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Causes of seasonal flooding in floodplains: a case of Makurdi, NorthernNigeriaAbah Roland Clement aa Department of Geography, Faculty of Social Science , BenueState University , Makurdi , Benue State , NigeriaPublished online: 10 Oct 2012.

To cite this article: Abah Roland Clement (2012) Causes of seasonal flooding in flood plains: a caseof Makurdi, Northern Nigeria, International Journal of Environmental Studies, 69:6, 904-912, DOI:10.1080/00207233.2012.730668

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Causes of seasonal flooding in flood plains: a caseof Makurdi, Northern Nigeria

ABAH ROLAND CLEMENT*

Department of Geography, Faculty of Social Science, Benue State University,Makurdi, Benue State, Nigeria

This study assessed several factors and their implication for flooding in Makurdi which is locatedin the flood plains of the River Benue. The annual rainfall of Makurdi between 1979 and 2008was analysed for annual totals, intensity, frequency, peak periods and trend to demonstrate propen-sity to cause flooding while records on relief, water table, urbanisation and the river Benue wereexamined for their contribution. This study has identified amongst other things that areas of lowrelief in Makurdi are susceptible to seasonal flooding between June and October annually. Thestudy also identified the causes of floods and factors which intensify floods in Makurdi town.Heavy, intense rainfall and the River Benue spilling its banks are the major causes of floods inMakurdi town. Other factors which intensify flooding in Makurdi town include its low relief, highwater table, urbanisation and human activities.

Keywords: Floods; Seasonal flooding; Flood plains; Makurdi; Nigeria

Introduction

Floods are the most common and widespread of all natural disasters [1]. Many countriesaround the world experience some kind of flooding. Examples include settlements aroundthe Mississippi river in the USA, Bangladesh, Germany, Britain and Indonesia. Flood ismostly an urban problem due to the intensity of land use in urban areas. Flood damage toproperty in urban centres may be very expensive and have additional consequence for insur-ance premiums, raising costs and reducing cover. Loss of human life may be spectacular. Inthe USA, the annual loss of property to flood is estimated to be $12 billion [1], [2].

In Nigeria, several researchers have examined the hydrological changes associated withurbanisation [3–6]. Various factors including topographical conditions, rainfall characteris-tics and land use have been identified as causal factors for floods in Nigerian towns andcities [7]. Studies in Nigeria also include flood hazards studies in Ibadan, Lagos, Ondoand in the Niger Delta [4,8,9]. Others have carried out studies on urban floods and floodrisk assessment [10–13].

In Nigeria, studies on flooding have used case studies from the southern areas of Nigeriawithout particular reference to towns located in flood plains. This study, therefore, attemptsto examine the characteristics responsible for seasonal flooding in Makurdi town which islocated in the flood plains of the River Benue.

*Email: rabah@naca.gov.ng

International Journal of Environmental Studies,Vol. 69, No. 6, December 2012, 904–912

International Journal of Environmental StudiesISSN 0020-7233 print: ISSN 1029-0400 online � 2012 Taylor & Francis

http://www.tandf.co.uk/journalshttp://dx.doi.org/10.1080/00207233.2012.730668

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Study area: Makurdi

Makurdi town is the headquarters of Makurdi Local Government Area (LGA) and capitalof Benue State. The town is located between latitude 7°38′N and 7°50′N, and longitude 8°24′E and 8°38′E. It is situated in the Benue valley in the North Central region of Nigeria.It has a population of about 249,000 and a density of over 380 per km2. It is traversed bythe second largest river in the country, the River Benue.

Makurdi town is located in the plains of the River Benue in the Benue Trough. Therelief is generally low-lying ranging from below 90 to 150 m on the average. There areinterfluves in certain parts of the town where elevation is above the average. The RiverBenue is the main drainage channel traversing the town. It divides the town into the Northand South Banks. There are also several streams draining Makurdi town on either bankwhich are tributaries of the River Benue. Most of the streams are perennial and includeKpege, Adaka, Asase, Idye, Orudu and Demekpe amongst others.

