THE flood menace being experienced in some states especially in northern, middle belt and parts of Delta regions of Nigeria does not come as a surprise to most Nigerians. That it has become some sort of perennial occurrence is also not news. In fact, most Nigerians are now aware that it is not totally a natural disaster but also an artificially-induced problem created by mankind and which can extensively be controlled by same.
This flood menace occurs whenever Cameroun releases water from its Lagdo dam. Lagdo dam which was built in 1982 about 50 kilometres of Garoua, by the Lagdo Lake.. The hydroelectric Lagdo dam, at present being managed by AES SONEL, a unit of U.S.-based AES Corp., has the primary responsibility of supplying electricity to the northern part of Cameroun. Cameroun in the past experienced inadequate rainfall which, predictably, has been negatively affecting the production capacity of hydroelectricity in the Lagdo dam.
This makes the management of the dam retain as much water as possible in its reservoirs. With the recent climate changes, rainfall has increased and more water can now be stored to boost hydroelectric power generation. Conversely, more rain also means more doom, as excess water stored in the dam will become catastrophic whenever the gates of the dam are open to avoid over filling the dam.
As a result of the highland terrain of the land mass surrounding the Lagdo lake such as Benoue, Tchollire, BoubaNdjida and Garoua, water released from Lagdo dam is naturally unable to find its path within Cameroun to the Atlantic ocean through water bodies in that country. This is unlike other lakes in Cameroun such as Mbakaov, Lake Bankim and Lake Bamendjing which all have tributaries within Cameroun to the Atlantic Ocean.
The water released from Lagdo dams flows directly into River Benue from these highlands of Cameroun. Since River Benue is naturally steep, this consequentially leaves the lowland planes Adamawa, Plateau, Benue, Kogi, Delta and some other States flooded with the high volume of water dispensed from Lagdo dam whenever the authorities of the dam deem it fit to release the water so as to preserve the dam. Homes, farmlands, livestock, means and sources of livelihood of thousands of Nigerians are directly affected by these floods.
Consequently, the means of livelihood and cost of living of millions of Nigerians in other parts of the country are indirectly affected especially in transportation, food stock, and investments, resulting in panic and ill health. Other adverse effects of the floods are the undermining of bridge structures and buildings, concentrate garbage, debris, toxic pollutants, wildlife, gas and electric service disruption. It also causes erosion and developments of new river channels.
Floods also increase insurance rates and cause the government to re-direct funds for infrastructure development to relief efforts. It may also increase corruption from misuse of relief funds and cause job losses through business disruption although there may be job boost subsequently in construction industry.
Dams are not built to be a curse. They are artificial blessings created by mankind. Dams are usually built close to rivers, lakes and other appropriate sources of water, basically to preserve water for people, generate hydroelectric power (HEP) and in some cases to control flood.
Cameroun will always want to keep Lagdo Dam full in order to generate electricity. On the contrary, Nigerians along the River Benue plain which is lowland when compared to the high land plains of Cameroun will want the Lagdo dam empty.
It is, therefore, the responsibility of the governments of Nigeria and Cameroun to proactively foster an immediate solution to this menace and to protect not just the lives and properties of Nigerians but ultimately their means of livelihood. In fairness, the governments of both countries, have discussed the menace of Lagdo dam flooding.
Resolutions reached include the notification to Nigerian authorities of the dam opening dates in order to ensure adequate emergency planning. Others include warning from Nigerian authorities to its citizens, evacuation, emergency management and compensation when applicable. At this stage of Nigeria’s national development, our government should not continually fold its arms and resort to merely emergency responses, warnings and damage control.
Diplomatically, the stipulations of Article III, Paragraph 3 reached last year during session 5 of Nigerian – Cameroun Joint Commission on the Lagdo dam flooding of Nigeria lowlands which require Cameroun to adequately inform Nigeria of future Lagdo dam opening dates are inadequate.
The dams should not be full to a threshed point before its water is reduced. Engineering measures should be put in place to ensure the dam is consistently discharged at a low pressure rate during the rainy season. The dam should never be totally full even though Cameroun will prefer it to be so to boost its hydro-electric power generation. Systemic discharge of water can be better managed and monitored and will not result in excessive flooding as is being experienced at the moment.
It is the responsibility of the governments of Nigeria and Cameroun to ensure that all discharged water is properly channeled and evacuated. Floodways and proper channelization engineered to reduce the velocity of the water should be done by a joint commission of both countries. Building one or more dams by the Nigerian government in strategic locations will effectively curtail this perennial problem.
The dams will serve as a reservoir to store the excess water coming from the Lagdo dam. Good locations for dams, floodways and channelisation or channel modification along the flood plain and along River Benue are Yok and Hausa Dasin which already has an abandoned dam proposal since 1982, all in Adamawa state. Other good areas with vast arable land are Falai which has a mini lake, Damare, Gubari, Kwo, Goron, Numan-Imburu tributary river intersection.
More areas that can be considered are Lav, JiroWudaro, YashinTowo, GarinGada, Mayo Ranewo confluence, KwatanNanidoKambari Reserve, Amar, Mala, Wukari – Amper Rood- River intersection, KatsinaAla, Ajoraku, Egud, Udeni, Aburo, Ocholonya, Iga, Egim. Others are Umaisha, Adausu, Ogba, Mozum, or alternatively at Lokoja. There is also the option of having control dams at Idah, Ogaine or Orimili to control floods to the Delta region.
Other economic benefits of building these dams are enormous. The dams will increase the size of arable lands available for farming. Smaller lakes for irrigation can be created from the dams. It will also allow water transportation to haul farm produce from the rural to the urban centers. Ultimately, the dams can be used to generate hydro-electric power as well as provide clean water for its neighborhood and beyond.
In the same vein, the state governments of the affected areas can augment these efforts by providing retention ponds, levees, dikes and floodwalls to protect critical infrastructure and investments. It is time for the regulatory bodies to start taking pre-emptive regulatory approaches to counter the negative effects of this perennial flood.
Proactively, the urban and land planning authorities in the affected states should immediately commence flood plain or flood prone area mapping. Flood plains should be properly designated and marked out. As a follow-up, the legislative bodies of the affected states should begin to pass laws prohibiting settlement and construction of houses along flood
plains.
For structures that must be situated by floodplains due to economic reasons, the architect, engineers, surveyors, builders and other allied professionals to ensure that these structures are able to withstand the impact of high velocity of water, should proffer proper building codes and regulations. In the same vein, such structures (bridges inclusive) should have formidable clearance from expected high water levels to avoid being submerged in cases of uncontrollable flood.
The amount of money spent on avoidable relief is becoming alarming. It will be better if the government can begin the outright acquisition of all lands within the flood plain areas rather than re-constructing the houses as relief for the inhabitants every year.
WoleAjide is an Architect and resides in Lagos
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