From Our Housing Stand (128)
The World is endangered by Numerous environmental issues. Flooding is considered the most damaging natural disaster in the world. Flooding is defined as excess water running onto dry ground , such as when rainfall exceeds the soil’s absorption capacity, resulting in substantial environmental repercussions.
Floods in Maiduguri,northern Nigeria have killed more 30 people and more than 80% of the animals in a large zoo housing wildlife from lions and crocodiles to buffalo and ostriches, the facility has said. “Some deadly animals have been washed away into our communities, like crocodiles and snakes,” the Sanda Kyarimi Park zoo added in a statement on the floods in the northern Borno state, urging residents to take precautions.
Borno, the Maiduguri state capital has in recent times been ravaged by a devastating Flood, which began when a dam overflowed after heavy rains, uprooting thousands of people.
According to the UN, as of September 10, over 414,000 people have been affected, 58 people have been injured, and at least 37 people have been killed. Approximately 40,000 people have been registered at three internally displaced persons (IDPs) camps, originally housing those fleeing violence. As assessments continue, the number of affected individuals is expected to increase.
According to environmental experts, ‘the rate of flood occurrence in recent times has been unparalleled, with 70 million people globally vulnerable to flooding every year, and more than 800 million living in flood prone areas’. Another school of thought says,’1.47 billion individuals, or 19% of the world population, are directly exposed to considerable risks during 1-in-100 year flood occurrences’. It’s been established that, flooding results from climate change, excessive precipitation, building on waterways, sea-level rise, soil moisture regime, dam operations, especially along borders, uncontrolled rapid population growth, inadequate preparedness, and lack of political will .
Flooding has both natural and human causes, experts have also identified excessive levels of precipitation as the main natural cause of flooding, caused by climate change, they link flood occurrence to maximum level of soil moisture rather than maximum precipitation.
Nigeria is one of the most flood-prone countries in west Africa. Many areas experience annual flooding. This happens during heavy rainfall and one of the reasons is poor drainage systems.
The country therefore needs to make improvements. On our stand today, we believe there are several ways in which the Flood in Maiduguri can be prevented in future. The key interventions needed are:
• understanding the impact of climate change on rainfall extremes and water resources
• investing in a functional weather forecast system
• addressing the problem of poor drainage.
These actions are necessary to build resilience to floods. The Nigeria Meteorological Agency and the Nigeria Hydrological Services Agency had predicted severe flooding this year. And recent devastating flooding incidents are still fresh in the minds of Nigerians.
Flooding in Nigeria
Flash floods are considered the deadliest hazards related to extreme weather. Nigeria is increasingly prone to them.The collapse of the Alau dam on the Ngadda river in Borno State on Tuesday caused some of the state’s worst flooding since the same dam collapsed 30 years ago, and prompted residents to flee their homes.
The state government said on Wednesday that the dam was at capacity due to unusually high rains. Officials expected the death toll to rise. The current flooding comes nearly two years after Nigeria’s worst flooding in a decade killed more than 600 people across the country. Ezekiel Manzo, spokesman of the National Emergency Management Agency, on Wednesday put the death toll at 30. “One million people have been affected so far,” said an aide for Borno State Governor Babagana Zulum, adding that as efforts to document displaced people begin, that number could rise to nearly two million.
This is expected to get worse as a result of global warming, according to a recent scientific study by the World Weather Attribution scientific team. The atmospheric rivers linked to the recent heavy rainfall over the region are associated with a warmer north Atlantic and Mediterranean. The warming is connected with sea surface temperature anomalies in the tropical Pacific Ocean, described as Trans-Atlantic-Pacific Ocean Dipole.
The second set of drivers is geographical. For example low-land and coastal areas are flood risk areas because of rising river levels. Previous flood disasters have shown that these areas are disaster prone. To a certain extent flooding in Nigeria has been made worse by the poor management of drainage systems. The combination of heavy rains and nonexistent or poor drainage system increases the likelihood of flash floods in cities. Adding to the problem are poor waste disposal, poor urban planning, tarmacking of urban roads and construction of drainage systems without climate adaptation in mind.