In terms of geology, Makurdi town is composed of sedimentary rocks, with sandstonesas the dominant rock type. Low-lying areas are overlain by shale [14]. The sandstone isdivided into micaceous and feldsphatic sandstones. There are two major soil types inMakurdi town. Hydromorphic soils are developed on alluvium sediments found along theRiver Benue and red ferrasols developed on sedimentary rocks away from the immediateriver channel [15]. Human activities have affected the nature of soils in Makurdi townthrough construction and reclamation.

The climate of Makurdi town is the tropical wet and dry type, Koppen’s Aw classifica-tion, with double maxima. The rainy season lasts from April to October, with 5months ofdry season (November–March).The vegetation of Makurdi town is the Guinea Savannahtype [16].

Many tribes inhabit Makurdi town. These tribes include Tiv, Idoma, Etilo, Jukun, Egede,Hausa, Yoruba and Ibo with the Tivs being dominant. The inhabitants work in the civilservice, commerce and manufacturing industries. Subsistence agriculture is practised exten-sively at the periphery, including some open lands within the town. Market gardening isalso carried out along the banks of the River Benue. Fishing is another importanteconomic activity in the town. Makurdi town has a few medium scale industries such as aplastics business and a fertilizer blending plant. It also has an airport, a soft drink bottlingcompany and a brewery. Commercial activities include the many markets and millingplants.

Materials and method

Primary data collection was done through field observation. Data from secondary sourcesused in this study include annual rainfall data, maps of various themes of Makurdi, recordsof flood occurrence from national dailies and relevant literature. The data on rainfall wascollected for a 30 year period (1979–2008) from the Nigeria Metrological Agency, Makurdibranch. This was the amount of rainfall data readily available for the study. The Ministryof Works provided topographical, drainage, land use and soil maps. The rainfall data wereused to produce relevant tables and graphs explaining the role of rainfall in causing floodsin Makurdi town. The maps of Makurdi town were used to assess the physical attributeswhich contribute to seasonal flooding in Makurdi.

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Results

Causes of flooding in Makurdi

Most flood events in Makurdi are associated with thunderstorms and have occurred afterheavy rainfall within a relatively short period of time; in other words, flash floods. Flashflooding refers to intense rainfall in a relatively short period of time usually with localisedspatial effect. Modification of the overall landscape during a single event is minor in mostvegetated areas but in arid, semi-arid, cultivated or urban areas, such events can be a majorcause of erosion and damage [17]. Short periods of heavy rainfall occur as a result of veryunstable air with a high humidity. Such areas usually occur near warm oceans, near steep,high mountains in the path of moist winds or in areas susceptible to thunderstorms [18].

The causes of floods in Makurdi town discussed in this study start with the major causesand then those which intensify floods. The major causes include heavy rainfall within rela-tively short periods and often associated with thunderstorms and the overspills from theRiver Benue. The factors which are progressively intensifying floods in Makurdi town arelow relief, high water table, urbanisation and human activities.

Annual rainfall

Annual rainfall in Makurdi town is consistently high, with an average annual total ofapproximately 1173mm for the 30 years calculated; rainfall in Makurdi is capable ofinducing floods yearly. Rainfall is highest between the months of April and October eachyear. The highest annual total of 1618mm was recorded in the year 1999 while the lowestannual total of 761.5 was recorded in 2003. Several other years recorded more than1000mm. The implication of these high rainfall totals as related to floods is that they arerecorded in just 7months (April–October) and 80% of the annual rainfall totals arerecorded between June and August each year. Figure 1 shows a graph of annual rainfalltotals in Makurdi from 1979 to 2008. The linear trend calculated for the graph andprojected to 2018 suggests a sustained and slight increase in rainfall activity for the period.This has also been stated elsewhere [19].

