INTERVIEW: How Nigerian government can tackle flooding – Expert

Annually, several farmlands, industries and houses are destroyed by flooding across regions of Nigeria.

Although northern Nigeria appears to be worst affected by recurring flooding, the southern part of the country is also grappling with the menace.

Maiduguri, the Borno State capital, appears to be the worst hit by flooding in Nigeria in 2024, with 38 people killed and over 390 people displaced, according to official figures.

In this interview with PREMIUM TIMES, Michael David, the Africa Regional Coordinator of Citizens Climate International, discusses the causes and solutions to the recurring flooding in Nigeria.

Excerpts:

PT: What do you think is the cause of flooding in Nigeria?

David: What is responsible for flooding all over the world at the moment is climate change. With the rising temperature, the atmosphere is able to hold a large volume of water, then it will release it at intervals. Ordinarily, rains that should fall under a period of one month, you find them dropping in one week or in even a day.

Scientifically, once the rate of infiltration of water into the soil is limited, or in other words, once the rate of rain exceeds the rate of infiltration, then there is run off and once there is run off from all the catchment areas, water begins to flow into our drainages, our natural drains and constructed waterways, and it will end up into flood plains and rivers overflowing their banks and leading to flooding.

In the South-east, flooding that happens around Ogbaru and Onitsha Axis in Anambra State, is simply as a result of the volume of water that comes from the Rivers Niger and Benue connecting to Lokoja. What is responsible for the outflow of water from River Niger is simply as a result of sedimentation. When there is runoff, it carries the topsoil along with it, and when the energy reduces, it begins to deposit even in the drainages and rivers. Most of our rivers are silted.

Also, when roads are constructed, drainages are made, and they collect water. The water is supposed to safely be discharged into a water channel, but in most cases, the roads are designed and the drainages are left in the open, and the next thing is that water overflow the drainages and the topsoil will be washed away. Because the soils in these areas are loose, the next heavy rain will lead to not even sheet but gully erosion across the axis.

Michael David, the Africa Regional Coordinator of Citizens Climate International

For the Maiduguri flood, it happened as a result of the failure of the dam. Basically, we can still attribute it to climate change. This is because the volume of water around North-east Nigeria has increased which is why we had flood waters flowing from Yobe, Jigawa, and Kano to Maiduguri.

So, the failure of maintenance of the Maiduguri dam contributed to the flooding. This should have been prevented.

Again, people do not take cognisance of the impact of allowing a water flood plain and our drainages are not properly designed, especially that of state roads. They are just one square metre which cannot accommodate the volume of water that comes in and then you find flood and all.

PT: So, what can be done to reverse this trend?

David: Another thing largely responsible for the flooding especially for the South-east is that the soil in the East: Enugu, Anambra are loose in nature. So, when you have that kind of loose soil, there must be protective covering over the soil.

If the trees are cut down, when rain comes, it begins to rush out.

So, in an area that is susceptible to erosion, there must be proper planning whether it is farming or urban development. The South-east governors must not leave their soils open all through the year because their soils are loose. There must be cover.

A vulnerability study must be carried out to find out where there is flood plain and natural water channels such that strict laws must be made that people should not build or block those water channels. Majorly, development in this part of Nigeria must and should be planned.

PT: Specifically, what should the federal government do to fight the incident of flooding?

David: The federal government should adopt a behavioural changes method. One key thing that the government is not doing is creating awareness. How much do people know about this? A lot of campaigns are happening at the federal level, but there is no step down into the states.

At the state level, we have the ministries of the environment and the Land Use Act has put land ownership in the hands of the governors, because the people are in the state.

So if the land is degraded as a result of erosion, what then is the economic impact to the governors? Public awareness and the use of religious institutions is a quick way of getting awareness down to the grassroots. So the state governments can partner with religious institutions because people like what comes from their places of worship.

Again, scientifically, what needs to be done is to carry out proper vulnerability assessment using Geographic Information System and mapping out places that flooding will take place and concentrate the campaigns on those areas.

A vulnerability study will detect the flood plain and natural flood channels such that strict laws must be made and people should not have to build or block the channels. In that case, you reduce the incidence of flooding.

PT: What behavioural changes should Nigerians adopt to help reduce the impact of flooding in the country?

David: It is abstaining from indiscriminate dumping of refuse in rivers. Apart from other causes of flooding, our people are responsible for dumping lots of refuse in rivers and drainages. For instance, River Niger has become a dumping ground for refuse. What people do is that they dump their refuse into the river, same for Rivers, Benue, Adamawa, Taraba and Lokoja. So the major dumping ground for Lokoja in Kogi State is River Niger.

The refuse reduces the volume of the river, so the capacity of the river is strained and then water moves down to the South-east. So, if our people stop dumping refuse in all the drainages, flooding will be reduced. In fact, the drainages are so small that they cannot carry the water, yet we block them.

But for us to get behavioural changes from the people, governments must invest in awareness creation. Finally, people should leave coastal areas to highlands for safety.

PT: Should the governments consider using legislation to fight human activities that encourage flooding?

David: I strongly believe that there are existing legislations in place against people dumping refuse in drainages, rivers and open areas. I think what is majorly needed is enforcement.