The impact Of Flooding
The most important consequences are socio-economic, health-related, ecological and cultural. Socio-economic consequences include the loss of lives, emotional and psychological distress, and destruction of property, social amenities and infrastructure worth billions of naira.
Another effect of flooding is the loss of economically productive time, which may cost the economy billions of naira daily. Flooding has also been linked to an increase in the number of people contracting water-borne diseases such as cholera. Due to poor sanitation infrastructure, floods can distribute faecally contaminated water. Widespread outbreaks of cholera in Nigeria in 2010 were linked to exposure to contaminated water after flooding.
Another consequence is ecological and environmental. A study has shown that flooding tends to increase the spread of chemical pollutants in soils on floodplains. Flooding also destroys wildlife habitats, depletes fishery stock and alters biodiversity and ecosystem functions critical to socio-economic development.
Mitigating Effects of Flooding
Nigeria can address the flooding menace and minimise its effect through a multi-pronged approach. First, a combination of hard infrastructural solutions and ecosystem-based adaptation should be pursued. There’s no way to influence rainfall variability, especially in the short term. But green engineering can help protect humans and the environment.
There are two strategies that Nigeria can easily use. They are proper dam management and tree planting.
These initiatives will reduce the speed of water flow and reduce the impact of floods. Another easy intervention is the process of risk mapping, assessment and planning for floods. This informs how resources should be distributed and how to reduce risk. It has been successful in countries such as Romania and Bulgaria.
Weather Forecasting.
Forecasting is a complex process that is continually being improved as artificial intelligence and machine learning are incorporated into the prediction technologies. Capacity building is required to improve the reliability of forecasting in the country. Both the Nigeria Hydrological Services Agency and the Nigerian Meteorology Agency provide timely precipitation forecasts for water-related disaster management.
The World Meteorological Organisation has supported forecasting services in west Africa through its Severe Weather Forecasting Demonstration Project. The project would be more beneficial if it operated in all meteorological centres across the country. For weather forecasting to deliver quality data, there is a need to continuously invest in equipment and review performance. For instance, the NigeriaSat-2 was built to provide high-resolution imagery of the Earth’s surface but it’s past its design life.
Efficient Drainage Systems
Drainage systems can be developed and improved by channels or ditches, and piping that directs excess rainwater and sewage to a point of disposal. Sustainable urban drainage systems are becoming common given their multiple benefits such as reducing the effects of pollution. Nigeria also needs to strengthen its regulatory, governance and institutional capacity in the area of spatial planning, regional cooperation on transboundary water resources management, emergency response time, flood prediction, and enforcement of environmental and spatial planning laws.Building on flood plains must be avoided at all costs.
Awareness raising, education and disaster risk communication and messaging need to be strengthened to minimise flooding effects in Nigeria. Lastly, financing has stood out as a challenge. The Nigerian Government needs to make good use of the climate change loss and damage fund. Access to the funding depends on having systems for data collection, recording and reporting of loss and damage finance needs.
Conclusively, the tragic flooding that ravaged Maiduguri brings to the fore the need for vigilance and installation of early warning systems across the country. Storms will always come but it is important for the government to put in place mitigation and adaptation strategies. These can be achieved through early information flow to the communities. Those in charge of dams usually know from calibration when the water is getting to levels that could cause it to either overflow or burst. This is the reason for controlled release of water from dams after people likely to be affected have been alerted. With more vigilance, the burst of the Alau Dam that released most of the water could have been prevented. But we understand that government agencies charged with the responsibility of monitoring the weather and warning residents about impending storms are poorly funded and ill-equipped. And regrettably, authorities in Borno State were not proactive, because they issued the flood alert on the day the dam collapsed. Borno State government warning came too late. They should have known and done better, because this is not the first time the dam would collapse. In 1994, this same Alau Dam collapsed, leading to widespread devastation. Indeed, nearly half of Maiduguri was submerged.
