The Nigeria Hydrological Services Agency (NIHSA) has issued a high flood risk advisory for Delta State, warning that 343 communities across 13 local government areas could experience flooding between July 21 and July 27 due to rising upstream river flows.
The advisory, issued on Tuesday under Alert No. NFA-2026-200-DEL, classified the situation as “High Flood Risk”, urging residents in vulnerable communities to relocate immediately from flood-prone areas and adhere strictly to safety measures to avert loss of lives and property.
According to NIHSA, although river gauge stations within Delta State are currently reporting normal water levels, the threat is being driven by increased upstream river discharge, which is expected to inundate downstream communities during the validity period of the forecast.
The agency identified 13 local government areas as being at risk, including Ethiope West, Isoko South, Isoko North, Ndokwa West, Okpe, Sapele, and Udu, among others.
The forecast further revealed the scale of the potential impact, with 343 communities expected to be affected if the flood materialises.
Beyond residential areas, the agency warned that key public infrastructure and institutions could also be hit. These include 1,110 schools, 272 health facilities, 57 markets, 552 religious centres, and four other critical sites, highlighting the potentially far-reaching humanitarian and socio-economic consequences of the anticipated flooding.
In a brief summary accompanying the advisory, NIHSA explained that the projected flooding is primarily a consequence of upstream river flow rather than local rainfall or abnormal river gauge readings within Delta State.
The agency stated that water levels at Saminaka gauge on the Karami River have exceeded advisory thresholds, resulting in a forecast flood footprint extending into downstream communities and public facilities across Delta.
To minimise the impact of the anticipated flooding, NIHSA advised residents living within floodplains to immediately move people, livestock and valuable belongings to safer, elevated locations.
The agency also urged members of the public to closely monitor its flood bulletins for updated information on river levels and changing flood conditions.
It further called on emergency managers and community leaders to pre-position relief materials, water-treatment supplies and first-aid items while identifying safe shelters for displaced persons ahead of any flooding.
As part of its preparedness measures, NIHSA encouraged the mobilisation of community-based early warning volunteers to help disseminate timely information and coordinate local response efforts.
Residents were also warned against attempting to cross flooded roads, bridges or fast-flowing water either on foot or in vehicles, stressing that such actions significantly increase the risk of drowning.
In addition, the agency advised communities to clear blocked drainage channels and river mouths where possible, while cautioning against building or residing within flood-prone areas.
The advisory comes amid heightened concerns over seasonal flooding across Nigeria, with authorities intensifying early warning efforts to reduce disaster risks and improve preparedness in vulnerable states before peak flood periods.
NIHSA issues flood alert for 17 states
Meanwhile, NIHSA has similarly issued a seven-day flood advisory, warning of a medium flood risk in 17 states between July 21 and July 27.
The agency said the alert followed rising water levels at key river monitoring stations, increasing the likelihood of localised flooding along river channels and floodplains.
NIHSA Director-General, Umar Mohammed, disclosed this in National Flood Advisory (Alert No. NFA-2026-200) issued on Tuesday.
He said the affected states are Adamawa, Bauchi, Benue, Borno, Edo, Gombe, Imo, Jigawa, Kaduna, Kano, Kebbi, Nasarawa, Niger, Plateau, Taraba, Yobe and Zamfara.
According to Mohammed, river levels at Saminara on the Karam River, Waya Dam Site on the Waya River and Amber on the Amber River had exceeded watch and warning thresholds.
He said 16 gauging stations nationwide were recording elevated river stages, placing nearby communities at risk of localised flooding.
Mohammed urged state governments, local authorities and residents of flood-prone communities to take precautionary measures immediately.
NIHSA said Bauchi had the highest exposure, with 1,841 communities, 145 schools, 101 health facilities and eight markets identified as vulnerable.
The agency also identified vulnerable communities and public facilities in Edo, Imo, Kaduna, Plateau and Benue states.
Mohammed urged the National Emergency Management Agency (NEMA), State Emergency Management Agencies (SEMAs), local governments and community leaders to activate emergency response plans.
He recommended relocating residents, livestock and valuables from floodplains to safer locations.
He also advised emergency agencies to pre-position food, medical supplies and water treatment materials in areas likely to be affected.
The NIHSA boss called for community mobilisation through early warning volunteers and local communication channels to ensure timely dissemination of flood alerts.
He cautioned residents against walking, driving or riding through flooded roads, bridges and fast-flowing waterways.
Mohammed further urged authorities to clear blocked drains, culverts and waterways to improve water flow and reduce flooding.
He advised the public and relevant agencies to monitor daily flood updates and advisories issued by NIHSA.