INTRODUCTION
In the past century, large dams became a prominent instrument for economic development. Worldwide, the number of large dams stood at 5000 in 1950; three quarters of these were in North America, Europe, and other industrialised countries. By 2000, the number of large dams had climbed to over 45,000 and these were spread among more than 140 countries. On average, two large dams were built per day for half a century. Currently, the number of large dams exceeds 50,000. These dams provide water storage that has enabled large cities like Phoenix, Arizona in the United States, to grow in desert regions. They supply hydropower that has electrified many rapidly expanding industrial and urban economies, from Seattle to Shanghai. Also, large dams are important in agriculture. About half of the world’s large dams were built primarily for irrigation, many of them in Asia as the Green Revolution spread. Today, large dams are estimated to contribute directly to 12-16% of global food production. Definitely, large dams have played an important role in economic development.
However, large dams have also brought serious environmental and social consequences. Whereas the benefits have generally been delivered to urban centres or industrial-scale agricultural developments, riparian river-dependent populations located downstream of dams have commonly experienced a difficult disturbance of their livelihoods, loss of food security and other impacts to their physical, cultural and spiritual well-being. River flows altered by large dams often disrupt or destroy downstream habitats and life cycle cues for fish and other river species, as well as fishing, cropping and grazing systems that rely on flood-plain socio-ecosystems. While riparian river-dependent communities may benefit from some degree of flood protection and enhanced irrigation opportunities provided by dams, adverse impacts are far more common and usually outweigh the benefits to downstream people, resulting in reduction of their incomes and livelihoods.
Although, the nature, duration and severity of these impacts vary from one dammed river to another, in some of the cases documented, the wave of social, physical, cultural, spiritual disruption and human health impacts following dam construction largely passed within a decade. In other cases, dam-induced impacts have persisted through multiple generations. In some cases, impacts may be mitigated by alternative sources of food or employment; in other cases, they may not. And in some cases, the environmental effects of dams are detectable for only a short distance downstream, while in others those effects remain significant through hundreds of river kilometres. Nevertheless, what the majority of cases have in common is the failure to account for these impacts and their consequences on downstream populations.
These cases prompted me to overtly write on: the perpetual occurrence of flood in the Hadejia Valley; the human and material costs of the damages; little or absence of relief, control, mitigation and management of this man-made disaster and finally nobody seems to know why it periodically happens and the failure to account for these impacts and their consequences on downstream communities. Therefore, I would like to open a forum through this write-up on the downstream human and material consequences of flood in Hadejia, its environment and beyond with a cautionary quote from a report. Thus;
“Any scheme of flood releases from present and projected reservoirs can only be undertaken with a much improved monitoring network of instruments, greatly enhanced levels of training amongst responsible staff, and a very close and effective liaison between the river managers and those who actually use the rivers and their waters. It is essential that the timing of the releases is correct. Too much water, too early in the season and the planted seed will be drowned. Too little water, too late and the small rice plants will wither and die before the onset of the flood. A big reservoir release, when flood conditions already exist from heavy rainfall and large discharges in tributaries, could cause serious damage to bridges and the inundation of towns and villages. Similarly, it will be essential that the releases in the Hadejia River are carefully coordinated with those in the Jama’are River so as to derive maximum benefit in the wetlands and downstream of Gashua. Such coordination will require substantial studies of the hydrology of the rivers using daily data, greatly enhanced understanding of the mechanisms of flooding and groundwater recharge, and probably the development of a real time forecasting and control model for the river basin. So, whilst such a scheme of flood releases may be shown to be technically feasible and economically desirable, it is essential that perhaps a decade of planning and organization be undertaken before any such scheme is implemented.” IUCN Report (1993).
