FLOOD ALERT: LASG Raises Alarm Over Ogun  Dam Release 

The Lagos Government on Thursday alerted residents and property owners at the Ogun River Banks to be ready to relocate to higher grounds as the authorities of Ogun Osun River Basin Development Authority commence staggered release of water from Oyan Dam.

Addressing the media during a briefing at Alausa, Ikeja, the Commissioner for Environment and Water Resources, Mr. Tokunbo Wahab said Lagosians needed to be alerted on the commencement of the release of water to maintain the sanctity of the dam and its socio-economic implications for Lagos State.

He said it is crucial to understand that the dam’s annual operations are informed by real-time hydrological data, rainfall predictions from the Nigerian Meteorological Agency (NIMET) and flood outlooks from the Nigeria Hydrological Services Agency (NIHSA), adding that these sources guide the water release decisions to ensure both flood control and the integrity of the dam.

He said the State Government and the Ogun-Osun River Basin Development Authority (OORBDA) acknowledge the concerns raised regarding the release of water from the Dam and its impact on surrounding communities, particularly those along the Ogun River water channels extending into Lagos State.

Wahab said from its released guidelines, OORBDA operates the Dam in strict compliance with safety protocols to prevent structural damage and mitigate flood risks. He added that a detailed operational report by OORBDA states that the total water released from the dam this year, as of 12th October 2024, stands at 1,484.2 million cubic metres (mcm), which remains below the average synthesised annual flow volume of 1,770 mcm.

He stressed that although rainfalls across the Oyan River catchment area have been significant, with a cumulative 984.1 mm recorded this year, it remains lower than last year’s 1,540.8 mm and is within safe operational levels.

He further explained that the dam is equipped with four radial gates capable of releasing up to 2,271 cubic metres per second (m³/s) during peak periods and the current releases are measured at 208 m³/s, with only two gates opened at 12% capacity each, ensuring controlled and steady discharge.

Wahab added that 62.1% of the dam’s flood control capacity remains intact, with the Dam not under any imminent threat of releasing excess water beyond safe limits, noting that this has been made possible through the collaboration of the State with OORBDA.

He stressed that the State Government fully recognises the challenge faced by residents in affected communities which include Kara, Mile 12, Agiliti, Ikosi Ketu, Owode, Ajegunle, and Odo-Ogun as reported.

“However, I want to emphasise that while the flooding experienced in these areas has often been attributed solely to water released from the Oyan Dam, this is not entirely the case; In reality, the downstream section of the Ogun River is influenced by a complex network of over 52 tributaries, all of which converge and contribute to rising water levels in the affected areas”.

Wahab said these tributaries, combined with rain-induced runoff, significantly exacerbate the flood situation, stressing that this is a critical point to consider when addressing flood management strategies for this region.

He stated that to reduce the flood risks and ensure the free flow of water within the Ogun River system, Ogun-Osun River Basin Development Authority (OORBDA) recently flagged off the dredging of the Ogun River downstream from the Ikorodu to Isheri axis (Ajelogo, Owode-Elede, Ajegunle, and under deck-on-pile of Itowolo Bridge) for the water released on Friday, 13th September 2024.

The Commissioner said to effectively contain flooding; the Government is determined to maintain the long-established synergy and partnership with the Ogun-Oshun River Basin Development Authority, which has ensured control and monitoring of the steady and systematic release of water from Oyan Dam to prevent flooding of the downstream communities.

He said the State Government would continue to monitor the situation closely and collaborate with relevant Agencies and affected communities, to address humanitarian concerns, particularly for vulnerable groups like women, children, the elderly, and people living with disabilities.

Wahab also informed that the Emergency Flood Abatement Gang under the Drainage Maintenance Department of the Ministry have been consistently de-silting and working on secondary collectors and conduits to enable them to discharge efficiently and act as retention basins as part of statewide measures to prevent flooding.

He appealed to Lagosians to desist from indiscriminate dumping of refuse in unauthorised places, throwing pet bottles on the roads, clogging drains with silt or construction materials, erecting building structures within and around drainage Right of Ways/Setbacks, stopping discharging human waste into drains/canals which encourages high siltation and vegetal growth that easily clogs the canals as this act impedes the free flow of water.

He urged Lagosians to report cases of drainage blockages, and dumping of waste into canals and other unauthorised places to Resident Engineers’ offices statewide, saying Drainage Engineers with their telephone numbers will be made available in all 57 Local Government Areas and Local Council Development Areas to attend to their needs.

Present at the media briefing was the Permanent Secretary, Office of Environmental Services, Dr. Omobolaji Gaji and Permanent Secretary, Office of Drainage Services Engr. Mahamood Adegbite, as well as Directors in the Ministry.