are also causing increasing concerns regarding water- and vector-borne diseases across the region.

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 the soil has become saturated by heavy rainfall.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are likely where significant flooding or landslides impact utility networks.

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 cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.

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.