‘Improper town planning worsening perennial flooding in Port Harcourt’
An expert in applied meteorology and environmental management at the Rivers State University, Port Harcourt, Prof. Akuro Gobo, told KELVIN EBIRI, that poor urban and regional planning gave birth to the perennial flooding that is plaguing Port Harcourt and other parts of the state.
Port Harcourt and its environs have become susceptible to flooding in recent times. What is the cause of this?
The causes of flooding could be classified in two- natural and man-made causes. In as much as we may not be able to control nature and the forces that dictate the pattern of rainfall, the man-made causes, which are the ones that we can control are even the ones that are causing more problems for us. We are really blessed in this environment because we know the onset and period of cessation of the rains, as well as, the onset and cessation of the dry seasons. Apart from two pronounced seasons- rainy and dry seasons, we are further blessed to know that July and September (at least for this environment), is when rainfall peaks. So, our problem ordinarily would have been reduced because we know the pattern of rainfall, but we are not proactive and that is our challenge.
We are not proactive in the sense that we know that we would have the heaviest rainfall in July and September, so what stops us from desilting the creeks and the necessary channels before the rains? We also have this attitudinal problem of dumping refuse in the drains thereby blocking them. What we have here most times is what we call flash floods, which are caused by heavy downpour for a very limited time. Ordinarily, after a heavy downpour, we should necessarily not have any problems if there are proper drainages because we are surrounded by rivers, creeks and different discharge channels.
What is your assessment of the drainage system in Port Harcourt and its environs?
A good drainage must slope, be deep and must have a discharge point. If a drainage is without these and sundry features, especially a discharge point, then it is not a good drainage and that is one of the major challenges that we have. Yes, the roads that the state government is constructing are good, but they don’t discharge to the creeks and rivers that surround us. I will give you a typical example.
If you take Mile One for instance, what is the distance between Mile One market and Abonnema Wharf? Why is Mile One flooded at the slightest rainfall? Floodwater from Mile One could be channelled to Ntanwogba Creek, which is a very short distance from there. If you want to solve the problem, you must construct the drainage in such a way that the water discharges into the creek because we are blessed in Rivers State, where we have tidal flows (ebb tide and flow tide) when the water rises, but we are not utilising the creeks and rivers surrounding us. This particular administration is constructing roads and drainages, but the drainages must discharge into the channels.
I was privileged to be in The Netherlands, if you are landing at their airport, it is as though you were landing on the sea because it is situated on a low land. But how did they overcome the challenge posed by the rains? They ensured that all their drainages must have discharge points.
I was privileged also to do my Ph.D work on flooding in the Niger Delta and that led me to travel to all states in the region, and it is only in Calabar, Cross River State that I was impressed with their drainage system. Their drainages are deep, wide, sloppy and they discharge into the creeks. In Calabar, you cannot jump across a drainage because they are wide and deep.
All former wetlands in Port Harcourt and its environs have been built up. Hasn’t urbanisation contributed to the perennial flooding in the city?
Everybody wants to stay in main Port Harcourt and the resultant effect is that even areas that were designated as recreational areas are being converted to residential areas. Look at the creeks in the old Government Reservation Area (GRA), people are extending their buildings into the creeks. Do you know that even on Ntanwogba Creek somebody is building right there? When I saw that happening I had to go and inquire why that was happening, and the developer told me that he was allocated that plot by the ministry and that he has a certificate of occupancy.
There has to be checks and balances during the process of urbanization because most of these people who build on natural waterways have approval from appropriate state ministries. In other words, there must be synergy between the ministries of works, environment, as well as, lands and survey so that these things can be checked. Even if somebody goes to acquire a plot of land, the Ministry of Environment should be able to go and inspect the place; while the ministries of works, lands and survey, as well as, that of environment should also check before buildings are approved or lands allocated because most of the discharge channels and the waterways have been built up.
In Old GRA for example, how many people get approvals for what they are building? Even when someone gets a land behind the creek, he projects his building into the creek.
I stay in Old GRA and I know that most buildings behind the Ntanwogba Creek are distorting the flow of creeks and rivers so, relevant ministries must work together to address this challenge. Specifically, the government should always go in and ensure that there are no breaches before construction work starts.