In Nigeria, flood disaster has been perilous to communities and institutions. It has shattered both the built-environment and undeveloped plan. It has claimed many lives, and millions of properties got lost due to its occurrences. One prominent feature about it is that flooding does not discriminate but, marginalizes whosoever refuses to prepare for its occurrence. Flood affects more people on an annual basis than any other form of natural disaster, a variety of climatic and non-climatic processes influence flood processes, resulting in different types of floods. This shows that flooding in Nigeria could be as a result of natural or human cause, categorized as follows: Natural causes;
a. Heavy rainfall,
b. Oceans storms and tidal waves usually along the coast,
c. Lack of Lakes, and
d. Silting Human causes.
While other human causes of flooding in Nigeria may be due to one of the following factors;
a. Burst water from main pipes,
b. Dam failures,
c. Population pressure (especially in the city of Lagos),
d. Deforestation (such as North part of Nigeria),
e. Trespassing on water storm drains (key cause in Southern Nigeria),
f. Unplanned urbanization (in many cities it’s the key cause of urban flooding),
g. Poor Sewerage Management,
h. Neglecting warnings from hydrological system data (major cause of 2012 flooding in Nigeria), and
i. Lack of flood control measures (especially by government).
Unfortunately, in Northern Nigeria, the construction of dams and other water projects upstream have already affected irreversibly the hydrology of the Hadejia-Jama'are floodplain such as the recent flood release which brings us to delve into the conception of irrigation in the valley area.
THE CONCEPT OF IRRGATION
In Nigeria, the records indicate that the conception of large irrigation projects in the Hadejia area came as a result of a study conducted in the mid-1960s by the United States Bureau of Reclamation which was financed by the United States Agency for International Development (USAID). One of the analyses included the possibility of construction of several dams on rivers that drain the upper reaches of the Chad Basin through the Hadejia and the Yobe Rivers into Lake Chad. Moreover, the structural property of the Hadejia Valley Irrigation Authority (HVIA) which lies in the North-Eastern Kano State (now in Jigawa State) is a natural advantage for large irrigation project. The valley is about 5 miles wide and 20 miles long and lies between the Hadejia and Kafin Hausa River loop.
However, the Hadejia River is the valley‘s northern boundary while the Kafin Hausa River borders the southern part. The valley area covered slightly more than 28,340ha (70,000 acres). Land formations within the project area, such as land dunes, lake bodies, and swampy areas as well as villages reduced the farming area to approximately 24,300ha (60,000 acres). During the Third National Development Plan (1975-80), the need for rapid production of food and industrial raw materials became obvious in the face of rapidly growing population and the experiences of devastating droughts. It was in this context that ―River Basins" concept came to be adopted.
Accordingly, the Hadejia Valley Irrigation Authority (HVIA) was taken over by the Hadejia- Jama‘are River Basin Development Authority (HJRBDA) from the Ministry of Agriculture and Natural Resources (MANR), Kano State in 1976. The location of Hadejia Valley Irrigation Authority continued to be maintained as done by the MANR but, the original plan of small schemes in the projects at Agubu, Arawa, Ganuwar Kuka, Mai Alkama, Sunamu, Tashena and Yamidi operated by the ministry was renamed Hadejia Valley Irrigation Project (HVIP) and consolidated into two Phases (I and II). Operationally, Hadejia-Jama‘are River Basin Development Authority (HJRBDA) covers areas in Kano, Jigawa, and Bauchi States with a potential irrigable space of 250,000 hectares. The objectives of the authority among others include: harnessing, conservation, and efficient utilization of available water resources within its area of jurisdiction for increased agricultural production and domestic water supply (italics mine). The question is: How does the authority harnesses, conserves and efficiently utilizes the available water resources looking at the recent records on flood occurrences in the basin and beyond? This leads us to the upstream-downstream nexus.