Between May and September (1979–2008) monthly rainfall totals below 100mm were notfrequent with August and September (1979–2008) recording between 100 and 460mm.Records for the total monthly rainfall recorded from April to October 1979–2008 were all

Figure 1. Graph showing annual rainfall totals and linear trend in Makurdi from 1979 to 2008.

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above 1000mm (figure 2). These rainfall totals increase the water content in the soil a greatdeal. By July each year, there is much stagnant water in pools visible in various places in thetown. These stagnant water bodies appear as a result of saturated soils due to an already highwater table. Although there is no proper documentation of flood events in Makurdi town,available newspaper records show that most floods occur between the months of July andSeptember annually [20–25]. Isolated flooding cases occasionally occur in May, June, Sep-tember and October. Since most parts of the town are saturated by the end of June, furtheroccurrences of heavy rainfall between the months of July and October raise the water levelsenough to cause damage. Floods of varying intensity occur in Makurdi every year mainlydue to the accumulative effect of singular heavy rainfall and thunderstorm events over sev-eral months (April–October) on already saturated soils.

Highest daily rainfall

Table 1 shows the highest daily rainfall recorded for some of the years under review. Thepattern shows that the highest total rainfall each year was recorded between the months ofJune and October. The highest values occurred more frequently in the months of Augustand September. These extreme values resulted from heavy rainfall and thunderstormswhich fell within 12 h. Towards the end of the wet season in Makurdi town, rainfall maytend to prolong in showers that might last over 12 h but are mostly light or moderate rain.When this happens, flooding is also noticeable in parts of the town with poor drainage andmarshy areas. The highest extreme value recorded in the last 30 years was 149.3mm ofrain recorded in a downpour which did not last more than six hours on the 3rd of August2000. The lowest figure on the table was in 1988 which was 45.2mm in October. Accord-ing to Ologunorisa and Tor [26], 1988 was the driest year on record in Makurdi. Datashown in figure 1 suggest that 2003 may be the driest year so far.

Frequency of heavy rainfall in Makurdi town

In order to establish the frequency of light, moderate and heavy rainfall in Makurdi town,the system of Olaniran [3] was adopted. Light rain in Makurdi town is less than 10.4mm;

Figure 2. Graph showing monthly rainfall totals in Makurdi from 1979 to 2008.

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moderate rain is more than 10.4mm and less than 25.5mm; and heavy rain is from25.5mm and above. Heavy rainfall in Makurdi town is more frequently distributed in themonths of May and September. Heavy rainfall tends to occur most frequently in the monthof August. These occurrences of heavy rainfall contribute to floods in Makurdi because,by the month of August, the water table in most parts of the town is already high due tothe general low relief of the town and the nature of its drainage network which receives asignificant amount of rainfall from the month of April. On average, there are approxi-mately 15 days of heavy rainfall between the months of April and October each year.

The River Benue

The River Benue arises in the Cameroon Mountains. It is drained by many smaller riversand streams (figure 3). Prominent rivers which discharge their waters into the River Benueare the Gongola, Katsina, Ala and Mu. The River Benue reaches its peak capacity in themonths of August and September each year. Towards the end of the wet season, the RiverBenue overflows its banks into certain areas of Makurdi town. The River Benue has beendammed in Ladgo, Cameroon. Flood water from this dam is released at the end of the wetseason each year and contributes to flooding in areas close to the river bank in Makurditown.

The Benue River reaches a mean flow of 3150m3 per s (100 km3per year) for a305,000 km2 watershed. Over the past 20 years, this annual flow has been maintained at97 km3. The average absolute low flow is 240 cum per s and the average annual flood flow

Table 1. Some extreme daily rainfall events in Makurdi.

