Oyan Dam: Lagos asks residents to relocate

Lagos State yesterday alerted residents and property owners at the Ogun River Banks to be ready to relocate to higher grounds as the Ogun Osun River Basin Development Authorities begin staggered release of water from Oyan Dam.

Addressing the media yesterday, the Commissioner for Environment and Water Resources, Tokunbo Wahab, said Lagosians needed to be alerted on the commencement of release of water to maintain the sanctity of the dam and its socio-economic implications for Lagos.

He said the dam’s annual operations are informed by real-time hydrological data, rainfall predictions from Nigerian Meteorological Agency and flood outlooks from Nigeria Hydrological Services Agency that guide the water release decisions to ensure both flood control and the dam’s integrity.

He added that total water released from the dam this year, as of October 12, stands at 1,484.2 million cubic meters (mcm), which is below average synthesized 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, saying it remains lower than last year’s 1,540.8 mm and is within safe operational levels.

Wahab explained that the dam is equipped with four radial gates capable of releasing up to 2,271 cubic meters 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.

He 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 saying this has been made possible through the collaboration of the State with OORBDA.

He said the State Government fully recognizes 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” he said.

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

He stated that in an effort 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.

Wahab stressed that some right-of-ways along the catchment areas were protected and restored, saying that the dredging project was a proactive measure to deepen the river channel and increase its capacity to convey water, thereby reducing the likelihood of flooding during periods of high inflow.

The Commissioner said to effectively contain flooding the Government is determined to maintain the long-established synergy and partnership with 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.

Tokunbo Wahab also informed that the Emergency Flood Abatement Gang under Drainage Maintenance Department of the Ministry have been consistently de-silting and working on secondary collectors and conduits, to enable them 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 unauthorized places, throwing pet bottles on the roads, clogging of drains with silt or construction materials, erecting building structures within and around drainage Right of Ways/setbacks, stop discharging human waste into drains/canals which encourages high siltation and vegetal growth that easily clogs the canals as these act impedes the free flow of water.

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

In his words: “I wish to appeal once again to our people to support our efforts by complementing the State Government through regular clearing of drains in their frontages to ensure free-flow of storm water as well as to desist from dumping of refuse into drainage channels and roads.

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.