UPSTREAM-DOWNSTREAM NEXUS IN THE VALLEY AREA
The Hadejia basin is located in the North Western part of Nigeria on the Hadejia River. It falls within geographical coordinates of 12º26’N and 10º04’E and has a drainage area of 25,900km2. The upstream section of the Hadejia River system lies on the largely impermeable Basement Complex rocks. The upstream Basement Complex region is hilly (with peaks of up to 1,200 m). Most of the flows in the Hadejia River system (∼80%) is regulated by Tiga Dam. The Hadejia River splits into three channels in the Hadejia Nguru Wetland: The Marma channel which flows into the Nguru Lake, the old Hadejia River which joins up with the Jama’are River to become the Yobe River and the relatively small Burum Gana River.
Nevertheless, the largest upstream irrigation scheme at present is the Kano River Irrigation Project (KRIP). Water supplies for the project are provided by Tiga Dam, the biggest dam in the basin which was completed in 1974. Water is also, released from this dam to supply Kano City. The second major irrigation scheme within the river basin, the Hadejia Valley Project (HVP), is under construction. The HVP is supplied by Challawa Gorge Dam on the Challawa River, upstream of Kano, which was finished in 1992. Besides, Challawa Gorge provides water for Kano City water supply. A number of small dams and associated irrigation schemes have similarly, been constructed or are planned for minor tributaries of the Hadejia River.
In comparison, the Jama’are River is relatively uncontrolled with only one small dam across one of its tributaries. Plans for a major dam on the Jama’are at Kafin Zaki have been in existence for many years, which would provide water for an irrigated area totaling 84 000 ha. Work on Kafin Zaki Dam has been started and then stopped a number of times, most recently in 1994, and its future is at present still unclear. Therefore, Tiga and Challawa Gorge dams control 80% of the flows into the basin and are operated by the Hadejia-Jama’are River Basin Development Authority (HJRBDA) as stated earlier which is the nexus between up-and downstream of the river, and planning for the lower part of the basin is conducted by the Chad Basin Development Authority (CBDA). This shows that there are two major authorities as the dichotomy suggests.
However, a myriad of questions are: Is there a hydrologic boundary between the two- HJRBDA and CBDA? Is there a coherent, integrated development plan for the entire basin? Is there much coordination between the agencies responsible for the dams and those for water supply in the basin? Furthermore, is there a communication channel among the six states (Jos, Kano, Jigawa, Bauchi, Yobe and Borno) in the basin, the Diffa province in Niger within the basin and the federal planning and management authorities? How many agencies of government at various levels share some degree of jurisdiction over water management in the basin? Do dam operators in the basin have inflow monitoring devices, inflow forecasting tools for the reservoirs? Is there a flood warning system for the basin? What happens to the proposed river basins’ flood early warning system of 2009? (italics mine)
Nonetheless, based on the irreparable damages that have resulted from flooding in the basin, there is a dire need to direct urgent attention towards these and many more questions. Now let us look into the mechanism of flood management and control in Nigeria.
Management and Control of Flood in Nigeria
The Government of Nigeria is the primary initiator of measures for the management of flooding in Nigeria. Various institutions, policies and regulations have been set up by government to address issues relating to floods and activities that promote/influence flooding in Nigeria. These agencies are:
National Environmental Standards and Regulations Enforcement Agency (NESREA)
This is an agency of the Federal Ministry of Environment that is saddled with the responsibility of enacting and enforcing regulations that protect the environment from degradation. Examples of some flood-related regulations are:
i) Watershed, Mountainous, Hilly and Catchment Areas Regulations 2009: Aims to check and restrain activities in the above-mentioned areas that are inconsistent with proper land practices.
ii) Wetlands, River Banks and Lake Shores Regulations, 2009: The objectives of these regulations are management and conservation of water catchments and flood control, conservation and sustainable use of wetlands and pollution control.
National Emergency Management Agency (NEMA)
The Nigerian government established the National Emergency Management Agency (NEMA) through (Act 12 as amended by Act 50 of 1999), to manage and respond to disaster related activities in Nigeria such as flooding, accidents caused by natural and man-made sources. NEMA is saddled with the responsibility of formulating policies, assessment of natural and man-made disasters, provision of mitigating measures for disaster related activities, coordinating plans and programmes for offering relief items to victims of such disasters. It is essential to assess the activities of NEMA as it relates to identification of flood risk areas in order to develop prevention/mitigation measures in controlling flooding in the area.