Days Extreme rainfall amounts (mm)

20 August 1979 71.916 July 1980 76.220 July 1981 123.715 July 1982 71.705 June 1983 7404 August 1984 9515 July 1985 76.830 June 1986 125.322 August 1987 85.327 October 1988 45.218 September 1989 83.306 September 1990 100.727 August 1991 56.611 September 1992 70.510 July 1993 80.322 August 1994 61.713 August 1995 70.629 August 1996 86.307 September 1997 89.513 June 1998 92.925 June 1999 119.303 August 2000 149.302 August 2001 51.311 September 2002 101.107 June 2003 54.730 August 2004 65.8

Source of data: Nigeria Metrological Agency, Makurdi branch.

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reaches 12,000 cum per s [27]. With the concept of global warming and sea level rise inmany literature, cases of flooding in Makurdi town due to the River Benue spilling itsbanks may likely increase in the near future.

The relief of Makurdi town

Makurdi town is located in the plains of the River Benue trough (figure 3). The relief ofMakurdi can be described as generally low-lying with the relief ranging from below 90 to150m which is low enough to induce flooding [14,26,28]. There are interfluves in certainparts of the town where elevation is above average. The nature of the relief is such that watertables in most parts of the town are very close to the surface. Between July and October,water tables rise above ground in many parts of the town. During the period of frequentheavy rainfall between July and September, these pools of water rise to intolerable levelscausing damage to culverts, brick fences and earth roads and in some cases enter residentialhouses.

High water table in Makurdi town

The water table varied from 4.3m (wet season) to 6.4m (dry season) as highlighted byIsikwue [29]. The numerous streams visible in many parts of the town are evidence of ahigh water table. Some of these streams include Idye, Orudu, Adaka, Demekpe, Kpegeand Asase. Apart from the streams, there are many marshy areas, which can be readilyfound in areas close to the River Benue Banks. These marshy areas usually hold pools of

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water visible on the surface of the ground throughout the year. The high water tablecontributes to floods in Makurdi town especially in parts of the town south of the RiverBenue and areas with hydromorphic soils. This is because the northern parts of the towngenerally have a moderately higher relief whereas the southern parts of the town have alower relief.

Urbanisation and human activities in Makurdi town

It is widely accepted that buildings on flood plains increase the risk of flood hazards. AsMoreland [30] rightly puts it,

buildings or other structures placed in flood plains can be damaged by floods. They alsocan change the pattern of water flow and increase flooding and flood damage onadjacent property by blocking the flow of water and increasing the width, depth, orvelocity of flood waters.

Makurdi town is located in the flood plains of the River Benue. The town has witnessed asteady and progressive transformation through urbanisation since Makurdi L.G.A. becamethe capital of Benue State in 1976.

As more people move into Makurdi, more buildings are made to accommodate them.This flattens the land and puts impermeable concrete over the soil along with the removalof vegetation. With less soil to soak up water and less vegetation to absorb water, there isan increase in surface run off which flows into nearby marshy areas and the river Benuewhich increases the risk of a flood. Built up areas in Makurdi which suffer from seasonalflooding include Wadata, Wurukum, Logo, Demekpe, behind Benue State University, Idyeand low-level areas [20–25]. Farming activities in Makurdi such as bush burning andclearing of vegetation for agriculture also contribute to flooding.

According to Tyubee and Anyadike [28], the area of water in Makurdi has decreased by4 km2, representing 19%, from 21 km2 in 1991 to 17 km2 in 2006. The area of forest has alsodeclined by 37 km2 (28%) from 133 km2 in 1991 to 96 km2 in 2006. Similarly, the areas ofundergrowth/wetland and cultivated land have lost 119 km2 (32%) and 19 km2 (14%) from370 km2 and 138 km2 in 1991 to 251 km2 and 119 km2 in 2006, respectively. Conversely,the area of built-up land has increased by 179 km2 (130%) from 138 km2 in 1991 to 317 km2

in 2006. Tyubee and Anyadike attribute decrease in natural land materials and simultaneousincrease in developed land from 1991 to 2006 in Makurdi to urban growth and development.Tyubee and Anyadike regard the major areas of concern as being the degradation of wet-lands and water channels and deforestation due to increase in urban population and unregu-lated land use. Ekwoanya and Ojanuga [31] use (used) aerial photo interpretation andground truthing to assess the flood plain soils in Makurdi. The flood plain soils have moder-ate infiltration rate of 3.2 ± 3.05 cm per h and medium soil texture with sand, silt and claypercentages of 41.5 ± 11.22%, 23.7 ± 11.20% and 35.0 ± 6.79%, respectively.

