The federal government has warned that flash flooding is likely to hit 15 states over the next seven days, and has urged people living in vulnerable communities to relocate before rising waters overwhelm them.

The Nigeria Hydrological Services Agency, NiHSA, issued the alert, numbered NFA-2026-262, for the period between September 19 and 25, 2026.

The states listed are Imo, Cross River, Ebonyi, Benue, Anambra, Akwa Ibom, Lagos, Rivers, Edo, Kogi, Taraba, Delta, Bayelsa, Enugu and Abia. The agency’s Director General and Chief Executive Officer, Umar Mohammed, said rising river levels were expected to cause flooding and that communities on floodplains should prepare to move to higher ground.

The advisory shows how much is at stake. In Imo State, seven local government areas are affected, with 958 communities, 1,022 schools, 553 healthcare facilities, 161 markets and 198 religious buildings exposed to the risk. Cross River appears even more vulnerable, with 2,471 communities, 703 schools, 344 healthcare facilities, 145 markets, 453 religious buildings and 854 hectares of farmland listed as exposed. Local government areas flagged in Cross River include Abi, Akamkpa, Akpabuyo, Biase, Calabar, Calabar South, Ikom and Obubra.

Mohammed said nine river monitoring stations were considered at risk and needed close attention, including Obubra, Itigidi and Epento on the Cross River. He called on state governments, local councils, emergency management agencies, traditional rulers and community leaders to take immediate precautionary steps, and asked affected state governments to urgently move residents in high risk areas to safer ground.

Residents were advised not to cross flooded roads, bridges or fast moving water, whether on foot or by vehicle. The agency also called for relief materials, safe drinking water, water treatment supplies and first aid items to be positioned ahead of time, and urged communities to identify safe shelters for possible temporary evacuation. People were further advised to clear blocked drainage channels and river outlets where it is safe to do so, and to avoid building or staying in floodplain areas. NiHSA said it would keep monitoring river levels and update the public as conditions change.