National Erosion and Flood Control Policy (NEFCP)
This agency was established in 2005 with the goal of protecting the environment from degradation, loss of productive land and negative impacts of flood. They are responsible for ensuring coordinated and systematic measures in the management and control of the hazards of erosion and floods to reduce their impacts on people and the environment.
Since the inception of these agencies, policies and regulations, the country’s response to flood risk management has still been mainly that of relief management after a flooding incident. Even then, co-ordination of rescue operations has always been slow, exacerbating the damage and loss in the aftermath of the event. Part of this problem may be due to lack of technical expertise for handling environmental issues and insufficient information on flood vulnerability of different parts of the country, hence the need to introduce proven strategies to combat this menace. For instance, taking stock of flood occurrences in the basin 35, 500 people were displaced in 1988, also, it occurred in 1991, 92 and 93, 450,150 people were displaced in 2001 (Etuonovbe, 2011), 1.5 million farmers, herders and fishers were displaced (Nigerian Conservation Foundation, 2006), floods occurred in September, 2012, 15, 17, 18, and 19 (Legit Natural disasters in Nigeria: Top 5 of all times) and September, 2020.
THE WAY FORWARD
It can readily be acknowledged that dam development projects have played a very important role in advancing local and national economies thus, the fact that dam development projects can provide important local to national benefits, including benefits that flow to downstream communities is not at issue here.
Therefore, what is at issue is the degree to which dam projects degrade the natural food productivity of river socio-ecosystems and disrupt livelihoods and cultures dependent on these systems without an accurate accounting of these costs.
Moreover, as described below, many of these negative consequences can be avoided by applying pragmatic 'best practice' approaches to overcome the recurrent problems of floods along the Hadejia Valley. The Hadejia-Jama’are River Basin Development Authority (HJRBDA) and the Chad Basin Development Authority (CBDA) should apply the followings:
The need to identify, classify and map those areas subject to flooding as the basis for flood preparedness and management,
The potential offered by remotely sensed radar photos to monitor and identify rapidly inundated areas, overcoming problems of overcast skies during flood periods,
The use of GIS techniques to make inventories and analysis in a more systematic manner the impact of floods on agriculture and infrastructure,
The urgent need to update the basin’s capabilities in flood forecasting and river modeling,
The need to incorporate flood management as an integrated element in reservoir operation,
The considerable potential of flood control works to offer more lasting solutions in flood management,
The need to create a greater local awareness and preparedness in flood relief, mitigation and management,
The potential for promoting dry season irrigation to offset yield reductions due to flooding,
Redesign of physical structures that cut across the basin such as roads with high bridges instead of culverts, dredging of old water outlets north of the basin that could serve as spillways and be utilised in the dry season,
The need for a proper institutional capacity at central and decentralized level to address flood problems on a continuous basis. For instance, coherent, integrated development plans for the entire basin, much coordination between the agencies responsible for the dams and those for water supply. Additionally, communication among the six states (Jos, Kano, Jigawa, Bauchi, Yobe and Borno), local government areas in the basin, the Diffa province in Niger within the basin and the federal planning and management authorities, and
The need to collaborate with stakeholders which include: vulnerable communities resident in the hydrological, Community Based Organizations, Local, State and Federal Governments of Nigeria, Government Agencies and Institutions, the Private Sector, the Academic and Scientific Community, Non-Governmental Organizations, Regional Institutions and Organizations, and International Organizations.
Otherwise, Hadejia Valley will be lost in development’s shadow as a result of the downstream human consequences of dams by taming the river. Thank you and remain blessed for reading and anticipate your response.
Mohammed Bashir Umar