Recommendations

This study has identified the cause of flooding and factors influencing flooding in Makurdi.Flood mitigating strategies for Makurdi town and other settlements located in flood plainsof major rivers are, therefore, highlighted.

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• A GIS flood hazard database should be created for Makurdi town. Maps of floodrisk areas should be developed as well as data on flood depth, occurrence andamount of damage and extent of damage. This information would guide policy-makers in land use planning.

• Human activities at the banks of the River Benue should be either banned orcontrolled. Earth moving activities at the bank of the River Benue are environmen-tally unacceptable. These activities will only continue to lower the relief at thebanks of the River Benue.

• Marshy areas should not be development land. Marshy areas containing excess run-off from rainfall. The development of such lands will have adverse consequences onsurrounding areas.

• Drainage channels of good depth and width should be constructed in areas known tohave suffered from floods in the past. These drainage channels should be concen-trated in the inland streets where they are absent. Blocked or damaged drainage canlead to accumulation of run-off waters after rainfall. The authorities should conductregular maintenance and ensure unimpeded flow.

• Town planning and land use zonation should be encouraged in Makurdi town. It isimportant not to allow development of urban land block drainage channels or majorrun-off routes.

• Trees should be planted along the banks of the River Benue. Fringe vegetationmakes the soil capable of absorbing floodwaters when a river overflows its bank,and slows down the rate of flow of floodwaters. The planting of trees within thetown should be firmly encouraged. Most parts of the town are becoming uncomfort-able through lack of shade and shelter.

• Levees should be constructed along the banks of the River Benue in areas knownfor frequent overspills.

• The River Benue should be dredged. This will rid it of a considerable sediment loadthereby improving its depth and volume. This will also reduce greatly the risk of anoverspill.

• With a good database, forecasting might help predict periods each year during whichfloods might occur.

Conclusion

The results from this study reveal that seasonal flooding in settlements located in floodplains such as Makurdi is caused by heavy, intense rainfall and the River Benue spillingits banks. Other factors which intensify flooding in Makurdi town include its low relief,high water table, urbanisation and human activities. The findings and recommendations ofthis study would be very helpful in guiding the developmental aspirations of settlements inflood plains.

References

[1] Digby, B., 1996, The Human Environment (Oxford: Heinemann).[2] Raven, P.H., Berg, L.R. and Johnson, G.B., 1998, Environment (New York, NY: Saunders College Publishing).[3] Olaniran, O.J., 1983, Flood generating mechanism at Ilorin Nigeria. Geo Journal, 36, 2–10.[4] Oriola, O., 1994, Strategies for combating urban flooding in developing countries. A case study from Ondo.

The Environmentalist, 14(1), 57–62.

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[5] Ojo, O., 1991, Rainfall distribution and flood hazards in Lagos metropolis area. Proceedings of InternationalSymposium on Meteorological Hazards and Development, Lagos and Kano, Sept. 23rd–3rd October 1989,182–189.

[6] Gobo, A.E., 1991, The 1988 flood in the Niger Delta: The case of Ndoni. Journal of Meteorology, 16(163),36–42.

[7] Ologunorisa, E.T., 2001, An assessment of flood risk in the Niger Delta, Nigeria. Thesis (Ph.D.), Universityof Port Harcourt, Port Harcourt, Nigeria.

[8] Ayoade, J.O. and Akintola, F.O., 1980, Flood perception in two Nigerian cities. Environment International,4, 227–280.