Before now, no construction work would take place without an authentic survey plan of the area being referred to so that every ones knows places that are reserved for recreational and residential purposes, but these days, buildings are being erected indiscriminately. Ordinarily, government should build roads with network of drainages and even create artificial lakes so that when there is downpour the rainwater would be channeled to the right place.
In the past, a lot of efforts went into town planning activities. For instance, before building, data of 30 to 50 and even 100 years would be analysed in order to know the volume of water that comes into a particular environment, same would be done for rainfall pattern before roads are constructed. By the time all these things are put into consideration, solution to a lot of problems that would arise in future would have been found, but these days, money for such studies are considered a waste.
What is the economic implication of perennial flooding?
One of the biggest problems is that most of the areas that were not flooding would begin to experience flood, and once that happens, the economic implications becomes huge. Creeks that were hitherto flowing would cease to and there would be increase in cases of malaria fever because mosquitoes would have fine breeding ground. Once this happens, a major health challenge has been thrown up.
In terms of agriculture, Port Harcourt may not be that much affected because we don’t have much land, but farmlands are going to be destroyed in other parts of the state that are facing similar challenges. This sometimes lead to premature harvest of crops.
Residential and businesses premises would definitely be destroyed. When this happens, a lot of people are not only displaced, but certificates are also lost in the process.
Do you think any lesson has been learnt from the 2012 flood that ravaged communities in Rivers and Bayelsa states?
No, we have not learnt anything. Coincidentally, I did the post-impact assessment for the UNDP. The flood affected Ahoada East, Ahoada West, Abua-Odua and Ogba/Egbema/Ndoni local councils of Rivers State. That flooding was aggravated by the opening of the Lado dam in Cameroon, and the water flowed down to affect these council areas. But we have not learnt anything.
How can the issue of flooding be best tackled?
First, there must be synergy among professionals, as well as, the various government ministries that their functions relate to urban development. When I talk about synergy among professionals, I am an applied meteorologist and I cannot do this alone. You must need surveyors, town planners and others to tackle the problem of flooding. Before, when roads were to be constructed, the contractor would call various professionals such as meteorologists, town planners, urban and regional planners, surveyors and socio-economists to assess the impact of the project on human beings and then proffer solutions. But these days, immediately a contractor is awarded a contract, especially in this political era, he sets out to execute same not minding its impact on the human component of the society.
For instance, on the Obiri Ikwerre-Airport Road and some parts of East-West Road, people still experience flooding, and the main problem there is that there were no real feasibility studies done. All they did was to first construct and raise the road, and now when it rains, the rainwater must find a lower level where it will be discharged. The ideal thing that should have been done should have been, during the construction work, side drainages that are connected to the creeks or rivers should have been created. If that were to be in place, what is happening now would not have happened. But our interest at that time was to build the road and we forgot that there were communities at the lower level. Definitely, when it rains, there will be spillover and that is what those in these areas are suffering, and until proper drainages are constructed, there is nothing that can be done. If there are no drainages that are discharged, annually these areas would be waterlogged until a solution to the problem is found, and the simplest solution is to construct drainages. Government can even provide artificial channels, where the water would drain into because those are low land areas.
Why are experts like meteorologists who can predict the pattern of rainfall ignored?
Let me give credit to the Nigerian Meteorological Agency (NiMET), which has been predicting rainfall pattern, even though the people are not utilising it. How many people would today go to Lagos to pickup rainfall data and analyse to see the pattern before designing, or to guard against flooding? No one is doing that, but in proper drainage designs, you must use rainfall data for about 30 to 50 years for analysis so that you can see the reoccurrence period; see what we call return periods, extreme values so that you can predict fairly accurately. But today, in engineering design they don’t take this painstaking process any longer. Part of our problem is that people just want to see that a road has been constructed, or a structure has been put in place, all without putting the basic things in place. This is part of our problem. I insist there should be synergy because in designing flood control structures, you need rainfall predictions; you need to know the quantity of rainfall that comes into the system; the intensity, the duration, the runoff values so that things can be done in the right manner and the appropriate information handed over to the civil engineer.
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