[9] Ologunorisa, E.T. and Adeyemo, A., 2004, Public perception of flood hazard in the Niger Delta, Nigeria.The Environmentalist, 25(1), 39–45.

[10] Odemerho, F.O., 1988, Benin city: a case study of urban flood problems. In: Sada (Ed.) Environmental,Issues and Management in Nigeria Development (Ibadan: Evans), pp. 97–117.

[11] Rashid, H., 1982, Urban flood problem in Benin City, Nigeria: Natural or man-made? Malaysian Journal ofTropical Geography, 6, 17–30.

[12] Omiunu, G.G., 1981, Ogunpa flood disaster: an environmental problem or a cultural fiction. Aman (Journalof Society, Culture and Environment), 4, 110–121.

[13] Ologunorisa, E.T., 2004, An assessment of flood vulnerability zones in the Niger Delta, Nigeria. Interna-tional Journal of Environmental Studies, 61, 31–38.

[14] Kogbe, A.C. (Ed.) 1989, Geology of Nigeria. (Jos: Rock View Ltd).[15] Nyagba, J.L., 1995, Soils and agriculture of Benue State Benue, a land of Great Potentials. In: D.I. Denga

(Ed.) A Compendium (Calabar: Rapid Educational Publishers).[16] Ayoade, J.O., 1983, Introduction to climatology for the tropics (Ibadan: Spectrum Books).[17] Bryant, E.A., 1997, Natural Hazards (Hong Kong: Colocraft).[18] Griffiths, J.F., 1976, Climate and the environment: the atmosphere impact on man (London: Paul Elek).[19] Adesina, F.A. and Odekunle, T.O., 2011, Climate change and adaptation in Nigeria: some background to

Nigeria’s response – Part II. Presented at the International Conference on Environmental and AgricultureEngineering IPCBEE 15, 29–30 July. (Singapore: IACSIT Press).

[20] Ayado, S., 2012, Nigeria: Rainstorm kills 1, destroys over 1,000 houses in Makurdi, Leadership Newspaper,15 July.

[21] Wantu, J., 2012, Rainstorm wreaks havoc in Makurdi, Guardian, 21 May.[22] Wantu, J., 2011, Flood wreaks havoc in Makurdi, Nigerian Voice, 8 October.[23] Nwakaudu, S., 2009, Flood sacks Makurdi residents, destroys properties, Online Nigeria, 16 October.[24] Hir, J., 2009, Benue farmers get N23 million compensation for floods, Africa News Service, 9 July.[25] Hir, J., 2008, Construction coy causes flood in Makurdi, Africa News Service, 4 August.[26] Ologunorisa, T.E. and Tor, T., 2006, The changing rainfall pattern and its implication for flood frequency in

Makurdi, northern Nigeria. Journal of Applied Science and Environmental Management, 10(3), 97–102.[27] Andersen, I., Dione, O., Jarosewich-Holder, M. and Olivry, J., 2005, The Niger river basin: a vision for sus-

tainable management (Washington, DC: The International Bank for Reconstruction and Development /TheWorld Bank).

[28] Tyubee, B.T. and Anyadike, R.N.C., 2012, Analysis of surface urban heat island in Makurdi, Nigeria.African Climate Change Fellowship Program (ACCFP). Available online at: www.goes-r.gov.

[29] Isikwue, M.O., Iorver, D. and Onoja, S.B., 2011, Effect of depth on microbial pollution of shallow wells inMakurdi metropolis, Benue State, Nigeria. British Journal of Environment & Climate Change, 1(3), 66–73.

[30] Moreland, J.A., 1993, Floods and flood plains. United States Geological Survey Report 1993 (USGS OFR93-641). Available online at: http://pubs.usgs.gov.

[31] Ekwoanya, M.A. and Ojanuga, A.G., 2002, Productivity assessment of upland and floodplain soils atMakurdi, Nigeria. Geoderma, 108(1–2), 19–29.

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